On August 24, a vital instrument aboard the James Webb Space Telescope (JWST) experienced a malfunction that prompted the mission team to take it offline. The issue occurred when the Mid-Infrared Instrument (MIRI) experienced increased friction in one of its wheels in Medium Resolution Spectroscopy (MRS) mode. The mission team took MIRI offline while they attempted to diagnose the problem, leaving the observatory to continue making observations in other modes.
This happened shortly after Webb was hit by a large micrometeoroid in late May that damaged one of his major mirror segments. Fortunately, the damage this caused won’t impair the telescope’s performance, and the mission team announced earlier this month that it had restored the MIRI to operational status. With everything in the green, Webb once again turned its infrared optics to the cosmos and acquired breathtaking images. This includes a new image of Titan, Saturn’s largest moon, which recently surfaced online.
The image was processed and uploaded to Twitter by Michael Radke, a Ph.D. student who studies planetary atmospheres using laboratory photochemistry experiments at Johns Hopkins University (JHU). According to Radke, the image was acquired between November 4 and 5, the scale of which he doubled and added red, green and blue to represent different wavelengths (R = 4.8 um, G = 2.1 µm, B = 1.4 µm). These values were based on the Visible and Infrared Mapping Spectrometer (VIMS) from the Cassini mission.
Delete all announcements on the universe today
Join our Patreon for as low as $3!
Get the ad-free experience for life
These colors appear to match the absorption spectrum of carbon monoxide (green), methane (blue), and nitrogen (red), the gases that make up the majority of Titan’s atmosphere. Titan also appears to be illuminated from the upper left corner of the image, giving the impression of a sunrise. Planetary scientist, author and space journalist Emily Lakdawalla suggested that the source could be light reflected from Saturn’s atmosphere. This image also gives an overview of the types of scientific operations Webb will drive with Titan and other bodies in our solar system.
Its powerful instruments and imaging capabilities in the near and mid-infrared will allow astronomers to study the chemical composition of the atmospheres in detail. Titan is of particular interest because it is the only moon in our atmosphere with a substantial atmosphere – where the air pressure is about 50% higher than Earth’s. Like Earth, TItan’s atmosphere is mostly nitrogen gas (94%), with hydrocarbons like methane making up the second largest fraction (5.65%).
Titan is the only other body in the solar system with a cycle of precipitation and evaporation. While Earth has a water cycle, Titan has a methane cycle, where methane forms clouds in the moon’s atmosphere, falls to the surface as rain, and replenishes methane lakes. Additionally, Titan’s atmosphere is rich in chemical processes as hydrocarbons are broken down by solar radiation into their constituents (i.e. carbon, hydrogen, oxygen and nitrogen) and form then new molecules that percolate and settle on the surface.
Titan’s atmosphere and surface also have something that no body other than Earth has: a rich prebiotic environment and organic chemistry. For this reason, astrobiologists have suspected that Titan might be one of the most promising places to search for extraterrestrial life. For these reasons, Webb needs his instruments working, especially MIRI and the Near Infrared Spectrograph (NIRSpec). These will obtain high-precision spectra of Titan’s atmosphere to observe these molecules and processes at work.
These studies will build on previous efforts by the joint NASA-ESA Cassini-Huygens mission, which studied Saturn and its satellites from 2004 to 2017. The orbiter and lander have studied Titan’s atmosphere in depth and have made many profound discoveries. The more detailed information Webb will obtain will be used to study Titan’s seasonal cycles, leading to more detailed climate models. This will help pave the way for missions like NASA’s Dragonfly rotorcraft to be launched for Titan in 2027, arriving in the 2030s.
#JWST #fully #operational #images #Saturns #Moon #Titan