Web Telescope Captures Mars' Sunset and Dust Clouds [Reading Science]

US NASA to Unveil First Mars Image at European Planetary Science Congress on 19th
Includes Unprecedented Ultra-High-Resolution Detailed Observations
Innovative Results in Atmosphere-Surface Composition Studies, Focused on Confirming Methane Presence

[Asia Economy Reporter Kim Bong-su] "We have observed the sunset and dust clouds on Mars." The James Webb Space Telescope (JWST), which has been providing increasingly astonishing celestial images, has now released ultra-high-definition images of Mars, the planet closest to Earth.

The U.S. National Aeronautics and Space Administration (NASA) Planetary Science Institute unveiled images taken by JWST from 1.6 million kilometers away from Mars on the 5th, using the Near Infrared Camera (NIRCam), at the European Planetary Science Congress (EPSC) held in Granada, Spain, on the 19th (local time).

Mars is the closest planet to Earth and shines very brightly, but ironically, this brightness made it difficult to observe with JWST. This is because JWST is designed to capture distant, dark, and faint celestial bodies. NASA scientists minimized the exposure of JWST’s optical equipment and observed Mars for a very short period to create the images. They were able to observe not only mid- to long-term changes such as weather patterns, dust storms, and seasonal variations on Mars but also daily phenomena like sunsets, daytime, and nighttime occurring hour by hour.

The photos released by NASA this time include two types of near-infrared images: short-wavelength and long-wavelength. The short-wavelength images captured the sunlit eastern hemisphere of Mars, revealing details such as the approximately 450 km-wide Huygens impact crater and the black volcanic rocks on the Syrtis Major Planum.

Additionally, the near-infrared camera of the Webb telescope captured the cooling phenomenon after sunset through long-wavelength infrared images, confirming that the area directly under the sun is the hottest and brightest. Conversely, the northern hemisphere of Mars, currently in the midst of winter, and the polar regions with less sunlight exposure appeared dark.

Moreover, the images provide information about the chemical composition of Mars’ atmosphere and surface. For example, NASA’s research team confirmed that the Hellas Basin, about 1,930 km wide, appeared darker than surrounding areas even during the hottest time of day, midday. This unexpected result is explained by the research team as light reflected from the surface being absorbed by carbon dioxide as it passes through the atmosphere in that region.

A team member stated, "The Hellas Basin is located at a low altitude, so the atmospheric pressure is higher," adding, "It is very interesting that the high atmospheric pressure seems to suppress thermal emission in certain wavelength ranges."

The power of planetary observation technology through spectroscopy was also confirmed. Spectroscopy is a technique that analyzes the chemical composition of a planet and its atmosphere by observing how light reflected from the planet’s surface refracts and changes wavelength as it passes through the atmosphere. Through these images, NASA’s research team was able to identify Mars’ dust and ice clouds, atmospheric components, and types of surface rocks. The team expects that further observations with JWST will clarify the presence of water, carbon dioxide, carbon monoxide, and other chemical substances. In particular, it is anticipated to resolve the controversy over the presence of methane, which has not been confirmed by existing ground-based telescopes or rovers.

A team member explained, "Observations from surface rovers or orbiters had many limitations, but now with the Webb telescope, we can establish a new method to confirm the presence of methane," adding, "The presence of methane will provide important clues not only about Mars’ geological formation processes but also about the possibility of ancient life."