Night Sky Gaze

Hubble Telescope Reveals Football-Shaped Exoplanet That Emits Heavy Metals

  • NASA has recently discovered heavy metals escaping the atmosphere of a football-shaped exoplanet. The planet’s extreme heat is the reason for its emission of metals.
  • An exoplanet is a planet that exists outside of our solar system in which all of the planets orbit the Sun.
  • WASP-121b is an exoplanet and a hot Jupiter—resembling Jupiter with a short orbital period of no more than ten days—that gets so hot, it cannot contain metals such as magnesium and gas iron.
  • Lead researcher at Johns Hopkins, David Sing believes this discovery has great importance in that it demonstrates another way in which a planet can lose its atmosphere.

NASA’s Hubble Space Telescope has recently discovered magnesium and iron gas escaping the exoplanet named WASP-121b. Rather than compressing into the clouds, the “heavy metals” are leaving the exoplanet sitting outside the solar system. This new discovery shows astronomers another way that a planet can lose its atmosphere.

What is An Exoplanet?

Within our solar system, each of the planets orbits the Sun. Their atmospheres and conditions are in direct relation to its distance and orbital rotation to the Sun. But an exoplanet is one that exists outside (“ex-“) our solar system.

Exoplanets orbit their own super-bright stars which is what makes detecting them so difficult. The WASP-121b orbits the star known as WASP-121 and is approximately 900 lightyears from the Earth. The exoplanet orbits its star so closely that its atmosphere reaches 4,600°F.

What’s So Unique About WASP-121b?

Along with being labeled an exoplanet, the WASP-121b is also considered a “hot Jupiter.” Hot Jupiters are gas giant exoplanets that typically look similar to Jupiter but only have orbital periods lasting no more than ten days.

According to researcher David Sing of the Johns Hopkins University, “Heavy metals have been seen in other hot Jupiters before, but only in the lower atmosphere. So you don’t know if they are escaping or not.” He continues, “With WASP-121b, we see magnesium and iron gas so far away from the planet that they’re not gravitationally bound.”

WASP-121b also has a very unique appearance. Due to the exoplanet’s proximity to WASP-121, the gravitational forces are so immense that it has been stretched into the shape of a football. It is literally in danger of being torn apart.

What’s So Important About This Discover?

David Sing said that he and fellow researchers chose WASP-121b “because it is so extreme.” He adds, “We thought we had a chance of seeing heavier elements escaping. It’s so hot and so favorable to observe, it’s the best shot at finding the presence of heavy metals.”

These observations demonstrate just how quickly a planet’s atmosphere can be altered. Sing comments, “The heavy metals are escaping partly because the planet is so big and puffy that its gravity is relatively weak. This is a planet being actively stripped of its atmosphere.”

“In the case of WASP-121b, the hydrogen and helium gas is outflowing, almost like a river, and is dragging these metals with them. It’s a very efficient mechanism for mass loss.”

Bryan Brammer