Researchers have detected signals that may indicate the existence of a giant Neptune-sized moon orbiting a Jupiter-sized extrasolar planet 4,000 light-years away. The researchers emphasize that the identification is not certain, and they will soon make follow-up observations with the Hubble Space Telescope to confirm its existence.
In recent years we have witnessed increasing discoveries of planets outside our solar system, most of them thanks to one of NASA's most fruitful space missions - the Kepler Space Telescope. Now, the telescope may help make the first discovery of a moon outside the solar system Exomoon, "Exo-Mon"). A team of researchers recently revealed that they were able to detect signals in the data measured by Kepler, indicating the possible existence of an extrasolar moon.
The possible identification was made within the framework of the HEK (Hunt for Exomoons with Kepler) project, which is the first scientific collaboration dedicated to the search for extrasolar moons.
The researchers emphasized that the identification is not certain yet, but if it is verified, in follow-up observations planned for this year by the Hubble Space Telescope, it will be the first ever discovery of such a body. Dr. David Kipping from Columbia University in New York, who heads the team of researchers, tried to sound skeptical andtold the New Scientist website: "We had candidates in the past that we investigated, and most of them faded away." "At this point we only describe it as something that coincides with the moon, but who knows, maybe it's something else," he Told the BBC.
The extrasolar planet around which the supposed lunar holiday is Kepler-1625b, and if it does exist - the researchers Place whose distance from the planet is about 2 million km. The planet itself is in a roughly 290-day orbit around a star almost twice the size of our sun. The entire system is about 4,000 light years away, in the constellation Cygnus.
The proposed moon is completely different from what we know in our solar system - it is similar in size to Neptune (which is 4 times larger than Earth), and orbits a planet the size of Jupiter (but with a mass 10 times greater than that of Jupiter). In our solar system, the vast majority of the moons are very small compared to the planet they orbit, with very few exceptions (including the Earth's moon and Pluto's coffin moon).
Since the moon is very large in relation to its planet, the researchers rule out the possibility that it was formed together with the planet from the crystallization of particles in an ancient disk of gas and dust, from which a planetary system is formed, as the accepted theory explains the formation of the moons of gas giants like Jupiter in our solar system.
Instead, the researchers propose two possibilities for the formation of such a huge moon - one possibility is that it formed separately and was later captured by the planet's gravity, similar to the moon triton of Neptune. The second possibility is reminiscent of the supposed formation of the Earth's moon - a massive collision with the planet may have thrown a lot of material into orbit around the planet, which later crystallized into a moon.
The researchers discovered the signs indicating the existence of the moon in a similar way that its planet was discovered. Due to the enormous distance, current technology does not allow direct observation of the planet, and certainly not of its moon. Instead, the researchers use several indirect detection methods. One of them, the "eclipse method", looked for the dimming that the planet creates in the light of the star, when it passes between it and the telescope.
When the planet has a moon, it too may create a small dimming of the starlight - before or after the main dimming of the planet, depending on its position around the planet at the time of the eclipse. In the data measured by Kepler, three eclipses of Kepler-1625b were recorded, in which you can see the decline in the intensity of the star's light, which is created by the planet itself. In addition, a smaller fade can be seen, which precedes or follows the main fade. In the third eclipse in the diagram (see image below) you can see that the secondary dimming appears both before and after the main dimming.
Until now, previous detections of extrasolar moons, which were announced in waves in the media, were later disproved. In this case, however, the researchers noted that so far it has survived all the tests that disproved previous discoveries. According to them, the level of confidence in the identification is 4 sigma, which means that there is a 1 in 16,000 chance that the information measured is a coincidence. However, they emphasize that it is still difficult to determine with certainty that the responsible factor is necessarily the moon.
To verify their hypothesis, they will soon make a follow-up observation using the Hubble Space Telescope, which has higher capabilities than Kepler. The observation will be made on October 29 this year, when Kepler-1625b will make another eclipse around its star, and the researchers hope to observe again the secondary eclipse that its moon will make, if it does exist.
It is worth noting that the researchers did not want to publish the possible identification now, and preferred to wait until it was confirmed through Hubble. Alex Tichy, who is participating in the study, explained In the blog on the Scientific American website: "The announcement and later return of results that may be groundbreaking, causes an erosion of public trust in science over time." However, since that their request To make an observation on Hubble was exposed to the public and was going to be published by now, the researchers preferred to publish it themselves in a slightly more responsible way. There was also a less altruistic reason for their decision - they feared that another scientist would use the information to register the discovery in his name. Now we have to wait and wait a little to check if this discovery will not "disappear" in the future.
See more on the subject on the science website:
- Looking for moons around planets outside the solar system
- The Kepler space telescope found 219 more planets and revealed a clear gap between terrestrial planets and mini-Neptunes
- A system of seven Earth-like planets was discovered, three of them in the zone suitable for the existence of liquid water
126 תגובות
By the way, it's not the "photons that created the shape of the planet" (as you wrote). This is one photon that is 'spread' over the entire area...
The separation capacity (resolution), of the lens, is what is responsible for a more detailed image - thanks to photons that are absorbed and separated from each other... dumbass.
Obviously, I didn't understand you, rival. I really have a hard time understanding things that are nonsense. That's why I pointed out where you and the "wise men" who answer you are wrong, and what you are missing. So, after eating your pride and adopting the right things I wrote (and of course, appropriating them to yourself), you still allow yourself to run your mouth...
Obviously I was talking (and I explained this) only about the photons that hit the lens and caused the star to appear in the image, obviously they were not isolated from the other photons and light rays that came from that star and hit the telescope lens at an inappropriate angle or the area around the telescope and therefore did not appear in the image. Everyone understood, except for one jerk.
anonymous,
I really didn't expect a moron like you to understand, luckily there are some smarter people here.
Really cool 🙂 The idea about discovering the planet through gravity came to my mind immediately when you talked about how the planet has enough gravity to bend the light rays "and close" the dark area created there. Soon I will go (for the first time) to the link you gave, it sounds really interesting 🙂
rival
We have dealt with your suggestion 🙂 The Wikipedia link contains a description of the gravity method. Until I read it, I didn't know.
Although I was mainly talking about the effect on light intensity, the principle is similar, using the stars and galaxies that are in the background to detect planets that are in range.
It's strange that throughout this long thread no one has mentioned the method of detecting planets using gravity.
Miracles,
I haven't had time to go to the link yet, but what are you actually saying? That the method I proposed for searching for planets through their influence on distant stars that are behind them in the background, really works?
rival
In the link I gave, they explain exactly that - using gravitational pull to look for planets. And what you find is that every star has at least one or two planets.
Miracles,
An Earth-sized planet in the path of the light rays from a distant star towards your telescope is still a serious obstacle in the way, and I think that this obstacle will be measurable anyway.
1. From what I understand, you claim that the light rays that bend a little when they pass close to the planet, will "cover" at a large distance the shadow or the dark area formed on the other side at close distances. There is some logic in this, but I still don't think that the uniformity of the flux of light rays will remain uniform after the encounter with the planet. At any distance where you measure the light intensity of the star from the other side of the planet, there will be a measurement unevenness in the light intensity as a result of the encounter with the same barrier, the light intensity will not be the same everywhere.
2. If your calculations are correct and the planet really creates at great distances such a large deflection of the light rays you should clearly recognize it in your frame, the star should move noticeably as soon as the planet passes between it and the Earth. If you took 50 frames and the star was in a certain position, as soon as the planet gets closer, you will reach the "hiding" point and then move away. You should clearly see in the following frames that the star moves from its place and moves to another place, and then returns to its original place.
