(ORDO NEWS) — The James Webb Space Telescope has made incredible progress, looking further into space and time than any other telescope before it.
But he’s also showing us the universe closer to home… and now he’s turned his gilded eye to Earth‘s closest neighbor, Mars.
The resulting images show Mars in a completely different light – infrared, in fact – giving us information about the red planet that we wouldn’t be able to see with the naked eye.
Given that heat emits infrared light (what we call thermal radiation), a lot of this information relates to the temperature of Mars, but there are other tidbits that scientists can use to better understand a planet so similar to ours, but so unlike ours.
And, of course, the view is amazing.
It’s actually quite difficult for JWST to portray something close to home. It is the most powerful telescope ever launched into space, designed to be sensitive enough to detect extraordinarily dim light from the most distant objects in the universe. Compared to them, Mars burns like a furnace.
To avoid the oversaturation that usually occurs due to such brightness, scientists making observations and processing data had to use compensation methods. The exposure time was incredibly short and the data analysis was adjusted accordingly.
The result was worth it: a map of the side of Mars seen by a telescope in two wavelengths of infrared light. At 2.1 microns, the image is dominated by sunlight reflecting off the surface of Mars, so what we see is very similar to what we might see at optical wavelengths.
At a wavelength of 4.3 microns, the image is dominated by thermal radiation. the radiation of the Martian atmosphere, which is brightest where the Sun is almost directly in line with the planet. As a rule, this is the place where the planetary atmosphere is the warmest.
But heat is not the only source of infrared light at this wavelength. A dark spot can be seen in the lower right corner of the brightest area at that wavelength; it is actually caused by a feature on the surface of Mars. This huge impact basin called Hellas Planitia is one of the largest craters on Mars and the entire solar system.
The atmosphere of Mars is 96 percent carbon dioxide, which absorbs light. And the atmosphere over the Hellas Plains is thick enough that it can be seen in the infrared.
“It’s not really a thermal effect in Hellas,” says astronomer Geronimo Villanueva of NASA‘s Goddard Space Flight Center, who engineered the observations.
“The Hellas Basin is at a lower altitude and therefore experiences higher air pressure. This higher pressure leads to suppression of thermal radiation in that particular wavelength range [4.1-4.4 microns] due to an effect called pressure expansion. It will be very interesting to parse these competing effects in this data.”
He is referring to the near-infrared spectrum of Mars, which shows a more accurate and detailed breakdown of the composition of the planet’s atmosphere and surface as certain wavelengths are muted or enhanced by the absorption and re-emission of light by certain molecules.
So far, scientists have been able to easily identify carbon dioxide, carbon monoxide, and water in the Martian atmosphere.
However, the analysis is ongoing and we won’t know what details this new data reveals until the team is ready to publish their findings in a published paper they are currently working on.
It’s due for peer review and publication, but we’re thrilled to see what new information this amazing telescope can reveal about such a well-studied planet.
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