Cloudy days on exoplanets may hide atmospheric water

Astronomers have determined many hot Jupiters with water of their atmospheres, however others seem to have none. Scientists at NASA's Jet Propulsion Laboratory, Pasadena, California, desired to discover what the atmospheres of these giant worlds have in common.

Researchers focused on a set of hot Jupiters studied with the aid of NASA's Hubble area Telescope. They discovered that the atmospheres of approximately 1/2 of the planets were blocked by way of clouds or haze.

"the motivation of our study became to look what those planets could be like if they were grouped together, and to see whether they share any atmospheric homes," said Aishwarya Iyer, a JPL intern and grasp's degree candidate at California kingdom university, Northridge, who led the examine.

the new observe, published inside the June 1 problem of the Astrophysical magazine, indicates that clouds or haze layers could be preventing a vast amount of atmospheric water from being detected with the aid of space telescopes. The clouds themselves are probably no longer product of water, because the planets in this sample are too warm for water-based clouds.

"Clouds or haze appear to be on nearly each planet we studied," Iyer stated. "you have to be cautious to take clouds or haze into consideration, otherwise you can underestimate the quantity of water in an exoplanet's atmosphere by means of a aspect of ."

within the take a look at, scientists looked at a set of 19 warm Jupiters formerly located by means of Hubble. The telescope's huge subject camera 3 had detected water vapor inside the atmospheres of 10 of these planets, and no water on the opposite nine. however that data was spread across extra than a dozen research. The techniques of reading and interpretation numerous due to the fact the research have been performed one at a time. There had no longer been one overarching evaluation of all these planets.

To evaluate the planets and search for styles, the JPL group had to standardize the facts: Researchers blended the datasets for all 19 warm Jupiters to create an average usual mild spectrum for the organization of planets. They then in comparison these information to fashions of clear, cloud-loose atmospheres and people with various cloud thicknesses.

The scientists decided that, for almost every planet they studied, haze or clouds had been blocking 1/2 of the surroundings, on common.

"In some of these planets, you may see water peeking its head up above the clouds or haze, and there should nevertheless be greater water beneath," Iyer stated.

Scientists do not yet understand the character of these clouds or hazes, together with what they may be they made of.

"Clouds or haze being on almost all these planets is pretty unexpected," said Robert Zellem, a postdoctoral fellow at JPL and co-writer of the study.

the results of this end result trust findings published in the Dec. 14, 2015, problem of the magazine Nature. the character have a look at used records from NASA's Hubble and Spitzer space Telescopes to suggest that clouds or haze might be hiding undetected water in hot Jupiters. This new study makes use of exoplanet facts from a unmarried tool on Hubble to uniformly symbolize a bigger institution of hot Jupiters, and is the primary to quantify how an awful lot of the ecosystem could be shielded because of clouds or haze.

the new studies may want to have implications for observe-up research with future area observatories, inclusive of NASA's James Webb area Telescope. Exoplanets with thick cloud covers blocking the detection of water and different substances may be less suitable targets for greater sizable take a look at.

those outcomes are also essential for figuring out how planets shape, scientists say.

"Did these planets form in their present day positions or migrate toward their host stars from farther out? knowledge the abundances of molecules along with water enables us answer the ones questions," Zellem stated.

"This paper is an thrilling breakthrough for the observe of exoplanets and evaluating their homes," stated Mark Swain, look at co-writer and organization manager for the exoplanet discovery and technology group at JPL.

Michael Line of the college of California, Santa Cruz, additionally contributed to the examine. other co-authors from JPL protected Gael Roudier, Graca Rocha and John Livingston.