After we moved radio and television transmissions to cables and fiber optics, we became undetectable to aliens, but they may be able to detect the lights of night-side cities even from a distance, two astrophysicists suggest looking for alien cities this way
In the search for extraterrestrial intelligence, astronomers look for radio signals and extremely short laser bursts. In a new study, Avi Leib (Harvard-Smithsonian Institute for Astrophysics) and Edwin Turner of Princeton University propose a new technique for detecting aliens: looking for city lights.
"The search for extraterrestrial intelligence is supposed to be complicated, but will not require additional resources (beyond the search for the planet itself AB), and if we succeed, this will signify a change in our perception of our place in the universe," says Leib.
The rest of the methods for SETI (Search for Extraterrestrial Intelligence) rely on the assumption that the aliens will use technologies similar to ours. This is reasonable because an intelligence that will develop in the light of the nearby star is expected to also use artificial lighting that will be turned on during the hours of darkness.
How easy would it be to observe city lights on distant planets? It is clear that the light will be distinguishable from the glow of the parent star. Leib and Turner suggest looking for changes in lighting from an extrasolar planet as it moves around its star.
As the planet orbits its sun, it goes through phases similar to those of the moon. When it is in the dark phase, more artificial light from the night side will be visible from the Earth than the light projected from the day side. The total light emission from a planet with nocturnal lighting will be different from a planet with no artificial lights.
Observing the subtle changes will require the development of future generations of telescopes, but the technique can be tested close to home, using objects at the edge of the solar system.
Leib and Turner calculated that the best telescopes would be able to see light from cities the size of Tokyo at the distance of the Kuiper Belt - the region where Pluto, Eris and thousands of small icy bodies are found. So if there was any city there we can watch it now. Through observation, astronomers will be able to perfect the techniques and use them when the first Earth-sized planet orbiting another star in our galaxy is discovered.
"It is unlikely that we will find alien cities at the edge of our solar system, but the principle of science is to find a way to test," said Turner. "Before Galileo, the conventional wisdom was that heavier objects fall faster than lighter objects, but he tested the belief and found that they fall at the same rate."
As our civilization moves from radio and television transmissions to cable and fiber optics, we have become less detectable to aliens on radio frequencies. If the same is true for other intelligent civilizations, then artificial lights would be the best way to observe them from a distance.
Leib and Turner's work was published in the journal Astrobiology.
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Eitan, even if we receive broadcasts from a dead culture, it will be a great achievement like no other. Just the confirmation that we are not alone, is the greatest scientific discovery. As soon as we receive such confirmation, the search for others will increase, and the budgets will also arrive to finance all the crazy technologies that the search requires.
I agree with the others who say that other cultures wouldn't necessarily use lights the way we do. It is possible that their main sense will be smell, as it is in dogs, or that they are generally nocturnal creatures like bats, and then it is less likely that they will use lights. But since currently the only culture we know of does use night lights, and evolutionists claim that the eye evolved 8 separate times in the XNUMXnd century AD, this points to the possibility that eyes are a common evolutionary tool in the universe, and therefore night lights are also possible.
In any case, it will be a search for a very specific way of life, at a very specific time in its development, so not finding such lights does not indicate a lack of other cultures, but finding such lights definitely indicates.
The real question is whether it is really possible to distinguish such lights at a distance of 600 light years for example, from the background lights from the star?
If the answer to this is positive, then we need to invest in the development of technology, since we do not have many methods of detection for external cultures.
After trying to pick up alien transmitters, I was sure the next step would be a little more serious.
Even so, the chances with the conventional method tend to be zero, even if we start from the assumption that the aliens really ever transmitted something with technology similar to ours, the ray that if we do manage to receive such a transmitter is no longer relevant, and who knows if the same civilization that transmitted it actually exists, all this bullshit they Want to upgrade to another less effective bullshit, good luck to them...
Sabdarmish Yehuda
White dwarfs will never orbit a planet, no matter how massive it is.
Why not?
Because white dwarfs reach masses of more than half the mass of the Sun.
Just to remind you, our sun makes up 99.9% of the total mass of the solar system (including the Kuiper belt and Oort cloud, although I believe that thanks to Ticha, it's down to something like 99.8%).
And since the creatures in the book are humanoid, I don't think they lived on a super massive gas planet (massive enough to start nuclear fusion and function as a sun)
It is possible that much more than 500 years of light. There was light pollution in big cities also throughout the last thousands of years - even in London in the 19th century there were light poles with oil and gas for example. Cities of millions of people have existed for hundreds of years and even if you are right that in the future we will reduce light pollution.
Assaf - According to my understanding of the article, there is not necessarily a contradiction as far as I understand. I'm not sure about waiting two years to detect the transit of a planet in front of the star relative to us, but it is possible to follow the transit of the planet in front of the star in the same way when there is night and when there is day and compare the spectrum coming out of a star versus that of artificial light from the planet.
Interestingly, not a single commenter came up with the main flaw in this idea.
Just as our signal transmissions are disappearing with technological change, neither are city lights
Stay for a long time.
When in a short time the population of the world will increase so that the surface will not be enough, cities will be developed in the thick of the earth or under the sea level. This saving in space will also minimize the light signature of the cities into space.
