How can we tell if far-away distant objects in space are of/from alien life or not?

[tm20]

The first known interstellar object to visit our solar system was an object which they named ʻOumuamua, discovered on October 19, 2017. It was classified as an asteroid until new data showed that it behaved more like a comet. It was said that it is impossible to know what makes up ʻOumuamua, so how could we tell if objects like these in space are of/from alien life or not?

Sources:
https://www.nasa.gov/feature/jpl/chasing-oumuamua
https://solarsystem.nasa.gov/asteroids- ... /in-depth/

[Chris Peterson]

The first known interstellar object to visit our solar system was an object which they named ʻOumuamua, discovered on October 19, 2017. It was classified as an asteroid until new data showed that it behaved more like a comet. It was said that it is impossible to know what makes up ʻOumuamua, so how could we tell if objects like these in space are of/from alien life or not?

Sources:
https://www.nasa.gov/feature/jpl/chasing-oumuamua
https://solarsystem.nasa.gov/asteroids- ... /in-depth/

Well, at the least, there is no reason to make such an assumption without some sort of reason to do so. Simply coming from outside the Solar System isn't sufficient.

The more observations we can make, the more we are likely to learn. That means detecting such objects earlier. That is certain to happen over the next years as we operate more and faster survey telescopes.

[Fred the Cat]

You might expect ET to phone home but what type of signal could be used and where would it be aimed?

[Arcturus]

Have you ever noticed that all search for intelligence are always aimed far away from us?
I just wonder why.

[neufer]

Have you ever noticed that all search for intelligence are always aimed far away from us?

I just wonder why.

It's both actually : https://www.gocomics.com/frank-and-ernest/2019/12/19

[Ann]

Have you ever noticed that all search for intelligence are always aimed far away from us?
I just wonder why.

Everything in space is far away from us, apart from the Earth's own Moon. Even the rest of the Solar system is far away from us.

As for the Solar system, we can be almost perfectly sure that if there is life on another planet or moon, it must be hiding below ground or below a very thick ice sheet. If there was intelligent life on another planet or moon in the Solar system, and if that life was broadcasting "intelligent signals" into space, I personally feel convinced that we would have detected their signals by now. So if you ask me, there are no other intelligent species deliberately or accidentally "leaking signals into space" in our own Solar system.

What about nearby solar systems? Unfortunately, they are all very faraway. Even Alpha Centauri, the nearest star after the Sun, is really very far away!

We know that the small red star Proxima Centauri, which is a likely member of the Alpha Centauri system, has a planet.

Wikipedia wrote about the planet of Proxima Centauri:

Proxima Centauri b orbits the star at a distance of roughly 0.05 AU (7,500,000 km; 4,600,000 mi) with an orbital period of approximately 11.2 Earth days, and has an estimated mass of at least 1.3 times that of the Earth. Its habitability has not been established, though it is unlikely to be habitable since the planet is subject to stellar wind pressures of more than 2,000 times those experienced by Earth from the solar wind.

It's not that we are not looking for advanced life and interstellar signals. Have you heard of SETI@home?

Wikipedia wrote:
SETI@home ("SETI at home") is an Internet-based public volunteer computing project employing the BOINC software platform created by the Berkeley SETI Research Center and is hosted by the Space Sciences Laboratory, at the University of California, Berkeley. Its purpose is to analyze radio signals, searching for signs of extraterrestrial intelligence, and as such is one of many activities undertaken as part of the worldwide SETI effort.
...
The first of these goals has to date yielded no conclusive results: no evidence for ETI signals has been shown via SETI@home. However, the ongoing continuation is predicated on the assumption that the observational analysis is not "ill-posed.” The remainder of this article deals specifically with the original SETI@home observations/analysis. The vast majority of the sky (over 98%) has yet to be surveyed, and each point in the sky must be surveyed many times to exclude even a subset of possibilities.

So we are looking. It is just that even our own galaxy is so big that no human being can even begin to picture its true scale. And there are billions and billions and billions of stars in it, but they are all very far away, and their planets are so small and dark, and the signals of any intelligent extraterrestrials are likely to spread out and become virtually undetectable over the vast, vast, vast distances we are talking about.

So we are looking. But bear in mind that so far we haven't even found a single planet that is really, truly, undoubtedly habitable.

Star Trek and Star Wars are a lot of fun, but the reality of space couldn't be more different from the candy pop sci-fi movies.

Ann

[Fred the Cat]

Are we alone in the Milky Way? Scientific American asks that type question in this month’s issue. I’d like to believe our Earth-Moon-Sun system had a part in the persistence of life on Earth possibly explained by gravity’s organizing effect on the types molecules uniquely present on our planet to create the “helixitricity” of all the varieties DNA.

That way I’d be reassured that when species disappear, what takes their place is not the will of God but the will of physics. Long live the Fluberplasts of the future and all life that may flourish on worlds unknown!

[neufer]

Have you ever noticed that all search for intelligence are always aimed far away from us?
I just wonder why.

Everything in space is far away from us, apart from the Earth's own Moon. Even the rest of the Solar system is far away from us.

As for the Solar system, we can be almost perfectly sure that if there is life on another planet or moon, it must be hiding below ground or below a very thick ice sheet. If there was intelligent life on another planet or moon in the Solar system, and if that life was broadcasting "intelligent signals" into space, I personally feel convinced that we would have detected their signals by now. So if you ask me, there are no other intelligent species deliberately or accidentally "leaking signals into space" in our own Solar system.

The only way to make certain is to radio broadcast a message like... say:

• 'Person, woman, man, camera, TV':

and to see if we get the appropriate response:

• 'Person, woman, man, camera, TV':

(We'll give them extra points if they get the order correct.)

[Chris Peterson]

Have you ever noticed that all search for intelligence are always aimed far away from us?
I just wonder why.

Everything in space is far away from us, apart from the Earth's own Moon. Even the rest of the Solar system is far away from us.

As for the Solar system, we can be almost perfectly sure that if there is life on another planet or moon, it must be hiding below ground or below a very thick ice sheet. If there was intelligent life on another planet or moon in the Solar system, and if that life was broadcasting "intelligent signals" into space, I personally feel convinced that we would have detected their signals by now. So if you ask me, there are no other intelligent species deliberately or accidentally "leaking signals into space" in our own Solar system.



Ann

You are so right that there is nothing else to be said. How can we explore planets that are so far away from us that even a few humans' lives will not be enough to get to them and check if there is something hiding below ground or below a very thick ice sheet?

Our entire solar system is highly accessible to our investigation of life beyond Earth. Nothing beyond our solar system is similarly accessible, except in limited ways. We are close to being able to detect life on planets around distant stars, although we will not be able to do much more than make a strong case that it exists, without any details. The detection of intelligent life will require the good fortune of receiving some kind of signal.

[neufer]

Click to play embedded YouTube video.

How can we explore planets that are so far away from us that even a few humans' lives will not be enough to get to them and check if there is something hiding below ground or below a very thick ice sheet?

Our entire solar system is highly accessible to our investigation of life beyond Earth. Nothing beyond our solar system is similarly accessible, except in limited ways. We are close to being able to detect life on planets around distant stars, although we will not be able to do much more than make a strong case that it exists, without any details. The detection of intelligent life will require the good fortune of receiving some kind of signal.