Keep in mind: This post highlights information from Webb science in progress, which has actually not yet been through the peer-review procedure.
Conor Nixon, is a planetary scientist at the NASA Goddard Space Flight Center in Greenbelt, Maryland, and works as Principal Investigator on the Webb Cycle 1 Guaranteed Time Observation program 1251.
Co-Investigator Heidi Hammel is a planetary researcher. She is Vice President for Science at AURA and leads the JWST Solar System Science Group.
Co-Investigator Sébastien Rodriguez is a planetary researcher at the Institut de Physique du Globe de Paris at the Universite Paris Cité, in France.
Imke de Pater is an Emeritus teacher of astronomy at the University of California, Berkeley, and is lead of the Keck Titan Observing Team.
Katherine de Kleer is an Assistant Professor of Planetary Science and Astronomy at Caltech in Pasadena, California, and is a member of the Keck Titan Observing Team.
Juan Lora is an Assistant Professor of Earth & & Planetary Sciences at Yale University in New Haven, Connecticut.
Maël Es-Sayeh is a graduate student in planetary sciences at Institut de Physique du Globe de Paris of the Universite Paris Cité, in France.
Images of Saturns moon Titan, recorded by the James Webb Space Telescopes NIRCam instrument November 4, 2022. Left: Image using F212N, a 2.12-micron filter delicate to Titans lower atmosphere. Science: JWST Titan GTO Team
On the morning of Saturday, November 5, a worldwide team of planetary researchers woke up with excellent pleasure to the first Webb pictures of Saturns largest moon, Titan. Here, Principal Investigator Conor Nixon and others on the Guaranteed Time Observation (GTO) program 1251 group utilizing Webb to examine Titans atmosphere and environment describe their preliminary reactions to seeing the information.
Saturns biggest moon Titan is the only moon in the planetary system with a dense environment, and it is likewise the only planetary body other than Earth that presently has seas, lakes, and rivers. Unlike Earth, however, the liquid on Titans surface area is made up of hydrocarbons consisting of methane and ethane, not water. Its atmosphere is filled with thick haze that obscures noticeable light reflecting off the surface.
Titans atmosphere is incredibly intriguing, not only due to its methane clouds and storms, but also because of what it can tell us about Titans past and future– consisting of whether it constantly had an atmosphere. Cloud A appears to be turning into view while Cloud B appears to be either dissipating or moving behind Titans limb (around toward the hemisphere facing away from us). Detecting clouds is amazing due to the fact that it verifies long-held forecasts from computer models about Titans climate, that clouds would form readily in the mid-northern hemisphere throughout its late summer season when the surface area is warmed by the Sun.
Our Webb Titan team lead Conor Nixon from NASAs Goddard Space Flight Center wrote to Imke de Pater at University of California, Berkeley, and Katherine de Kleer at the California Institute of Technology (Caltech), who have extensive experience utilizing Keck: “We just got our first images of Titan from Webb, taken last night. Imke de Pater commented: “We were concerned that the clouds would be gone when we looked at Titan 2 days later with Keck, however to our pleasure there were clouds at the very same positions, looking like they had altered in shape.”
We had waited for years to utilize Webbs infrared vision to study Titans atmosphere, including its fascinating weather condition patterns and gaseous structure, and also see through the haze to study albedo features (dark and intense spots) on the surface. Titans atmosphere is extremely intriguing, not just due to its methane clouds and storms, but also because of what it can inform us about Titans past and future– including whether it constantly had an atmosphere. We were definitely happy with the preliminary outcomes.
Staff member Sebastien Rodriguez from the Universite Paris Cité was the first to see the new images, and notified the rest people by means of e-mail: “What a wake-up today (Paris time)! Lots of informs in my mailbox! I went directly to my computer and started simultaneously to download the information. In the beginning look, it is just amazing! I think were seeing a cloud!” Webb Solar System GTO Project Lead Heidi Hammel, from the Association of Universities for Research in Astronomy (AURA), had a similar reaction: “Fantastic! Love seeing the cloud and the obvious albedo markings. So looking forward to the spectra! Congrats, all!!! Thank you!”
