A team of astronomers made an important discovery with the Hubble Space Telescope, detecting helium in the atmosphere of exoplanet WASP-107b. This marks the first time researchers have found signs of the element in a planet beyond our solar system, and could also mean that scientists can study the composition of the air in exoplanets without having to wait for another space telescope to be launched for such a purpose.
According to a news release published by the European Space Agency, the multinational team made the discovery with Hubble’s Wide Field Camera 3, using the instrument to detect helium in WASP-107b’s atmosphere. The researchers consider this finding important, as helium ranks behind hydrogen as the universe’s second-most common element, and had never been confirmed to exist on exoplanets.
WASP-107b is located about 200 light-years away from Earth in the constellation Virgo, and is described as a “super-Neptune” exoplanet, one that has a similar diameter to Jupiter, but only one-eighth of the planet’s mass. Space.com observed that this makes it one of the lowest-density planets known to astronomers. The exoplanet also takes only 5.7 days to orbit its host star, and its atmosphere is definitely not conducive to life as we know it, with temperatures of 932 degrees Fahrenheit, or 500 degrees Celsius.
In an email to Space.com, University of Exeter researcher and study lead author Jessica Spake explained that her team used new methodologies to study the radiation-heavy upper reaches of an exoplanet’s atmosphere. The team’s findings were published Wednesday in the journal Nature.
“Hopefully, we’ll be able to study many more upper planetary atmospheres this way,” Spake added.
Both Space.com and the ESA press release explained the methodologies Spake and her colleagues utilized, which included studying the infrared spectrum of WASP-107b’s atmosphere. Prior to the new study, analyses of exoplanet atmospheres involved ultraviolet light, which is mostly blocked out by Earth’s atmosphere. That’s not the case with infrared radiation, which can be detected by ground-based telescopes, as it passes through Earth’s atmosphere, including its air and clouds. Furthermore, Spake noted that ultraviolet analysis only works with nearby exoplanets, but not more distant ones like WASP-107b.
“The strong signal from helium we measured demonstrates a new technique to study upper layers of exoplanet atmospheres in a wider range of planets.”
Hubble has been used to detect helium in the atmosphere for 1st time ever on a world outside of our solar system! Exoplanet WASP-107b is 1 of the lowest density planets known. While it is about the same size as Jupiter, it has only 12% of Jupiter’s mass: https://t.co/9ngmXQdfeW pic.twitter.com/S8BPXdMHUr— Hubble (@NASAHubble) May 2, 2018
Aside from the Hubble Space Telescope, astronomers might have another valuable resource available in the next few years for analyzing the atmosphere of exoplanets like WASP-107b. According to Spake, there’s a good chance that NASA’s James Webb Space Telescope, which is now expected to launch in May 2020, will be able to make these detections. Additionally, there are several ground-based telescopes, including Hawaii’s Keck Telescope and the European Southern Observatory’s Very Large Telescopes, that might be capable of consistent observations of exoplanet atmospheres.