After taking pictures of the deepest parts of the universe, the James Webb Space Telescope (JWST) turned the frame to focus on Earth’s closest neighbour, Mars. This includes an infrared image of the sun side of Mars (above), which can be seen on the surface of Mars in an area called the Hellas Basin which is noticeably fainter 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 more than 10 mbar, almost 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 as a darker area of the JWST.
In addition, JWST referred to the spectral analysis equipment on 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 did not 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 observational limit. This is contrary to the depths of the universe. Mars is too close and too bright, so scientists have to find a way to reduce the shutter speed as much as possible, and use special techniques to take pictures 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 not been able to determine whether this is a geological, seasonal or biological phenomenon. JWST can help analyze the amount of methane from a more comprehensive perspective on Mars, helping to confirm or rule out some theories.