The first photos and infrared spectra of Mars from the James Webb Space Telescope (JWST) were made public by the European Space Agency (ESA). On September 5, 2022, the Webb telescope acquired its first pictures and spectra of the red planet.
Webb is located near the second Sun-Earth Lagrange point, at 1.5 million kilometers from Earth (L2). The area of Mars’ sunny side towards the telescope, known as the viewable disc, is visible from the telescope’s vantage point. As a result, JWST is able to record spectra and pictures with the precise precision required to investigate transient processes. Dust storms, weather patterns, and seasonal shifts are a few of these occurrences.
This might not seem spectacular for a telescope used to find far-off dim objects, but it is. In both visible and infrared light, Mars is among the brightest objects in the night sky due to its near proximity to the Earth. However, due to the sensitivity of Webb’s equipment, the intense infrared light from Mars is practically blinding, leading to a phenomenon known as “detector saturation.”
To get around this, scientists must employ specialized detection methods, such as extremely brief exposure times and detecting just a portion of the light that reaches the detectors. They then arrived at the picture using unique data analysis techniques.
The Near-Infrared Camera (NIRCam) on JWST’s initial Mars photos shows a portion of the planet’s eastern hemisphere at two distinct wavelengths. In the picture above, two Webb NIRCam sensor fields are superimposed on the left side of a surface reference map captured by NASA’s Mars Global Surveyor.
Mars’ spectra were recorded by the James Webb Space Telescope. (Image credit: Mars JWST/GTO team, NASA, ESA, CSA, STScI)The Mars Webb photos reveal variations in brightness over a wide range of wavelengths from location to location on the planet at a certain time and date. However, the spectrum shows how the planet’s overall brightness varies subtly over hundreds of distinct wavelengths. To learn more about the atmosphere and surface of the planet, astronomers will examine spectrum characteristics.