European astronomers have discovered a planetary system that contains at least five planets orbiting the star HD 10180. The findings suggest that there may be two additional planets in this system, one of which has the lowest mass ever found for a planet
There is another star similar to our Sun with an interesting family of planets orbiting it. This system may be the most similar system to our solar system that astronomers have found so far. European astronomers have discovered a planetary system that contains at least five planets orbiting the star HD 10180. The findings suggest that there may be two more planets in this system, one of which has the lowest mass ever found for a planet.
"With a high probability we have found the solar system with the most planets discovered so far" says Christoph Luvis who led the group. "The significant discovery also clarifies the fact that we are entering a new era in the study of planets outside our solar system (exoplanets) - the study of complex star systems and not just individual planets. Tracking the motion of the planets in the newly discovered system shows complicated gravitational relationships between the planets and gives us an understanding of the expected evolution of the system.
Another thing that is very interesting about the new solar system is that the distances between the planets and their sun follow a consistent pattern as we can see in our solar system as well. "The consistent pattern can be a hallmark of the formation process of planetary systems of this type," says group member Michel Mayor.
The sun HD 10180 is located 127 light years from our solar system in the direction of the southern constellation Hydrus. The five planets that have been observed with certainty so far are about the size of the planet Neptune, that is, between 13 and 25 times the mass of Earth. The time the planets orbit their sun ranges from six days to six hundred days. The distance of the planets from their sun ranges from 0.06 to 1.4 times the distance of Earth from the sun (astronomical units).
"We also have good reasons to believe that there are two more planets in the new solar system" says Lovis. One of the planets is supposed to be Saturn-like (meaning at least 65 Earth masses) with a 2,200-day rotation around the system's sun. The other planet would probably be the least massive planet found outside our solar system and would be about 1.4 Earth masses. This planet is very close to its sun about 2% of the distance between the earth and the sun. One "year" on this planet would be equal to 1.18 Earth days.
"The object (the nearest minor planet) only causes its sun to vibrate at a speed of 3 km per hour - lower than walking speed - and this speed is very difficult to measure," says team member Damien Sigrensen. If the theory of the presence of this small planet is confirmed, the object will be another example of a rocky planet similar to the planet Koro 7b (Corot 7b).
The research team used the HARPS star detector spectrograph attached to ESO's 3.6-meter telescope in La Silla, Chile and conducted observations of the star HD 10180 for six years.
The newly discovered planetary system around the star HD 10180 is special for several reasons: With at least five Neptune-like stars orbiting the sun at a similar distance to Mars, this system is denser and more massive than our own solar system in its interior. Furthermore, the system does not have a gas giant like Jupiter and in addition all the planets have an almost circular orbit.
With the announcement of this solar system the total number of extrasolar planets found is 472.
- Link to article
- For the news in Universe Today
- For information on the European Southern Observatory ESO website
Courtesy: Bows from Rotter.net
Translation: Darwin from Rotter.net
21 תגובות
I wanted to ask if there is no air in space, then what is the problem with flying a fast spaceship to an unknown place?
Avi,
As for your question "is the sun a relatively large star":
The question of what an average star is is a problematic question - I will explain why:
Suppose there are 400 stars of mass 0.01, 200 stars of mass 1 and 100 stars of mass 100.
The median star will indeed have a mass of 0.01, but most of the mass will be in the heavy stars with a mass of 100 and thus if you are a hydrogen atom most of your chances of finding a heavy star - that is, they are more dominant.
Also, there is another problem with this question -
Suppose a star of mass 1 and a star of mass 3, it is clear that they are two completely different stars in their properties and structure, therefore it is appropriate to treat 3 as greater than 1, on the other hand two stars of magnitude 100 and 102 are almost completely equal even though the difference is the same.
The usual way to present the mass distribution of stars is as f(m)=Am^-a
When
f is the number of stars between mass m and mass m+dm
A is constant (so that the integral on the function will be the number of stars or 1 - depending on how you want)
The solution to your question actually sits in a
If it is greater than 2, most of the mass is in the smallest stars (there will be more stars between 0.1 and 0.2 mass than between 10 and 20), and if it is less than 2 then vice versa.
Apparently it is slightly larger than 2 - that is, most of the mass is in the small stars, but it is claimed that this power law changes for about half a solar mass and becomes smaller than 2. If this is indeed the case, then the average star is about half the mass of the sun, and as Michael pointed out, the sun is a somewhat larger star than average.
In any case, the mass of stars has limitations -
The smallest possible star has a mass of about 8% of the mass of the sun (with less than that, nuclear processes will not start) and the largest possible star is on the scale of hundreds of solar masses (since in such large stars, instabilities start to develop related to the fact that the radiation pressure in them is very large).
See
http://en.wikipedia.org/wiki/Initial_mass_function
Let's say that right now the size of our sun is close to average. Since we keep searching all the time, so this figure can change up or down.
Just as we are currently the only inhabited planet in the known universe. That is until we find that there are other planets inhabited by life.
The funny part about our whole thinking that there is no life on other planets is - we haven't found it. Apparently the conclusion should have been the opposite: in the only sample we have - the Earth, we found life. Therefore, the matter should be looked at positively and not negatively, that is, there is a high probability that in almost every solar system in the universe - there is life.
