IPB

Welcome Guest ( Log In | Register )

8 Pages V  < 1 2 3 4 > »   
Reply to this topicStart new topic
Lucy, Discovery Mission 13 - a grand tour of the Jupiter Trojans
Floyd
post Oct 16 2021, 04:49 PM
Post #16


Member
***

Group: Members
Posts: 941
Joined: 4-September 06
From: Boston
Member No.: 1102



I also watched the launch this morning--it is always breathtaking. I understand the huge solar panels unfolded properly.


--------------------
Go to the top of the page
 
+Quote Post
Tom Tamlyn
post Oct 17 2021, 01:59 AM
Post #17


Member
***

Group: Members
Posts: 447
Joined: 1-July 05
From: New York City
Member No.: 424



The best general media article I’ve run across concerning the Lucy Mission is this one in the New York Times. (I assume it’s paywalled, although the NYT is a little more generous with free articles than it was.)

https://www.nytimes.com/article/nasa-lucy-t...-asteroids.html

The article is nicely written, features some particularly good graphics, and most importantly, feels more comprehensive than is typical for the twenty-first century NYT science section.

This was a mild surprise. I’m a life-long reader and admirer of the New York Times science desk. However, since the MER rover missions renewed and intensified my interest in planetary science in 2004, I’ve frequently felt that the NYT’s fine writers were not allowed enough ink to do do justice to planetary missions. I began to rely much more on specialist journals and online sources, especially Emily Lakdawalla, and particularly during her time at the Planetary Society, and of course this forum.

The article's author, David W. Brown, is a freelancer who has apparently just published a book on the Europa Clipper mission with the following title:

QUOTE
THE MISSION, or: How a Disciple of Carl Sagan, an Ex-Motocross Racer, a Texas Tea Party Congressman, the World's Worst Typewriter Saleswoman, California Mountain People, and an Anonymous NASA Functionary Went to War with Mars, Survived an Insurgency at Saturn, Traded Blows with Washington, and Stole a Ride on an Alabama Moon Rocket to Send a Space Robot to Jupiter in Search of the Second Garden of Eden at the Bottom of an Alien Ocean Inside of an Ice World Called Europa (A True Story)

I'm not a fan of goofy long book titles that don't include useful search terms in the first few words, or in this case, anywhere at all, but on the strength of Brown's article about Lucy, I'm going to read his book.
Go to the top of the page
 
+Quote Post
Explorer1
post Oct 17 2021, 02:59 AM
Post #18


Senior Member
****

Group: Members
Posts: 2113
Joined: 13-February 10
From: Ontario
Member No.: 5221



I posted a minor review of the audiobook in the Europa Clipper thread: http://www.unmannedspaceflight.com/index.p...st&p=251818
He's a good writer, though naturally he can only write about non-confidential subject matter, so he is limited to some degree.
Go to the top of the page
 
+Quote Post
stevesliva
post Oct 17 2021, 03:08 AM
Post #19


Senior Member
****

Group: Members
Posts: 1598
Joined: 14-October 05
From: Vermont
Member No.: 530



Re: NYT: this reads like a Science Tuesday section front page, and that's where I'd expect to see it in print.
Go to the top of the page
 
+Quote Post
JTN
post Oct 17 2021, 09:54 AM
Post #20


Member
***

Group: Members
Posts: 204
Joined: 20-November 05
From: Mare Desiderii
Member No.: 563



QUOTE (Holder of the Two Leashes @ Oct 15 2021, 05:11 PM) *
Hmmm. Since this Atlas launch will be without any SRBs, a couple of shock diamonds might be just barely visible in the far end of the exhaust of the rocket.

I think this tweet (direct image link) might show such.

Also, the Spaceflight Now article has "A tiny diamond buried deep inside the L’TES spectrometer acts as a beam splitter".
Go to the top of the page
 
+Quote Post
Decepticon
post Oct 18 2021, 03:39 AM
Post #21


Senior Member
****

Group: Members
Posts: 1278
Joined: 25-November 04
Member No.: 114



https://spacenews.com/nasa-investigating-is...cy-solar-array/
Go to the top of the page
 
+Quote Post
Explorer1
post Oct 19 2021, 02:23 PM
Post #22


Senior Member
****

Group: Members
Posts: 2113
Joined: 13-February 10
From: Ontario
Member No.: 5221



They're optimistic that it's not a major issue: RCS thrusters worked already, main change has been a delay in deploying the instrument platform:

https://spaceflightnow.com/2021/10/18/nasa-...lar-array-snag/
EDIT: More details, directly from the team:
https://blogs.nasa.gov/lucy/2021/10/19/nasa...s-solar-arrays/
Go to the top of the page
 
+Quote Post
Hungry4info
post Oct 24 2021, 07:49 PM
Post #23


Senior Member
****

Group: Members
Posts: 1453
Joined: 26-July 08
Member No.: 4270



Lucy update. We're now in cruise mode, with the instrument platform deployed. They're going to turn the spacecraft to various attitudes to try to use the current measurement from the stuck array to determine how far it deployed to better inform how to fix it. https://scitechdaily.com/nasa-issues-update...ay-problem/amp/


