A Neptune-size planet beyond the solar system is discovered to have clear skies and steamy water vapor.
Astronomers using data from three of NASA’s space telescopes — Hubble, Spitzer and Kepler found the smallest exoplanet HAT P-11b, known to have the wet stuff yet with a technique called transmission spectroscopy, in which a planet is observed as it crosses in front of its parent star.
Previously components of atmosphere of several massive Jupiter-size giants were examined.
The discovery that paved a new path in the hunt for planets sustaining life, was reported Wednesday in the journal Nature.
“It’s a fantastic observation,” said Knicole Colon, astronomer, Lehigh University, Bethlehem, Pennsylvania, and a National Geographic Young Explorer, who was not part of the research. “It opens up a whole new regime in our attempt to understand how exoplanets form and what they’re made of.”
It is residing at about 124 light-years away in the constellation Cygnus (The Swan). The alien planet is about five times as big as Earth and probability shows a thick gaseous atmosphere like Neptune. Its “year” last about five days, and its surface temperature is above 1,100°F (600°C).
It is supposedly having a rocky core and a mantle of fluid and ice.
“We set out to look at the atmosphere of HAT-P-11b without knowing if its weather would be cloudy or not,” said Nikku Madhusudhan, from the University of Cambridge, UK, from the study. “By using transmission spectroscopy, we could use Hubble to detect water vapour in the planet. This told us that the planet didn’t have thick clouds blocking the view and is a very hopeful sign that we can find and analyze more cloudless, smaller, planets in the future. It is groundbreaking!”
Drake Deming, a co-author of the study also from University of Maryland, USA said, “We are working our way down the line, from hot Jupiters to exo-Neptunes,”
“We want to expand our knowledge to a diverse range of exoplanets.”
Researchers examined the atmospheres of four other smaller exoplanets for the study, two roughly the size of Neptune and two smaller super-Earths but the results were disappointing.
The chemical compositions of the other four planets got blocked by a familiar phenomenon — clouds.
“We’ve just been seeing a whole lot of nothing,” said Eliza Kempton, Grinnell College, Iowa who was not involved in the research.