Hubble Space Telescope Discovers Two Cloudy Exoplanets

NASA scientists begin to decipher the atmospheric characteristics of two common planet-types.

hubble, space, exoplanet, exploration, science, atmosphere, life, Caltech, Chicago, Researchers working with NASA’s Hubble telescope have described the characteristics of two common exoplanet varieties within the Milky Way – an important first for planetary science.

According to two papers published in the January 2 issue of Nature, researchers were able to use the space telescope to survey both alien atmospheres by means of chemical spectral analysis.

In the first paper, Cal Tech planetary scientist Heather Knutson and her team surveyed GJ436b, a Neptune-sized body located 36 light years away in the Leo constellation. From her survey, Knutson identified a featureless spectra with no chemical signatures in its atmosphere.

“Either this planet has a high cloud layer obscuring the view, or it has a cloud-free atmosphere that is deficient in hydrogen, which would make it very unlike Neptune,” said Knutson. “Instead of hydrogen, it could have relatively large amounts of heavier molecules such as water vapor, carbon monoxide, and carbon dioxide, which would compress the atmosphere and make it hard for us to detect any chemical signatures.”

, Space, Chicago, Exploration, Science, exoplanet, life, caltech, atmosphere,HubbleIn the second paper, Laura Kreidberg and Jacob Bean of the University of Chicago leveraged Hubble’s power to get an up close look at GJ1214b, another Neptune-sized planet located 40 light years away in the Ophiuchus group.

While spectral analysis returned another chemically void map, researchers believe they have ample evidence of high altitude clouds cascading over the planet. What’s more, the precision of the telescope data made clear that the exoplanet was not a cloud-free slurry of water vapor and various other chemicals.

“Both planets are telling us something about the diversity of planet types that occur outside of our own solar system; in this case we are discovering we may not know them as well as we thought,” said Knutson. 

While a whole host of mysteries still remain about the composition and atmospherics of nearby exoplanets, these two papers are milestones in our understanding of worlds beyond our own solar system – and a sign of just how much we still have left to learn.

Image Courtesy of NASA