So in any case you will be able to detect the transition, whether through a change in the intensity of the light, or through the displacement of the star (as in Einstein's famous experiment with the solar eclipse and the star).
rival
Yes, close to the planet will show a dark area on the surface of the star. When you move away, this area will of course decrease.
But - there is always a light that "sneaks up from behind". In classical physics, this light comes from two sources: diffraction and the curvature of space.
I have no idea how to calculate the effect of the curvature, but the formula for calculating the effect of the curvature of space is simple:
https://en.wikipedia.org/wiki/Gravitational_lens#Explanation_in_terms_of_space.E2.80.93time_curvature
Miracles,
What about light rays that directly hit the soil of the planet which is 10,000 km in diameter, aren't they supposed to leave some kind of dark and black "hole" on the other side of the planet?
am i a fish Maybe the Chinese sage and vegetarian Yang grilled fish?
Indeed, if the moon hides the sun, you will be able to see the reflections of the sun in the environment - but you will not be able to see the sunspots, the face of the moon or the storm rightly (or wrongly).
For this you will need a clean space without interruptions.
rival
Your question is good. I think the point is that both bodies are… points 🙂
Because of the tiny angular size, any angular change in the light's path will cause some of the light to pass in front of the star.
I found on the net that the earth causes a deflection of 0.16 millionths of a degree. Let's look at the angular size of the Earth from a distance of 10 light years. I use a pilot trick called the "one in sixty" rule.
The diameter of the earth is about 10,000 km
10 light years is 100 trillion km.
We will divide and get a tenth of a billionth.
Therefore - if we multiply by 60 we get 6 billionths of the degree, that is 0.006 millionths.
That is - the deviation of gravity is 200 times!!
"Therefore, because we ***do receive*** a focused image of the star on top of the frame, it follows that there must be a relatively narrow and concentrated beam of photons that made its way from that star to the lens of our telescope."
This sentence will only be true if there is an alien, who is on the same planet, and sends a laser beam (in the shape of his planet?!) that hits the telescope lens...
And it still seems "trivial" to him...
Miracles,
1. "I showed you a pair of scissors and you're wrong." The curvature of space is orders of magnitude greater than the obscuration of the planet. What's wrong with that?'
The part that I didn't understand anything from what you said there, I was hoping that maybe Israel Shapira would say something on the subject but for some reason he is as silent as a fish.
2. How about addressing specifically the claim I made? If the photons that create the image of the star in the frame are not concentrated as one narrow beam of photons moving in parallel lines, how do they manage to create such a focused and beautiful image of the star in the frame?
And if you agree with me that indeed a narrow and concentrated beam of photons creates the image of the star in the frame, then why do you think that a huge, opaque barrier the size of the Earth (huge compared to the narrow beam of photons trying to reach the telescope) will not be able to stop it from reaching your telescope?
It seems trivial to me.
rival
I showed you a pair of scissors and you are wrong. The curvature of space is orders of magnitude greater than the obscuration of the planet.
What's not good about it?
For anyone who still wants to continue the discussion, my argument is simple -
To create a tiny point of light on the frame, one that represents a sun that is thousands of light years away from us, there must be a narrow and concentrated beam of photons that came out of that distant sun, traveled all the way to us, and hit the telescope lens at a very specific angle, an angle that determined the position of The same star in our frame.
If the same photons that represent the star in the frame were scattered on their way to us in all sorts of random directions due to space dust, galaxies and asteroids, they would not form a star focused in the frame but just a huge, blurry spot that we would hardly recognize as a star at all.
Therefore, because we ***do get*** a focused image of the star on top of the frame, it follows that there must be a relatively narrow and concentrated beam of photons that made its way from that star to the lens of our telescope. Therefore it is also clear that a planet the size of the Earth will block the path of such a narrow beam of photons, and will not allow it to reach the lens of our telescope.
That's why we seem to be hiding.
rival,
I didn't ask you to read minds. I asked you to read a text. If you only look at two or three sentences I wrote and ignore all 5-10 paragraphs that accompanied them, then it's not surprising that you couldn't understand. What about the thing I wrote that the experiment must be performed with a light source that is not point or focused, and that it must be large? Does your and Israel's experiment reflect this? Israel said he used his iPhone flashlight, which I know well and it does not meet any of these definitions. If you had also looked at the (many) explanations of the physics behind the experiment I wrote, you wouldn't have had to blindly quote two sentences from all my comments. I also explicitly wrote that the sphere will hide the light that hits it, but what I explained is that the amount of light is proportional to its angular size, which is small when it is far away.
And some final comments (this time really final): 1. There is a lot of reflection in the light that reaches us. Between us and the stars we observe there is an intermediary (such as dust, galaxies, asteroids, etc.). The medium plays an important role in observation.
2. You have already been told that light rays do not move in a straight line.
3. Most important: if you look at the center of a galaxy, you see a spot of light. This patch of light typically contains many billions of stars. So why do we only see a speck? Why not see all the points? Because because of the great distance, all this huge object, comes more or less from the same direction and hits more or less the same place in the detector. Likewise, all the light emitted by the star (which is typically thousands of times larger than planets that can hide it) is averaged over a very small area in the detector. Therefore, even without reflection you will get a lot of direct light, and the question is how much of it will be lost on the way because of the planet. As I explained earlier - it's a question of how much the intensity will decrease.
Think I'm wrong? Ok. I would expect that in this case you could point out my mistake, either on a mathematical level (as I said, calculating the change in flux is really easy) or on a physical level. But if you rely on intuition, I have nothing to say. No one will force you to agree with me - certainly not me. I wish you that here or there, right or wrong, hiding or not, the matter will become clear to you soon.
Israel, don't complicate matters for me now with quantum theory, okay? The photon came out of the sun and moved at the speed of light towards the telescope lens, that's it.
A final correction I hope - I think it is more correct to ask what the ***average*** diameter of that roll of fiber will be, since most likely it will be its diameter if and when it encounters a planet standing in its way.
"The exact trajectory of each and every photon"
Is there such a thing?
Oops easy correction, I meant to say - paint in red only the path of the photons that created a single point of light (star) in the final image.
Let me ask this, if you could color in red the exact path of each and every photon that hit the lens of the Hubble Space Telescope at a certain moment, from its point of departure until it hit the lens, I imagine you would get a kind of long cylinder made up of lots and lots of fibers (each fiber represents the trajectory of one single photon) that leaves a certain point in space where the star was, and reaches the telescope lens.
In the thickest place (which contains say at least 80% of the photons in that section) would the diameter of that cylinder of photons exceed 10 kilometers? If not, what would happen if that long roll of photons that was on its way to our telescope, encountered a barrier the size of the Earth? What percentage of the photons in that narrow cylinder will manage to bypass the obstacle and still reach our telescope lens?
elbentzo,
I'm sorry but I haven't learned to read minds yet, when you repeat and emphasize message after message:
1. "See that the ball suit ***will do nothing to the light you see from the flashlight***..."
2. "A tennis ball that will pass exactly on the line connecting you and the flashlight ***will not hide the flashlight..."
3. "Passing a tennis ball near the headlight will hide the light, and also passing a tennis ball near your face will hide the light, ***but in the middle it won't***"
So the only thing that can be understood from such a wording is that ***at least*** 95% of the amount of light that previously reached my eyes (or the measuring means) without obstruction, will continue to reach my eyes even when the obstruction is placed in the middle of the road.
But practically the opposite happened, both in my experiment and in Israel's, 99% of the amount of light was blocked! The flashlight was hidden!
See what Israel wrote:
"****I didn't see the light of the flashlight****, but the reflections - from the garden, from the trees, from the air - can be clearly seen"
How are the rays of light that hit the barrier and were reflected in the trees in the garden and in the air relevant to our case? Are there trees, benches and other objects near the planet that the light splashed from the planet backwards and to the sides can be reflected in?
