NASA discovered a star that is older than our solar system. This information is important, as the age of the star can determine whether or not there are chances for life. Young stars usually release high levels of radiation that is not suitable for developing life forms.
Also, older stars enable planets to have more stable orbits and guarantee that it was possible for planets to develop steady surface that is resistant to stellar radiations. TRAPPIST-1, a solar system that is 40 light years away, is based around an old star that is twice as old as our Sun.
TRAPPIST-1 is between 5.4 and 9.8 billion years old, compared to our solar system that is 4.5 billion years old.
Three planets are existing in the habitable zone of TRAPPIST-1. They have a great potential for having liquid water. All seven planets have nightside and dayside, but existence of water could make three of them habitable for humans.
Adam Burgasser, astronomer from University of California in San Diego, explained how the fact that this is an old system guarantees that all planets evolved together which makes them very stable environment. In other case, the system would fall apart.
TRAPPIST-1 is a cool star, compared to other stars, but it is still uncertain whether or not it is habitable with life forms that are known to us. Also, the fact that there are conditions for liquid water doesn’t mean that there is really some. For example, Mars definitely had liquid water in the past, but doesn’t have it now. Reason for this is high level of radiation emitted by the Sun.
Also, even if there is a liquid water, that is not enough for a planet to be habitable by humans. For example, the atmosphere might be quite unfriendly towards life forms as we know it and could develop a ‘runaway greenhouse’ effect, that is present on Venus. To put it simply – it means that the surface can get overheated and no life forms can exist there.
There is still a lot of research to be done on TRAPPIST-1 before any final conclusions can be made. Nonetheless, even if there are no life conditions, NASA can gather valuable information on planet and atmosphere development.