Today Venus is one of the most inhospitable places in the solar system from a human point of view, but earlier there were most likely oceans here that could well have been inhabited, scientists say. However, experts say that the oceans were here for a short time and in the earliest stages of the planet's existence.
Astronomers came to similar conclusions based on information transmitted by the European orbiter Venus Express, which is now operating in orbit around Venus. Based on the information transmitted by this device, scientists have come to the conclusion that now the Earth and Venus are very different, but in the past, these planets were much closer.
Earth and Venus had a number of key similarities that made them equally suitable for the origin of life. The planets, in particular, had similar orbits, sizes, and masses. “The basic composition of the planets is very similar,” says Hakan Shvedem, an ESA scientist.
However, there is very little water on Venus today. If all the water vapor could be compressed under pressure and lowered to the planet's surface, then a "global puddle" about 2.5 cm deep would have turned out. For comparison: on Earth, this "global puddle" would have been about 3 km deep.
Nevertheless, there was water on Venus and there was a lot of it, astronomers are sure. True, it was billions of years ago. Over time, Venus lost all the water stored here into outer space through evaporation. Harsh ultraviolet radiation from the sun literally threw water molecules out of the planet.
Venus Express has now measured the amount of water vapor leaving the surface of Venus into space. Now on Venus, hydrogen evaporates twice as much as oxygen. Recall that water is made up of one oxygen and two hydrogen.
“Even now, the size of the vapor is quite large. All indications are that Venus had a lot of water in the past,”says Colin Wilson of the University of Oxford. According to him, not necessarily there were oceans on Venus, not some kind of water bodies here is very likely. In addition, scientists say that the planet's atmosphere was saturated with water vapor, and given the fact that it was well warmed up by the Sun, all conditions for life could exist here.
cybersecurity.ru
Promotional video:
An analysis of the composition of the meteorites that formed in the bowels of Mars allowed scientists to find out that they contain the same number of water molecules as the earth's mantle.
The discovery not only changes the understanding of the geological history of the Red Planet, but also allows us to take a fresh look at how water got to the Martian surface - after all, in the distant past, oceans existed on it.
A group of scientists led by Francis McCabbin from the University of New Mexico (USA) investigated the so-called shergottites - rare meteorites, which are melts crystallized on the surface of Mars from its mantle (a layer under the planet's crust). These rock samples left Mars as a result of a collision with other celestial bodies about 2.5 million years ago, after which they were brought to our planet. Spectrometric studies of such meteorites help scientists understand the geological processes that once took place on Mars.
Source of the Martian oceans
“We analyzed two meteorites, each with a different history,” explained co-author of the Geology article, Eric Hoiry, of the Carnegie Institution in Washington. - The matter of one of them was thoroughly 'mixed' with other elements during formation, while the other retained its original chemistry. However, the difference in water concentration was minimal, despite the completely different composition of the samples."
According to him, such a result suggests that water entered the composition of Mars during its formation and that the water reserves are hidden in its internal structure. The Martian meteorites were found to contain between 70 and 300 milligrams of water per kilogram of rock. According to the scientist, this value is comparable to the water content in the Earth's mantle, which is 50-300 milligrams per kilogram of matter.
“There is a lot of evidence that liquid water has existed on the surface of Mars for at least some time. Therefore, a paradox arose - why the mantle was “dry” according to previous estimates. Our findings have solved this mystery and allow us to assume that water on the surface of Mars could have appeared mainly due to volcanic activity, "Hoyri said, quoted by RIA Novosti. "Our research not only explains where the water on Mars comes from, but also reveals the storage mechanism of hydrogen in all terrestrial planets during their formation," concludes Maccabin.
rg.ru