I really appreciate your knowledge and your attempts to explain things, but my intuition and also the results of the experiment tell me that on this subject you are not right. It is true that the distant sun emits light in all directions, I agree with you, but out of all this enormous light scattered from it in all directions, here on Earth we can only receive and see a narrow light beam of photons that came from the sun to the lens of our telescope whose maximum diameter is 2.5 meters! That is, if somewhere in the path of that narrow light beam there is a large barrier, such as a planet the size of the Earth, then this light beam that was on its way to our small telescope will get stuck in the soil of the planet and will not continue towards the telescope.
The light of that beam will hit the ground of the planet and part of it will be reflected up and to the sides, but not in our direction, so at this moment (let's assume for a moment that the speed of light is infinite) it seems that the point of light we saw before suddenly disappeared.
rival,
The experiment as Israel describes it is exactly what I said would happen. I don't understand, do you think I'm claiming that the tennis ball has miraculously become transparent? I explained again and again - the light scatters. Therefore, the light that gets stuck directly in the tennis ball will not reach you, but there is a lot of light that "bypasses" the tennis ball and also reaches us. In the case of Israel, it was clear to him that this light hit some tree in the dark garden and returned to his eyes from this tree. But when the telescope collects light, it does not know what the trajectory of each photon that reached it was, it does not have the resolution to understand whether there was a reflection from another object or not, and also - as you were told earlier - the paths of the rays are not straight and therefore some of the light can reach the telescope even without No reflection. All we can see is the change in the amount of light that reaches the telescope - and this change will be zero when it comes to an "obscurer" that is not very close to the hidden light source. That's why I also asked you if you claim that there is no difference between a completely dark room, and a room with an LED light that is hidden by cardboard 10 meters away from it (I don't know exactly the size of your apartment, let's say 10 meters between the cardboard and the light). Because according to what you claim - all the light from the LED is blocked, so a person entering your apartment should not be able to differentiate between the two cases. But it is clear to anyone who has ever seen a lamp that it will be possible to tell the difference, because some of the light will bypass the cardboard. It might be clear to us because we have sharp eyes and high resolution, but in a telescope whose every pixel has summed up astronomical amounts of photons that didn't necessarily come at the same time from the exact same point, you'll just get a smudge of light. The difference between the light spot without a planet obscuring and with a planet obscuring directly depends on the distance between the planet and the star.
And again - as I already explained - the only exception here is the case when the obscuring object is very far from the hidden light source, but very close to the telescope. This is a trivial statement - like saying that even a thimble can hide all the sunlight (if I attach it to the retina of your eye).
Miracles,
"Furthermore, think about the next point. Look at the north pole of the star. He himself is a point of light that scatters rays in all directions. The light from this point is enough to hide the entire planet.'
I think that what is relevant for us for the purpose of this discussion are the rays that are emitted from the star towards the earth (assuming there are no disturbances and diversions on the way) I imagine a kind of cone of rays that come out from a certain area of the star (in the same distant sun) towards the earth, and the ones that will eventually hit the earth are these which we see in our telescopes.
If on the way, these rays suddenly encounter a planet, I see no reason why it would not block their path, and then we will see a significant reduction in the luminosity of that star, maybe we will only see a few weak rays that managed to bypass the planet's mantle, but the rays that hit the center of mass of that planet They will stop and not continue in our direction.
Miracles,
What you say is completely clear to me (that the sun's rays come out of its entire circumference and that they have "volume"), but it still doesn't work out for me, and I didn't understand Albentazo's explanation, and neither my experiment nor Israel Shapira's experiment were able to show what Albentazo claims should happen .
My intuition and understanding tell me that just as our moon manages to hide the giant sun during a solar eclipse (or at least reduce its light intensity by 99%) so a distant planet will manage to hide the beauty of a star that is tens or hundreds of light years behind it.
rival
Beyond that, think about the next point. Look at the north pole of the star. He himself is a point of light that scatters rays in all directions. The light from this point is enough to hide the entire planet.
To see this phenomenon, albeit from an "opposite" angle, look very closely at your thumb and bring your forearm closer to it. You will see the gap disappear before the fingers touch.
rival
A star with a radius of a million km sends rays from its mantle and not from the center. Therefore, rays came out from the whole disk of the pontiff towards us. This disk is much larger than the planet.
Therefore - there will be no complete concealment.
This is how I understand Albenzo's claim.
rival
I turned on a flashlight in the garden in the dark and covered its light with a tennis ball, as you requested. Then I put the ball about 30 meters away and moved another 30 away.
I did not see the light of the flashlight, but the reflections - from the garden, from the trees, from the air - can be clearly seen.
Miracles
Which Albert, do you mean grandfather Avraham? He is a bit angry with me because I said in the presentation that he was probably wrong about the lack of locality.
Correction - Einstein.
Miracles,
Einstein?
But, how do you explain that both I and Israel did the experiment and under no circumstances did we see the light source when there is a cover in front of it? Why didn't the experiment work for us? Why and how do light rays from a distant planet manage to bypass a large planet that stands in their way and reach us without any reduction in light intensity? How is that possible?
rival
Yes, I agree if it is, in principle. The problem is not in principle. The problem is that the planet will not hide any distant stars.
The main culprit is Israel's friend - Albert.
Israel,
It is not good to do the experiment with a tennis ball.
But how do you explain that it did work for Albantezo and there was no concealment? What flashlight did you use? How far were you from him? At what distance did you put the concealment? Can you describe how the experiment was carried out? It is interesting.
PS - was it in a dark place?
I did the experiment, I didn't find any middle point where the light of the flashlight suddenly appeared.
Full disclosure - instead of a tennis ball I used an iPhone.
rival
I did the experiment, I didn't find any middle point where the light of the flashlight suddenly appeared.
Full disclosure - instead of a tennis ball I used an iPhone.
Miracles,
Even if the planet hides several stars in each image, still if you connect with an imaginary line all the hidden constellations (those whose brightness has decreased a little) in order of hiding, group 1, group 2, group 3... you should get a circular orbit with a star in the center, the one that the planet orbits.
Well, then the planet will pass over a number of stars and we will see a decline in the intensity of their light, and after a few hours or days the planet will pass over another group of stars... So every few days you will see that a new group of stars has decreased in brightness and the previous group has returned to normal brightness again.
Miracles,
"If you take one picture, you won't know anything. The size of a star in your image is exactly one pixel. Choose a black pixel for you - are you claiming that there is a planet there? Maybe there's just no star there?'
But if you took a picture and there were 20 stars in it, and in the next picture you take suddenly the brightness of one of the stars decreased by 30%, isn't that an indication of something? Maybe some planet that just passed by and blocked some of the star's light reaching our telescope?
rival
My point is that the planet will pass over multiple stars in one image. You won't know in what order it happened. This is the information you lose in sampling.
rival
If you take one picture, you won't know anything. The size of a star in your image is exactly one pixel. Choose a black pixel for you - are you claiming that there is a planet there? Maybe there just isn't a star there?
rival
A planet the size of Earth deflects the light by 0.16 millionths of a degree.
The angular size of such a planet at a distance of 10 light years is 6 billionths of a degree.
Now clear?
Miracles,
In the experiment I described to you with the pan, I just wanted to show you that there is no connection between the sample sentence you tried to relate to the subject and between the exposure time and the hiding time of an object, I showed you that the black pan will appear in the final image even though according to the sample sentence you gave you were not supposed to see it at all.
rival
Let's bring your example closer to our topic. Let's move the racket a million kilometers away. Oh, and we'll do it in poor lighting conditions, too. And, with the bat constantly in motion.
