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Scott Tilley @coastal8049.bsky.social · 3d

More bad news from JPL.

~550 more people to be laid off on October 14th.

www.jpl.nasa.gov/news/jpl-wor...

JPL Workforce Update

A message from JPL Director Dave Gallagher

www.jpl.nasa.gov

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Reposted by Scott Tilley

Andrew Jones @andrewjonesspace.bsky.social · 15d

CNSA has released an image of Tianwen-2 in deep space using a robotic arm, giving us a proper look at the spacecraft and return capsule for delivering samples from near Earth asteroid 469219 Kamoʻoalewa. Tianwen-2 has been in space for 125 days, is 45 million km from Kamoʻoalewa.

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Scott Tilley @coastal8049.bsky.social · 21d

CGO in the IMAP and SWFO-L1 mob also LHCP and emitting a nice strong signal today.

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Scott Tilley @coastal8049.bsky.social · 21d

SWFO-L1 is LHCP and producing really nice signals on S-band. Likely easily decodable data. The mission is around the distance of the Moon as I record this.

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Scott Tilley @coastal8049.bsky.social · 21d

IMAP on X-band. The spacecraft rotates as part of its design at 4 RPM (15s period). This is clearly visible as the periodic rotation of the antenna is summed onto the Doppler.

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Scott Tilley @coastal8049.bsky.social · 21d

TIANWEN-2 is presently in Canis Minor near Procyon. Chinese state media has reported that the mission will undergo a deep space maneuver on October 30th. 🛑

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Scott Tilley @coastal8049.bsky.social · 21d

TIANWEN-2 making a rare radio emission today.

The spacecraft is believed to be using solar electric propulsion and may need to change attitude to thrust and only aim at Earth for ranging and comms periodically. 🧵⬇️

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Scott Tilley @coastal8049.bsky.social · 21d

Checked in on CHANG'E 6 service module still in the vicinity of the Earth-Sun L2 Lagrange point.

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Scott Tilley @coastal8049.bsky.social · 21d

USA 310 continues to show a stable specular glint at ~50° phase, confirming reflection from a fixed surface over days.

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Scott Tilley @coastal8049.bsky.social · 21d

I have an UNID on S-Band at ~2258.1MHz in lock with something on the same beaming as SWFO-L1.

Most like the Carruthers Geocorona Observatory a cubesat launched with SWFO-L1 and IMAP.

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Scott Tilley @coastal8049.bsky.social · 21d

Space Weather Follow On - Lagrange 1 (SWFO-L1) found in lock with DSN Canberra and ranging.

Range is about 280000km from Earth on its way to the Earth-Moon L1.

I just found it as it was descending into the trees here.

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Scott Tilley @coastal8049.bsky.social · 24d

I have multiple instruments and it allows me to move things around.

Scott Tilley @coastal8049.bsky.social · 24d

The dome was getting a bit out of hand so did a big tidy, lubed and dressed all the cabling. Ready for a winter of on demand use.

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Scott Tilley @coastal8049.bsky.social · 25d

Given the repeating ground track (15/4) nature of USA 310's orbit and the optical light curve data my working hypothesis of its purpose is a MEO inSAR.

The goal of the mission may be to use SAR Interferometry to map deformations on a global basis to target LEO SAR missions. 🛑

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Scott Tilley @coastal8049.bsky.social · 25d

LACROSSE 5 an LEO SAR mission was studied carefully by @Marco_Langbroek
particularly it's 'disappearance trick', documented multiple times.

The Altai Optical Laser Centre and others have released hi-res images of LACROSSE 5. A large fixed planar structure was observed. ⬇️

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Scott Tilley @coastal8049.bsky.social · 25d

Comparing the two light curves gathered thus far confirms the qualitative observations from earlier amateur reports of a 'disappearance trick' similar to LACROSSE 5's.

USA 310 shows sharp, repeatable phase-angle flares. This points to fixed planar structure(s). ⬇️

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Scott Tilley @coastal8049.bsky.social · 25d

USA 310 continues to be the object of my focus as light curve data collection continues.

Due to high altitude ~11000km it's not possible to directly image. So we need to infer the shape of the spacecraft from light curve inversion techniques.

The data is tantalizing! 🧵⬇️

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Scott Tilley @coastal8049.bsky.social · 26d

Asteroid (112985) 2002 RS28 has a very inclined orbit and is presently near Polaris and is circumpolar in the Northern hemisphere presently.
🛑

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Scott Tilley @coastal8049.bsky.social · 26d

Near Earth asteroid (112985) 2002 RS28, a mere 0.548 AU away is tipping in with a 16.9mag brightness this night. This is about 20 minutes of 10s frames.
🧵⬇️

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Scott Tilley @coastal8049.bsky.social · 27d

In addition to the bright near Earth asteroid 1916 Boreas, I also noted:
17.5mag 30453 Cambioni,
17.6mag 8420 Angrogna, and
17.9mag 87302 2000 PV25.

Look hard and mark up if you can find them.😉

🛑

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Scott Tilley @coastal8049.bsky.social · 27d

While I was waiting for USA 310 last night I monitored the near Earth asteroid 1916 Boreas.🧵⬇️

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Scott Tilley @coastal8049.bsky.social · 27d

USA 310 light curve from this morning. I'm comparing relative flux to phase angle.

This behaviour has started me down a path of prolonged observation and study into light curve inversion. The dip at the end is tree extinguishment 😉

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Scott Tilley @coastal8049.bsky.social · 28d

USA 310's orbit has been accurately updated and now posted on the McCants classfd page.

I took a long look at it during a pass this morning and documented its 'almost disappearing trick' somewhat similar to LACROSSE 5's.

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Scott Tilley @coastal8049.bsky.social · 29d

USA 310 orbital analysis since launch.

The spacecraft maintains an orbit with a repeating ground track (RGT) of 15/4. To maintain this over the years the spacecraft must be performing small adjustments to maintain the RGT orbit.

Thus the RGT is a feature not a bug.

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Scott Tilley @coastal8049.bsky.social · Sep 16

USA 310 was recovered this morning in bright twilight.

This classified MEO mission is a bit of a mystery and was last seen by the unclassified world in 2023.

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