IPB

Welcome Guest ( Log In | Register )

9 Pages V  « < 3 4 5 6 7 > »   
Reply to this topicStart new topic
The Descent into Victoria, Possible and Actual Strategies
djellison
post Jun 29 2007, 12:19 PM
Post #61


Founder
****

Group: Chairman
Posts: 14431
Joined: 8-February 04
Member No.: 1



My intepretation is this
Attached thumbnail(s)
Attached Image
 
Go to the top of the page
 
+Quote Post
MarsIsImportant
post Jun 29 2007, 02:22 PM
Post #62


Member
***

Group: Members
Posts: 258
Joined: 22-December 06
Member No.: 1503



Green marks the entry path. That's my understanding too.
Go to the top of the page
 
+Quote Post
Tesheiner
post Jun 29 2007, 02:26 PM
Post #63


Senior Member
****

Group: Moderator
Posts: 4279
Joined: 19-April 05
From: .br at .es
Member No.: 253



So that's more or less the same site as of sol 952.
Go to the top of the page
 
+Quote Post
djellison
post Jun 29 2007, 02:29 PM
Post #64


Founder
****

Group: Chairman
Posts: 14431
Joined: 8-February 04
Member No.: 1



Just 'left' of it, if that makes any sense.
Go to the top of the page
 
+Quote Post
MarsIsImportant
post Jun 29 2007, 03:17 PM
Post #65


Member
***

Group: Members
Posts: 258
Joined: 22-December 06
Member No.: 1503



What I don't understand is that they picked an ingress spot further away from the current rover position than they had too. In fact, the spot they picked requires going over the lip of a dune. Again, that doesn't seem necessary if they had chosen this area marked in red.

Attached Image


Again, green arrow points the area of entry as understood through the conference yesterday.
Go to the top of the page
 
+Quote Post
djellison
post Jun 29 2007, 03:51 PM
Post #66


Founder
****

Group: Chairman
Posts: 14431
Joined: 8-February 04
Member No.: 1



Slope too steep there perhaps - too close to the cliff edge w.r.t. shadowing solar and comms.

Doug
Go to the top of the page
 
+Quote Post
MarsIsImportant
post Jun 29 2007, 04:10 PM
Post #67


Member
***

Group: Members
Posts: 258
Joined: 22-December 06
Member No.: 1503



Well, the slope is not too steep. As for being too close to the cliffs, that would only be true if they were going straight down. I think the reason might be simply because that a straight line is not necessarily the the fastest way to the target. If they went down the area I marked in red, then they would have to traverse the slope for much longer of a distance to get to the intended target. That means a very slow pace on the slope.

The way the MER team intend to go maybe longer in over all distance, but they will have only to go half the distance to the target on a slope. Much of the travel will be quick on flat surface. That is the only reasonable argument for ingress placement that I can think of. Plus, doing the toe dip in and out at that particular place might make it easier for rover to get out again through compression of the soil at that spot. I guess that I'm answering my own questions.
Go to the top of the page
 
+Quote Post
dvandorn
post Jun 29 2007, 05:14 PM
Post #68


Senior Member
****

Group: Members
Posts: 3419
Joined: 9-February 04
From: Minneapolis, MN, USA
Member No.: 15



I think you have the right idea, MII. I know that during the telecon yesterday, SS made several statements about how they were planning a very specific route that addresses rover safety above all. He said that they would *not* deviate from this route in order to go after interesting-looking targets, but that they may stop *along* this route to look at interesting targets of opportunity.

Whatever the rationale, this route has been selected to maximize the safety of the rover and to get it to the bright-band exposure that is the top scientific priority of entering the crater. Any deviation from this pre-selected route will come only from rover safety concerns, methinks...

-the other Doug


--------------------
“The trouble ain't that there is too many fools, but that the lightning ain't distributed right.” -Mark Twain
Go to the top of the page
 
+Quote Post
Tom Tamlyn
post Jun 29 2007, 06:21 PM
Post #69


Member
***

Group: Members
Posts: 443
Joined: 1-July 05
From: New York City
Member No.: 424



For those who missed the press conference, a telephone replay is available until July 2.

http://www.nasa.gov/home/hqnews/2007/jun/H...ria_Crater.html

Most of the information has been well summarized in this thread, but it's always a pleasure to admire how clearly SS speaks about rover operations and science, and how well he communicates the enthusiasm of the team. I can't think of anyone else in his league.

