Jonathan McDowell
@planet4589
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Astronomer commenting on space launches. Orbital Police. Personal account. All plots CC-BY. @planet4589 on Ma, bsky, etc.
Somerville, MA, USA
Joined January 2009
This was the 300th Falcon 9 launch to carry Starlink satellites.
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LAUNCH at 0351 UTC Sep 3 of Starlink group 17-8 from Vandenberg.
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Some of the satellite reentries in the past week that are not yet reflected in Space-Track because of the ongoing problems: Flock 4y-25, YAM-2, Jilin-1GF03D17, Hawk 4A/4B/4C, OSM-1 CICERO, OHS-3A.
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LAUNCH at 1930 UTC Sep 2 of a Shaviyt from Palmachim AFB, Israel carrying the 'Ofeq-19 ( אופק 19 ) radar spy sat into a circa 140 deg retrograde low Earth orbit.
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The Skykraft 4 satellites from the TRACERS launch have now been cataloged in 590 km orbits; however the Space Force orbit data for SKYKRAFT 4B (64896) are spurious - they show it in a geotransfer orbit that must actually belong to an Ariane stage fragment.
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LAUNCH at 1149 UTC Aug 31 of Starlink Group 10-14 from Canaveral.
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At Reagan. It’s now every time you fly. Delayed. Claiming maintenance issues. It’s every time.
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LAUNCH at 0459 UTC Aug 30 of Starlink Group 17-7 from Vandenberg Space Force Base.
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I talk to the Bulletin of the Atomic Scientists (the keepers of the famous doomsday clock).
Astronomer and astrophysicist Jonathan McDowell @planet4589 describes some of the many ways in which international friction—and even war—could begin in orbit. This Bulletin magazine article is available to all readers for a limited time.
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The @AST_SpaceMobile SM005 and SM001's Space Force tracking data put them occasionally within 20 km of each other, possibly just a tracking mistake and the satellites are being confused with each other? Or deliberate close approach experiments?
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Here is a snapshot of the sat positions at 0h UTC today, note that two of them (SM005 and SM001) are close to each other
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The five large @AST_SpaceMobile BlueBird comm sats were launched in 2024; time to take a look at their orbits. After ejecting their antenna covers in October (magenta lines) the main sats (blue) decreased drag, controlled at the same height but at 10000 km spacings
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Blazing-fast image creation – using just your voice. Try Grok Imagine.
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RT @AJ_FI: Which country returns astronauts to the Moon first this century will be fascinating to watch. But note that only one side frames….
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TOMEX artificial ionospheric clouds mapping out upper atmosphere structure.
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@NASAWallops Correction: planneed apogees were 154 km for the Terrier Orions and 135 km for the Black Brant 9.
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LAUNCH at 0248:30 UTC Aug 28 from @NASAWallops LA2 50K launcher of suborbital TOMEX+ Black Brant 9 flight NASA 36.335CE to circa 250? km apogee.
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LAUNCH at 0244:00 UTC Aug 28 from @NASAWallops LA2 MRL launcher of suborbital TOMEX+ Terrier-Improved Orion flight NASA 41.124CE to circa 100 km apogee.
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I covered Rises the Moon, a song that feels like being held when you’re breaking. I didn’t know how much I needed it until I sang it—a tender cover for anyone seeking comfort and healing. FOLLOW for more great vibes!
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