The planets, like Earth and the living beings that inhabit it can be a infrequency. In the Milky Way, our galaxy, three out of four stars are red dwarfs like Trappist-1. So far, three solar systems with seven planets and a total of 10 habitable worlds have been discovered. The new finds breaks all records as it houses the largest number of terrestrial worlds and also contains three habitable, explains Ribas.
It is not that these systems are rare, it is that humans have not had the technology to find them until very recently. "It is estimated that these low-mass stars harbor two rocky planets on average, making these worlds the most Abundant, "explains Ribas. According to Caballero, "if there are 100,000 million stars in the Milky Way, there may be 80,000 million solar systems" as presented yesterday. And if there is life in them, this type of biology would be the most common in the galaxy.
For Ribas, the fundamental question is whether the planets have conserved some of the water they contained in their formation. Trappist-1 was formed more than 500 million years ago and, in the past, emitted much more heat and radiation. The three planets of the solar system that today are in the so-called "habitable zone" would have reached boiling temperatures millions of years ago. Only if part of that water was saved from evaporation can there be life in them, says Ribas.
In any case, the potential inhabitants of these planets would be very different from those of the Earth. The light of Trappist-1 is infrared, so if life has evolved, there will be eyes that can see infrared, red leaves for photosynthesis and other adaptations. "The photons of the star have very low energy, so the metabolism of these possible living beings would have to be much slower than ours," but their existence is within the possible, Caballero says. On Earth, for example, there are bacteriochlorophylls that use light at a wavelength similar to that emitted by Trappist-1.
NASA is already analyzing four of the planets, including the three habitable ones, with the infrared space telescope Swift, which will try to capture if any of them have traces of hydrogen, the dominant element in the envelope of gaseous giants like Neptune. For its part, the James Webb space telescope, which launches next year, will be able to search for water, methane, ozone and oxygen, gases that would indicate the presence of an Earth-like atmosphere. To confirm the observations we will have to wait until the next generation of the world's largest telescopes is completed in the next decade.
Much more difficult will be traveling
to this solar system. Propulsion technologies using current
space probes are too slow. For example, the few probes that have reached the
boundaries of our solar system would take "about 30,000 years to reach the
nearest star ," which is 4.5 light-years away, Caballero explains.
Trappist-1 is 40 light years away, which would take about 300,000 years