IPB

Welcome Guest ( Log In | Register )

 
Reply to this topicStart new topic
Rotation Period Of Saturn, Cassini findings
MarcF
post Mar 26 2015, 08:46 PM
Post #1


Member
***

Group: Members
Posts: 241
Joined: 16-May 06
From: Geneva, Switzerland
Member No.: 773



A new result about Saturn's spin rate was published today:

http://news.sciencemag.org/space/2015/03/s...got-bit-shorter

"Helled's team deduced the spin from the planet's gravity field. Saturn spins fast, making its equator bulge outward, which distorts the gravity field in ways Cassini has measured. By modeling this effect, Helled's team reports online today in Nature that Saturn spins every 10 hours and 32 minutes and 45 seconds with an uncertainty of 46 seconds. That's more than 6 minutes faster than Voyager found."

"Because Saturn is so big, the equator at the level of the atmosphere must spin nearly 400 kilometers per hour faster than the Voyager value implied. Scientists measure wind speeds relative to the spinning planet, so the new rotation rate alters the estimated wind speeds by that same amount."

I would be curious to see the corrected wind profiles.
Regards,
Marc.
Go to the top of the page
 
+Quote Post
Explorer1
post Jan 21 2019, 04:49 PM
Post #2


Senior Member
****

Group: Members
Posts: 2073
Joined: 13-February 10
From: Ontario
Member No.: 5221



A little less than four years later, looks like a new (and hopefully final!) result: 10 hours, 33 minutes, 38 seconds

http://iopscience.iop.org/article/10.3847/...357/aaf798/meta

'Ring seismology' is not a term one hears every day! One mystery down, many more to go.

Press release: https://www.jpl.nasa.gov/news/news.php?feature=7316
Go to the top of the page
 
+Quote Post
Holder of the Tw...
post Jan 21 2019, 05:46 PM
Post #3


Member
***

Group: Members
Posts: 540
Joined: 17-November 05
From: Oklahoma
Member No.: 557



Well, down in the details in the abstract, they list their error bars as + 1 min 52 sec and - 1 min 19 sec.

This overlaps with the earlier result from 2015, which actually claims to be more precise.

These two results both agree that Saturn is spinning faster than the estimates from Voyager. Also other estimates from Cassini.
Go to the top of the page
 
+Quote Post
nprev
post Jan 21 2019, 07:45 PM
Post #4


Merciless Robot
****

Group: Admin
Posts: 8783
Joined: 8-December 05
From: Los Angeles
Member No.: 602



Topic title edited for clarity and scope. smile.gif


--------------------
A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
Go to the top of the page
 
+Quote Post

Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 28th March 2024 - 09:55 PM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member.