Telescope NASA discovered potentially habitable seven “sisters” of the Earth
Star TRAPPIST-1, distant from the Earth only 40 light-years she was the owner from the seven planets, and three of them are in the center of the “zone of life” and may have water and a thick atmosphere.
MOSCOW, 22 Feb — RIA Novosti. The recently discovered star TRAPPIST-1 in the constellation of Aquarius turned mistress from seven analogues of the Earth, and three of them are in the center of the “zone of life” and are assumed to possess water and a thick atmosphere, according to a paper published in the journal Nature.
“The opening of the TRAPPIST system-1 we knew only four real earth-like planets that we can study the Earth, Mars, Venus and mercury. Now their number has increased to seven, and we can study them not in five to ten years, and right now. It can be expected that the first news about their properties will appear in the coming weeks and months. The story of TRAPPIST-1 is just beginning,” — says the opening of Michelle Gillon (Michel Gillon), astronomer at the University of liège (Belgium).
Seven sisters
In may last year, astronomers from MIT announced the discovery of a very unusual star system — TRAPPIST-1, remote from Earth 40 light-years towards the constellation of Aquarius. Then it was reported that three planets orbiting this red dwarf star, are inside the so-called “zone of life”, where water can exist in liquid form, and their weight is presumably comparable to the earth.
Later, scientists studied a range of rays of the star TRAPPIST-1, passed through an air sheath planets on the way to the Ground, and found that a rocky planet similar to Earth, but also found hints of the presence of water, oxygen and carbon dioxide in their atmospheres. However, not all astronomers were convinced in the existence of these planets, noting that the periodic decrease in brightness of the star, which they had discovered, could be generated by the invisible light for us-companion TRAPPIST-1.
Gillon and his colleagues studied the properties of these planets, observing the star system using the TRAPPIST telescope in Chile, and space telescope “Spitzer”. As scholars have noted, they assumed that will be able to easily obtain information on the size, mass and atmospheric composition of the planets due to the short distance to the TRAPPIST-1, relaxed nature of the star and its small size that facilitates observation of the planets shadow on its surface.
These observations led to the unexpected discovery was that planets do not actually three, and seven, and six of them are within the “zone of life”.
With high-resolution telescopes and long-term observations of planetary scientists was the first to accurately measure the diameter and mass of six of the seven planets and get some data on the composition of their atmosphere.
The mystery of the fifth planet
All planets of the size of the Earth — their radius ranges from 0.7 to 1.08 radius of our planet, and the weight from 0.41 to 1.38. Accordingly, their density equal to the earth or below it that talks about their rocky nature or that they are the planets oceans.
Unlike our planet, the seven sisters turn in a very tight orbit around a TRAPPIST-1 – year for them lasts from one and a half days to about two weeks
Even the last planet of the system, TRAPPIST-1h is about four times closer to the star than mercury comes to the Sun.
Almost all the planets should rule the earth or Mesopotamia weather with average surface temperatures around zero or 20-30 degrees below zero. Only the first two planets knocked out of the trend of temperature on them exceed 70-100 degrees of Celsius, which probably makes them more like Venus than Earth.
If we talk about the probability of life, as most expect the three Central planets d, e and f
According to Emory Trio (Amaury Triaud) of the Astronomical Institute in Cambridge (UK), the greatest chance for the origin of life have planet f, the climate is fairly mild and cool in order that it could be a water and organic.
The exact answer to this question, you can get pretty soon — according to Trio, some features of the climate of the planet f and its neighbors will be known in the coming years, and the first reliable information on its habitability can be obtained in the “within this decade”.
Are we alone in the Universe?
On the possibility of life on these planets, as recognized Gillon may be affected by two unusual properties of the system TRAPPIST-1. According to him, all the planets with very high probability is captured by the tidal forces of the star, causing it always turned to one side. It may have a negative impact on the climate of planets and make them virtually uninhabited.
In addition, the planets themselves are in the so-called orbital resonance. As a rule, this phenomenon occurs as a result of gravitational interaction of heavenly bodies, which leads to stabilization of their orbits and the appearance of a strict mathematical relationship between the periods of their rotation. For example, Saturn and Jupiter are synchronized so that for two years, Saturn Jupiter makes five turns around the Sun.
Such processes, as explained by the Belgian planetary scientists, can warm the depths of the planets in the system are TRAPPIST-1 and cause massive outbreaks of volcanism, such as those that occur on IO, the companion of Jupiter. This factor will also influence the auspiciousness of planets to the origin of life, although it is difficult to say unequivocally in the positive or negative direction.
The discovery of a family of seven planets TRAPPIST-1, as described Gillon RIA Novosti, does not allow us to talk about how often in our Galaxy, meet mnogoletnie star system similar to our Solar system or similar to it
“Here we are dealing with a relatively rare type of star, one of the most cool objects in the milky Way. We do not expect that analogs of the Solar system can arise from such stars — they simply do not have enough materials to make them could be large planets similar to Jupiter or Saturn. Therefore, we have not yet found analogues of the Solar system are red dwarfs and they are unlikely to find,” explains the scientist.
If you talk about stars similar to the Sun, the data from the “Kepler” and other telescopes, says Gillon, show that such systems are extremely rare. It is estimated that only 10% of the planetary systems of these stars are similar in structure to the Solar system. Statistics for an accurate assessment of this share yet, but Belgian scientists believe that the Solar system is very rare and almost unique thing for the Galaxy. Systems, such as TRAPPIST-1, it should meet more often.
In any case, TRAPPIST-1 has initially a high chance for the origin of life, since these stars live tens and hundreds of times longer than the Sun and other relatively large bodies. As expressed Gilon, the Sun will go out long ago, when TRAPPIST-1 has not come out from childhood, which gives a great chance for the origin of life in the future or even in the past.