The brightest point is where the sun is directly overhead.
REPUBLIKA.CO.ID,JACARTA – Although the James Webb Space Telescope was built primarily to look back at more ancient and distant galaxies, it can also be used for a number of other scientific observations, including viewing targets in our solar system.
Webb will conduct a major study on the planet Jupiter and has imaged the planet Neptune. Reporting from Digital Trends, Sunday (09/25/2022), Webb was used to take an interesting look at our planetary neighbor, Mars.
It’s actually quite difficult for Webb to learn Mars because it is very close, and therefore very bright both in the visible part of the spectrum and in the infrared wavelengths that Webb observes. Brightness can oversaturate detectors designed to capture very faint light sources. But Webb’s NIRCam camera was able to capture the Martian surface, with two images taken at different wavelengths shown below.
The shorter wavelength image, shown above, is similar to the visible light image and shows features such as craters and basins. The image with the longest wavelength, shown below, shows how the planet radiates heat.
The brightest point is where the sun is directly overhead, with the cooler regions towards the poles. The Hellas basin also appears darker, although this is not due to the effect of temperature but to the effect of altitude and atmospheric pressure.
Webb was also able to capture Mars using his spectrometric tools. He can divide light into different wavelengths to see the composition of an object, in this case the composition of the Martian atmosphere as a whole. There are clear indications of carbon dioxide, water and carbon monoxide, and what is striking about this is how well the data fits the patterns we already know of the Martian atmosphere. This shows how effective the Web’s tools are for this type of spectrometric work and how effective the potential of Webb is when examining exoplanetary atmospheres.
This research using Webb data is still ongoing and has not been published or peer-reviewed, so it should not be considered definitive. But it shows how versatile Webb’s tools are, with more Webb data on Mars still to come.