#umbriel — Public Fediverse posts

NASA gaat op zoek naar ondergrondse oceanen in de manen van Uranus

Verschillende van de ijsmanen in de Jupiter- en Saturnus-systemen lijken interne vloeibare wateroceanen te hebben. Onze kennis van de manen van Uranus is beperkter maar een toekomstige verkenning van het Uranus-systeem heeft het potentieel om onder

https://www.kuuke.nl/nasa-gaat-op-zoek-naar-ondergrondse-oceanen-in-de-manen-van-uranus/

#Aril #manen #nasa #oberon #OndergrondseOceaan #titania #umbriel #uranus #voyager

This is a simple cylindrical projection of the same mosaic. North is at the top - the northern hemisphere was not illuminated. The equator runs horizontally through the middle. This is the form of map commonly used as input for a variety of mapping and visualization software. #maps #Uranus #Voyager #umbriel

...Where will we go tomorrow?

Reproject all the useful images to a common map projection, add them together, and what do you get? This map - the top one. The lower map is from USGS, who only used the two best views. The added coverage in my map doesn't change our ideas about Umbriel, but I like seeing a more complete map. Notice a dark streak in the USGS map - it's an artifact created by the edge of the disk on the best image. #maps #Uranus #Voyager #Umbriel

If you, like me, were new to #WundaCrater in the latest #Umbriel posts by @PhilStooke :

https://mastodon.social/@PhilStooke/113497187659806118
https://mastodon.social/@PhilStooke/113508602088708929
https://mastodon.social/@PhilStooke/113508628701204038

here's a 2017 paper on how it's most likely a cold trap for CO2 (Uranus' moons are also ~90° rotated so the equator gets the least Sun)

Sori et al: "A Wunda-full world? Carbon dioxide ice deposits on Umbriel and
other Uranian moons"
http://lunar.earth.northwestern.edu/courses/450/umbriel.pdf

#UmbrielMoon

Next, using GIS I warped the image to fit the target grid, using every grid intersection as a tie point. The image with grid overlay is warped so the grid now matches the target grid. Then repeat that process using the same tie points on the image without the grid, and hey presto, the original image is now in the desired map projection. There are analytical ways to do this but my system was built for odd-shaped worlds with no analytical solution. Here are the results.

#maps #Voyager #Umbriel

Here is the (simplified) approach to making a map of Umbriel. We have the orientation of the moon in each image and preliminary maps made before I started this work. For each image I overlaid a grid, as in these two examples. The other thing that's needed is just a plain grid in any desired map projection. I used a polar aspect of an azimuthal equidistant projection here (in other contexts I would use a simple cylindrical grid)
#maps #Uranus #Voyager #umbriel

I should say for completeness that there are three earlier views of Umbriel too but they are essentially featureless. There is a crescent view taken after the flyby but it shows no surface detail. Faint planetshine on the night side also shows nothing. Most views I show here are composites of images from multispectral sequences, combined to help suppress noise. Tomorrow we will see what sort of map emerges from this sparse dataset. #Uranus #Voyager #Umbriel

One way to understand how little we knew before spacecraft started exploring the planets is to look at old astronomy books from the 1940s or 50s. It's startling how little we could see or measure back then. Back to #Umbriel: yesterday's second image shows a bright spot in a dark patch appearing over the limb. There are only three other useful views of it and here they are. They all show that spot and dark patch but we don't learn much from them. This is all we have for a map. #Uranus #Voyager

The previous post contains the two best images we have of #Umbriel. We are so accustomed to a deluge of data these days that it's easy to forget how little we know about some worlds. I'm ignoring multispectral images here, but there's not much of it for Umbriel and Voyager was primitive compared with modern spacecraft. But I still rank it number one among planetary missions because it was the first to see see so many things. We knew practically nothing about outer planet moons before #Voyager.

Which of the large Uranian satellites is the least interesting? Umbriel? Chances are that's just because our images of it are lower resolution. Admittedly in Voyager images it doesn't look very exciting. There is that oddly bright crater floor... but imagine flying past Umbriel with the instruments on New Horizons - it would probably look great. Here are two views of it, the best we can do. There are lots of craters and hints of dark streaks.
#Uranus #Voyager #Umbriel

𝗪𝗜𝗞𝗜𝗣𝗘𝗗𝗜𝗔'𝗦 𝗙𝗘𝗔𝗧𝗨𝗥𝗘𝗗 𝗔𝗥𝗧𝗜𝗖𝗟𝗘

✧ Umbriel ✧

Umbriel is the third-largest moon of Uranus. It was discovered on October 24, 1851, by William Lassell. Named after a character in the 1712 poem The Rape of the Lock by Alexander Pope, Umbriel is composed mainly of ice with a substantial fraction of rock. It may be differentiated into a rocky core and an icy mantle. Its surface, the darkest among Uranian moons, appears to h...

#Umbriel #Uranus #Wikipedia
https://en.wikipedia.org/wiki/Umbriel_(moon)

Because Uranus orbits the Sun almost on its side, and Umbriel orbits in the planet's equatorial plane, it has some extreme seasons. Both northern and southern poles spend 42 years in complete darkness, and another 42 years in continuous sunlight.

10 things you might not know about Umbriel, a moon of Uranus:

https://topicaltens.blogspot.com/2020/10/24-october-umbriel.html

#Facts #Space #Uranus #Umbriel #Moons #SolarSystem

4 out of 5 #Uranus #moons likely to have #ocean under crust
A preview of what #UranusOrbiter and Probe might find in the 2040s
The #water is believed to be located between the core and icy crusts in oceans 30km deep for moons Ariel and #Umbriel, and less than 50m for #Titania and #Oberon.
It's not uncommon to find water in dwarf #planets and moons. For example, #dwarfplanets #Ceres and #Pluto, as well as #Saturn's moon #Mimas, have all shown evidence of liquid water.
https://www.theregister.com/2023/05/05/four_out_of_five_uranus/