There is strong and growing evidence that Archaea are the closest current example of the original form of life on Earth and it is thus possible that the origins of life on other planets may be found in similar organisms.
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The term archaebacteria is now considered outdated since in recent years it has come to be understood that Archaea and Bacteria share little and have long and distinct evolutionary backgrounds.
The Archaea are single-celled microorganisms with no cell nucleus or any other membrane-bound organelles. As such, the are highly simplified. The archaeal lineage may be the most ancient that exists on Earth.
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They live in conditions similar to those likely to be found on other planets.
planatarium:)
There are eight planets, which can also be loosely descibed as major planets. Below that there are dwarf planets and then minor planets, also know as asteroids.
Scientists predict that they are planets because there wouldn't be random gas' from unknown places
The Telescope
Archaebacteria are the oldest and most primitive forms of life on planet Earth. It is postulated that primitive life on other planets would be most likely to resemble Archaebacteria. In addition, Archaebacteria were the first life forms to exist on Earth, so studying them allows xenobiologists to postulate how life may come into being on other planets.
They live in conditions similar to those likely to be found on other planets.
Studying the earth helps scientists to understand other planets since the earth is part of the solar system. Scientists use the features of the earth to compare them with what other planets hold.
mars because the scientists are searching right now
All life as we currently know it cannot exist without water (H2O). Scientists look for signs of water when searching for life on other planets.
scientists are studying about life on mars, but unfortunately it is still unknown! there is still no life on other planets.
C. Since Earth is the only planet that we know of with life on it, it is obviously the one that we study when it comes to the subject.
Archaebacteria
So far yes, but scientists are still searching for other life forms on planets such as Mars.
so they can find out about the early solar system and how planets were formed
They are gas planets
planatarium:)