IPB

Welcome Guest ( Log In | Register )

3 Pages V  < 1 2 3 >  
Reply to this topicStart new topic
A New Horizons Clone To 2003 Ub313?
Jyril
post Dec 22 2005, 06:42 PM
Post #16


Member
***

Group: Members
Posts: 249
Joined: 11-June 05
From: Finland (62°14′N 25°44′E)
Member No.: 408



QUOTE (SFJCody @ Dec 22 2005, 09:04 PM)
If 2003 UB313 has an albedo of ~70% (which seems to be the case given the difficulty in seeing it with Spitzer), it will have a surface slightly *brighter* than Proteus, even at 100AU.


At first try, Spitzer didn't detect 2003 UB313 because of a pointing error. Later observations haven't been published yet. But as the object is expected to have a Pluto-like or brighter surface, an albedo of 70% sounds reasonable.


--------------------
The universe is not only stranger than we imagine, it is stranger than we can imagine.
Go to the top of the page
 
+Quote Post
tasp
post Dec 22 2005, 06:47 PM
Post #17


Member
***

Group: Members
Posts: 903
Joined: 30-January 05
Member No.: 162



QUOTE (ugordan @ Dec 22 2005, 10:14 AM)
Yeah, but sending the probe sharply above or below the ecliptic plane inherently diminishes the Jovian gravity assist, does it not? I'd think the biggest speed gain is when your outbound velocity is directed along Jupiter's orbital velocity, not upwards or below. That means the greates speeds achievable using gravity assists will be more or less in the ecliptic plane.
I guess...  unsure.gif
*


Not sure I've worked this out in my head correctly, but at a 45 degree angle to Jupiter equator, maximum grav assist would be around 71% of nominal.

And the angle allows a closer approach per a given radiation exposure. Angled to reach Pluto, (17 degree maximum) the grav assist would be almost maximum possible if timed properly.

Once a craft is on the trajectory to Jupiter, mass of the craft becomes irrelevant in regards to grav assist, btw.

Dramatic photo op!
Go to the top of the page
 
+Quote Post
ugordan
post Dec 22 2005, 07:02 PM
Post #18


Senior Member
****

Group: Members
Posts: 3648
Joined: 1-October 05
From: Croatia
Member No.: 523



QUOTE (tasp @ Dec 22 2005, 07:47 PM)
Not sure I've worked this out in my head correctly, but at a 45 degree angle to Jupiter equator, maximum grav assist would be around 71% of nominal.

Isn't Jupiter's equator more or less edge on to the ecliptic? A 45 degree approach is bound to slinghot you way above/below the ecliptic.

QUOTE (tasp @ Dec 22 2005, 07:47 PM)
Once a craft is on the trajectory to Jupiter, mass of the craft becomes irrelevant in regards to grav assist, btw.

True, but the additional mass certainly counts when you're injecting the spacecraft to Jupiter in the first place. The fact Jupiter doesn't care how massive you are doesn't help your escape from an Earth parking orbit at all.


--------------------
Go to the top of the page
 
+Quote Post
SFJCody
post Dec 22 2005, 07:33 PM
Post #19


Member
***

Group: Members
Posts: 813
Joined: 8-February 04
From: Arabia Terra
Member No.: 12



QUOTE (tasp @ Dec 22 2005, 06:47 PM)
Not sure I've worked this out in my head correctly, but at a 45 degree angle to Jupiter equator, maximum grav assist would be around 71% of nominal.

*


Why 45 degrees (except as a 'worst case')? 2003 UB313 isn't all that far from the ecliptic, and it's getting closer (it should pass through it before this century is out).

Edit: A thought about data transfer: At 100AU, the New Horizons clone would take years to downlink a 'Pluto encounter's worth' of data. A larger high-gain or optical communication may be needed.
Go to the top of the page
 
+Quote Post
SFJCody
post Dec 23 2005, 11:28 AM
Post #20


Member
***

Group: Members
Posts: 813
Joined: 8-February 04
From: Arabia Terra
Member No.: 12



This is beginning to resemble the TAU (thousand astronomical unit) mission conceived in the mid 80s.