Thank you very much Michael, your response is really interesting and enriching.
6 And Daniel:
1. Here is a table of the stars closest to us: http://en.wikipedia.org/wiki/List_of_nearest_stars
2. We discover the composition of stars by analyzing the radiation spectrum coming from them. Each material emits radiation at known frequencies and we are able to identify the spectral signatures of the various materials.
3. We do not see most of the planets for several reasons. Mainly because they are very small and the amount of light reflected from them is small. The planets were indeed discovered, located, using a number of different techniques and usually not through direct sight of the planet itself. The prominent techniques are based on the analysis of the orbital changes created by the planet's gravity in the orbit of the parent star and on eclipses where the planet passes the lines of sight between us and the parent star (ie - identifying the planet through its shadow).
4. I once read that the size of the sun is average. Maybe a little higher than that. I can't find the source right now.
5. Any body that is not at a temperature of absolute zero - emits radiation. The question is only at what frequency (energy) and at what intensity. If you were to move the earth away from the sun, it would continue to emit radiation until it cooled completely. In fact - the statement that the Earth reflects sunlight is also not completely accurate. A large part of the radiation emitted by the earth is radiation emitted by the materials on the earth's surface as a result of the sun's radiation hitting them.
I wonder what the figures are for survival on the surface of the stars in this galaxy?..
For 6,
I think I know some of the answers to your questions, but not XNUMX% sure,
2. It may be possible to know based on a sample of the type of material in the star and the mass of a small unit of the type of material and based on the circumference of the star, it is possible to find out through physics and math calculations, the data in Mogul.
4. In my opinion, in relation to the other stars in other galaxies, the sun is a little below average.
5. Our earth only reflects light, and does not generate radiation itself.
Well then I'm moving there…. Workers needed to build my new house!!! Happy holiday!
To Mickey - the middle star in Orion's belt is not the nebula itself but a star in itself. "Beneath it" appears the nebula - very difficult to recognize in the city except on a very dark night.
As for the Andromeda galaxy - it can definitely be seen from Israel as well as other "nearby" galaxies.
Artificial satellites and the like are very difficult to detect in the night sky since they move very quickly in relation to the self-rotation of the Earth, the exception being the International Space Station which can be detected by rapid flashing and a relatively quick crossing of the night sky.
As for comets and asteroids - they cannot be identified with the naked eye unless they are really close to the Earth or the sun (in the context of the comets) because then they spread the infamous trail.
In general - it is easy to identify and distinguish between the planets of our solar system and the other stars of the night: our planets reflect relatively strong light compared to the other stars in the sky and they do not "sparkle". In contrast, the other stars (those distant suns) do twinkle.
To A. Ben Ner and Aryeh,
True, not every "star-like" thing in the sky is really a star/sun, but most of them are. Galaxies are indeed large, but they are very far away from us, so it is very, very difficult to see them with the naked eye (no - this is not a curse). There are still a few that do - including the Large and Small Magellanic Clouds, which unfortunately cannot be seen from Israel (mainly from the southern half of Israel) and the Andromeda Galaxy (M32). But we are more likely to confuse a nebula with a star, since there are more nebulae in the sky that can be seen than galaxies. A common example is the Orion Nebula located in Orion's Belt (yes - the North Arrow). The line of the arrow is supposedly made of 3 stars, but the third star is not a star, it is actually the nebula. Other objects mistakenly identified as stars are satellites that do not move in the sky (yes there are such - usually spy satellites) or that move slowly, comets, and possibly asteroids although this is very unlikely because they are very small and usually far away (I hope...).
Dear troll, when time is not limited even an event with an extremely low probability will occur.
For a friend, there is no doubt that he intervened in our favor, after that he went to rest in Las Vegas and has not returned to this day.
The chance of life is so low that there must be someone (God) who interfered with the chances in our favor! This entire site is a testimony to the Creator, blessed be His name
So what do you say there is no chance of ever getting there aha? Never. Just look far far away…..
to Aria
I believe that some of the stars visible to the eye are galaxies.
First of all thank you.
1. Which planet (Sun) is closest to the planet "Earth"?
2. How is it possible to know the exact composition of a star that is so far away from us?
3. Is the reason we don't know about many "planets" (relatively) because of the strong glow of the star around which they revolve?
4. Is "our" sun a relatively large "star"?
5. Does the planet "Earth" also produce its own "glow" in one process or another, or does it only reflect light?
Thanks in advance.
Number 4 is correct.
Even more confusing is the name given to Mercury "Hema planet". It is not a star, and our sun is called Hema. Our sun could be called "the planet of Mercury".
I think we need to find a new name for the term planet. The use of a star for a self-radiating object and a planet for a planet is a bit confusing
Father - yes, every star visible to our eyes is a sun, with the exception of planets of our solar system, such as Venus, Mars, Saturn, Jupiter, whose position in relation to the star map changes.
Is every star you see at night actually a sun?
Well, that means there is a chance that there is life there..like ours..but one thing I don't understand is there is no way to get to such places in life aha?
127 light years means it's impossible to ever get there..
in mass...