TTT
Go to the top of the page
 
+Quote Post
Tman
post Jun 29 2007, 07:24 PM
Post #70


Member
***

Group: Members
Posts: 877
Joined: 7-March 05
From: Switzerland
Member No.: 186



Surprisingly on the SPACE-MULTIMEDIA site, that usually has provided only manned spaceflight topic, is it now available - for good I guess. As well the last NASA audio teleconference for the Dawn mission. smile.gif


--------------------
Go to the top of the page
 
+Quote Post
BrianL
post Jun 30 2007, 03:55 PM
Post #71


Member
***

Group: Members
Posts: 530
Joined: 21-March 06
From: Canada
Member No.: 721



One thing is not clear to me in what was announced. Do they feel that the bright band is as deep as they can go into the crater to keep the rover safe? That would be very disappointing if they were not able to continue further downslope to get to older layers of exposed rock.

Brian
Go to the top of the page
 
+Quote Post
djellison
post Jun 30 2007, 04:13 PM
Post #72


Founder
****

Group: Chairman
Posts: 14431
Joined: 8-February 04
Member No.: 1



It's a case of 'see how we go'. The white band is the only target so far - they have no specific goals beyond that simply because they can't really tell what the terrain is like after that until they get closer to it.

It's probable that there may be a few tens of metres further exposed rock that is easily navigable beyond the white layer. However, if beyond that it's just sand, then they're not going to try 12 degree sand slopes, they're a death trap (see the trouble they had near Wopmay rock in Endurance - many sols of churning and wheels up to the hubs and beyond in sand)

It all depends on what the terrain offers when we get closer. If it's just a tiny bit of sand on top of solid rock, it's doable...otherwise it'll be a case of going as far down as they can, and then coming back out again.

Doug
Go to the top of the page
 
+Quote Post
ElkGroveDan
post Jun 30 2007, 04:22 PM
Post #73


Senior Member
****

Group: Admin
Posts: 4763
Joined: 15-March 05
From: Glendale, AZ
Member No.: 197



QUOTE (djellison @ Jun 30 2007, 08:13 AM) *
It all depends on what the terrain offers when we get closer. If it's just a tiny bit of sand on top of solid rock, it's doable...otherwise it'll be a case of going as far down as they can, and then coming back out again.

...perhaps doing the same on other "ramps" where different layers may avail themselves - if navigation is difficult here.


--------------------
If Occam had heard my theory, things would be very different now.
Go to the top of the page
 
+Quote Post
CosmicRocker
post Jul 1 2007, 06:08 AM
Post #74


Senior Member
****

Group: Members
Posts: 2228
Joined: 1-December 04
From: Marble Falls, Texas, USA
Member No.: 116



BrianL: That bright band is the safest, pre-impact bedrock they can reach. They will probably be able to go deeper than that, but as others have noted, further safe roving will depend on rover observations.

That Space-Multimedia site was a godsend. I was able to download the audio and listen to all of it. Squyres' performance was as amazing as it always is, but everyone else did just as well. That teleconference was one worth waiting for.

I am really excited that Steve noted that Opportunity would be traversing the first ever, good, vertical slice through an ejecta blanket, and did not want to waste the opportunity. I think this is important.

Sorting out the origin of the bright band, and whether it is due to the past atmosphere working down, or the past groundwater working up sounds like a good idea to me.

As for post-Victoria explorations, I can buy into a journey across the plains, looking at eroded craters for flowing water evidence and exotic cobbles along the way. It sounds like a good plan to me.


--------------------
...Tom

I'm not a Space Fan, I'm a Space Exploration Enthusiast.
Go to the top of the page
 
+Quote Post
Astro0
post Jul 2 2007, 10:52 PM
Post #75


Senior Member
****

Group: Admin
Posts: 3108
Joined: 21-December 05
From: Canberra, Australia
Member No.: 615



Hi All,

Just before Oppy heads into VC, I thought that I'd share a little SFX image.
The version here includes an inset image from the full-res version which is 6600x2418 and 16.5mb.
The full image is available here for download.

Attached Image

This is just a thumbnail version, see the link above.

I think that the scale is about right.
Thanks to Doug for the MER model used as the base for this image.
Can't wait until we see the real descent next week.

Enjoy
Astro0
Go to the top of the page
 
+Quote Post

9 Pages V  « < 3 4 5 6 7 > » 
Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 19th March 2024 - 04:15 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.