Bulletin of the American Astronomical Society, Vol. 18, p.1012 (09/1986)


Edit: Scientifically, a mission to 2003 UB313 (or 2005 FY9, which might be more Pluto-like) would be a useful counterpart to New Horizons. New Horizons will pass Pluto a few decades past perihelion, complete with atmosphere/outgassing/geysers/etc. But unless we are still around in a century's time we won't get to see it in its more quiescent aphelion state. Luckily, Pluto's cousin TNOs are close to aphelion (which is probably why they escaped detection for so long).
Attached Image
Go to the top of the page
 
+Quote Post
Guest_BruceMoomaw_*
post Dec 24 2005, 01:45 AM
Post #21





Guests






This seems to be the type of mission that can ONLY be done either by a solar sail or by nuclear-electric propulsion. (I know which one I'd prefer.)

http://trs-new.jpl.nasa.gov/dspace/bitstre...9/1/99-0394.pdf
http://trs-new.jpl.nasa.gov/dspace/bitstre...7/1/99-1367.pdf
http://trs-new.jpl.nasa.gov/dspace/bitstre...9/1/99-1857.pdf
http://trs-new.jpl.nasa.gov/dspace/bitstre...4/1/01-0122.pdf
http://trs-new.jpl.nasa.gov/dspace/bitstre...0/1/00-1293.pdf
http://trs-new.jpl.nasa.gov/dspace/bitstre...4/1/00-0010.pdf
Go to the top of the page
 
+Quote Post
Comga
post Dec 24 2005, 06:09 AM
Post #22


Junior Member
**

Group: Members
Posts: 87
Joined: 19-June 05
Member No.: 415



QUOTE (SFJCody @ Dec 23 2005, 05:28 AM)
This is beginning to resemble the TAU (thousand astronomical unit) mission conceived in the mid 80s.
*


Wow. Thanks for dredging up the TAU document. What a blast from the past! It is hard to think how ideas so far out were being discussed in those days. This topic is about as close as we come these days.
Go to the top of the page
 
+Quote Post
edstrick
post Dec 24 2005, 10:02 AM
Post #23


Senior Member
****

Group: Members
Posts: 1870
Joined: 20-February 05
Member No.: 174



The "Purple Pigeons of Planetology" Wish List. Don't remember them all, but things like Rosetta and Cassini are in that category.
Go to the top of the page
 
+Quote Post
ilbasso
post Dec 24 2005, 10:44 PM
Post #24


Member
***

Group: Members
Posts: 753
Joined: 23-October 04
From: Greensboro, NC USA
Member No.: 103



At what angle and distance did Ulysses encounter Jupiter to be shot into an 80-dgree inclided orbit?


--------------------
Jonathan Ward
Manning the LCC at http://www.apollolaunchcontrol.com
Go to the top of the page
 
+Quote Post
Planet X
post Jan 9 2006, 11:59 AM
Post #25


Junior Member
**

Group: Members
Posts: 34
Joined: 9-January 06
Member No.: 639



I was looking at the planetary orbits (as viewed from 90 degrees above the ecliptic) the other day and noticed it might be possible to fly a Uranus-2003 UB313 mission. Just wondering, is the NH2 concept dead? If not, would it be possible to fly that mission to Uranus and 2003 UB313? That, IMO, would be one cool mission. Has anyone yet pondered this idea? Later!

J P
Go to the top of the page
 
+Quote Post
abalone
post Jan 9 2006, 01:54 PM
Post #26


Member
***

Group: Members
Posts: 362
Joined: 12-June 05
From: Kiama, Australia
Member No.: 409



QUOTE (ugordan @ Dec 23 2005, 06:02 AM)
Isn't Jupiter's equator more or less edge on to the ecliptic?
*

It is not Jupiter's equator or the ecliptic that matter it is the plane of the planets orbit. It just so happens that for Jupiter they are almost the same. For Uranus it matters of course if it is to be used for grav assist

QUOTE
Planet X Posted Yesterday, 10:59 PM
At what angle and distance did Ulysses encounter Jupiter to be shot into an 80-dgree inclided orbit?


