IPB

Welcome Guest ( Log In | Register )

Earth Return & Sample Science
nprev
post Oct 24 2020, 07:02 AM
Post #1


Merciless Robot
****

Group: Admin
Posts: 8783
Joined: 8-December 05
From: Los Angeles
Member No.: 602



Now that the 'boop' has been completed (with spectacular success!), we'll move the discussion to here for subsequent mission events. smile.gif


--------------------
A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
Go to the top of the page
 
+Quote Post
 
Start new topic
Replies
Tom Tamlyn
post Oct 24 2020, 06:55 PM
Post #2


Member
***

Group: Members
Posts: 444
Joined: 1-July 05
From: New York City
Member No.: 424



Thanks to for that link.

It was a great press conference. Even though Brian's helpful summary covered most of the the major points, it made fascinating listening, with detailed, clear, and fluent presentations and answers from Dante Lauretta and Thomas Zurbuchen, and sharp, business-like questions from well-informed reporters.

The stow operation is currently expected to begin on Tuesday. As Brian mentioned, the mission is seeking substantial extra DSN coverage in order to do something unusual for robotic spacecraft: conduct an operation interactively with "the ground in the loop." The revised stow plan will have a number of check points, at which the operation will pause while images are downloaded and analyzed to determine whether to proceed with the plan or try something different. As a result the stow operation is expected to last three days, instead of several hours as originally planned.

The previously scheduled activity of spinning the spacecraft with the arm extended to obtain a moment of inertia measurement has been cancelled, and Lauretta pretty much ruled out any other possibility for measuring the sample mass (as opposed to estimating the mass from images) prior to landing. However, he did seem to acknowledge that there had not been any occasion to think about a different way such a measurement could be taken during the return trip. I suppose it's possible they might come up with a way to tease some sample mass information out of trajectory telemetry during the return voyage.
Go to the top of the page
 
+Quote Post
Explorer1
post Oct 24 2020, 09:56 PM
Post #3


Senior Member
****

Group: Members
Posts: 2082
Joined: 13-February 10
From: Ontario
Member No.: 5221



QUOTE (Tom Tamlyn @ Oct 24 2020, 01:55 PM) *
However, he did seem to acknowledge that there had not been any occasion to think about a different way such a measurement could be taken during the return trip. I suppose it's possible they might come up with a way to tease some sample mass information out of trajectory telemetry during the return voyage.

Assuming the mass without the sample (including fuel and subtracting the nitrogen gas used) is known precisely enough, there should be a slight difference in how it 'handles' during maneuvers like the Earth return burn and any TCMs.
Go to the top of the page
 
+Quote Post
rlorenz
post Oct 25 2020, 10:16 PM
Post #4


Member
***

Group: Members
Posts: 610
Joined: 23-February 07
From: Occasionally in Columbia, MD
Member No.: 1764



QUOTE (Explorer1 @ Oct 24 2020, 05:56 PM) *
Assuming the mass without the sample (including fuel and subtracting the nitrogen gas used) is known precisely enough, there should be a slight difference in how it 'handles' during maneuvers like the Earth return burn and any TCMs.


In theory, yes (I think I remember reading a scifi story where a stowaway on a spacecraft is discovered this way). But in practice, this is a very small signal to look for (if you want to measure a 400g sample to 10%, as part of a 400kg spacecraft, that's a 0.01% precision)

I think thruster performance is probably not more consistent than 1%, maybe worse.

Measuring spin rates, and changes therein is something that can be done with exquisite precision, but more particularly putting the sample mass out on the TAGSAM arm gives a large moment arm, so the sample mass 'signal' component of the vehicle's moment of inertia. So having a viable retrieval of sample mass from this spin exercise does not mean you can do it with useful precision in a translation manoeuvre....
Go to the top of the page
 
+Quote Post
HSchirmer
post Oct 27 2020, 12:23 AM
Post #5


Member
***

Group: Members
Posts: 684
Joined: 24-July 15
Member No.: 7619



QUOTE (rlorenz @ Oct 25 2020, 10:16 PM) *
In theory, yes (I think I remember reading a scifi story where a stowaway on a spacecraft is discovered this way).