Development of clouds on Titan over 30 hours between November 4 and November 6, 2022, as seen by Webb NIRCam (left) and Keck NIRC-2 (right). Titans trailing hemisphere seen here is turning from left (dawn) to right (evening) as seen from Earth and the Sun. Cloud A seems turning into view while Cloud B appears to be either moving or dissipating behind Titans limb (around towards the hemisphere dealing with away from us). Clouds are not lasting on Titan or Earth, so those seen on November 4 may not be the same as those seen on November 6. The NIRCam image utilized the following filters: Blue= F140M (1.40 microns), Green= F150W (1.50 microns), Red= F200W (1.99 microns), Brightness= F210M (2.09 microns). The Keck NIRC-2 image utilized: Red= He1b (2.06 microns), Green= Kp (2.12 microns), Blue= H2 1-0 (2.13 microns). Credit: NASA, ESA, CSA, W. M. Keck Observatory. A. Pagan (STScI). Science: Webb Titan GTO Team
By comparing various images caught by Webbs Near-Infrared Camera (NIRCam), we soon validated that an intense area noticeable in Titans northern hemisphere was in reality a large cloud. Identifying clouds is amazing due to the fact that it confirms long-held forecasts from computer models about Titans environment, that clouds would form easily in the mid-northern hemisphere throughout its late summer season when the surface area is warmed by the Sun.
We then understood it was essential to find out if the clouds were moving or altering shape, which might expose info about the airflow in Titans environment. Our Webb Titan team lead Conor Nixon from NASAs Goddard Space Flight Center wrote to Imke de Pater at University of California, Berkeley, and Katherine de Kleer at the California Institute of Technology (Caltech), who have comprehensive experience utilizing Keck: “We simply got our first images of Titan from Webb, taken last night. We were wondering about a quick response follow-up observation on Keck to see any evolution in the cloud?”
The goal was to penetrate Titan from its stratosphere to surface area, to try to capture the clouds we saw with Webb. Imke de Pater commented: “We were concerned that the clouds would be gone when we looked at Titan 2 days later on with Keck, however to our delight there were clouds at the exact same positions, looking like they had actually changed in shape.”
After we got the Keck information, we relied on climatic modeling specialists to assist analyze it. One of those specialists, Juan Lora at Yale University, said: “Exciting undoubtedly! Im delighted were seeing this, given that weve been forecasting a good little bit of cloud activity for this season! We cant be sure the clouds on November 4th and 6th are the exact same clouds, however they are a confirmation of seasonal weather patterns.”
The group also gathered spectra with Webbs Near-Infrared Spectrograph (NIRSpec), which is offering us access to many wavelengths that are blocked to ground-based telescopes like Keck by Earths atmosphere. This data, which we are still analyzing, will enable us to actually probe the structure of Titans lower environment and surface area in manner ins which even the Cassini spacecraft could not, and to find out more about what is causing the intense function seen over the south pole.
We are anticipating even more Titan data from NIRCam and NIRSpec along with our very first data from Webbs Mid-Infrared Instrument (MIRI) in May or June of 2023. The MIRI data will reveal an even majority of Titans spectrum, including some wavelengths we have actually never seen prior to. This will provide us details about the complex gases in Titans atmosphere, in addition to essential clues to figuring out why Titan is the only moon in the Solar System with a thick environment.
Maël Es-Sayeh, a graduate trainee at the Universite Paris Cité, is particularly looking forward to these observations: “I will be using the data from Webb in my PhD research study, so its extremely amazing to finally get the genuine data after years of simulations. I cant wait to see what will be available in part 2 next year!”
About the Authors
By Margaret W. Carruthers, Space Telescope Science Institute
December 3, 2022
Titan is larger than Earths moon, and even larger than the world Mercury. Titan is the only moon in our solar system that has clouds and a thick environment. Apart from Earth, Titan is the only place in our planetary system understood to have liquids on its surface area.