Awkward extraterrestrial atmospheres
Using the effective eye of the Hubble Space Telescope two Internationals team of scientists have found traces of water, little but unmistakable, in the atmosphere of five extrasolar planets. The two studies can be found in The Astrophysical Journal.
To analyze the composition of the atmosphere of an extrasolar planet, astronomers observe it as it transits in front of its host star, and look at what wavelengths of light pass through or are partially absorbed.
Credit: NASA’s Goddard Space Flight Center
Wide Field Camera 3 hits anchor. Then the mythical supereye of Space Telescope Hubble is able to fathom the farthest reaches of the galaxy, this time the dowser had fallen in the in the garb of the diviner.. And in a few months water has been identified in the misty atmosphere from five extrasolar planets. And it is precisely spectroscopic analysis of the backlight – the issue of the five -star view through the atmosphere planet – that are immersed in the form of lines of absorption, the unmistakable signs of the precious molecule.
The names of the five planets – all hot Jupiters , warm gas giants, that orbit at a distance not far from us – are WASP- 17b, HD209458b , WASP- 12b, WASP- 19b ‘ s XO -1b . And we must be aware that this is certainly not the first time that scientists observed the presence of water in the atmosphere of extrasolars.
“This study inaugurated the possibility of measurement of the presence of water in the atmosphere of various extrasolar planets, allowing for example to confront which one is the warmest or the coldest planet,” says Avi Mandell, of NASA’s Goddard Space Flight Center of Greenbelt, Maryland, the first author of the research results related to WASP- 12b, WASP- 19b, WASP- 17b that were published today in the Astrophysical Journal. Analyzing the atmosphere of an extrasolar planet is in an extraordinarily difficult job, but we still managed to pull out a very clear signal, and what it says is that there are signs of water, ” echoes Drake Deming of the University of Maryland, the leading chief researcher of the team and that is already busy with two other worlds Altria Two Worlds and HD209458b’s XO- 1b, and thanks to one of the new technics and a longer time of exposure, they managed to further improve the sensitivity of the measures.
The researchers were surprised, by both groups, but not by the presence of the water but as much as to the weakness of signs detected, least intense than expected. The hypothesis is that to attenuate the mist layer or the dust layer that surrounds each of the five planets. A little as the fake fog and colors in the photography, making them indistinct, so the mantle that covers these planets would appear to alter the profile of the signature of water and other molecules present in their atmospheres.