--------------------
-- Hungry4info (Sirius_Alpha)
Go to the top of the page
 
+Quote Post
Explorer1
post Oct 29 2021, 01:44 AM
Post #24


Senior Member
****

Group: Members
Posts: 2113
Joined: 13-February 10
From: Ontario
Member No.: 5221



https://blogs.nasa.gov/lucy/2021/10/27/lucy...in-cruise-mode/
Next attempt to fully deploy no earlier than November 16th. Instrument checkout going on as planned, some minor manouvers have been completed.
Array is 75 - 95 % deployed, team estimates.
Go to the top of the page
 
+Quote Post
lcs
post Oct 30 2021, 12:53 PM
Post #25


Newbie
*

Group: Members
Posts: 2
Joined: 27-May 08
Member No.: 4144



Something similar happened on Galileo. Possible explanation?

https://www.mdpi.com/2075-4442/9/8/72?type=...e&version=2
Go to the top of the page
 
+Quote Post
stevesliva
post Oct 30 2021, 02:26 PM
Post #26


Senior Member
****

Group: Members
Posts: 1598
Joined: 14-October 05
From: Vermont
Member No.: 530



The mechanisms are different, and Galileo was in storage for too many years.

The status report above mentions a 'lanyard'. There is a timelapse video from a deployment test here: https://www.youtube.com/watch?v=6vjK9vGEw5Q

My guess is that the lanyard they mention is seen here. It starts pulling around the fulcrum at the center of the array, and then pulls across the screen, and then is off screen.
Go to the top of the page
 
+Quote Post
Explorer1
post Oct 30 2021, 02:29 PM
Post #27


Senior Member
****

Group: Members
Posts: 2113
Joined: 13-February 10
From: Ontario
Member No.: 5221



Lucy was never in storage for an extended period due to delays. I'm sure they're thinking over every possibility. Although we all hope the array finishes deploying, I have been thinking that if this isn't fixed by the time of the Earth flyby next year, the low altitude combined with the size of the arrays, might make it possible to resolve the stuck array directly with Earth-based imagery?
Go to the top of the page
 
+Quote Post
mcaplinger
post Oct 30 2021, 05:31 PM
Post #28


Senior Member
****

Group: Members
Posts: 2547
Joined: 13-September 05
Member No.: 497



QUOTE (Explorer1 @ Oct 30 2021, 07:29 AM) *
...possible to resolve the stuck array directly with Earth-based imagery?

See https://www.jpl.nasa.gov/nmp/st8/tech_paper...20NGU%20ST8.pdf for some information about how Ultraflex arrays work (BTW, ST8 never flew as far as I know). I don't know what kinds of position information or other telemetry (e.g., motor current) they get during deployment. What's been said suggests that all they get is a single binary flag showing full latching, but I doubt that's true.

It's not at all obvious to me if images, especially ground-based, would be of any use whatsoever to fixing the problem. The TTCAM cameras could in theory produce out-of-focus images of the spacecraft, but I don't know if their placement and platform articulation would allow anything useful of the panel (links to a paper on those cameras upthread.)

There's a lengthy, mostly off-topic discussion of this at https://forum.nasaspaceflight.com/index.php?topic=46685.0 if you're into that kind of thing.


--------------------
Disclaimer: This post is based on public information only. Any opinions are my own.
Go to the top of the page
 
+Quote Post
JRehling
post Oct 31 2021, 02:30 AM
Post #29


Senior Member
****

Group: Members
Posts: 2530
Joined: 20-April 05
Member No.: 321



An object 300 km from a telescope on the ground might enable imagery with resolution as good as about 10 cm per pixel… but that assumes a lot, including good weather at the sub-spacecraft point, which is completely beyond anyone's control or ability to predict, as well as two geometric factors that are knowable in advance, but not known to me: Will the spacecraft be near closest approach over land vs. the 70% of Earth that is water, and will the spacecraft be in sunlight at the time of closest approach, but not lost in daylight? This all sounds well below 50% probability, but not impossible.
Go to the top of the page
 
+Quote Post
mcaplinger
post Oct 31 2021, 03:00 AM
Post #30


Senior Member
****

Group: Members
Posts: 2547
Joined: 13-September 05
Member No.: 497



QUOTE (JRehling @ Oct 30 2021, 06:30 PM) *
An object 300 km from a telescope on the ground might enable imagery with resolution as good as about 10 cm per pixel…

Color me skeptical that this is 1) possible or 2) useful, but feel free to check out the geometry -- the best trajectory info so far is https://naif.jpl.nasa.gov/pub/naif/LUCY/ker...-TCM36-P_v2.bsp


--------------------
Disclaimer: This post is based on public information only. Any opinions are my own.
Go to the top of the page
 
+Quote Post

8 Pages V  < 1 2 3 4 > » 
Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 31st October 2024 - 11:28 PM
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.