Are you still sure we'll see something?
Israel Shapira,
I mean you don't agree with Albantezo's words? You know he has some knowledge and experience in physics, he also said that he performed an experiment similar to the one I quoted you before and the barrier failed to block the light of the flashlight, how do you explain that?
The moon will not hide the sun when it is close to it, only from a certain distance from it.
But after the same distance, the closer it gets to the eye, the more it will hide it.
And this is my argument, that optically there is no such thing as concealment from near and far but not in the middle.
Miracles,
Regarding the part you wrote about the deflection of light due to the distortion of space, I did not understand what you were trying to say there at all.
Miracles,
Again, the sampling sentence is talking about frequency sampling so I don't see how that has anything to do with our case, we're not dealing with frequencies here. Let me ask you a question, you take a picture of the landscape on a bright sunny day with an exposure of 4 seconds, and while taking the picture someone suddenly puts a black frying pan into the frame (which takes up, say, a third of the size of the frame) and holds it steady in front of the camera for one second, do you think you will see or not Is the pan in the final picture you will open?
I say you will definitely see her or at least her silhouette, do you agree with me or not?
Israel,
Leave the explanations (as if any of them understand what he is talking about)... Did you catch what triplex the opponent has? And more with a converter! Oh god…
Light is not a projectile that moves in a straight line and hits a point.
The light is scattered in all directions - unless it is concentrated in a smaller area.
rival
Did you understand that the distortion of light due to the distortion of space prevents any possibility of seeing the shadow of the planet?
rival
The sampling theorem says that the sampling time should be less than half the cycle of the sampled signal.
To catch a flicker of 400 seconds needs a sampling time of 200 seconds. The grief is far from that.
Israel Shapira,
"If the light source is bigger than the barrier, it really won't be covered"
So how do you explain that during a solar eclipse our little moon manages to hide the giant sun behind it?
Israel Shapira,
I'm copying here a number of quotes from Albantezo's messages that I think you missed, please read and tell me if it makes sense to you -
"Here's an experiment you can do with two friends: Go outside at night. You will stand at a certain point and a friend with a strong flashlight will stand 50 meters away from you. You will see it well in the dark. Now look at two different cases:
1. The friend holding the flashlight 50 meters away from you passes a tennis ball in front of the flashlight, at a distance of 10-20 cm. In this case, the tennis ball will block most of the light and you, standing 50 meters away, will actually see a strong decline in the light of the flashlight at the moment of the suit.
2. A third friend stands between you and the friend with the flashlight, 25 meters away from each of you, and passes a tennis ball across the axis connecting you. You will see that the bullet suit will do nothing to the light you see from the flashlight, because at the hiding point (25 meters) the light from the flashlight is already spread over a relatively large area and the bullet suit is really negligible. Of course, in astronomy, where the distances are slightly greater than tens of meters, the problem is even more serious...
Passing a tennis ball near the headlight will hide the light, and passing a tennis ball near your face will also hide the light, but in the middle it will not.'
What do you think? Maybe you will perform the experiment and report the result here?
If the light source is bigger than the barrier, it really won't be covered, but even if the barrier is placed close to the light source it won't.
Bringing the cover to the eye is only good for the cover, otherwise the question arises: if there is cover from near and far, then what is the middle point where it disappears?
Hello, a few light seconds. The hiding is for a good few hours.
Working.
Israel Shapira,
"The middle of the road doesn't match this condition?"
No, because according to what Albantezo claims, the meaning is that the planet will be halfway between us viewers and the star, and that the distance between the planet and the star will be at least a few light years, he claims that in such a situation the planet will not hide the star.
He says (read his message...) that he performed a similar experiment with an LED or flashlight in his home and the barrier he put in the middle of the road failed to hide the light source... Maybe you can reproduce his experiment, do you have a flashlight at home?
If not it is irrelevant.
Israel,
What is the distance between the orbiting stars and the mother star? Is the distance light years?
rival
"Middle of the road" doesn't match this condition?
I say that the planet will hide that distant star, but only for that fraction of a second that it is clearly blocking (actually blocked many years ago) the star's light.
Miracles,
Nyquist's sampling theorem talks about frequencies, what is the connection between this and the exposure time of a camera and the hiding time of the star?
Israel Shapira,
I see that you didn't really follow the messages in this thread carefully, Albantezo talks about a star that is many light years behind the planet, which is many light years from us, he claims that in this situation the planet will not hide the star.
The examples you gave do not match this condition.
rival
I was wrong. A deflection of a billionth of a second is enough... therefore the gravitational deflection is 100 times stronger.
rival
The deflection due to the curvature of space is 10 times that….
rival
Again... we're talking about planets made of atoms. The deviation should not be large - on the order of a hundred millionths of a degree.
rival
Let's assume you're right. The Earth is 12,000 km in diameter. Its speed is 30 km per second. That means it will hide a distant star for 400 seconds.
A typical exposure time of the Hubble is 1000-2000 seconds.
Do you know Nyquist's sampling theorem? Israel, explain to him...
rival
"If we draw an imaginary line between all the stars that were hidden according to the order of their hiding and we find that a circular motion is created around a star, bingo we have found a planet."
Perhaps a quantum computer will be able to weigh all the different movements and different trajectories to reach a meaningful result.
"Of course he will hide"
Why sure?"
Because this is an observed result, according to changing stars ("Cepheids" Elek). Take for example Algol, the devil star. Every two days and three quarters its light dims to such an extent that the dimness can be discerned with the naked eye from Earth, a distance of about 93 light years. The reason is that Algol is a system of 2 stars that orbit the mother star and cause an eclipse that is visible from Earth (you will be able to see it in six months, now you can watch the eclipse only in the southern hemisphere).
"Of course he will hide"
Why sure? Albantezo actually claims that a planet will not hide a star that is far behind it... do you agree with this claim? If so, how do you explain it? (I didn't quite understand Albantezo's explanation, maybe you can explain).
Israel Shapira,
But even today when looking for planets you don't know in advance where they are, so you look at a piece of sky and wait for a reduction in the light intensity of one of the suns in the frame.
Even with the method I propose, you don't know in advance which star will be hidden, so you look at a piece of sky that has enough stars, and wait to see if there will be a hiding of one of the stars, then another hiding of a nearby star, and after another time another hiding of another star that is nearby... if we stretch An imaginary line between all the hidden stars in the order of hiding and we will find that a circular motion is created around a star, bingo we found a planet.
rival
Sure he'll hide, but for how long? And why precisely the same gram of sky that we observe when it has billions of others to hide? How will this prevent us from observing a specific star or moon that we are interested in?
Israel Shapira,
But in the example I'm talking about there isn't just one laser, there are hundreds of billions of laser pencils shining in my direction! So now what are the chances of our little coin hiding one of the lasers?
Did you understand the parable?
Miracles,
1. Let's say all the stars and galaxies behind our planet (the one we're looking for) are moving and moving like crazy in all directions as you claim, how exactly does that prevent the planet from hiding them? When you drive at night next to a big city, and there is a smudge of dirt on your car window that doesn't allow the lights to pass through, will that prevent the smudge from hiding the city lights because they are moving? Why should the shift of the points of light behind the planet interfere with something? I haven't figured that out yet.
2. According to Wikipedia (and also according to Israel Shapira) light can bypass an opaque barrier only when it is smaller than the wavelength of light, are you claiming that what is written in Wikipedia is wrong? And let's say that part of the starlight that hit the planet managed to bypass it, what percentage would that be? 1% ? 5%? Most of the light will still be blocked by the planet, and if not please explain why...
