TEGA - Round 2 |
TEGA - Round 2 |
Jul 19 2008, 12:04 PM
Post
#1
|
|
Founder Group: Chairman Posts: 14433 Joined: 8-February 04 Member No.: 1 |
I challenge you not to look at this and make a ping/spring/boing happy sort of a noise.
http://phoenix.lpl.arizona.edu/images/gallery/lg_14223.jpg |
|
|
Jul 22 2008, 08:48 AM
Post
#16
|
|
Junior Member Group: Members Posts: 36 Joined: 28-May 08 Member No.: 4152 |
It looks like they've successfully uttered the command "Open Sesame". Previously, they'd been asking HAL to open the pod-bay doors - with predictably little success... (Could this suggest that this whole side of doors may be operational? If so, second hooray!) |
|
|
Jul 23 2008, 10:58 AM
Post
#17
|
|
Newbie Group: Members Posts: 6 Joined: 26-May 08 From: Melbourne, Australia Member No.: 4134 |
(Could this suggest that this whole side of doors may be operational? If so, second hooray!) IIRC, I believe the ovens on the ends were expected to be more likely to open fully because of the way the hinge mechanisms work. If that's true then it's more likely to suggest the other three end ovens will open too. |
|
|
Jul 23 2008, 03:07 PM
Post
#18
|
|
Senior Member Group: Members Posts: 2173 Joined: 28-December 04 From: Florida, USA Member No.: 132 |
...it's more likely to suggest the other three end ovens will open too. You mean the other two. The first oven opened was an end oven and one of its doors only partially opened, so it looks like we won't know exactly how each door will open until it's opened. |
|
|
Jul 23 2008, 05:07 PM
Post
#19
|
|
Member Group: Members Posts: 530 Joined: 21-March 06 From: Canada Member No.: 721 |
My momma always said, "TEGA is like a box of chocolates. You never know what you're gonna get."
|
|
|
Jul 23 2008, 06:07 PM
Post
#20
|
|
Junior Member Group: Members Posts: 57 Joined: 6-September 07 From: Netherlands Member No.: 3683 |
My momma always said, "TEGA is like a box of chocolates. You never know what you're gonna get." Now lets hope she finds some shrimp Could this whole side be opening fully instead of 'only' doors 0 and 3? They think they know which part is the problem but why could that part on this side of TEGA not be manufactured according to specs? I surely hope doors 1 and 2 work as well. Until we try there is no way of knowing. I guess they are first using the end ovens and perhaps try the other onces after that anyway. -------------------- Error: Life.sys corrupted
( R )eflect, ( R )epend, or ( R )eboot? |
|
|
Jul 23 2008, 09:25 PM
Post
#21
|
|
Member Group: Members Posts: 524 Joined: 24-November 04 From: Heraklion, GR. Member No.: 112 |
|
|
|
Jul 25 2008, 08:13 AM
Post
#22
|
|
Junior Member Group: Members Posts: 57 Joined: 6-September 07 From: Netherlands Member No.: 3683 |
Wow, thanks to Emily's Blog we now know more.
The part "not manufactured to a precise enough specification" is the "rail at the bottom". It tends to binds some doors while allowing others to open fine. While that sounds a bit sketchy to me it fuelers my hope that the other side of TEGA will be fine. More from her blog: QUOTE Finally, Leslie cleared up something I've apparently been confused about for a while. The reason they're pressing toward getting an ice-rich sample for TEGA is because of concern about a possible short. This short is a "high-side" short that could affect the whole instrument. It is not the same as the short that affected oven 4; that one is "cleared," it can't possibly affect the operation of TEGA in the future. So now we know this is another short. Not good news to hear, but on the positive side according to what Leslie Tamppari told Emily the team looking for a possible sol 60 rasp & deliver. The long wait is finally over, we just have to sit out this weekend. Thanks Emily for that update! -------------------- Error: Life.sys corrupted
( R )eflect, ( R )epend, or ( R )eboot? |
|
|
Jul 25 2008, 02:24 PM
Post
#23
|
|
Martian Photographer Group: Members Posts: 352 Joined: 3-March 05 Member No.: 183 |
So now we know this is another short. No. We don't. What Emily reported is what has been discussed previously--the team is worried about a "possible" future short that could threaten all ovens. There is something unknown that caused one short (in TA 4). There are types of shorts that are local to the oven, like that one. As Emily said, there are high side shorts that affect the entire instrument. There is "no way to assess the probability of another short circuit" occurring, so prudence dictates knocking off the highest priority samples first (http://phoenix.lpl.arizona.edu/07_02_pr.php). Once there is another short, it may simply be too late to be prudent. |
|
|
Jul 25 2008, 06:17 PM
Post
#24
|
|
Junior Member Group: Members Posts: 57 Joined: 6-September 07 From: Netherlands Member No.: 3683 |
No. We don't. What Emily reported is what has been discussed previously--the team is worried about a "possible" future short that could threaten all ovens. Misread that. I thought 'possible' meant they were note sure there is one as opposed to some new short occurring. -------------------- Error: Life.sys corrupted
( R )eflect, ( R )epend, or ( R )eboot? |
|
|
Jul 25 2008, 06:31 PM
Post
#25
|
|
Member Group: Members Posts: 191 Joined: 20-November 06 From: Saint Louis Member No.: 1376 |
This does not clear up anything for me. Then again, I did not personally design nor do I operate the instrument so nothing is likely to make sense to me. Just so long as the teams proceed cautiously, which they are, and do their absolute best to get some ice into that oven.
