The make-up and temperature of Uranus’s rings
New radio images taken by the ground-based telescopes by the ALMA and VLT telescopes in Chile have allowed scientists to better determine the make-up and temperature of the rings of Uranus.
The image above is from their paper. From the caption:
Images of the Uranian ring system at 3.1 mm (ALMA Band 3; 97.5 GHz), 2.1 mm (ALMA Band 4; 144 GHz), 1.3 mm (ALMA Band 6; 233 GHz), and 18.7 μm (VLT VISIR; 100 THz)…The planet itself is masked since it is very bright compared to the rings.
From the article above:
The new images taken by the Atacama Large Millimeter/submillimeter Array (ALMA) and the Very Large Telescope (VLT) allowed the team for the first time to measure the temperature of the rings: a cool 77 Kelvin, or 77 degrees above absolute zero — the boiling temperature of liquid nitrogen and equivalent to 320 degrees below zero Fahrenheit.
The observations also confirm that Uranus’s brightest and densest ring, called the epsilon ring, differs from the other known ring systems within our solar system, in particular the spectacularly beautiful rings of Saturn.
“Saturn’s mainly icy rings are broad, bright and have a range of particle sizes, from micron-sized dust in the innermost D ring, to tens of meters in size in the main rings,” said Imke de Pater, a UC Berkeley professor of astronomy. “The small end is missing in the main rings of Uranus; the brightest ring, epsilon, is composed of golf ball-sized and larger rocks.” [emphasis mine]
The mystery is why this ring has no dust, something not seen with any other ring system in the solar system, including the inner rings of Uranus itself..
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New radio images taken by the ground-based telescopes by the ALMA and VLT telescopes in Chile have allowed scientists to better determine the make-up and temperature of the rings of Uranus.
The image above is from their paper. From the caption:
Images of the Uranian ring system at 3.1 mm (ALMA Band 3; 97.5 GHz), 2.1 mm (ALMA Band 4; 144 GHz), 1.3 mm (ALMA Band 6; 233 GHz), and 18.7 μm (VLT VISIR; 100 THz)…The planet itself is masked since it is very bright compared to the rings.
From the article above:
The new images taken by the Atacama Large Millimeter/submillimeter Array (ALMA) and the Very Large Telescope (VLT) allowed the team for the first time to measure the temperature of the rings: a cool 77 Kelvin, or 77 degrees above absolute zero — the boiling temperature of liquid nitrogen and equivalent to 320 degrees below zero Fahrenheit.
The observations also confirm that Uranus’s brightest and densest ring, called the epsilon ring, differs from the other known ring systems within our solar system, in particular the spectacularly beautiful rings of Saturn.
“Saturn’s mainly icy rings are broad, bright and have a range of particle sizes, from micron-sized dust in the innermost D ring, to tens of meters in size in the main rings,” said Imke de Pater, a UC Berkeley professor of astronomy. “The small end is missing in the main rings of Uranus; the brightest ring, epsilon, is composed of golf ball-sized and larger rocks.” [emphasis mine]
The mystery is why this ring has no dust, something not seen with any other ring system in the solar system, including the inner rings of Uranus itself..
I must unfortunately ask you for your financial support because I do not depend on ads and rely entirely on the generosity of readers to keep Behind the Black running. You can either make a one time donation for whatever amount you wish, or you sign up for a monthly subscription ranging from $2 to $15 through Paypal or $3 to $50 through Patreon.
Your support will allow me to continue covering science and culture as I have for the past twenty years, independent and free from any outside influence.
Your support is even more essential to me because I not only keep this site free from advertisements, I do not use the corrupt social media companies like Google, Twitter, and Facebook to promote my work. I depend wholly on the direct support of my readers.
You can provide that support to Behind The Black with a contribution via Patreon or PayPal. To use Patreon, go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation. For PayPal click one of the following buttons:
If Patreon or Paypal don't work for you, you can support Behind The Black directly by sending your donation by check, payable to Robert Zimmerman, to
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652
Or you can donate by using Zelle through your bank. You will need to give my name and email address (found at the bottom of the "About" page). The best part of this electronic option is that no fees will be deducted! What you donate will be what I receive.
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