3. I'm actually listening but I don't find much logic in your arguments. Again, with all the light aberrations you talk about we still see billions of stars and galaxies in every tiny piece of sky we look at, so please explain to me, what prevents a planet that is between us and those stars and galaxies, to hide some of those points of light?
elbentzo,
"If you say that there is no difference between a completely dark room and a room with an LED light on..."
Maybe I wasn't clear, ***in all the experiments I did*** a small green LED of the converter came on, but because you emphasized so much that the room must be dark so I waited until it was dark outside and performed the experiment one more time to be sure that the only light in the house was only from The green LED.
I would really like to see an experiment like you did where the barrier fails to block the light of the LED, it seems to me like a kind of magic. It would be nice if someone here would be willing to make a video of a minute or two demonstrating the phenomenon and upload it to YouTube, I would really like to see it. In the experiment I did, the piece of cardboard completely hid the LED (a rectangular LED, but it emits a strong enough light that you can clearly see it from the end of the corridor).
If you have any internet source that explains the effect you're talking about in a simple way plus illustrations for illustration, I'd love to get a link and learn about the phenomenon.
Miracles
I did not understand how the light would bypass the moon because of the smallness of the atoms.
Will the light of his skin become opaque and his electron orbits sealed?
And why didn't you come to Sahbek's lecture in Santa Monica?
https://www.meetup.com/Quantum-Physics-Discussion-Group/events/241128751/
rival
Take a laser pencil and look at it from a short distance (don't forget to wear laser glasses).
If you block it from a short distance with a small coin, the light will disappear.
If you put the coin a short distance from the eye, the light will also disappear.
What happens if the coin is halfway?
If it is right in the middle, will you see the laser itself? Miraculously, no! (Although you will see the edges of the beam hitting the air and from there being projected at you).
If you move the coin along the axis of connection between the laser and the eye, will you see the laser? Button and flower, no!
Does this mean that in the simulation of the celestial bodies you will not see them? Robbery and burglary, yes you will see!
The reason is that if the laser or the coin were in constant motion, what are the chances that you would catch them exactly the moment they are on the same line that connects with the eye?
Alas, extremely low.
Do you accept and understand the analogy?
rival,
First, the purpose of the experiment is to help you see that light is something that spreads through space. If you say that there is no difference between a completely dark room, and a room where an LED light is on but it is hidden in the cardboard far from it - I don't know what to tell you. I just did a similar experiment in the room and it's two different worlds. But since you have no interest in lying, I can only assume that the bulb you used is really, really, weak.
And in answer to your question - no, light rays in space do not move in straight lines, especially not over long distances. But this is not the main reason why a distant planet could not reduce the light of a star significantly enough for us to perceive it - the main reason is that there is no point object here: the telescope is not a point, the source is not a point. You insist on looking at the case of two points (observer and source) and a line connecting them, and assume that if we put something in the middle then there will be concealment. It's just not the right model. The "sun" you see is a sum of photons that were absorbed over a certain area in the telescope, coming roughly from the same area but not exactly. This is an average over a lot of light that left the star and reached roughly the same point in the telescope. Therefore (as I explained earlier) it is not at all a question of concealment in optical geometry but a question of how much change in the light flux the planet makes. And this change fades very quickly with the distance of the planet from the star. Hope this will advance you and maybe more clear than before. I think it's time to retire.
rival
1. The earth orbits the sun at 30 km per second. The sun moves 220 km per second. What is neglected here?
2. The path of light waves is deflected when it meets a barrier and the size of the body connected to the barrier is not important. The detour may be small, but it is not negligible at huge distances.
3. What percentage of the star's light is hidden by a planet 10 light years away? What percentage pass close enough to the planet that they will reach us? Our sun emits light in a measurable way. The calculation I suggested that a planet would deviate as much?
rival
1. The earth orbits the sun at 30 km per second. The sun moves 220 km per second. What is neglected here?
2. The path of light waves is deflected when it meets a barrier and the size of the body connected to the barrier is not important. The detour may be small, but it is not negligible at huge distances.
3. What percentage of the star's light is hidden by a planet 10 light years away? What percentage pass close enough to the planet that they will reach us? Our sun emits light in a measurable way. enough. .. if you don't want to listen 🙂
Israel Shapira,
We see tens of billions of suns in the sky in every direction we look, so I guess there are enough suns and distant galaxies that the planets we're looking for can hide...
Miracles,
I don't understand why you get upset and take it so personally, I'm not trying to dismiss anything that doesn't fit my opinion, I'm just trying to understand what's right and what's not. I detailed and reasoned about each point you raised in a fairly objective way in my opinion, and wrote down why I don't think it's relevant, I even agreed with you about one of the points.
1. You say that the movement of the star (the one behind the planet) is noticeable and not negligible, no problem, but how does this rule out the idea that the planet will at some point hide that star when it and the planet align on the same line that reaches from the star to us on Earth? In what way is this supposed to interfere? And yet, I think that when we look at very distant stars, as far as we are concerned, they are almost stationary and do not move, especially when talking about a photo that lasts only a few minutes or a few hours. When you look at the moon at night from the balcony of your house, do you manage to notice its movement? I highly doubt it…
2. "I want to tell you a secret, but don't reveal it to Israel! The planet is made of really, really small atoms. …. Therefore, they also create a bypass. But six. .. it's just between us"
I really couldn't understand this genius sentence... Are you saying that light manages to bypass a huge mass of atoms stuck together, in the shape of a planet, because each one of them is really, really small? According to your claim, we were supposed to be transparent and the light was supposed to pass through us, right? Maybe Israel Shapira wants to say something about it? 🙂
3. "Our sun visibly deflects starlight due to the curvature of space. The sun weighs a million times more than a planet.
This is true, but again I don't understand how this prevents a planet from hiding stars that are in the background? Among all the light rays that come from distant stars and are modulated by large masses to the right and left, up and down, is there not a single star whose light rays hit the planet exactly and therefore do not reach us at a certain point? Your argument is really incomprehensible.
My logic says that a barrier to light from a certain direction, the moon for example, will cast a "shadow" on the Earth and hide what is behind it, including planets and suns.
But this is only relevant for ancient light that hit the barrier many years ago (4000 in the case of Kepler-1625b), the chance of which is also not small right now.
Olvers claimed at the time that the night sky should be as bright as the day sky, a.k.a. the Olvers Paradox. The solution, big bang and expansion.
rival
The fact that you dismiss everything I say because it doesn't fit in your opinion is beautiful. That doesn't make it true.
In a planet's year there is a non-negligible movement of the star, because the star is a point. That is, its size is far below the resolution of any existing telescope.
I want to tell you a secret, but don't reveal to Israel! The planet is made of really, really small atoms. …. Therefore, they also create a bypass. But six. .. it's just between us.
further. Our sun visibly deflects starlight due to the curvature of space. The sun weighs a million times that of a planet. I will leave it to the intelligent reader to calculate how far away distant planets are. ..
rival
The fact that you dismiss everything I say because it doesn't fit in your opinion is beautiful. That doesn't make it true.
In a planet's year there is a non-negligible movement of the star, because the star is a point. That is, its size is far below the resolution of any existing telescope.
I want to tell you a secret, but don't reveal to Israel! The planet is made of really, really small atoms. …. Therefore, they also create a bypass. But shhhhhh. .. it's just between us.
further. Our sun visibly deflects starlight due to the curvature of space. The sun weighs a million times that of a planet. I will leave it to the intelligent reader to calculate how far away distant planets are. ..
PS - the two previous messages are different from each other, their beginnings are similar so it may confuse and look like it is a duplication of the same message, it is not.
