NASA's Hubble telescope discovers water vapor In small exoplanet's atmosphere

In a groundbreaking revelation, astronomers utilizing NASA's Hubble Space Telescope have detected water vapor on the relatively diminutive exoplanet GJ9827d, approximately twice the diameter of Earth. This discovery suggests the potential existence of a planet with a water-rich atmosphere, as reported by NASA.

Björn Benneke from the Trottier Institute for Research on Exoplanets at Université de Montréal expressed the significance of this finding, stating, "This would be the first time that we can directly show through an atmospheric detection that these planets with water-rich atmospheres can actually exist around other stars. This is an important step toward determining the prevalence and diversity of atmospheres on rocky planets."

Co-principal investigator Laura Kreidberg from the Max Planck Institute for Astronomy added, "Water on a planet this small is a landmark discovery. It pushes closer than ever to characterizing truly Earth-like worlds."

Despite the impressive findings, astronomers remain uncertain about the composition of the planet's atmosphere. The debate centers on whether the atmosphere is primarily composed of water, possibly a remnant from a primordial hydrogen/helium atmosphere, or if the Hubble Telescope merely measured a small amount of water vapor in a hydrogen-rich atmosphere.

According to NASA, the team is currently considering two possibilities. One scenario suggests that the planet retains a water-laced, hydrogen-rich atmosphere. Alternatively, it may resemble a warmer version of Europa, Jupiter's moon, which boasts a crust containing twice as much water as Earth.

With a scorching temperature of 800 degrees Fahrenheit, akin to Venus, the planet would be inhospitable and steamy if its atmosphere is predominantly composed of water vapor.

The discovery of GJ9827d dates back to 2017 when NASA's Kepler Space Telescope identified the exoplanet. Completing one orbit around a red dwarf star every 6.2 days, GJ9827d is situated in the Pisces constellation, approximately 97 light-years away from Earth.