"The Cold Equations" https://docs.google.com/viewer?a=v&pid=...MmU1OTQ2YWViOWY
Go to the top of the page
 
+Quote Post

Posts in this topic
- nprev   Earth Return & Sample Science   Oct 24 2020, 07:02 AM
- - walfy   Boosted the shadows to reveal what I assume are th...   Oct 24 2020, 08:37 AM
- - dsmillman   The audio of the 10/23/2020 teleconference can be ...   Oct 24 2020, 01:30 PM
|- - Reed   QUOTE (dsmillman @ Oct 24 2020, 06:30 AM)...   Oct 25 2020, 06:32 AM
- - Tom Tamlyn   Thanks to for that link. It was a great press co...   Oct 24 2020, 06:55 PM
|- - JRehling   Looking at the apparent fragility of those "r...   Oct 24 2020, 07:24 PM
||- - HSchirmer   QUOTE (JRehling @ Oct 24 2020, 07:24 PM) ...   Oct 27 2020, 12:20 AM
|- - Explorer1   QUOTE (Tom Tamlyn @ Oct 24 2020, 01:55 PM...   Oct 24 2020, 09:56 PM
|- - rlorenz   QUOTE (Explorer1 @ Oct 24 2020, 05:56 PM)...   Oct 25 2020, 10:16 PM
|- - mcaplinger   QUOTE (rlorenz @ Oct 25 2020, 02:16 PM) I...   Oct 25 2020, 11:21 PM
||- - JRehling   Apollo 13 had a bit of a concern regarding sample ...   Oct 26 2020, 03:58 AM
|- - HSchirmer   QUOTE (rlorenz @ Oct 25 2020, 10:16 PM) I...   Oct 27 2020, 12:23 AM
- - marsbug   It's a nice problem to have in a way... but it...   Oct 24 2020, 09:18 PM
- - dtolman   So they cancelled the spin because visual inspecti...   Oct 24 2020, 10:42 PM
|- - Marcin600   QUOTE (dtolman @ Oct 25 2020, 12:42 AM) S...   Oct 25 2020, 12:33 AM
- - stevesliva   QUOTE (mcaplinger post Oct 23 2020 @ 06:56 P...   Oct 26 2020, 01:50 PM
- - jccwrt   If Bennu regolith is anywhere near as sticky as lu...   Oct 26 2020, 05:39 PM
- - Explorer1   Expedited stow begins tomorrow. Images will be ret...   Oct 26 2020, 08:41 PM
- - Marcin600   An excerpt from Dante Lauretta speech about the du...   Oct 26 2020, 09:42 PM
- - pbanholzer   Here's an article on contamination control for...   Oct 27 2020, 01:10 AM
- - Hungry4info   OSIRIS-REx in the Midst of Stow https://www.astero...   Oct 28 2020, 10:47 PM
- - Marcin600   NASA will host a media teleconference at 4 p.m. ED...   Oct 29 2020, 05:05 PM
- - Marcin600   From teleconference: 400 g was visible in the came...   Oct 29 2020, 08:52 PM
- - Explorer1   Dante just said that the navcam was taking images ...   Oct 29 2020, 09:03 PM
|- - mcaplinger   QUOTE (Explorer1 @ Oct 29 2020, 01:03 PM)...   Oct 30 2020, 06:40 PM
- - Marcin600   From teleconference (+/-): "...The fact that ...   Oct 29 2020, 09:25 PM
- - Marcin600   From teleconference (+/-): "...The ship's...   Oct 29 2020, 10:16 PM
- - Marcin600   Once again Dante Lauretta statement about Bennu...   Oct 30 2020, 06:05 PM
- - Hungry4info   Absolutely spectacular video of the sampling. We s...   Oct 30 2020, 09:59 PM
- - Marcin600   A little lightened. Could it be a crater? (dug by ...   Oct 31 2020, 01:29 AM
- - Marcin600   Animated gif   Oct 31 2020, 01:35 AM
- - FOV   I agree Hungry4info. Spectacular. My messing abo...   Oct 31 2020, 01:37 AM
- - Marcin600   a little earlier - and closer   Oct 31 2020, 01:48 AM
