Article: NASA Spacecraft Now Orbiting Huge Asteroid Vesta ... Hopefully

[July16th-20th]

Source: Space.com

NASA's Dawn spacecraft should now be circling the massive asteroid Vesta — if everything went according to plan.

Dawn was slated to slip into orbit around Vesta, the second-largest object in the main asteroid belt, at 10 p.m. PDT Friday (July 15; 1 a.m. EDT Saturday). So the probe has likely begun its yearlong orbital mission at the huge space rock, but scientists will have to wait a day or so to find out for sure.

Dawn has been thrusting with its ion engines for several days straight. The probe generally cannot communicate with mission controllers while it's thrusting, because its antenna is pointed away from Earth during these stretches.

But the spacecraft is due to re-orient and check in with the mission team at about 11:30 p.m. PDT Saturday (2:30 a.m. EDT Sunday), researchers said.



Read more: http://www.space.com/12306-dawn-vesta-asteroid-orbit-arrival.html

[krispos42]

1. So...

...nobody at NASA though to put the antenna on a set of gimbals?


Please tell me I'm missing something.

[daleo]

2. That would take extra mass

And its not mission critical. That's my guess.

[krispos42]

3. I understand not doing it for the probes that coast.

E.g., Voyager 2. They can turn any old way they need to and it doesn't matter.


But this one has an ion engine and thrusts continually, so it has to be pointed in a specific direction to navigate.

:shrug:

I would have though the dish would be on gimbals.

[blackbart99]

8. voyager is not orbiting anything....

Dawn is making moves to orbit vesta......thx daleo...your explanation is spot on....not mission critical. They can get all the data later when its in orbit.

[muriel_volestrangler]

9. The dish takes up most of one side

Making it so that it could rotate and point in significantly different directions would have been quite a redesign.

[krispos42]

14. It's boxier than I envisioned.

Of course, that's with the solar cells folded up.

But I see your point. Even if it was mounted on gimbals, in this picture it wouldn't be able to move more than a few degrees in any axis anyway. :-)


My mental image was of something with more booms on it...

[liberalmike27]

16. I doubt

if instant gratification was one of the mission goals.

[trud]

10. anything moving

much more susceptible to mechanical failure, is my guess.

[localroger]

11. Exactly

This was one of the big lessons drawn from Cassini, which also has a fixed dish and can't communicate during maneuvers and observations. The risk to the mission from failure of a moving part is much worse than the risk of a catastrophic failure during a communication blackout.

[July16th-20th]

13. You're missing something

Our budget has been shit for three (3) decades, despite the Grand Pronouncements of President after President.

[DavidDvorkin]

15. I'm sure they thought of it, and I'm sure that

there were good reasons for not doing it.

I worked at NASA during the Apollo years, and I can assure you that NASA types consider all the obvious details as well as vast numbers of details that are anything but obvious.

[July16th-20th]

17. Exactly right, brother.

We always think of everything. Not a joke. I'm serious.

[DavidDvorkin]

18. I do remember one time when I neglected to think of something

I drove to work, at MSC, in a van we had just bought. The let-this-guy-in sticker was on the windshield of our other car. I forgot all about it and tried to drive through the check point just like a regular employee.

Guns were almost drawn. It would have been much worse nowadays.

[joshcryer]

4. Weird that NASA TV isn't covering it...

[Kablooie]

5. It's controlled at JPL in La Canada.

I know the Chief Engineer but haven't talked to him for a few years.

[MilesColtrane]

6. Very sciencey, but....

wouldn't it be cheaper to just shoot Bruce Willis at Apophis when it swings around for a kill shot?

If he impacts with enough velocity it could keep that rock from bombing us back to the Cretaceous.

[RUMMYisFROSTED]

12. He could break it apart with soundwaves from his harmonica.

[MilesColtrane]

20. In space no one can hear you scream from bad blues harp.

[RUMMYisFROSTED]

25. Link?

[MilesColtrane]

26. !

:rofl:

[trud]

21. excuse me, no air, no sound waves. n/t

[RUMMYisFROSTED]

24. You're completely ignoring Willis' Law.

[BiggJawn]

7. "The probe generally cannot communicate with mission controllers while it's thrusting..."

Obviously, it's male...
Couldn't resist.

[Endangered Specie]

22. ah, you made a funny

[GreenPartyVoter]

19. How exciting! :^D

[Baclava]

23. Confirmed - in orbit

"Dawn will remain in orbit around Vesta for a year, before gently boosting away to begin the trip to Ceres, the second half of its asteroid belt adventure."



http://news.discovery.com/space/dawn-enters-asteroid-vesta-orbit-110716.html