IPB

Welcome Guest ( Log In | Register )

9 Pages V  « < 4 5 6 7 8 > »   
Reply to this topicStart new topic
HAMO, (aka High Altitude Mapping Orbit)
belleraphon1
post Oct 3 2011, 11:34 PM
Post #76


Member
***

Group: Members
Posts: 724
Joined: 29-December 05
From: NE Oh, USA
Member No.: 627




The big thing to me was Dr. Russell's mention of an appreciable iron core, detected though the denity and j2 measurements. So we have a differentiated body.
What a shame they lost the magnetometer to budget. Dr. Russell even mentioned that when a questioner asked what other instruments he would have liked included.

Craig

Go to the top of the page
 
+Quote Post
dilo
post Oct 4 2011, 08:33 PM
Post #77


Senior Member
****

Group: Members
Posts: 2492
Joined: 15-January 05
From: center Italy
Member No.: 150



Update with zoomed scale on last 3 weeks:
Attached Image

Height in the last days has been oscillating between 664 and 701 km above nominal 265 km radius.


--------------------
I always think before posting! - Marco -
Go to the top of the page
 
+Quote Post
MarkG
post Oct 7 2011, 04:12 AM
Post #78


Member
***

Group: Members
Posts: 117
Joined: 31-October 08
Member No.: 4473



Full inline quote - with image - removed - ADMIN

Looking at that orbital data, I would have to wonder if that is pretty much the closest to a constant-speed, constant-radius, circular orbit Dawn can manage, with Vesta so flattened and asymmetric.

I'm sure the little variations are yielding a picture of the source mass distribution. I can't devolve the gravity figure from the orbit data, doing the math in my head, unless I've had at least 2 beers, and it IS a weeknight. Maybe someone else can help...
Go to the top of the page
 
+Quote Post
stevesliva
post Oct 9 2011, 05:54 PM
Post #79


Senior Member
****

Group: Members
Posts: 1164
Joined: 14-October 05
From: Seattle
Member No.: 530



Today's image of the day is pretty fun to look at:
http://dawn.jpl.nasa.gov/multimedia/imageo...p?date=20111009

A lot going on there.

Also-- does anyone know of a good RSS feed to get the image of the day into their reader?
Go to the top of the page
 
+Quote Post
monty python
post Oct 10 2011, 05:26 AM
Post #80


Member
***

Group: Members
Posts: 116
Joined: 2-March 06
Member No.: 692



Yea. It looks like there is a darker (older) layer of material the crater punched into. Is the darker material more loosely consolidated, as it looks to me that the north and south sides of the crater with more dark material slumped, and the pits in the crater bottom are in dark material.

I can't get over how the rays left grooves in the surface. I'm trying to picture in my mind how the impact happened and could do that.
Go to the top of the page
 
+Quote Post
Juramike
post Oct 10 2011, 01:34 PM
Post #81


Senior Member
****

Group: Moderator
Posts: 2711
Joined: 10-November 06
From: Pasadena, CA
Member No.: 1345



Low gravity small body dynamics? The debris flying out gives a trajectory effectively parallel to the ground perhaps and just plows the surface for a really long way?


--------------------
Some higher resolution images available at my photostream: http://www.flickr.com/photos/31678681@N07/
Go to the top of the page
 
+Quote Post
alan
post Oct 11 2011, 04:36 PM
Post #82


Senior Member
****

Group: Members
Posts: 1628
Joined: 20-November 04
From: Iowa
Member No.: 110



This paper written a few months before Dawn reached Vesta claims the impact near Vesta's south pole would have caused Vesta's axis to reorient and made some predictions based on this. Are we seeing any of the features they predicted?
Reoritaion of Vesta: Gravity and Tectonic Predictions
Go to the top of the page
 
+Quote Post
stevesliva
post Oct 11 2011, 05:35 PM
Post #83


Senior Member
****

Group: Members
Posts: 1164
Joined: 14-October 05
From: Seattle
Member No.: 530



3-D perspective view of the south:
http://dawn.jpl.nasa.gov/multimedia/vesta_...olar_region.asp
Go to the top of the page
 