- - Marcin600   edge of the hole ?   Oct 31 2020, 01:57 AM
- - Marcin600   first stages   Oct 31 2020, 02:09 AM
- - Explorer1   Wow! dusting off the old swear jar! The l...   Oct 31 2020, 02:22 AM
- - Marcin600   the second stage I wonder if all these thin, elon...   Oct 31 2020, 02:29 AM
- - Brian Swift   Before and After. Frames 274 and 469 from NavCam2_...   Oct 31 2020, 07:25 AM
|- - Marcin600   QUOTE (Brian Swift @ Oct 31 2020, 08:25 A...   Oct 31 2020, 12:27 PM
- - Greenish   Agree that these are fantastic images, most inspir...   Oct 31 2020, 04:54 PM
|- - Greenish   And here are two more, from adjacent frames (no sh...   Oct 31 2020, 06:01 PM
- - Marcin600   My attempt to make "before-and-after" an...   Nov 1 2020, 01:05 AM
- - Marcin600   Now it looks to me as if a cloud of debris was com...   Nov 1 2020, 02:29 AM
- - Greenish   Animated movie of the 'blast,' starting fr...   Nov 1 2020, 04:46 AM
|- - Guillermo Abramson   QUOTE (Greenish @ Nov 1 2020, 01:46 AM) A...   Nov 4 2020, 12:23 PM
|- - Marcin600   QUOTE (Greenish @ Nov 1 2020, 05:46 AM) A...   Nov 4 2020, 05:12 PM
- - monty python   Wow Greenish! Emptied my wallet into the swear...   Nov 1 2020, 05:31 AM
- - Marcin600   My rough attempt to put the post sampling picture ...   Nov 14 2020, 04:35 AM
- - Marcin600   And also an attempt to superimpose a post sampling...   Nov 14 2020, 04:37 AM
- - Marcin600   SamCam and NavCam 2 Imaging Footprint During TAG -...   Nov 17 2020, 08:55 PM
- - Marcin600   I added my own interpretation of the TAGSAM head t...   Nov 18 2020, 09:36 PM
- - Marcin600   Considerations on the extended OSIRIS-REx mission ...   Jan 19 2021, 08:19 PM
- - stevesliva   *Orbit* Apophis. Wow. The duration post-sample ...   Jan 19 2021, 08:46 PM
|- - vjkane   QUOTE (stevesliva @ Jan 19 2021, 12:46 PM...   Jan 19 2021, 11:01 PM
- - Explorer1   I've read about some other proposals for Apoph...   Jan 20 2021, 03:19 AM
|- - JRehling   2021: Everyone's hoping that Osiris-Rex will h...   Jan 20 2021, 03:28 AM
|- - vjkane   QUOTE (Explorer1 @ Jan 19 2021, 07:19 PM)...   Jan 20 2021, 04:12 PM
|- - Marcin600   QUOTE (Explorer1 @ Jan 20 2021, 04:19 AM)...   Jan 21 2021, 07:48 PM
- - Explorer1   Yes, those are what I read, thanks for finding it...   Jan 21 2021, 12:35 AM
- - Explorer1   A final Bennu flyby is planned for April to check ...   Jan 27 2021, 04:09 PM
|- - Marcin600   QUOTE (Explorer1 @ Jan 27 2021, 05:09 PM)...   Jan 30 2021, 03:21 PM
- - Marcin600   "The International Astronomical Union (IAU) h...   Feb 5 2021, 12:57 AM
- - Marcin600   A final flyby of Bennu (and Nightingale) on April ...   Feb 9 2021, 01:52 PM
- - Marcin600   „This image...was taken...on March 4, from a dista...   Mar 8 2021, 08:37 PM
- - Marcin600   "...As of Mar. 12, the spacecraft was about 1...   Mar 15 2021, 08:22 PM
- - alan   Saw this on twitter: QUOTE Jason Major @JPMajor B...   Mar 22 2021, 10:12 PM
- - Marcin600   "The OSIRIS-REx spacecraft... is currently ab...   Mar 30 2021, 03:55 PM
