There are no human-like space beings on this planet. And there is no trace of intelligent life either. But the chance that there is life on the red planet is present.
In 2015, NASA researchers found traces of liquid water on Mars. It's probably just a tiny bit, and the water is completely saturated with salt. But under the right circumstances, microbes could live in the water.
The bottom of this moon, which revolves around Saturn, is covered by a kilometer-thick layer of ice. Deeper below the surface, between the ice and the core, is an enormous ocean of liquid water.
Geysers inject water into space at the south pole of the moon. The Cassini spacecraft has flown through this water mist and has found organic molecules - molecules that are a condition for life in the underground sea.
Although smaller than our moon, this ice-cold celestial body contains about twice as much water as there is on earth. Just like on Enceladus, the water is hidden in an enormous underground ocean.
Last year NASA discovered geysers on this moon, which revolves around Jupiter. This may indicate that the sea is warm and has circumstances that make life possible. NASA wants to undertake a landing mission to Europe around 2022.
This greenish planet contains no traces of water, but is covered with liquid methane. It is the only other celestial body in the solar system with a liquid element on the surface.
Scientists do not consider it unlikely that a life form can adapt to these circumstances and can live in the methane sea. Titan is a moon of Saturn and almost as big as Mars. This makes it the second largest moon in the solar system - only the Jupiter moon Ganymese is even larger.
In this case it is not about one planet or moon that can contain life, but three. TRAPPIST-1 is a star that is hardly larger than Jupiter and much colder than our sun.
However, seven planets are close to the star, and three of them are in the habitable zone, where the temperature allows liquid water to surface. The planetary system is 39 light-years away from the Earth, and researchers hope that the planned space telescope James Webb can teach us more about the atmosphere of the planets.
In 2016, astronomers discovered an earth-like planet around Proxima Centauri, the star closest to the sun. The planet is in the area where liquid water on the surface is possible.
The astronomers hope to be able to bridge the 4.2 light years to the planet with space probes in the foreseeable future so that we can find out if there is life - and whether the planet is suitable for a future human colony.
There is an index for the degree to which planets are habitable. According to that index, Kepler-442b is more habitable than the earth.
Kepler-442b revolves around a star that is slightly smaller than the sun. This type of star has a lot of radiation activity in his youth, which would make life on Kepler-442b impossible. However, it is not known how old the star is. When he is old enough, the planet can contain life.
Gliese 667 Cc
At 24 light-years away, an earth-like planet was discovered in a triple system - a system with three stars.
Gliese 667 Cc revolves around the smaller of the three stars, but is located in the inner part of the habitable zone. The surface temperature is therefore probably somewhat higher than on earth.
This is the first earthy planet that was discovered in orbit around a star of the same type and size as the sun. It is 1400 light-years away from us and is therefore difficult to analyze.
The star around which the planet revolves is 1.4 billion years older than the sun and therefore gives more energy to the planet. If the greenhouse effect has not yet gone crazy on Kepler-452b, we must hurry if we want to find life there. Astronomers believe that the planet will be uninhabitable in a maximum of 500 million years due to the greenhouse effect.
We don't know much about this planet at a distance of 500 light years. And in the near future we will not be much wiser, because the next generation of space telescopes is not yet powerful enough to see it.
What we do know is that Kepler-186f is slightly larger than the earth. Simulations show that it is probably above zero degrees with a pressure of half an atmosphere. So good circumstances for life.