+Quote Post
charborob
post Oct 11 2011, 05:53 PM
Post #84


Member
***

Group: Members
Posts: 407
Joined: 21-September 07
From: Québec, Canada
Member No.: 3908



QUOTE (stevesliva @ Oct 11 2011, 01:35 PM) *

That image has 1.5x vertical exaggeration (Why? To make it more spectacular?). Here is the same image without vertical exaggeration (contrast enhanced):
Attached Image
Go to the top of the page
 
+Quote Post
chuckclark
post Oct 11 2011, 06:02 PM
Post #85


Member
***

Group: Members
Posts: 123
Joined: 20-November 07
Member No.: 3967



QUOTE (charborob @ Oct 11 2011, 12:53 PM) *
That image has 1.5x vertical exaggeration (Why? To make it more spectacular?). Here is the same image without vertical exaggeration (contrast enhanced):


"That image" also flattens the surface. Why? Someone please tell me!
Can you restore the curvature?
Go to the top of the page
 
+Quote Post
charborob
post Oct 11 2011, 08:54 PM
Post #86


Member
***

Group: Members
Posts: 407
Joined: 21-September 07
From: Québec, Canada
Member No.: 3908



QUOTE (chuckclark @ Oct 11 2011, 02:02 PM) *
"That image" also flattens the surface. Why? Someone please tell me!
Can you restore the curvature?

The caption of the released image explains it thus:
"This perspective shows the topography, but removes the overall curvature of Vesta, as if the giant asteroid were flat and not rounded. An observer on Vesta would not have a view like this, because the distant features would disappear over the curvature of the horizon."
Someone with the necessary knowledge and appropriate software (that includes some members of this forum) and with access to the original DEM file (that could be more problematic) could produce a view of the surface of Vesta showing the curvature.
Go to the top of the page
 
+Quote Post
ngunn
post Oct 11 2011, 10:22 PM
Post #87


Senior Member
****

Group: Members
Posts: 3113
Joined: 4-November 05
From: North Wales
Member No.: 542



What a mess. Scientific disinformation in a place you wouldn't expect it. Thanks, members, for pointing it out. (So, can we pruduce the correct version here???)
Go to the top of the page
 
+Quote Post
stevesliva
post Oct 12 2011, 03:24 AM
Post #88


Senior Member
****

Group: Members
Posts: 1164
Joined: 14-October 05
From: Seattle
Member No.: 530



I would hazard a guess that projecting onto an plane allows for better comparisons to other craters. Except that if you're doing that, you might want to de-exaggerate the height of things, because you're probably comparing to craters on worlds with higher gravity.
Go to the top of the page
 
+Quote Post
dilo
post Oct 12 2011, 04:10 AM
Post #89


Senior Member
****

Group: Members
Posts: 2492
Joined: 15-January 05
From: center Italy
Member No.: 150



QUOTE (ngunn @ Oct 11 2011, 10:22 PM) *
What a mess. Scientific disinformation in a place you wouldn't expect it. Thanks, members, for pointing it out. (So, can we pruduce the correct version here???)

I suspect that realistic version (curved horizon instead of a flat map height) would be less interesting because it would show far less surface and would be very similar to Survey Orbit images, due to limited grid resolution. Things will be different when we will have a complete topography based on HAMO/LAMO data, in this case a virtual tour above surface would be really nice... rolleyes.gif


--------------------
I always think before posting! - Marco -
Go to the top of the page
 
+Quote Post
chuckclark
post Oct 12 2011, 10:55 AM
Post #90


Member
***

Group: Members
Posts: 123
Joined: 20-November 07
Member No.: 3967



QUOTE (dilo @ Oct 11 2011, 11:10 PM) *
Things will be different when we will have a complete topography based on HAMO/LAMO data, in this case a virtual tour above surface would be really nice... rolleyes.gif


Then, perhaps, it was a pragmatic decision taken on limited data or capability (this I could feel better about), rather than a willful aesthetic judgment within a large range of alternatives.
Go to the top of the page
 
+Quote Post

9 Pages V  « < 4 5 6 7 8 > » 
Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 2nd September 2014 - 09:15 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 a project of the Planetary Society and is funded by donations from visitors and members. Help keep this forum up and running by contributing here.