I performed the experiment one more time now, when it was already dark outside, to be 100% sure that I hadn't previously missed some ray of light that might have accidentally penetrated under one of the blinds without me noticing, and I also made a new piece of cardboard that I made sure was exactly the thickness of the LED no less and no more. And again, when the house is completely dark I got exactly the same result as before, the thin piece of cardboard completely covers the LED and from a distance of 11 meters you can't see it at all when it is placed halfway between me and the LED.
Beyond that, I would be happy to understand the descriptive logic behind this claim that the piece of cardboard (or the planet if we return to our subject) will not hide the light source that is far behind it. Doesn't the light that travels from the light source to our means of observation travel in straight lines? If so, how is he supposed to get around the opaque obstacle that stands in his way?
Israel Shapira where did you go? You have nothing to contribute to the discussion?
I performed the experiment once more and again got the exact same result. I darkened the whole house, closed all the blinds, curtains, doors, even covered the digital display of one of the devices in the living room area so you wouldn't be disturbed. I stood at a distance of a little more than 11 meters from the green LED of the converter, when in the middle between the converter and me I again placed a thin and long piece of cardboard as thick as the LED. And again, when I positioned myself at the proper angle where the edge of the piece of cardboard is right in front of the LED, the green LED disappeared and I didn't see it at all.
Anyone who wants is welcome to repeat the experiment himself at home and see.
Miracles,
Of all the points you raised, I think only the point of a long exposure time is really relevant, and I already addressed this in the first messages I wrote on the subject. Indeed, if the time of the eclipse (hiding) of the star by the planet is too short relative to the exposure time of the photograph then it will really be difficult to detect it.
Regarding the sparseness of the stars in the background, it seems to me that there are actually enough points of light in the background (and as mentioned, distant galaxies can also be used as points of light that the planet can hide...) and even if the planet does not hide every single one of them continuously, it is enough to have a point of light hidden once in... and after a few Individual obscurations we can already recognize that the obscurations form a pattern of a circle around a star that is in the center.
Regarding the movement of the planets and the stars - irrelevant in my opinion, you will still see a point of light that moves, and suddenly disappears when the planet is exactly between us and that point of light, what is more, at such distances and with the relatively short photography times, the movement of the stars and galaxies is almost imperceptible.
Regarding the deflection of light, as Israel Shapira said and also according to Wikipedia, light can only bypass a barrier if the barrier is smaller than its wavelength, which means that it is really not relevant to our matter, a planet is much too big an obstacle for light to be able to bypass it.
Regarding the light that is bent according to the theory of relativity, this is only relevant if there are really massive bodies between the star and us, and even if so, there will still be enough suns (or galaxies) in the background for the planet to block the path of light from them to the earth.
In addition, elbentzo claims that if the sun is far behind the planet then the planet will not be able to reduce the amount of light that reaches us from it, but I have not seen anywhere that he explains why this happens. Doesn't the light coming from the star travel in straight lines? If so, how does he manage to bypass the planet? This somewhat contradicts the high school physics I know...
rival
It's actually consistent. ..
I think in principle your idea is good.
Practical - no.
All paper, a planet will hide a distant star.
In practice - both the planet and the star are points in the sky. Assuming, which I think is wrong, that there are so many stars that there will always be a star hidden by the planet. But - the planets and stars are in motion. For example, the planets circle the center of the Milky Way.
The second problem is indirect. In classical physics, light bends slightly when it passes by an object. Israel is right that it is little but at huge distances I think it is enough to prevent measurement of such concealment.
In the theory of relativity, light is curved when passing near mass (to be precise, space is curved...). This will also mean that there will be no hiding of the star.
Another problem is that the eclipse time will be very short. When a telescope photographs stars, the exposure time is hours, not fractions of a second.
I think your idea is beautiful! But, I don't think there will be any measurable effect.
Regarding Picasso, perhaps it is more correct to say a painting, rather than a picture.
elbentzo,
I admit that I cannot understand your explanation although I appreciate that you are trying to explain.
You claim that what we see is not the star itself but the light it emits, but this is actually true of every object we see, isn't it? When we look at a street lamp or at the headlights of a car driving in front of us, we see the light emitted from them, and when we look at a Picasso picture in a museum, we see the light that hit the picture and returned to our eyes, don't we? So we always see the light reflected from objects... whether they created it themselves, or whether they reflect light created elsewhere.
You say that the angular size of the stars we see is much larger than their true angular size, but why? Don't the rays of light emitted by the star move in straight lines?
When it gets dark I'll do the experiment with the LED again, but I already estimate that even if I see some greenish glow at the edge of the cardboard that hides the LED, it will still block 99% of the light compared to the situation without the cardboard that hides.
Isn't the wavelength of light a little too small for bypassing stars?
rival,
What you see in the sky is not the star. You see a certain amount of light it emits. Because it's far away, it looks pretty small in the sky, but that doesn't mean you see the star. What is important to understand is that all celestial objects themselves (whether it is a moon with a radius of 1000 km, a planet with a radius of 5000 km or a star with a radius of one million km) have an angular size of literally zero on the surface of our sky. They are invisible. The reason stars can actually be seen (unlike planets and moons, unless they are really, really, really close to us) is because of the light they emit and its spread, which causes their angular size on the sky to be much larger than their actual size (but still quite small because they are far away).
What I am trying to explain to you is that a planet does not hide the sun itself. It only blocks part of the light it emits, the sum of all this light (within the angular key of the telescope) is what you see as the "star" in the sky. If the planet is not very close to the sun, it will not affect the light emission significantly. This. Throughout all the many responses you just miss the point that what you see is not the star, but a certain amount of light it emits. Therefore, one should not ask whether the planet hides it as in optical geometry (straight rays that connect point objects), but how much it changes the amount of light it emits in our direction. This change is relevant only when the distance between the sun and the planet is small.
I'm not sure if I can explain it more clearly. If my explanation is not good for you, there are lots of internet sources (or you can perform the experiment I suggested, or the experiment you suggested but in a completely dark room where the light from the LED is not absorbed by other lights).
Miracles,
I don't understand, do you change your mind every second?
Earlier you told me: "In principle, the planet can cause a complete eclipse of that star, but it will be a one-time event... A planet will completely hide any star that is very far from it.'
And now you say it's not possible? And what do you mean when you say deflection and relativity? How does this prevent a planet the size of Earth from hiding a distant star 20 thousand light years behind it?
rival
One of the things you ignore is bypassing. And the second thing is the theory of relativity. The result is, in my understanding, that a planet light years away from a star and also from us will not have a noticeable effect on the amount of visible light.
In practice, you are trying to hide a point with a point. And you don't have so many points (stars) that you can ignore it.
elbentzo,
I completely understand what you're saying about the angular size of the star that the planet is obscuring, and obviously it will subtend a smaller angle from it as it moves away.
But I don't understand how this is relevant to our issues, after all what interests us as viewers here from Earth is only the spatial angle ***at which*** we see the same distant star (sun) and not how much light it emits backwards, to the sides, or at all kinds of angles in which the light from it does not reach our means of observation.
You will probably agree with me that the further that star is from us, the smaller the spatial angle at which we will see it. At a certain distance it will look like a shekel coin (in its angular size) and at a much greater distance it will already look like a small dot to us, that is, with a much smaller angular size.
Now my question is this, if there is a planet (moon) of a certain size, and far away (really far) behind it there is a star, is it not possible that the angular size in which we see that planet, will be the same or even greater than the angular size of that star as we see it here from earth? If so, why wouldn't she hide him?