- - Marcin600   https://www.asteroidmission.org/?latest-new...-ast...   Apr 8 2021, 04:31 PM
- - pbanholzer   Marc - Thanks for the updates. Do you know what t...   Apr 10 2021, 07:25 PM
- - Marcin600   I was unable to find information about the exact p...   Apr 13 2021, 06:00 PM
- - pbanholzer   Thanks so much for all of this. More than I expec...   Apr 15 2021, 04:33 PM
- - Explorer1   Images released: https://www.nasa.gov/feature/godd...   Apr 15 2021, 06:20 PM
- - Explorer1   Press conference and new images to be released Mon...   May 7 2021, 02:34 PM
- - Marcin600   Jun 04, 2021: "NASA’s OSIRIS-REx spacecraft i...   Jun 8 2021, 05:46 PM
- - vjkane   NASA has put out its call for proposals for extend...   Jul 16 2021, 04:23 AM
- - Hungry4info   The OSIRIS-REx team used an alternative method to ...   Sep 14 2021, 01:40 AM
|- - vjkane   QUOTE (Hungry4info @ Sep 13 2021, 05:40 P...   Sep 14 2021, 03:11 PM
|- - fredk   QUOTE (vjkane @ Sep 14 2021, 04:11 PM) Th...   Sep 14 2021, 04:24 PM
- - Phil Stooke   I have updated my Bennu map to include the date of...   Nov 7 2021, 10:37 PM
|- - JRehling   Beautiful work, Phil. And it's fun to see a gl...   Nov 7 2021, 11:41 PM
- - Explorer1   A very interesting NYT article about the Apophis f...   Dec 16 2021, 06:45 PM
|- - StargazeInWonder   The proposed extension to explore Apophis has been...   Apr 25 2022, 09:02 PM
- - Explorer1   Summary of new results on the TAG event: https://w...   Jul 7 2022, 07:22 PM
- - Marcin600   Another two (fairly) new articles on processes on ...   Aug 21 2022, 08:23 AM
- - Marcin600   Only 6 months left until the arrival of the Bennu ...   Mar 25 2023, 07:36 PM
- - Holder of the Two Leashes   OSIRIS-REx has sucessfully completed is final cour...   Sep 20 2023, 03:46 PM
- - Xerxes   QUOTE 3 millimeters per second That's surpris...   Sep 21 2023, 01:44 PM
- - stevesliva   Release is September 24. I'd imagine that 3mm...   Sep 21 2023, 02:30 PM
- - djellison   QUOTE (Xerxes @ Sep 21 2023, 05:44 AM) .....   Sep 21 2023, 08:24 PM
- - Marcin600   Sunday, Sept. 24 10 a.m. — Live coverage of ...   Sep 24 2023, 12:29 AM
- - Hungry4info   The sample return capsule has been released and OS...   Sep 24 2023, 12:05 PM
- - kenny   And the spacecraft bus has been officially renamed...   Sep 24 2023, 01:35 PM
- - kenny   NASA web site is very slow. Same is on YouTube he...   Sep 24 2023, 02:20 PM
- - Hungry4info   Helicopters have started taking off. There are fou...   Sep 24 2023, 02:34 PM
- - nprev   Entry interface.   Sep 24 2023, 02:43 PM
- - Hungry4info   Parachute deployed!   Sep 24 2023, 02:48 PM
- - Hungry4info   Capsule is on the ground.   Sep 24 2023, 02:53 PM
- - nprev   YES!!!! EDL is always a nail-biter...   Sep 24 2023, 02:54 PM
- - Bjorn Jonsson   Success! Touchdown slightly ahead of schedule ...   Sep 24 2023, 02:54 PM
- - kenny   Great news! After all those years in deep spa...   Sep 24 2023, 02:58 PM
3 Pages V   1 2 3 >


Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 26th April 2024 - 04:36 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.