James Webb takes a closer look at Mars – ScienceTimes

After Thursday, it’s now March. (Shortcut to related article – “James Webb Takes a Closer Look at Jupiter”) The James Webb Space Telescope, which digs into the universe one by one thanks to the use of infrared rays, has become a hot topic by closely observing Mars, one of the closest celestial bodies to Earth .

Earth’s brother planet – Mars

Mars is the fourth planet in the solar system and is also known as the red planet because of its red color due to iron oxide. Because of its size similar to Earth, it is also known as Earth’s brother planet along with Venus. Although it has only been a few decades since humans began to develop and explore space on a full scale, Mars is one of the most recognizable celestial bodies in name and reality. At the same time, it is also one of the most explored planets among all the planets of the solar system. The United States, Europe, China and India have already sent Mars orbiters, and more than five rovers have explored or are currently exploring Mars. Even now, man-made drones fly over Mars. Therefore, Mars was also the first planet for humans to fly from another planet.

Mars is basically a very harsh environment for life to exist. This is because the surface temperature is low, the atmosphere is thin, and the planet’s magnetic field is for some reason so thin that it cannot block the solar wind. The question of whether life existed on Mars in the past is still a matter of time and research, but liquid water has already been discovered on Mars. Also, Mars is the most likely candidate for life on Earth to migrate. (See related article – “What the discovery of ‘liquid water’ on Mars means”)

James Webb Takes a Closer Look at Mars

The James Webb Space Telescope captured Mars on 5 September while observing the further and darker universe using the Near Infrared Camera (NIRCam). The first image of Mars, first seen by the eye of James Webb, presents a series of surprises. James Webb’s high-resolution image captures a relatively close-up image of Mars in great detail, revealing the reflective and thermal properties of the planet with great sensitivity. (Go to high resolution image)

Take a closer look at Mars ⓒ NASA, ESA, CSA, STScI, JWST/GTO Mars Team

The picture on the left is a simulated image of the southern summer of Mars, predicted based on historical NASA data and results from the Mars Orbiter Laser Altimeter (MOLA). This image shows the appearance and orientation of the planets at the date and time of James Webb’s observation of Mars. The central longitude is about 80 degrees east, and the axis is inclined about 25 degrees perpendicular to the plane of the orbit.

The image on the left shows the topographical features of Mars and the color of its surface, typically seen in reflected sunlight. The dark volcanic region of Syrtis Major, the complex impact crater Huygens crater, and the Hellas Basin, the largest impact structure on Mars, are prominent. The scale bar represents 4,210 km, the blue outline represents the field of view of the upper right image and the white outline represents the field of view of the lower right image.

The top right image shows the image of Mars taken using the F212 near-infrared camera filter with a wavelength of 2.1 micrometers (expressed in micrometers, or microns). The dark volcanic rocks of Sirtis Major, the bright rings of Huygens Crater, and the Hellas Basin covered in a layer of bright dust rings are clearly visible.

The lower right image is an image taken with another near-infrared camera at the same time, showing the light emitted using a wavelength of about 4.3 micrometers and an F430M filter. In this image, temperature differences with latitude and time and darkening due to atmospheric effects are clearly captured. Measured surface brightness is highest in the southern part of Mars (yellow) and decreases markedly towards the wintering northern hemisphere and evening hours in the western hemisphere.

The measured darkness of brightness in the Hellas Basin is not due to the low temperature, but because it is more than 7 km deep and creates a higher pressure than the surrounding land. Because of this, the heat dissipation was weakened and the brightness was measured to be low. In addition, some of the light with a wavelength of 4.3 micrometers emitted from the basin is absorbed by molecules such as carbon dioxide in the Martian atmosphere.

Near-infrared spectrum – reveals the chemical and physical properties of the Martian surface and atmosphere

At the same time, the James Webb team imaged the near-infrared spectrum of Mars with a near-infrared spectrometer (NIRSpec). It shows the chemical and physical properties of the surface and atmosphere of Mars. (Go to high resolution image)

The near-infrared spectrum shows the chemical and physical properties of the Martian surface and atmosphere. ⓒ NASA, ESA, CSA, STScI, JWST/GTO Mars Team

Data are shown in white and are unfortunately not continuous by wavelength as they were collected using six different high resolution spectrometer modes (lattice mode), each covering a different wavelength range. Purple represents the best model that best fits this data among the simulated observational results to which other known Mars features are applied. FYI, the planetary spectrum generator(Planetary Spectrum Generator)Build an optimal model using tools such as

This spectrum shows a combination of sunlight reflected from the surface and atmosphere of Mars, and light re-emitted from the planet. It shows that light is mainly reflected at wavelengths from 1 to 3 micrometers and emitted mainly at wavelengths from 3 to 5 micrometers. Both reflect and emit light of various wavelengths passing through the Martian atmosphere and affect the brightness and shape of the spectrum in different ways. In particular, the deep valley-shaped spectrum shows absorption lines that occur when it is blocked by gases such as carbon dioxide, water and carbon monoxide. Other details, such as the width and depth of the spectrum, show specific information about the Martian surface, such as the amount of dust and clouds.

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