After taking pictures of the deepest parts of the universe, the James Webb Space Telescope (JWST) turned the frame to focus on Earth’s nearest neighbor, Mars. This includes an infrared photo of the sun-facing side of Mars (above), which can be seen on the surface of Mars in an area called the Hellas Basin that is noticeably weaker than elsewhere on the surface. This is mainly because the height difference between the edge and the bottom of the Greek Basin is as high as 9 kilometers, which makes the pressure in the Greek Basin exceed 10 mbar, nearly double the 6.1 mbar above the base level. This causes the thermal radiation in the basin to be suppressed by the atmosphere, which appears to be a darker area from the JWST.
In addition, JWST also pointed the spectral analysis equipment at Mars, and the spectral absorption lines representing carbon dioxide, water vapor and carbon monoxide can be seen from the preliminary data. As for the detailed analysis, and whether there is anything that astronomers didn’t know, it will be published by NASA in the future.
In fact, although Mars is the closest target to Earth, for JWST, it may be the limit of observation. This is just the opposite of the depths of the universe. Mars is too close and too bright, so scientists must find a way to shorten the shutter speed as much as possible, and use special techniques to take pictures in order to avoid “overexposure”. In the future, JWST should also occasionally turn its lens to Mars to capture changes in its atmospheric composition for long-term comparisons. Perhaps the most important of these is methane—the mysterious appearance and disappearance of methane on Mars is known, but scientists have been unable to determine whether this is a geological phenomenon, a seasonal phenomenon, or a biological phenomenon. JWST can assist in analyzing the amount of methane from a more comprehensive perspective on Mars, helping to confirm or rule out some hypotheses.