Humanity has long hoped to find a planet in the sky similar to our own. The first planet outside our solar system was
discovered back in 2009. However, according to all the characteristics available to us, it is completely unsuitable for the emergence of life. There was a need for a
apparatus that could constantly observe the starry sky, analyzing all the changes. In addition, it was necessary to provide this apparatus with the opportunity
to constantly observe one area of the sky, which is impossible to do from the surface of the earth. All this led to the launch of the Kepler space telescope in 2009, to look for exoplanets.
Goals
The spacecraft launched by NASA was named Kepler. The planet this telescope was designed to search for can be at any distance from our system.
Therefore, the transit method is used to search for exoplanets. It consists in observing a small area of the sky and measuring the brightness of the stars. When a planet passes by a
star, the brightness decreases slightly. It is on this basis that one can find out whether the luminary has planetary-type bodies. To establish the period of
revolution and the number of planets, it is necessary to observe the star for at least three years. Only after that it can be argued that the brightness of the star decreases precisely because of
the reason for the passage of an exoplanet.
Besides, there may not be so few planets on which life can be formed or once already formed. That is why Kepler has been operating for so many years and there is no need to stop this project now.
Achievements
Today, more than 4 hundred exoplanets have been discovered using Kepler. All newly discovered ones are given the names of the telescope, with the assignment of a serial number and a letter. The letter shows how many planets the star has.
Of the hundreds discovered, a few may well be habitable, Kepler showed. Planet 186f, for example, was at one time seriously considered the "twin" of the Earth. However
at present we cannot be sure of the actual suitability of all discovered planets. Indeed, among other things, in order to be able to assert
that a celestial body is suitable for life, it is necessary to study a lot of really suitable ones. We have the opportunity to study only one planet, for sure
suitable for life - the Earth. There is very little of this material. But based on known facts, scientists believe that for the emergence of any life
the presence of water in liquid form is necessary. Thisthe parameter made it possible to introduce such a concept as the "habitable zone" - there are planets on which, due to
favorable distance from the star, there can be liquid water. In this zone, water has a chance not to evaporate or freeze. The presence of liquid depends on the brightness
of the star, and on the remoteness of the planet itself from the star.
Second Earth
What needs to be further clarified in order to claim that an Earth-like planet has been discovered? "Kepler", be that as it may, can not give us such information
. It was created only to detect the very presence of an exoplanet. However, we know for sure that the characteristics of the planet can be completely different.
For example, even a discovered gas giant cannot be a guarantee that there is no water on it. After all, he may well have a satellite with a suitable atmosphere.
Many factors are responsible for the probability of the emergence of life known to us: the presence of satellites, the distance from the star, the activity of the star, the presence of an unstable
star in the neighborhood, giant planets in the star system. Based on the data known to us, scientists suggest that life can arise, first of all, on those planets that are as similar as possible to our own - revolving around a sun-like star in a similar orbit, having a similar mass, age, radius and other parameters. Such a multitude of demands for a "second Earth" leads to the fact that the discovery of planets that are similar to the Earth, causes violent emotions
scientists and laymen. Currently found twoexoplanets that require closer attention, as they may well be the ones for which the Kepler astronomical satellite was created. Planet 186F and 452b.
Kepler 186f
186f Kepler - planet discovered in April 2014. Despite the considerable remoteness, we managed to find out quite a lot about it: it revolves around a red dwarf with a frequency of 130 Earth days, 10% larger than the Earth. It orbits around the outer edge of the habitable zone. The statement of astrophysicists was greeted with enthusiasm, immediately a lot of ordinary people and even quite respected publications began to suggest the appearance of the planet, its characteristics and the bonuses that the Earth could receive from such a "sister". However, over time, scientists managed to bring dreamers back to reality.
In order to say exactly how likely life is on the planet, you need to have much more data. For example, you need to find out the presence of an
atmosphere, its composition, the composition and nature of the planet itself, surface temperature and many other characteristics. At present, we do not have the equipment
capable of finding out all the factors of interest to us at such a huge distance. However, in the 2020s, it is planned to launch a similar mechanism into orbit, for a detailed study of exoplanets.
How long does it take to fly to the planet Kepler 186f? Well, it is practically next to us - it is only some 400 light years away.
Kepler 452b
Located fromus a little further away - at a distance of 1400 light years. The star around which this likely "double" of the Earth revolves is similar to our Sun.
Kepler 452b's orbit is almost identical to Earth's. A day is equal to our 385 days. The size of the planet is significantly larger than the Earth - the radius is 60% larger. Thus, if the density of this planet is the same as that of the Earth, then it will weigh 4 times more, which will lead to greater gravity - 1.5 times. The age of the star system, in which the planet of interest "lives" in, is 6 billion years, against 4.5 - the age of our Sun.
Could there be life on this planet? Maybe. But maybe not. Until there is accurate and modern equipment that will allow us to study the planets
located at such vast distances, we will not be able to say exactly what this and others are, we will not be able to see photos of the planet Kepler 452b and others like her.
