IPB

Welcome Guest ( Log In | Register )

2 Pages V   1 2 >  
Reply to this topicStart new topic
Future Stardust Missions?, What's She Gonna Do Now?
John M. Dollan
post Jan 31 2006, 07:50 PM
Post #1


Junior Member
**

Group: Members
Posts: 21
Joined: 31-January 05
From: Havre, MT
Member No.: 163



Hi folks...

I read today that Stardust has been placed in hibernation, while in an orbit that reaches out substantially further than Mars. No mention was made regarding future plans.

I was curious... since the Dawn mission has been put on hold, is it possible that Stardust will be used to explore any bodies in the Belt?

...John...


--------------------
"To make an apple pie from scratch, you must first create the universe..."
-- Carl Sagan
Go to the top of the page
 
+Quote Post
Guest_AlexBlackwell_*
post Jan 31 2006, 07:54 PM
Post #2





Guests






QUOTE (John M. Dollan @ Jan 31 2006, 07:50 PM)
Hi folks...

I read today that Stardust has been placed in hibernation, while in an orbit that reaches out substantially further than Mars.  No mention was made regarding future plans.

I was curious... since the Dawn mission has been put on hold, is it possible that Stardust will be used to explore any bodies in the Belt?

Note that potential proposers for the Discovery 2006 and Missions of Opportunity AO are being offered the option to propose uses for both Stardust and Deep Impact.
Go to the top of the page
 
+Quote Post
John M. Dollan
post Jan 31 2006, 08:09 PM
Post #3


Junior Member
**

Group: Members
Posts: 21
Joined: 31-January 05
From: Havre, MT
Member No.: 163



Thanks much for the information!

...John...


--------------------
"To make an apple pie from scratch, you must first create the universe..."
-- Carl Sagan
Go to the top of the page
 
+Quote Post
Guest_BruceMoomaw_*
post Jan 31 2006, 09:57 PM
Post #4





Guests






I'm rather skeptical about an extended mission for Stardust. First, unless they can find another comet for it to fly by (as opposed to near-Earth asteroids), the only usable science instrument it has is a black and white camera. Second, it's much lower on remaining delta-V than Deep Impact is.
Go to the top of the page
 
+Quote Post
djellison
post Jan 31 2006, 10:22 PM
Post #5


Administrator
****

Group: Chairman
Posts: 13806
Joined: 8-February 04
Member No.: 1



The Stardust people seemed quite bold and confident when suggesting such a follow on. I agree - DI is more likely to get an extension that Stardust, but given it's shielding, Stardust could be sent on a fairly do-or-die flyby of another nucleus in a few years. No reason why they can't just hibernate the thing as they have now for 4, 5 years, and wake it up in the way they did for Giotto for another flyby. Even just an imaging sequence would be another set of images of a small body.

Doug
Go to the top of the page
 
+Quote Post
tedstryk
post Feb 1 2006, 12:29 AM
Post #6


Interplanetary Dumpster Diver
****

Group: Moderator
Posts: 4241
Joined: 17-February 04
From: Powell, TN
Member No.: 33



QUOTE (BruceMoomaw @ Jan 31 2006, 09:57 PM)
I'm rather skeptical about an extended mission for Stardust.  First, unless they can find another comet for it to fly by (as opposed to near-Earth asteroids), the only usable science instrument it has is a black and white camera.  Second, it's much lower on remaining delta-V than Deep Impact is.
*


As for instruments, that is simply not true. First, it has the Cometary and Interstellar Dust Analyzer (CIDA), a mass spectrometer, and it also has the Dust Flux Monitor Instrument (DFMI). On top of that, it is only a black and white camera due to the stuck filter wheel. I remember reading that they thought they could likely free it, but didn't want to risk it later getting stuck on a less favorable filter during the main flyby. But at this point, they could risk it.


--------------------
Go to the top of the page
 
+Quote Post
Guest_BruceMoomaw_*
post Feb 1 2006, 07:23 AM
Post #7





Guests






Well, I specified "unless they can find another comet" -- in which case of course those other two instruments do become relevant. It's if they fly it by an asteroid (a lot easier to do, given the number of them) that only the camera would be of any use.
Go to the top of the page
 
+Quote Post
tedstryk
post Feb 1 2006, 05:15 PM
Post #8


Interplanetary Dumpster Diver
****

Group: Moderator
Posts: 4241
Joined: 17-February 04
From: Powell, TN
Member No.: 33



QUOTE (BruceMoomaw @ Feb 1 2006, 07:23 AM)
Well, I specified "unless they can find another comet" -- in which case of course those other two instruments do become relevant.  It's if they fly it by an asteroid (a lot easier to do, given the number of them) that only the camera would be of any use.
*


Oops..missed that part rolleyes.gif


--------------------
Go to the top of the page
 
+Quote Post
Guest_AlexBlackwell_*
post Feb 1 2006, 05:24 PM
Post #9





Guests






QUOTE (BruceMoomaw @ Feb 1 2006, 07:23 AM)
Well, I specified "unless they can find another comet" -- in which case of course those other two instruments do become relevant.  It's if they fly it by an asteroid (a lot easier to do, given the number of them) that only the camera would be of any use.

