(CNN) — The main goal of the James Webb Space Telescope is to detect the faint light from distant galaxies, but it recently observed one of the brightest objects in the night sky: Mars.
The space observatory captured its first images and data of the red planet on September 5.
There are multiple orbiters on Mars, as well as the Curiosity and Perseverance rovers that roam the surface and regularly send back data, but Webb’s infrared capabilities bring another perspective that could reveal more details about the Martian surface and atmosphere.
Located 1.6 million kilometers from Earth, Webb can see the sunlit side of Mars facing the space telescope, putting the observatory in the perfect position to spy on the planet’s seasonal changes. dust storms and weather all at once.
The telescope is so sensitive that astronomers had to make adjustments to prevent the blinding infrared light from Mars from saturating Webb’s detectors. Instead, Webb observed Mars using very short exposures.
The new images show the eastern hemisphere of Mars in different wavelengths of infrared light. On the left, a reference map of the hemisphere captured by the Mars Global Surveyor mission, which ended in 2006.
The upper right Webb image shows sunlight reflecting off the Martian surface, showing Martian features such as Huygens Crater, dark volcanic rock, and Hellas Planitia, a huge impact crater on the Red Planet that stretches across over 2,000 kilometers long.
The lower right image shows thermal emission from Mars, or the light emitted by the planet when it loses heat.
The brightest areas indicate the hottest spots. In addition, the astronomers detected something else in the thermal emission image.
When thermal light passes through the Martian atmosphere, some of it is absorbed by carbon dioxide molecules. This phenomenon has made the plain appear darker.
“It’s not actually a thermal effect in Hellas,” Geronimo Villanueva, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, said in a statement.
“The Hellas Basin is at a lower altitude, and therefore experiences higher air pressure,” said Villanueva, who is also the principal investigator for the Mars and Ocean Worlds surveys for the Webb telescope. “That higher pressure leads to a suppression of thermal emission in this particular wavelength range due to an effect called pressure broadening. Unraveling these opposing effects in these data will be very interesting.”
Using Webb’s powerful capabilities, Villanueva and his team also captured the first near-infrared spectrum of Mars.
The spectrum indicates more subtle differences in brightness on the planet, which could highlight aspects of the Martian surface and atmosphere. Initial analysis has revealed information about the ice clouds, dust, rock types on the surface, and the composition of the atmosphere contained in the spectrum. There are also signatures for water, carbon dioxide, and carbon monoxide.
The NASA research team will share more information about Webb’s observations of Mars in a study that will be submitted for future review and publication. And the Mars team hopes to use Webb’s capabilities to detect differences between regions of the Red Planet and look for gases like methane and hydrogen chloride in the atmosphere.