Lucy, Discovery Mission 13 - a grand tour of the Jupiter Trojans Options

[Floyd]

With the low cost and weight of small cameras, I'm surprised there were not two cameras dedicated to viewing the solar arrays and documenting their deployment.

[mcaplinger]

With the low cost and weight of small cameras, I'm surprised there were not two cameras dedicated to viewing the solar arrays and documenting their deployment.

The overall system cost is probably not as low as you think, and it's not at all clear that documenting the deployment would help you fix a problem. Without knowing the details of the system it's impossible to know. There's more than enough poorly-informed discussion of this at the link I provided above.

If you want small space-rated cameras we would be happy to sell you some, and in fact there are two on Lucy: https://www.msss.com/news/index.php?id=131

[JRehling]

I don't have the software to turn that kernel data into the flyby specifics, but I'll emphasize that it seems unlikely that a best-case scenario for ground imaging would occur.

If it did, I still maintain that decimeter-scale resolution is possible, at least if we were trying to determine the degree that the solar array had deployed, from a continuum of known possibilities. Measuring the separation between two linear features measuring many pixels long allows for much greater accuracy than trying to image an unknown object. It would be quite similar to the situation where Vernier acuity is measured. As the Wikipedia article (accurately) states, "vernier acuity exceeds acuity by far."

https://en.wikipedia.org/wiki/Vernier_acuity

Here is an image of the ISS that approaches the best case resolution. As a comparison, this telescope has something like 3x the aperture of HiRise, which images subjects 300 km away.

https://m.facebook.com/MilroyCoonabarabran/...8555909/?type=3

But, again, there's no reason other than hope that a single opportunity would achieve results like the best of virtually unlimited opportunities to image the ISS. I don't predict a productive outcome for such an effort.

[bobik]

The overall system cost is probably not as low as you think, and it's not at all clear that documenting the deployment would help you fix a problem.

Is that so? The BepiColombo project added 3 small monitoring cameras to a completely integrated spacecraft less than two years before launch, and ESA - especially ESA's Science Programme isn't known for swimming in money. Yes, however, 20 percent uncertainty of the deployment state doesn't help to fix or assess the problem either.

[mcaplinger]

The BepiColombo project added 3 small monitoring cameras to a completely integrated spacecraft less than two years before launch, and ESA - especially ESA's Science Programme isn't known for swimming in money.

Unless you can produce an actual cost figure then this is at best circumstantial. I have a pretty good idea of how much it would have cost on Lucy, but can't discuss specifics.

This is all 20-20 hindsight. What I don't know is how much telemetry of the array state they get. Obviously they weren't expecting a problem.

[Marcin600]

"...The test data and findings suggest the lanyard may not have wound on the spool as intended. Testing continues to determine what caused this outcome, and a range of scenarios are possible. The team isn’t planning to attempt to move or further characterize the current state of the solar array deployment before Wednesday, Dec. 1, at the earliest."
"...Checkouts for the Lucy instruments were successfully completed Nov. 8, and all instruments are working normally..."

https://blogs.nasa.gov/lucy/2021/11/18/lucy...-checkout-a-ok/

https://twitter.com/NASASolarSystem/status/...393961629757450

[JTN]

NASA Zeroing in on Path Forward for Lucy Solar Array (8 Dec)

NASA now has data on all 10 gores confirming they are open, producing power as expected, and not stuck together.

[MahFL]

NASA Zeroing in on Path Forward for Lucy Solar Array (8 Dec)

Sounds good.

[Decepticon]

Update on Solar array.

https://spacenews.com/cause-of-lucy-solar-a...lem-identified/

[john_s]

We're planning the first step of the Lucy solar array re-deployment attempt on the week of May 9th- see this blog post for details. Fingers crossed!

John

[john_s]

Two Lucy items of interest:

1) The first step of the solar array redeployment test was completed last week: https://blogs.nasa.gov/lucy/2022/05/10/nasa...oyment-attempt/. Data analysis is under way.

2) We'll be making a movie of tonight's lunar eclipse! As far as I know, this will be the first movie of a lunar eclipse from deep space, though someone here might be able to correct me. See http://lucy.swri.edu/2022/05/12/LunarEclipse.html

John

[Explorer1]

And here it is! https://www.nasa.gov/feature/goddard/2022/n...a-lunar-eclipse

[StargazeInWonder]

What a beautiful result. It might be surprising to people who've spotted a lunar eclipse and could easily see the Moon during totality that the eclipsed Moon is much darker than the full Moon, by a factor of hundreds or more. So, in a video that does not adjust the brightness to compensate, the Moon will seem simply to go black.

[john_s]

Here's a repeating version, which I prefer to the version that was posted on NASA.



John

[JTN]

Tidbits on Lucy solar array deployment:

NASA’s Lucy Mission Continues Solar Array Deployment Process (Lucy blog, June 8): not latched yet, but four attempts (May 9, May 12, May 26, June 2) all show array continuing to open and stiffen. More attempts are possible.

Efforts continue to fully deploy Lucy solar array (spacenews,com, also June 8) has quotes from Hal Levison:

“That’s allowing us to make significant process towards latch, but we’re not latched yet,” Hal Levison, principal investigator for Lucy at the Southwest Research Institute, said in a presentation at a meeting of NASA’s Small Bodies Assessment Group June 8. “We are seeing significant tensioning of the array.”

That tensioning, he said, is a positive sign even though the array has not latched into place. “It makes it likely that, even if we don’t get the thing latched, we’ll be able to fly the mission as-is,” he said, noting the array, in its current configuration, is generating more than 90% of its planned power.