Dawn Mission, pre-launch disscusion Options

[MarcF]

Really nice composite of the "Big-3".
I've never seen a resolved picture of Pallas before. It seems quite spherical (another dwarf planet ?)

Marc.

[Decepticon]

That Ceres image is beautiful!

[Greg Hullender]

Looking at those pictures of "the big 3" reminds me of this Wikipedia illustration showing the outlines of the first ten asteroids against the outline of the Moon:

http://en.wikipedia.org/wiki/Image:Moon_an...ids_1_to_10.svg

I remember being told that an extended mission to 2 Pallas was infeasible due to the difference in orbital inclinations, but I wonder if one to 10 Hygiea (the 4th-largest asteroid) has been discussed. Anyone know?

--Greg

[JRehling]

Looking at those pictures of "the big 3" reminds me of this Wikipedia illustration showing the outlines of the first ten asteroids against the outline of the Moon:

http://en.wikipedia.org/wiki/Image:Moon_an...ids_1_to_10.svg

I remember being told that an extended mission to 2 Pallas was infeasible due to the difference in orbital inclinations, but I wonder if one to 10 Hygiea (the 4th-largest asteroid) has been discussed. Anyone know?

--Greg

Hygiea is certainly much closer to the ecliptic (4 deg. inclination vs. 35 deg. for Pallas). However, it also lies farther from the Sun than Ceres, in an orbit that is particularly eccentric for a large asteroid, so unless there is the great chance that a trajectory would take Dawn to the near-perihelion node of Hygiea's orbit at the time that Hygiea happens to be there, this option would seem to be a delta-v "hog", too. It would also mean that a relatively quick flyby would be the payoff if such a trajectory were possible at all.

It would be nice to see up-close, but orbitally speaking, it's a tough target as asteroids go. I'm sure that any trajectory there would be in exchange for more than one flyby of easier targets.

[punkboi]

Launch update:

Date: Sept. 26 (No earlier than)
Launch Time: 7:24 a.m. EDT

At least the afternoon T-storms are obviously not an issue...

[elakdawalla]

What's the source of your information?

--Emily

[BPCooper]

They posted it about a week or so ago:

http://www.nasa.gov/missions/highlights/schedule.html

Window added today in fact.

[elakdawalla]

Thanks. Do you know why it's later than September 7?

--Emily

[BPCooper]

Well, an update: it could potentially move up.

The reason for the 26th is because there is another Delta 2 launch slated to launch out at Vandenberg on Sept. 18. PAO this afternoon here at KSC said if that mission is delayed, or launches on time, Dawn can move up. If delayed, Dawn could potentially be Sept. 19; if that Delta goes on the 18th, Dawn could be the 24th.

I guess we'll see.

[punkboi]

Now that it's September, here's hoping Dawn finally gets off the ground before the end of this month.

[BPCooper]

As a followup I was told recently that its chances of moving up are probably gone.

[punkboi]

Considering Dawn's luck over the past two years, I'm not surprised. Just launch it before Halloween, please. Just because.

[punkboi]

http://www.nasa.gov/centers/kennedy/launch...s-20070907.html

STATUS REPORT: ELV-090707


Expendable Launch Vehicle Status Report

Mission: Dawn
Location: Astrotech payload processing facility
Launch Vehicle: Delta II 7925-H
Launch Pad: 17-B
Launch Date: Sept. 26, 2007
Launch Window: 7:25 - 7:54 a.m. EDT

Engineers loaded liquid oxygen aboard the first stage late last week as a test for first stage components.

Dawn spacecraft operational readiness testing is complete.

Spacecraft thermal blanket closeout work is being finished today.

Technicians will be installing Dawn into the payload canister on Sept. 10 for transportation to Launch Complex 17. The spacecraft will be mated to the Delta II rocket at Pad 17-B on Sept. 11.

The flight program verification, an integrated launch readiness test with the Dawn spacecraft integrated with the Delta II, is scheduled for Sept. 13.

Installation of the payload fairing around the spacecraft is scheduled for Sept. 19.

***************************

Also, a new Dawn Journal is online: http://www.dawn-mission.org/mission/journal_9_03_07.asp

The journal was also posted on the Planetary Society weblog, but it's now been archived. Sorry Emily if I didn't link to that too

[volcanopele]

I don't know what all of you are talking about. I just picked up the latest issue of Astronomy magazine, and according to the October issue, Dawn launched on July 7.

I'm so confused! Did it launch or not??

Sorry, just thought it was funny. I can just see the headline in the December issue: NASA launches asteroid probe (for real this time)

[punkboi]

The Dawn journals are still better than the blogs on the Phoenix website... The Phoenix blogs are either too short and don't contain enough interesting information, the grammar is SO bad and the text sounds like something you'd read on an AOL chatroom, or the entries DON'T EVEN talk about the Phoenix mission itself. I'd post examples...but my Internet connection is too darn slow right now... I hate Verizon.

And I actually stopped looking at that Astronomy issue once I saw that article on Dawn "launching". A minor misspelling or one inaccurate tidbit is okay...but it's pretty unprofessional that the editor would let an entire article like that get through. It's all about reading "Sky & Telescope" for me, now!! J/k

EDIT: Where'd you go, Greg?? People will think I made that rant above for no apparent reason

By the way, the best space journals are the PI Perspectives on New Horizon by Alan Stern...and I'm not just saying that 'cause he actually posts on UMSF, lol.