The James Webb Space Telescope (JWST) has provided us with some new images that do not seem to fit with what we have seen so far. In them we can glimpse Titan, one of the moons of Saturn that most interests astronomers. Nothing is wrong with Webb, it shows us a key aspect of the satellite: its clouds.
A celebratory morning.
The excitement over the discovery can be seen in the conversations between the members of the team responsible for the discovery the day after the JWST took the new images of titan.
For example, in this email to his team from Sebastien Rodriguez, quoted in the Press release in which NASA has reported the new images: “What a wake up this morning (Paris time)! Lots of alerts in my inbox! I have gone directly to my computer and started downloading the data. At first glance, it is simply extraordinary! I think I see a cloud!”
Heidi Hammel shared his enthusiasm: “Fantastic! I love seeing the cloud and the obvious albedo markings. So I’m looking forward to seeing the specters! Congratulations to all the team!!! Thank you!”
What do the experts see in these photos?
Titan is a moon of Saturn that has some characteristics shared with Earth. Emerged lands (of water ice), rivers and lakes (of methane and other hydrocarbons), and an atmosphere with clouds (also of methane).
the key to the images It is precisely in the latter: the clouds. Two clouds can be seen at the top of the satellite. A faint one, cloud A, “at 11” and a more marked one, cloud B, “at 1”. Below in the image another similar structure can be seen, a kind of mist that has not yet been properly identified.
The two images, although they are generated from the data of the same instrument (NIRCam), show different views thanks to the use of different filters. In one we can see, disintegrated, the lower layers of the atmosphere. In the other the image of the moon as a whole, including its surface.
Also seen from Earth.
Once the two clouds were identified and located, the team looked for another telescope to be able to monitor them. They managed to gain access to the Keck observatory, located in Hawaii. With less definition but now knowing where to look, the researchers looked at the moon again after a few days.
With these new observations They were able to verify that the observed structures were moving, as would be expected from a cloud in the atmosphere. “We were concerned that the clouds were gone when we looked at Titan two days later with Keck, but to our delight there were clouds in the same positions, which seemed to have changed shape.”
Webb’s time is worth gold. The observable universe is immense and it is very far from being able to be encompassed by the eye of the telescope. 15 hours in a year may not seem like much, but in this context they are worth a lot. This is the time that has been assigned to observing Titan by the JWST.
It will take 2023 for Webb to set his sights on Titan again, but we still don’t know everything about this latest observation. Nearly a month after the images were taken, the team has still not been able to study even all the data provided by the NIRCam instrument. And the data from the infrared spectrograph is yet to be evaluated. NIRSpec.
Here it will be Webb who bears the burden of the work, since this instrument is designed to analyze, one by one, the marks that the components of the atmosphere leave on the spectrum of light that passes through the atmosphere itself. This must be done from outside ours to prevent it from affecting the measurements. These data may help to decipher what the third spot is, the one we see in the lower area of the satellite.
The bright future of Titan exploration.
Titan is one of the places that is attracting the most attention within our solar system, along with other moons such as Europa or Enceladus. In the case of Titan, the reason is its curious structure, so similar and at the same time so different of that of the Earth; as well as the abundance of hydrocarbons on its surface.
After Cassini passed through its environment, NASA has several plans to investigate the terrain, some in very preliminary phases, but others more established. In this second group we could place Dragonfly, a probe that will once again put a drone to fly on a planet that is not ours, as the Curiosity rover already did with the Ingenuity drone.