If a gravity assist is an increase in velocity then this may not qualify as if was simply using Jupiter to change the inclination of the orbit, but then again that is a deltaV so it may. unsure.gif unsure.gif unsure.gif
Go to the top of the page
 
+Quote Post
ugordan
post Jan 9 2006, 02:09 PM
Post #27


Senior Member
****

Group: Members
Posts: 3648
Joined: 1-October 05
From: Croatia
Member No.: 523



QUOTE (abalone @ Jan 9 2006, 02:54 PM)
It is not Jupiter's equator or the ecliptic that matter it is the plane of the planets orbit. It just so happens that for Jupiter they are almost the same. For Uranus it matters of course if it is to be used for grav assist
*

I think you misunderstood me. What I was getting at is that most planets (well, all when you exclude Pluto tongue.gif) orbit in practically the same plane. Jupiter's equatorial plane is also similar to that plane meaning the most intense radiation area around Jupiter is "conveniently" placed so most spacecraft that want to reach one of those planets need to fly through the densest part of the radiation belt IF they want to maximize the slingshot effectiveness, that is fly as close to Jupiter as possible.


--------------------
Go to the top of the page
 
+Quote Post
abalone
post Jan 9 2006, 02:29 PM
Post #28


Member
***

Group: Members
Posts: 362
Joined: 12-June 05
From: Kiama, Australia
Member No.: 409



QUOTE (ugordan @ Jan 10 2006, 01:09 AM)
I think you misunderstood me. What I was getting at is that most planets (well, all when you exclude Pluto tongue.gif) orbit in practically the same plane. Jupiter's equatorial plane is also similar to that plane meaning the most intense radiation area around Jupiter is "conveniently" placed so most spacecraft that want to reach one of those planets need to fly through the densest part of the radiation belt IF they want to maximize the slingshot effectiveness, that is fly as close to Jupiter as possible.
*

Got it, thanks
Go to the top of the page
 
+Quote Post
Bob Shaw
post Jan 9 2006, 09:48 PM
Post #29


Senior Member
****

Group: Members
Posts: 2488
Joined: 17-April 05
From: Glasgow, Scotland, UK
Member No.: 239



QUOTE (SFJCody @ Dec 22 2005, 08:33 PM)
Why 45 degrees (except as a 'worst case')? 2003 UB313 isn't all that far from the ecliptic, and it's getting closer (it should pass through it before this century is out).

Edit: A thought about data transfer: At 100AU, the New Horizons clone would take years to downlink a 'Pluto encounter's worth' of data. A larger high-gain or optical communication may be needed.
*



I think it was Bruce Moomaw who commented on a related issue, ie the cost per unit of data, and suggested that future spacecraft needed to be examined on an accounting basis as well as in terms of pure science (I wonder how the ISS would come out? NOT!). It does make you think, though, that with spacecraft longevity almost a given, s-l-l-l-o-o-o-w data return might have a range of benefits. Smaller spacecraft sizes, more robust components, and cheaper radio facilities on Earth all spring to mind. Does it *really* matter if the results of a wham-bang-thankyou-ma'am encounter take years to be returned?

Bob Shaw


--------------------
Remember: Time Flies like the wind - but Fruit Flies like bananas!
Go to the top of the page
 
+Quote Post
helvick
post Jan 9 2006, 10:18 PM
Post #30


Dublin Correspondent
****

Group: Admin
Posts: 1799
Joined: 28-March 05
From: Celbridge, Ireland
Member No.: 220



QUOTE (Bob Shaw @ Jan 9 2006, 10:48 PM)
Smaller spacecraft sizes, more robust components, and cheaper radio facilities on Earth all spring to mind. Does it *really* matter if the results of a wham-bang-thankyou-ma'am encounter take years to be returned?
*

We're going to need an orbiting deep space receiver to handle all this inbound data fairly soon. The Earth\Moon L4\L5 points seem like a good spot. Are there any plans?
Go to the top of the page
 
+Quote Post

3 Pages V  < 1 2 3 >
Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 19th March 2024 - 08:01 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 funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member.