(PS - notice that Nissim also agrees with me that this is possible: "A planet will completely hide any star that is very far away from it")
And one last thing - in the experiment you did, the light of the LED was simply swallowed by all the light you have at home. Repeat the experiment in total darkness. You will see that if the cardboard is close to the LED it obviously hides the light, but if it is far away you will still see green radiation around it. Maybe in your experiment the cardboard will block a large part of the light even when it is far away, but that is simply because of the scales - if the cardboard was small in relation to the LED (as planets are small in relation to the light emitted from stars) and the distances were astronomical, then you would not see this blocking either.
And by the way - the less pointy your flashlight is, the better, because even a star does not emit light in a directional manner. Rather, a small, directional flashlight will fail in the experiment I proposed (as I explained, the dispersion of light is small).
rival,
I already explained to you twice. You think of everyday objects that hide other everyday objects. These are objects of fixed size. But a star, or any light source, is not an object of constant size. The light it emits increases as you move away from it, so the further you move away from it, the harder it is to hide. I also explained to you exactly how to see it mathematically - look at the angular size of a planet at some radius (say 5000 km) when it is at a distance r from the light source. You will see that the spatial angle it occupies decreases as r increases. That is, she hides less. It's very simple.
Elisef Kisman,
You must be reading the comments, what do you think about it?
Elisef Kosman,
You must be reading the stuff, what do you think?
elbentzo,
I don't have a small flashlight available for the experiment you suggested (I only have a few large non-point flashlights) but I did a similar experiment that I think parallels your experiment. There is a television in the living room at home and next to it a converter box with a tiny light bulb (LED) that glows green. I cut a thin strip from a piece of cardboard (from a cornflakes box) that was exactly the size of the LED, and attached it to a chair in the middle of the hallway (the hallway is quite long...). Now I was standing at the end of the corridor, I closed one eye and with the other eye I clearly saw the green point of light of the converter. I moved a little to the sides, up and down, until as expected the edge of the thin piece of cardboard completely covered the LED and completely hid it.
So first of all the experiment showed me that the idea is possible, but regardless, explain something to me logically, if there is a planet that is large enough to hide the sun it orbits, to such an extent that we can measure the reduction of light that is created during the hiding, then why that planet cannot hide A star much further away that for us (from our vantage point on Earth, or from the Hubble telescope) is even smaller and fainter than the star that planet orbits? Or in other words - if the planet manages to hide a point of light (its sun) why won't it manage to hide an even smaller point of light that is behind it in the background...?
Miracles,
1. "Let's simplify a lot more. A planet will completely hide any star that is very far away from it. Think, we don't need exact defects. It's better than your idea, because it has a much higher probability.'
But it sounds to me exactly the same as the idea I'm talking about from the beginning of the thread, a planet that hides one of the distant stars that are far behind it. How is your idea different from mine?
2. "I still maintain that the probability is zero. At these distances the celestial bodies are points. After all, this is only our galaxy and our galaxy has a finite number of stars. Because the stars look so small, I don't think their density is high enough to have a large number of eclipses.'
I am not at all sure that you are right and that the density of stars in our galaxy is not high enough for it to work, another thing is that these do not have to be only stars in our galaxy, also billions of distant galaxies that are in the background of the photo, and each one is a point of light or a spot of light in the background, they can also be used As an additional light source that the planet can hide when it passes through the same area.
3. "And regarding the ellipse. Even if there are defects, they will be at different times, because at great distances it takes long and different times to reach us. So what will you see? that once in a long period a distant star will weaken for a few minutes. It seems very problematic to me."
Your comment is not clear, first of all it is clear that the defects will be at different times, that is the whole idea of the method I proposed, and what does the distance and the time it takes for the light to travel matter? For a whole day you took a sequence of photos with a difference of a second between photos, then you start going through the photos in order and comparing every two consecutive photos. In one picture you see a star (or a distant galaxy) in a certain area and in the next picture suddenly that point of light disappears! You continue to go through the photos in the order they were taken, and then you suddenly see that the point of light that was hidden before is now illuminated again, but another point of light, which is right next to it and appeared before, is now hidden!
And so as you continue to compare the images, you recognize a clear pattern, every few minutes another point of light that appeared in the previous images dims or disappears, and the sequence of "disappearances" (hiding) creates a clear path that is shaped like a circle, with one star in the center that appears in the entire sequence of images! (the star that the planet orbits).
rival
Let's simplify a lot more. A planet will completely hide any star that is very far away from it. Think, we don't need exact defects.
It's better than your idea because it has a much higher probability.
I have no idea, every time you upgrade Warpers something happens.
rival,
In what you sent the plane passes very close to the camera. There is symmetry between the light source (the flashlight in the experiment) and the observer (you in the experiment). That is, passing a tennis ball near the headlight will hide the light, and also passing a tennis ball near your face will hide the light, but in the middle it will not. This is why the moon can strike the sun - because it is very close to us in relation to it. I think it is very clear if you try to understand the explanation I gave about the angular size in the answer before the experiment.
And I explained to you why a tennis ball that passes exactly on the connecting line between you and the flashlight will not hide the flashlight. Because what you see is not the flashlight. You see the light that the flashlight emits, and that light spreads out (for a star that emits light isotropically, it spreads out over a sphere). For there to be a significant eclipse, the obscuring object must have a very large angular size on the surface of the sphere, that is, either close to the occulting sun, or close to the observer (in which case it will block the observer's angular key).
If you don't believe, do the experiment. He is really simple. The explanation doesn't require any complicated physics or math either.
rival
I still maintain that the probability is zero. At these distances the celestial bodies are points. After all, this is only our galaxy and our galaxy has a finite number of stars. Because the stars look so small, I don't think their density is high enough to have a large number of eclipses.
And about the ellipse. Even if there are defects, they will be at different times, because at great distances it takes long and different times to reach us.
So what will you see? that once in a long period a distant star will weaken for a few minutes. It seems very problematic to me.
Avi Blizovsky,
Why don't links within messages become clickable like they used to? This is very inconvenient, can you please fix it?
Miracles,
'So in principle the planet can cause a total eclipse of that star. And if suddenly a star becomes very weak, what information does this give about..."
1. So first of all I see that you align with me and agree now that a small planet can indeed hide a huge sun that is tens of thousands of light years behind it, in the previous messages you claimed that it was impossible.
2. "But it will be a one-time event, and not just an extremely rare one." After all, the planet does not revolve around the same star, and all the heavenly bodies are in motion."
But if that small planet (planet) hides one sun that is far behind it, in the background as far as we are concerned as observers, and immediately after that it hides the sun that is adjacent to it in our line of sight, and immediately after that another sun that is nearby, and we continue to follow this path of obscuration and find that its shape is a circle (or an ellipse) and in the center of that circle there is a star (probably the star that that planet orbits), wouldn't we have a good reason to think that it might be a planet that orbits the same sun?
elbentzo,
See this shot:
https://ak8.picdn.net/shutterstock/videos/15582904/thumb/11.jpg
A small plane (a tennis ball in your example) hides a huge sun that is much bigger than it, how does that fit with your explanation? If the tennis ball passes between me and the guy with the flashlight, exactly on the line between my eye and the flashlight, I see no reason why it wouldn't hide the flashlight completely.
rival
Let's take a planet with a diameter of 10,000 km at a distance of 10 light years. If we find a star with a diameter of 200,000 km, at a distance of 200 light years, then in principle the planet can cause a total eclipse of that star.
But it will be a one-time event, and not just extremely rare. After all, the planet does not revolve around the same star, and all the heavenly bodies are in motion.
And if a star suddenly becomes very weak, what information does this give about that planet? Isn't it more likely that maybe a black hole caused the flickering, or maybe a blockage in the carburetor of that planet?
