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Cassini-Huygens Reaches Phoebe
Anonymous Explorer writes "The Cassini-Huygens
probe is set to fly by the largest outer Saturn moon of Phoebe today. Cassini will be roughly 2000 km from the surface of Phoebe at 1:56 Pacific time Friday, June 11. Thats
pretty darn close. The newest
images of Phoebe are already thousands of times better than the previous ones taken by the Voyager
2 mission in 1981. Phoebe is interesting in that it maintains a retrograde orbit around Saturn. This has lead to the hypothesis that it is an ancient asteroid that has been captured by the gravitational pull from Saturn. Phoebe may provide some important insights into the composition of early building blocks of our planets. Phoebe was discovered in 1898 by American astronomer William
Pickering. As always, discussion about this mission can be found at
#cassini on irc.freenode.net."
Here are some links about phoebe and the Cassini-Huygens:
Phoebe
Cassini-Huygens
That is actually Phoebe on both sides. The right one is a picture of Phoebe 13 hours after the left one. it takes Phoebe only 9 and a half hours to make a full spin on it's axis (It has 9 and a half hour days). Those are two different hemispheres.
I'm really excited about the new photos... I hope they release full res mosaics and don't delay... pre-processed surface texture and heightmap data would be nice, too.
:)
If you want to get an idea of just how high res pictures they're going to get, do the following:
1) Download the program "Celestia". Build and run it.
2) While it is building, pull up the last picture that Cassini took of Phoebe.
3) When Celestia comes up, full screen it.
4) Go into the configuration and tell it to include full details. Exit the configuration menu.
5) Press enter, and type in "Phoebe". Press enter.
6) Press 'g' to go to Phoebe (note: Phoebe is currently false-texture in Celestia, since we don't know much about it)
7) Middle click and hold down, and drag the mouse until you're at a distance of 658,000 kilometers.
8) Press ctrl-'+' to zoom, until the resolution of Phoebe that you're seing on the screen is about the same as that in the NASA picture (note: resolution, not size. The nasa picture is enlarged).
9) Without changing the zoom, hold middle click againa nd drag the mouse until the distance is 2,000 kilometers.
10) Hold down shift, and use the arrow keys to look around. That's the sort of resolution images that they should be able to get.
Impressive, isn't it? I can't wait!
Carbon, made, only wants to be unmade.
The newest images of Phoebe are already thousands of times better than the previous ones taken by the Voyager 2 mission in 1981.
No, but it is hoped they will be. At best, the newest released images are 10x better than Voyager. Expect the high res images later today. You are getting ahead of yourself.
an ill wind that blows no good
It has a retrograde orbit
Nothing in the world is more dangerous than sincere ignorance and conscientious stupidity.
Not only that, it's a really eccentric, far-flung orbit. It's marginally more interesting than the "normal" satellites of Saturn, at least based on what we know about them, which is admittedly not much.
Phoebe is really far from Saturn. Also, there may be some gravitational slingshotting in the course (not sure how severe, since Phoebe's mass is small) so the path to saturn may not be a straight line in the geometric sense.
Phoebe is actually believed to be a captured Kuiper Belt object (KBO). This means its composition might be very icy/organic, making it more like a non-active comet than an asteroid.
"I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
-5 for most of the year.
As a captured Kuiper Belt object, it may consist of relatively unaltered material from the birth of the solar system. The ring material, on the other hand, is constantly altering itself due to incessant collisions.
"I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
check the facts yourself!
There is no DSN tracking pass today, so the high res images won't even be in JPL's hot little hands until tomorrow afternoon.
--Rob
It isn't. It's just more accessable.
Actually it is.
It's interesting because it only reflects 6% of the suns light received. According to the article I linked, the darkness could be attributed to carbon and scientists are fairly certain that frozen water is there -- two of the main ingredients for life as we know it, not that they are expecting to find any life there.
Not everything is analogous to cars. Car analogies rarely work.
20:56 UTC is Earth Recieve Time.. It actually happened at 19:34 UTC Spaceraft event time... we really at 19:35 ephemeris time.
There are 10 types of people in this world, those who can count in binary and those who can't.
it's at 13:56 PDT ERT ... where ERT means Earth Receive Time.
It's at 20:56 UTC ERT, the SCET (Spacecraft Event Time) was at 19:34 UTC.
See this link for an explination of the time conventions: http://www2.jpl.nasa.gov/basics/bsf2-3.html
Actually UTC is damn awful time system because of leap seconds which cannot be predicted. All calculations must use ET (Ephemeris Time) which is almost always SCET. The 'REAL' flyby occured around 19:35 ET, the exact time to be determined from tracking after the flyby.
There are 10 types of people in this world, those who can count in binary and those who can't.
Pictures start coming down to the ground tomorrow morning and are dowloaded all day. Right now Cassini is busy taking pictures so it can't point it's antenna at Earth. And the pictures will take all day to download because even though they are using an antenna as tall as a 25 story building, so still can't get a very high data rate transmitting at 80 W from 10AU.
After that they will take some time to process, but when they are released they will either be at www.ciclops.org or saturn.jpl.nasa.gov.
There are 10 types of people in this world, those who can count in binary and those who can't.
"Cassini-Huygens"
:)
Just out of interest, how is the second word pronounced ?...
Roughly: Hoy-ginz. We got a pair of servers in a few months ago, named them Cassini and Huygens. First thing we had to do was look that up exactly that.