Have to admit though, those open doors sure were a beautiful sight. -------------------- - Matt
|
|
|
Jul 25 2008, 11:42 PM
Post
#26
|
|
Member Group: Members Posts: 470 Joined: 24-March 04 From: Finland Member No.: 63 |
Looks like they are finally going for it:
QUOTE Scientists and engineers on the mission Friday prepared plans to send Phoenix later in the day that would command the robotic arm to rasp the hard soil in the trench informally named "Snow White," collect the shavings and deliver them to an oven for analysis. It would be interesting to know more about the plan. Will the oven close immediately when its sensors confirm enough material has entered? If not, how will sublimation be avoided? -------------------- Antti Kuosmanen
|
|
|
Jul 26 2008, 01:33 AM
Post
#27
|
|
Junior Member Group: Members Posts: 39 Joined: 26-May 08 From: Ottawa, Canada Member No.: 4139 |
"NASA has tentatively scheduled a "mid-course" status report on the Phoenix mission July 31, when results of the latest TEGA run may be announced and new images released. The Phoenix team has asked for an extension of the nominal 92-sol (92 Earth-day) mission, and the outcome of that request may be revealed as well."
more: http://www.aviationweek.com/aw/generic/sto...EXCITE07258.xml |
|
|
Jul 26 2008, 03:15 AM
Post
#28
|
|
Member Group: Members Posts: 144 Joined: 17-July 07 From: Canberra Australia Member No.: 2865 |
I have always been a little in awe of the expertise of the MER and Phoenix teams in trouble shooting and fault rectification at such a huge distance. But for Phoenix, to my mind they have lost the high ground with respect to design and QA and should be indulging in some navel gazing.
First the rail not manufactured to specification jeopardising a proportion of the TEGA capability. OK stuff happens and QA tests get missed, but surely not with an interplanetary lander. Secondly, a short for oven 4 that is now '"cleared," it can't possibly affect the operation of TEGA in the future'. The cynic in me equates that to a fuse blowing. It can only happen once. But what was the inherent vulnerability that caused it in the first place? And now a revelation that they have assessed the possibility of another short related failure mode that could have the effect of taking out the entire capability. Possibly the same cause and effect as the oven 4 short. We can only hope the probability of occurrence is low and the ice sample will be successfully tested. Compliments to the team for identifying the possible failure mode. But that does beg the question as to why this wasn't identified before the mission. Easy to be wise in retrospect, but there does seem to have been a breakdown in their processes. |
|
|
Jul 26 2008, 03:46 PM
Post
#29
|
|
Member Group: Members Posts: 101 Joined: 29-January 06 Member No.: 667 |
Sol 60 Raw Images
This looks like post-delivery, 0749 local time. There's a little soil on the adjacent TEGA door. |
|
|
Jul 26 2008, 04:05 PM
Post
#30
|
|
Senior Member Group: Members Posts: 4251 Joined: 17-January 05 Member No.: 152 |
They certainly got some serious rasping done:
http://phoenix.lpl.arizona.edu/images/gallery/lg_16036.jpg |
|
|
Lo-Fi Version | Time is now: 5th June 2024 - 04:26 AM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE 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. |