James Webb Space Telescope has made remarkable progress. It can see farther into space and time than any telescope before it, which is an incredible feat. But it’s also showing us the Universe closer to home… and now it’s turned its gold-plated eye to Earth’s next-door-neighbor, Mars.
The resulting images show Mars in a very different light – infrared, in fact – giving us information about the red planet that we wouldn’t be able to see with our own naked eyes.
Thermal radiation is heat that emits infrared light. This information is a lot about Mars’s temperature. But scientists can also use these tidbits to better understand another planet so similar to ours.
The view is breathtaking, naturally.
JWST has some difficulties imaging objects close to home. It is the largest telescope to have been launched into space. It was designed to detect dimmest light coming from distant objects. Mars is like a furnace compared to the other telescopes.
Scientists had to use techniques to compensate for the brightness to avoid oversaturation. Data analysis was adjusted to account for the short exposure times.
It was well worth the effort: A map of Mars’ side, viewed through the telescope using two wavelengths infrared light. The image at 2.1 microns is dominated in part by the sunlight reflecting off Mars’ surface. This makes it very similar to optical wavelengths.
The image’s 4.3 microns resolution is dominated by thermal radiation emanating from Mars. It is brightest near the Sun, which is approximately in line with the planet. This is where a planet’s atmosphere is typically warmest.
However, heat is not the only source for infrared light at that wavelength. The bottom right corner of the brightest area in this wavelength shows a dark smear. This is actually caused by a feature on Mars’ surface. It’s an enormous impact basin called Hellas Planitia – it’s one of the largest craters on Mars, and the entire Solar System.
The atmosphere on Mars is 96% carbon dioxide. This absorbs light. This is because the atmosphere is thicker over the Hellas Planitia to allow for infrared wavelengths to be observed.
“This is not a thermal effect at Hellas.” SaysGeronimo Villanueva (NASA’s Goddard Space Flight Center), who created the observations.
“The Hellas Basin, which is lower in altitude, experiences higher air pressure. This higher pressure results in a reduction of thermal emission at this wavelength range. [4.1-4.4 microns]Pressure broadening is an effect that causes this. It will be fascinating to separate these competing effects from these data.
This is the near-infrared wavelength of Mars. It shows the more intricate breakdown of the planet’s atmosphere.
Scientists have so far been able to easily identify carbon dioxide, carbon monoxide and water in Mars’ atmosphere.
But, the analysis is ongoing and we won’t know the details of these new data until the team releases their findings in an published paper. They are currently working on that. This will require the following: peer reviewWe are still in the publication process but we are excited to see what additional information this amazing telescope can provide about such a well-studied world.