I would only add that the radio system could be used during a flyby (e.g., for mass determination and/or occultation science).
Go to the top of the page
 
+Quote Post
ugordan
post Feb 1 2006, 07:32 PM
Post #10


Senior Member
****

Group: Members
Posts: 3569
Joined: 1-October 05
From: Croatia
Member No.: 523



QUOTE (AlexBlackwell @ Feb 1 2006, 06:24 PM)
I would only add that the radio system could be used during an flyby (e.g., for mass determination and/or occultation science).
*

That would only work if the spacecraft was reaction wheel stabilized.
Does Stardust use reaction wheels or regular attitude thrusters?


--------------------
Go to the top of the page
 
+Quote Post
Guest_AlexBlackwell_*
post Feb 1 2006, 07:38 PM
Post #11





Guests






QUOTE (ugordan @ Feb 1 2006, 07:32 PM)
That would only work if the spacecraft was reaction wheel stabilized.

Huh?? 3 axis-stabilized (and spin-stabilized) spacecraft have long carried out radio science experiments. Have you ever heard of, say, Voyager?
Go to the top of the page
 
+Quote Post
ugordan
post Feb 1 2006, 07:45 PM
Post #12


Senior Member
****

Group: Members
Posts: 3569
Joined: 1-October 05
From: Croatia
Member No.: 523



QUOTE (AlexBlackwell @ Feb 1 2006, 08:38 PM)
Huh??  3 axis-stabilized (and spin-stabilized) spacecraft have long carried out radio science experiments.  Have you ever heard of, say, Voyager?
*

Yeah, but you're talking about radio occultations. Mass determination requires long periods of radio tracking WITHOUT any perturbations such as attitude thruster firings as they would trash the effect. Similar to the problem of measuring the Pioneer anomalous acceleration with the Voyagers - impossible.
Granted, I forgot about spin-stabilized craft, but Stardust isn't one such craft, is it?


--------------------
Go to the top of the page
 
+Quote Post
Guest_AlexBlackwell_*
post Feb 1 2006, 07:52 PM
Post #13





Guests






QUOTE (ugordan @ Feb 1 2006, 07:45 PM)
Yeah, but you're talking about radio occultations. Mass determination requires long periods of radio tracking WITHOUT any perturbations such as attitude thruster firings as they would trash the effect. Similar to the problem of measuring the Pioneer anomalous acceleration with the Voyagers - impossible.

I ain't talkin' about "the Pioneer anomalous acceleration"; I'm talking about standard flyby mass determinations which, by definition, are not "long periods." Are you aware that 3-axis and spin-stabilized spacecraft have routinely done this over the decades? For example, Galileo (Galileans), Viking (Phobos/Deimos), etc.
Go to the top of the page
 
+Quote Post
ugordan
post Feb 1 2006, 08:12 PM
Post #14


Senior Member
****

Group: Members
Posts: 3569
Joined: 1-October 05
From: Croatia
Member No.: 523



QUOTE (AlexBlackwell @ Feb 1 2006, 08:52 PM)
Are you aware that 3-axis and spin-stabilized spacecraft have routinely done this over the decades?  For example, Galileo (Galileans), Viking (Phobos/Deimos), etc.
*

I'm aware Galileo did mass determinations of either/both Gaspra and Ida, but it was spin stabilized craft. As for the Vikings, I'm not aware of the extent of their measurements, but a couple of hours of tracking data before and after the flyby might have probably done the trick.
However, any attitude maneuvers during the measurement will likely destroy any gravitational effect, especially if a small target body is concerned.
Another thing, determining a comet's mass might prove to be a bigger problem than that. Cometary particles impacting the S/C would also trash the the effect of the body's gravity.


--------------------
Go to the top of the page
 
+Quote Post
Guest_AlexBlackwell_*
post Feb 1 2006, 08:53 PM
Post #15





Guests






QUOTE (ugordan @ Feb 1 2006, 08:12 PM)
However, any attitude maneuvers during the measurement will likely destroy any gravitational effect, especially if a small target body is concerned.

Which is precisely why attitude maneuvers are not planned when acquiring gravity data, regardless of spacecraft type.
Go to the top of the page
 
+Quote Post

2 Pages V   1 2 >
Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 26th October 2014 - 03:40 AM
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 a project of the Planetary Society and is funded by donations from visitors and members. Help keep this forum up and running by contributing here.