NASA Discovers Strange, 'Heavy Metal' Planet

Do you love listening to Slayer, Metallica, Megadeth or Slipknot? You may be a solid heavy metal fan. 

But this article explores a different kind of “heavy metal.” NASA recently discovered an exoplanet in a planetary system 900 light-years from Earth.

Astronomers are calling WASP-121b a real heavy metal planet because of its unique composition and activities. It has been leaking magnesium and iron gas, the first ever Jupiter-sized planet allowing such elements to escape its atmosphere, NASA said in a press release

WASP-121b basically is a hot version of Jupiter. Its extremely high temperatures occur because of its “dangerously close” distance to its star.

Such small gap exposes the planet to strong gravitational tidal forces from the star, which made WASP-121b football shaped.

The exoplanet’s upper atmosphere alone maintains a 4,600 Fahrenheit temperature. That is nearly 10 times hotter than any known planetary atmosphere.

"Heavy metals have been seen in other hot Jupiters before, but only in the lower atmosphere," David Sing, lead researcher from Johns Hopkins University, said. "With WASP-121b, we see magnesium and iron gas so far away from the planet that they're not gravitationally bound."

Sing’s team reported the discovery in the Astronomical Journal. NASA found WASP-121b through the Hubble Space Telescope. 

The space agency detected the ultraviolet light from the system’s host star that appears brighter than the Sun. Aside from the planet’s close distance to its star, another factor that makes it a sizzling planet are the escaping heavy metals. 

"These metals will make the atmosphere more opaque in the ultraviolet, which could be contributing to the heating of the upper atmosphere," Sing said. 

Because of WASP-121b’s extreme environment, NASA is considering it to be part of the first targets of its new James Webb Space Telescope. Future studies would focus on the planet’s water and carbon dioxide to give astronomers more complete inventory of the chemical elements coming from its atmosphere.

NASA said the discovery of the heavy metal planet offers new information on how planets could lose primordial atmospheres. WASP-121b is part of the agency’s Panchromatic Comparative Exoplanet Treasury survey, which observes 20 exoplanets, including super Earths and other worlds as massive as Jupiter.

WASP-121b This artist's illustration shows an alien world that is losing magnesium and iron gas from its atmosphere. NASA, ESA, and J. Olmsted (STScI)