The James Webb Space Telescope (JWST) took its first images of Mars, displaying infrared light from the red planet with high sensitivity.
The first images and spectra of the James Webb Space Telescope Mars Monday (September 19) in Europlanet Science Conference (Opens in a new tab) (EPSC) 2022. Images and measurements were made on September 5, 2022 from a JWST site approximately 1 million miles (1.6 million km) from Mars.
Images of the visible disk of Mars – the side of the planet illuminated the sun Facing the Telescope – Captured by Webb Near Infrared Camera (Opens in a new tab) (NIRCam) and could provide planetary scientists with a unique view of Earth’s nearby neighbor, providing data that can be used in conjunction with observations made by rover vehicles such as perseverance NASA The character is in the orbit of Mars.
Because Mars is relatively close and so bright, it’s not the easiest object for JWST—designed to see incredibly distant and faint objects—to visualize.
“Mars is very bright, and the challenge is how to see it,” Giuliano Leutsi, principal investigator at NASA’s Planetary Systems Laboratory at Goddard Space Flight Center, said at an EPSC press conference marking the release of the images.
To prevent bright infrared light from Mars from blinding the JWST instruments, the scientists used very short exposures to observe the Red Planet. This means measuring only some of the light that has reached the JWST detectors and then applying special methods to analyze the collected data.
“We can see this amazing resolution, we have the diffraction limit of a space telescope in the infrared, which is fantastic. We can see the entire planet,” Yusi continued.
Watching Mars around the clock
JWST was able to capture the images and spectra with the spatial resolution that astronomers need to study short-term phenomena such as weather patterns on Mars, dust storms, and even changes caused by the planet’s seasons.
In addition, the Webb telescope can capture events that occur at different times during the Martian day — during the day, at sunset and during the night — in a single observation.
The first images of Mars taken by JWST show a region in the eastern hemisphere of the planet at two different wavelengths of light.
Reflected sunlight dominates the short-wavelength image and shows details of the surface of Mars that resemble features seen in visible light. These features include Huygens Crater, an impact crater 280 miles (450 kilometers) wide, and dark igneous rocks in Syrtis Major Planum.
The Webb Space Telescope’s NIRCam camera captured the light that Mars emits at longer infrared wavelengths as it loses heat. The brightness of this light is related to the temperature and atmosphere of Mars, where the brightest and warmest region is located the sun It is almost above the planet.
The brightness diminishes toward the Martian polar regions that get less sunlight, and in the northern half of the planet which is currently in the middle of the Martian winter.
However, the amount of light reaching JWST is not only related to the temperature of the planet. Images collected by the telescope can also give hints about the chemical composition of Mars atmosphere and the surface.
Atmospheric evidence in the Hela Basin
Analyzing the spectrum of light detected from Mars with data collected by the James Webb Space Telescope can help astronomers determine the composition of its atmosphere and surface.
After analyzing the JWST images, Liuzzi and his team found that the 1,200-mile-wide (1,930 km) Hellas Basin appears darker than its surroundings, even at the hottest time of a Martian day in that region.
“One of the cool things is that you can see a dark spot that’s a basin on Mars. We weren’t expecting that. We were seeing something very bright, but it’s getting darker,” Liuzi said. “This is actually not a thermal effect in Hellas.”
The dimming we see in the well-preserved effect structure is the result of light passing through Mars atmosphere Carbon dioxide absorbs it.
“The Hellas Basin is lower in elevation, and therefore experiences higher air pressure,” the Goddard researcher explains. “High pressure suppresses thermal emission in this specific wavelength range due to an effect called pressure broadening. It would be very interesting to separate these competing effects in this data.”
The new images also demonstrate the ability of the James Webb Space Telescope to study Mars using a technique called spectroscopy on measurements taken with the telescope’s near-infrared spectrometer (NIR) a tool.
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Because chemical elements absorb and emit light at very specific wavelengths, planetary scientists can use spectroscopy to study the “fingerprints” that different chemicals leave in light passing through a planet’s atmosphere to determine its composition.
The preliminary results obtained by scientists show spectral features encoded with information about Martian dust, ice clouds, the composition of the atmosphere and the type of rocks on the planet’s surface.
Observations from JWST must be able to determine the presence of water, carbon dioxide, carbon monoxide, and other chemical compounds.
Liuzzi recalled the discussion about attending Methane on Mars, with initial ground observations and roving vehicles providing evidence for this compound, albeit sporadically. While ExoMars Trace Gas Orbiter (TGO) measurements have not been able to confirm this, observations from Earth are also complicated by methane in the Our planet’s atmosphereLiuzzi believes JWST’s feedback can make the difference.
“The big mystery is that the surface roving vehicles and monitoring data left a gap between zero and 10 kilometers [6 miles]He said “Now we have James Webb, we can see the full column [of the atmosphere] Down to the surface where the rover is. So we introduced a new way to solve this puzzle.”
Liuzi added that methane is important because it can tell planetary scientists about a lot of geological processes on Mars, including whether something big hit the Red Planet from space recently. Methane could also indicate biological activity in the planet’s ancient history.
“That’s our main goal at the moment,” Liuzi said.
The JWST team is currently producing a paper that presents its findings for peer review.