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

[Explorer1]

New moon of Polymele discovered (due to a recent occultation)!

Good summary here, including of the array issue:

https://spaceflightnow.com/2022/06/14/nasa-...asteroid-probe/

One of the Trojan asteroids on Lucy’s tour, named Polymele, has a companion. Scientists discovered an apparent satellite of Polymele during a ground-based occultation observation in March, when Polymele briefly passed in front of a star, temporarily blocking its light from reaching Earth.

The occultation observations were intended to help the Lucy science team determine the shape of Polymele, which only appears as a point of light in telescope images.

“We got a really nice projected shape of Polymele, and then we were very surprised to detect an object about 200 kilometers (120 miles) away from Polymele,” Levison said last week in a presentation to NASA’s Small Bodies Advisory Group. “It’s 5 kilometers (3 miles) in diameter, and it’s sitting almost exactly in Polymele’s equatorial plane.”

[Explorer1]

Good news for the array:

https://www.nasa.gov/feature/goddard/2022/n...llions-of-miles

The mission now estimates that Lucy’s solar array is between 353 degrees and 357 degrees open (out of 360 total degrees for a fully deployed array). While the array is not fully latched, it is under substantially more tension, making it stable enough for the spacecraft to operate as needed for mission operations.

[Steve G]

Has there been any estimates released on the orbital period of the newly discovered moon? Specifically, are they mutually tidally locked to the other?

[Toma B]

Does anybody know when do we get the first images from Earth's gravity assist?
This should be a great test of what those cameras can do.
Can Lucy take better image sequences than Galileo or Messenger spacecraft during this flyby?

[mcaplinger]

Does anybody know when do we get the first images from Earth's gravity assist?

Speculation as we have no operational role in this mission --

DSN Now shows 20 kbit/s down, most likely on the LGA/MGA due to spacecraft orientation. I doubt if we will see anything until after the flyby is complete and they can send the data back at a higher rate.

It took about 2 months before the 14 Feb 2022 star images were released ( https://www.nasa.gov/feature/goddard/2022/c...lucy-spacecraft ) but hopefully some flyby images will show up more quickly.

[john_s]

We'll be imaging the Earth and Moon a few times during the flyby, but no Galileo-style color movies- the science cameras are rather limited in what they can do at 1 AU, due to overexposure. We're hoping for some nice images of the Moon after Earth closest approach, however.

I'm hoping to see the spacecraft itself with binoculars on Sunday morning, from Western Nebraska where we've come to avoid clouds in Colorado. It should be much brighter from north-west Australia, just before closest approach, for anyone in that part of the world. See http://lucy.swri.edu/SpotTheSpacecraft-EGA1.html

John

[mcaplinger]

I doubt if we will see anything until after the flyby is complete and they can send the data back at a higher rate.

Lucy downlinking now at 353 kb/sec to DSS14.

[mcaplinger]

https://www.nasa.gov/image-feature/goddard/...-gravity-assist

I was sort of expecting science instrument images to be highlighted over T2CAM images, but I'm not complaining.

[john_s]

It's just a matter of what was ready when. Science camera images will follow shortly.

John

[Bill Harris]

snip

I'm hoping to see the spacecraft itself with binoculars on Sunday morning, from Western Nebraska where we've come to avoid clouds in Colorado. It should be much brighter from north-west Australia, just before closest approach, for anyone in that part of the world. See http://lucy.swri.edu/SpotTheSpacecraft-EGA1.html

John

Still, 6th-7th mag from North America shouldn't be that impossible with binocs. Seems that the "proper motion" of the spacecraft won't be all that large.
Even if you get clouded out, there are still 2 flybys to possibly try again.

--Bill

[john_s]

For the record, I didn't catch it in my binoculars, but we saw it live with an 11" telescope, which was quite thrilling. We followed it for about 30 minutes until we lost it in twilight- it got rapidly slower and dimmer during that time as it climbed away, in the general direction of the Moon.

John

[climber]

Here is the Moon : https://www.nasa.gov/image-feature/goddard/...-views-the-moon

[Hungry4info]

We're getting a bonus flyby! Lucy will visit the small main belt asteroid 1999 VD57 on 01 Nov 2023.
https://www.nasa.gov/feature/goddard/2023/n...asteroid-target

[Explorer1]

Combined with the new moons discovered fro the primary targets, I think they're trying to beat Cassini's record...

[john_s]

Here are the first Lucy images (movies, in fact) of four of our five primary Trojan asteroid targets:

NASA image release

John (Lucy deputy project scientist)