
Future astronaut, @Unistellar ambassador, exoplanet explorer, KBO co-discoverer, wannabe rocket scientist, occasional palaeontologist – boldly fighting entropy
In orbit around a G2V star
Joined December 2010
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Never miss a launch with #GoogleCalendar for worldwide space launches! Reminders & #webcast links included.
bit.ly/SpaceLaunchCalendar
Mario Billiani 🚀 retweeted
COSMOS 2612 (SSC.68762) walks up to ICEYE-X36 (SSC.59103)
In July we posted on the Cosmos 2609–2614 group. Back then we flagged COSMOS 2612 as the satellite best placed to reach ICEYE-X36. Three months later, it did.
Analysis via COMSPOC SSA.
On 1 October COSMOS 2612 raised its orbit ~47 km. The higher orbit gave it a fast catch-up drift, and it passed ICEYE-X36 at ~55 km on 5 October and again on 12 October. Within about two hours of the second pass it made two retrograde burns (~27 m/s total) and dropped back to ICEYE-X36’s altitude, ~515 km behind it. Between 13 and 16 October seven small burns (~5 m/s total) closed that gap.
By 16 October COSMOS 2612 was in ICEYE-X36’s plane (within 0.003°) and at its altitude. Since the two share a plane, there are no plane crossings to wait for. From 16–18 October they spent ~24 hours within 2 km of each other and ~12 hours within 1 km. First pass was ~220 m (max uncertainty ~490 m) near 14:03 UTC on 16 October. It then held 2–4 km behind before drawing level on 17 October and settling into a centred safety ellipse around ICEYE-X36, which it held for the rest of the day. Closest pass in our solution was ~60 m (max uncertainty ~950 m) near 14:18 UTC. By late on 17 October it had drifted ~2 km ahead, then trimmed back for a third pass at ~260 m (max uncertainty ~160 m) near 01:58 UTC on 18 October. Relative speed at the closest points was 0.15–0.9 m/s, walking pace or slower. Slow walk-past, not a fly-by . ICEYE-X36 did not maneuver.
COSMOS 2612 burned away at 12:30 UTC on 18 October, braked on 19 October, and is now holding ~480 km from ICEYE-X36 in the same orbit.
We’ve seen this sequence before. COSMOS 2581, 2582 and 2583 (SSC.62902/62903/62904) have been running it against each other since February 2025: raise, phase, drop to co-altitude, close at under half a meter per second, hold, depart, loiter. Since August 2025 we’ve logged more than 170 sub-km conjunction events within that trio, several down to single-digit meters. Until now, every target had been one of their own. This is the first non-cooperative one.
@planet4589
@shell_jim
@IntegrityISR
@ObservableSpace
Mario Billiani 🚀 retweeted
Before taikonauts fly onboard the Lanyue lunar lander, an uncrewed scientific cargo-carrying mission to the Moon's surface will take place using the spacecraft, probably in 2028
Details -> china-in-space.com/p/lanyue-…
Launch of @SpaceX #Falcon9 Block 5 rocket with 27 @Starlink satellites & 1st stage droneship landing imminent. Watch live!
xitter.cf/i/broadcasts/1qKDzWkEr…
Mario Billiani 🚀 retweeted
Never getting tired of watching this. The combination of a liquid kerosene core and four solid rocket boosters makes the Long March 6A’s "space jellyfish" completely unique.
Mario Billiani 🚀 retweeted
Back from France, catching up on analysis. The object found in Borneo on Oct 19 is indeed likely to be from the upper stage of ZQ-2E Y4, launched on Oct 14 and reentered on Oct 18. The ground track (using the final Space-Track TLE) passed near the debris site at 1036 UTC Oct 18.
Mario Billiani 🚀 retweeted
The dusk Long March 6A launch today painted a massive space jellyfish observable across northern China
Wow! This is from the CZ-6A launch with the Yaogan 50-03 spysat at 10:15 UTC today. The shot of the tumbling boosters in the wake of the ascending rocket is amazing.
Replying to @Cosmic_Penguin
Of course the separation of the 4 SRBs are also highly visible: m.weibo.cn/detail/5357253775…
Mario Billiani 🚀 retweeted
Multiple angles of the Long March 6A jellyfish as seen from airplanes: m.weibo.cn/detail/5357264317…
Mario Billiani 🚀 retweeted
A rare view of concerning activity in orbit.
From Oct. 16–18, a Russian satellite made several close approaches to a U.S. commercial satellite. This image, collected by Vantor’s WorldView Space capability on Oct. 17, shows Russian Cosmos 2612 at an estimated distance of about 1 km from ICEYE-X36.
“This image captures a reality long recognized by our national security leaders—space is becoming increasingly contested. Seeing one spacecraft repeatedly maneuver close to another raises serious concerns about capability and intent.”—Dan Smoot, Vantor CEO.
With WorldView Space, Vantor’s non-Earth imaging capability lets us collect images of other spacecraft in orbit, helping us better understand how they’re operating and spot activity that warrants a closer look.
Read @axios's exclusive coverage: axios.com/2026/10/22/space-w…
Explore WorldView Space: vantor.com/product/worldview…
Launch of @RocketLab #Electron rocket with three #Cluster16 @hawkeye360 satellites imminent. Watch live! #WereNotHawkingAround
xitter.cf/i/broadcasts/1nxnRBDNL…
Launch of @SpaceX #Falcon9 Block 5 rocket with 27 @Starlink satellites & 1st stage droneship landing imminent. Watch live!
xitter.cf/i/broadcasts/1YGNrbnzd…
Mario Billiani 🚀 retweeted
Replying to @tsr
Part 2 is enlightening as well. 👍
thespacereview.com/article/5…
Mario Billiani 🚀 retweeted
Russian companies have claimed to be operating radar-imaging satellites to fill gaps in limited Russian government systems. An examination of the links between these companies and China’s commercial space industry. thespacereview.com/article/5…
Mario Billiani 🚀 retweeted
It's been several months, but Galactic Energy's Ceres-1 is back with a sea launch near Rizhao earlier today, carrying a single remote sensing satellite to image Guangzhou and surrounding regions
Details -> china-in-space.com/p/guangzh…