Here's an experiment you can do with two friends:
Go out at night on the street. You will stand at a certain point and a friend with a strong flashlight will stand 50 meters away from you. You will see it well in the dark. Now look at two different cases:
1. The friend holding the flashlight 50 meters away from you passes a tennis ball in front of the flashlight, at a distance of 10-20 cm. In this case, the tennis ball will block most of the light and you, standing 50 meters away, will actually see a strong decline in the light of the flashlight at the moment of the suit.
2. A third friend stands between you and the friend with the flashlight, 25 meters away from each of you, and passes a tennis ball across the axis connecting you. You will see that the bullet suit will do nothing to the light you see from the flashlight, because at the hiding point (25 meters) the light from the flashlight is already spread over a relatively large area and the bullet suit is really negligible. Of course, in astronomy, where the distances are slightly greater than tens of meters, the problem is even more serious.
rival,
for a reference system. Suppose you are sitting on a sun somewhere in space. The sun emits light isotropically, that is, on the surface of a sphere. If there is any body (for example, a planet) very close to you, it will block a considerable part of the light you emitted (because its angular size on the surface of the sphere will be large, because the radius is small). If there is the same body but it is far away from you, it will hardly block the light you emitted because at a large radius, your ball of light is very large and the angular size of the body will be small.
Miracles,
You say that the billions of stars that are in the background, behind that planet are visible from Earth as small points of light, what prevents the planet from hiding them? I haven't figured that out yet.
rival
I explained - because for us, the distance between the planet and the sun is negligible. Therefore - the angular size seen by each one is relative to the diameter.
If you are close to the planet then it will appear larger relative to the sun.
Your method won't work. The reason is that the stars are so far away that their apparent size is smaller than each "pixel". That is, even in the most powerful telescope, the stars still appear as points of light.
There are exceptional cases, like the famous Beetlejuice, but that's only because it's obnoxious in size and not that far away.
Therefore - the probability that a planet will hide a distant star is zero.
I see no way to discover a hidden planet orbiting a dark sun at a great distance.
Miracles,
I didn't understand why you claim that the last paragraph I wrote is wrong. But let me ask you a question, if the sun that the planet orbits was turned off, that is, it would not emit light - would it be possible to discover the planet that orbits it, using the method I proposed? (that is to check which other, distant, suns that are in the background it hides during its course).
rival
The "eclipses" we see are something like we see the passage of Venus over the Sun. By the way, such a passage was used to measure the distance to the sun, in which James Cook participated, on this voyage he reached Australia.
What you see is a small weakening in the intensity of the sun, the weakness that is relative to the ratio of the diameters of the planet and the sun.
why is it? Because at great distances, the rays of light coming from the sun are parallel.
The distance between a planet and the sun is hundreds of millions of kilometers. The distance from us to the sun (and also to the planet) is measured in tens of trillions of km!!
Therefore - your last paragraph is wrong.
Miracles,
"An eclipse is caused by the observer's proximity to that celestial body that hides the local sun"
Are you claiming that all the moons we discovered through this method were close to us, the observers?
"For you to see an eclipse from a distance, the celestial body needs to be the same size as its sun"
But the moon is certainly bigger for us as viewers compared to the sun which is far behind it in the background, say 20 light years further away, so why wouldn't it hide it? And billions of more distant suns that are in the background?
rival
An eclipse is caused by the proximity of the observer to that celestial body that hides the local sun.
In order for you to see an eclipse from a distance, the celestial body needs to be the same size as the Sun which is not.
Avi,
But the fact is, we manage to photograph these stars (billions of which are in the background of the solar system we are trying to study), and logic says that when that small moon passes between us and these suns, it doesn't just reduce their light, but more than that, it completely covers them. I find it hard to believe that this cannot be detected, even in long exposure photography. And even if it will be difficult to detect this by eye, a computer program will surely be able to detect the small differences statistically (statistically, there will be a thin "strip" in the image where the light intensity of the windows in the background is a little weaker than in the rest of the image).
Avi,
But the fact is, we manage to photograph these stars (billions of which are in the background of the solar system we're trying to study), and logic says that when that small moon passes between us and these suns, it doesn't just reduce their light, but more than that, it completely covers them. I find it hard to believe that this cannot be detected. Even in long exposure photography, and even if it will be difficult to detect this by eye, a computer program will probably be able to detect the small differences statistically (statistically, there will be a thin "strip" in the image where the light intensity of the windows in the background is a little weaker than in the rest of the image).
According to what I understand, the distances are so great that you can hardly see this flickering, and therefore you can only discover satellites (planets / moons) that cross our line of sight, and perform this partial eclipse, and they also have to be large enough for the flickering to be significant and measurable, there are probably many more Very many that we can't find out.
I have a question, usually the method of checking the dimming of the star's light is used (as demonstrated in the article) to conclude if one of its moons has passed by, in our line of sight. The problem with this method is that if the planet orbits the star in an orbit that does not cross the line of sight that is between us and the star (that is, its orbital disk is not perpendicular to the Earth) we will not be able to identify it using this method. Another problem is that the star's light is "dazzling" and if the moon is small it will be difficult to detect a reduction in light intensity when the moon passes by.
So my question is why not use the many stars in the background to identify the moon? After all, when the moon goes around its sun, it hides during its movement a lot of other stars that are further away in the background, and their light is much weaker so that the effect of the moon when it passes by them will be much greater in my opinion.
And if the photograph is a long exposure, then it may be possible to recognize its "trail", meaning a thin band or a kind of "ring" where, on average, the light of the stars in the background is slightly weaker than the rest of the stars.
what do you think?
I am amazed by this ability to estimate and measure a body so far away just by the twinkling of a star...
to Shimon,
The only example we have so far is our solar system, where 184 moons are currently known, although many of them are very small. 19 of them are large enough to take a spherical shape. Among the terrestrial planets in the inner solar system, the only significant moon is our own, while Venus and Mercury have no moons, and Mars has two small moons, which may be asteroids captured by its gravity. Most of the moons are then around the more distant gas giants.
I probably didn't emphasize it enough in the article, but the fact that no moons around planets outside the solar system have been discovered so far is quite simple - the technology is not developed enough to detect their weak effect in dimming the starlight.
Even the current "discovery" has not yet been verified, because three eclipses are not enough to prove it for sure, so the researchers will make another observation in October with the Hubble, which is a more powerful telescope than Kepler.
Another interesting thing I mentioned in the article is the fact that this particular moon, if it does exist, is much larger than any moon we know of in our solar system. Its size is like that of Neptune (which is 4 times larger than the Earth). If the moon does exist, the fact that it is the first extrasolar moon to be discovered would not surprise me, because its large size makes the discovery easier. This was also the case with the first extrasolar planets, which began to be discovered in the 90s - then a completely new breed of planets known as "hot Jupiters", planets the size of Jupiter that are very close to their star, so that the duration of their "year" was first discovered lasts a few days. In this way, their detection by indirect detection methods (or by the eclipse method described in the article, or by the method that looks for the gravitational influence of the planet on the star itself), becomes much easier.
Perhaps when technology develops, with telescopes like James Webb's, we will be able to locate smaller moons. Although, unlike Kepler, Webb will not be making long-term observations to find extrasolar planets.
It is also worth adding that such moons have the potential to increase researchers' "bank of targets" for the search for extraterrestrial life. Moons in our solar system have already done so, such as Jupiter's moon Europa which probably has a subsurface ocean. Outside the solar system, however, moons may be very different from what we are familiar with, perhaps a bit like the science fiction movie "Avatar", in which the moon Pandora orbits a gas giant.
Sorry for the ignorance, but is a moon a rare thing? If so why?