That is, not only are we looking for creatures that need night lighting, we are also looking for them at such a specific stage in their development (perhaps less than 500 years).
Max
I am actually able to see in my wild fictional mind, a huge planet called "Shilgia" around which revolve seven bright white dwarfs. And once in a thousand years they all line up in one column and cast darkness on the other side of Shilgia!!
Sweet dreams Snow White
(:))
Sabdarmish Yehuda
Sabdarmish Yehuda
So that's it, it's a story from DVB.
In reality, there cannot exist a situation where there are seven stars in perfect balance.
In addition, a planet that would be gravitationally locked to its parent star would be too hot for habitation, not to mention that it would not have a magnetic field (created because the Earth works like a giant dynamo), so it would eventually have no atmosphere either.
But if it does manage to overcome the lack of atmosphere, did I already mention that there will be no tectonic activity of any kind? He will be a huge block of stone, and why is that bad? Because that means the planet's inhabitants won't be able to hide deep beneath the planet's soil to keep warm (you know, like they did in the Matrix)
There are, however, creative solutions
For example - a planet that will be at the point of gravitational equilibrium between two suns will always be illuminated and without nights
second option
That the planet will be gravitationally locked to its sun and then one side will always be lit and the other side will be completely dark.
I remember that I once read a fictional story about a planet that is in a system of 7 suns and once every thousand years darkness falls on it and the mess it causes to the frightened inhabitants.
But we only have one sun and it is currently peeking out from among the clouds!
What a beautiful evening!!
Have a good week everyone
Sabdarmish Yehuda
Luke, would you mind briefly explaining how in a binary system there are no nights on the planets?
It is more likely that planets will develop around the larger star in the system, and since stars in binary systems orbit each other at distances that exceed hundreds of astronomical units (binary systems with stars that actually dance on each other are quite rare as far as I remember), then because of the planet orbiting one of the stars, the other star will appear less bright than even the moon.
And of course, its position in the sky changes all the time, so there can be times when there are 2 suns in the sky, or 2 moons (or 3, or more, depending on how many moons orbit the given planet), so please, don't say things that have no basis.
A planet in a binary system would have the same day-night cycle as a planet orbiting a single star, because the twin star would be too far away to provide strong enough light.
Besides, if the two stars orbit themselves in orbits smaller than a few astronomical units (let's say the distance of Jupiter from the Sun), then there's no point even looking for civilization there, because the gravitational fluctuations of the struggling pair of stars will blow an astronomical object to hell (systems with three or more objects) They will always throw away the smaller objects to reach balance. Balance in astronomical parlance is 2 stars or less. So in such binary systems there will be no planets)
Not a serious article.
There is no way to see the surface of planets outside the solar system today and there probably won't be in the near future. The best method we have today is to point a powerful telescope towards a distant sun and wait a year or two in the hope that during this time a planet will pass between the sun and us and partially hide the sun so that the decrease in illumination intensity can be measured. The technology required to directly observe the surface of a star is currently impractical and borders on science fiction.
Luke took the words out of my mouth
If the creatures can see at night without lights?
It is possible to raise several more satellites like Kepler in different directions in the galaxy that checks the intensity of the light that falls during the eclipse of the star and then focus on these planets.
Luke, how do you propose to look for "basic chemical parameters" in stars that are light years away?
Yehuda, the idea is to test the technology on the edge of the solar system, not look for life there.
For the other opponents, there is something very reasonable in their proposal. If we tend to hide our communications (targeted transmissions to satellites, optical cable traffic, etc.) why wouldn't other cultures do the same? Light pollution is relatively difficult to hide. In today's searches for radio radiation, we are actually looking for a time window of several decades or hundreds of years in which a culture will transmit into space. It is also possible to get rid of the light pollution, if this is the case it might be worth predicting in advance what the next solution is...
The article must be proofread!
Sounds fascinating. Today, a powerful telescope of orders of magnitude sounds impossible. Tomorrow the impossible will be possible.
The approach in which we look for those who are similar to us in terms of technological development is an approach that will fail statistically.
It is a shame to invest resources in the search for the night lights of civilization because the chance of finding such lights is very low.
There can be planets with 2 suns (no night) or the inhabitants have infrared vision (no need for lighting) or they live underground, etc.
We need to look for basic chemical parameters to detect life and civilization.
Alien capitalism demands artificial justice!
First of all, the telescopes are getting more and more sophisticated and the technology makes it possible to build bigger and bigger telescopes. If they are built it will be for the purpose of deepening the knowledge about the evolution of the universe, and the search for planets will be a kind of bonus.
My dear father
Congratulations on your entry into the field of fiction.
The Kuiper belt is a few dozen astronomical units away, about a thousand light years. The nearest star is four thousand times the Kuiper belt and you should check the planets in the region of a thousand light years to have a chance of finding something, that is a million times. Would it seem to you that our civilization would spend a thousand or a million times more for telescopes than the best ones that exist today?
It's hard for me to believe
good week
Sabdarmish Yehuda
Definitely one of the funniest things I've heard.
Good luck!