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DEORBIT - Space Force just issued a decay notice for BlueBird 7, saying it reentered on Apr 20 (with no further details)

Well this is REALLY WEIRD. Space Force just issued another BB7 orbit with an epoch of 1235 UTC yesterday and a nominal orbit of 455 x 462 km x 49.5 deg. I suspect this orbit is BOGUS and is a `search orbit' not based on real measurements that slipped through by accident

The New Glenn second stage hasn't been cataloged yet , wondering where it is (possible what they are tracking is stage 2 and not the payload!)

A second orbit dataset from SpaceForce for the BlueBird-7 sat shows it in a 265 x 485 km x 43.0 deg orbit, indicating that the upper stage delivered about 1000 m/s, mostly changing orbital inclination. This is about half the dV that would have been needed for the target orbit

ASTS confirms unrecoverable failure but without any specific orbital parameters www.businesswire.com/news/home/20...

China's Daqi-2 satellite cataloged in a 682 x 689 km x 98.3 deg orbit in 1025 LTDN orbit plane. The Qianfan 07 orbits are now out, showing 800 x 820 km x 89.0 deg deployment orbits as expected.

LAUNCH at 1603 UTC Apr 19 of Starlink Group 17-22 from Vandenberg

The BlueOrigin/AST_SpaceMobile launch has been tracked by Space Force as catalog 68765, 2026-85A, in a 154 x 494 km x 36.1 deg orbit. Epoch is 1138 UTC which is the time of SECO-1, so this may not be the final orbit. (If it is, then they are indeed toast).

The next TLE set for this object, hopefully later today, will be definitive (absent any clarifying statement from Blue or ASTS). At this point we can still hold out some hope for a new orbit set at a later epoch time with a higher orbit. To be clear, I am not optimistic. But it's prudent to wait.

Best estimate for the SECO-1 orbit given the slow observed decrease in altitude in the webcast is somewhere in the range of 164 x 380 km to 116 x 420km, depending on flight path angle at cutoff which was somewhere in the 0 to -1 degree range. Still waiting for SECO-2 data.

LAUNCH at 1125 UTC Apr 19 of New Glenn flight 3 with AST SpaceMobile-007 from Canaveral. Second stage underperformance and lower than planned final orbit, but still waiting for Space Force tracking data for details

Astronauts Zhang L. and Wu F. made a spacewalk from the Chinese Space Station on Apr 16 from about 1206 UTC to 1736 UTC

LAUNCH at 0410 UTC Apr 17 of a CZ-4C from Jiuquan with the Daqi-2 atmospheric research satellite

LAUNCH at about 2318 UTC Apr 16 of one or more Kosmos satellites by Soyuz-2-1b from Plesetsk to a 457 x 547 km x 98.3 deg orbit

CelesTrak has 18 SDS GP data for 90 objects from the Transporter-16 mission, launched on Mar 30. We have set up a special GROUP to help those on this mission work to identify their satellites: celestrak.org/NORAD/elemen....

TEE-01B (2024-110A) sold by China's Mumei to the IRGC in 2024 Sep, according to the FT www.ft.com/content/1fdd...

Fascinating analysis of modern Ireland by Sinead O'Sullivan (who I know via her space policy work) www.butthistime.com/p/mind-the-gap

LAUNCH of Starlink Group 17-27 at 0429 UTC Apr 15 from Vandenberg Space Force Base

Starlink 34343 failed on Mar 29 in a fatal energetic event which raised its apogee by 30 km and generated observed (but so far uncataloged) debris. Since then the orbit has undergone natural decay. Current orbit is 547 x 574 km.

The Jilin-1 satellites launched last night have been cataloged in a 527 x 547 km x 97.6 deg orbit. Starlink Group 10-24 in 254 x 264 km x 53.2 deg orbit. XW Jishu Shiyan 8 in a 996 x 1008 km x 86.5 deg orbit with two objects in elliptical orbit (upper stage and adapter or two stages?)

Still no orbit data for Transporter-16 or the Qianfan launch

A more precise calculation gives a max CSS-Artemis distance as 419643 km at 2220:08 UTC; max ISS-Artemis was 419581 km at 2222:05 UTC. My earlier calculation neglected a coordinate frame precession between the Artemis and ISS/CSS data and used the 1 minute Horizons time grid without interpolation.

Ahh, I found the bug. D'oh, didn't calculate antipodal positions correctly. What I posted for Artemis and CSS was correct, but the sub-Artemis antipodes was actually over N Mexico at 107W 27N, which the CSS orbit (SW to NE here) crosses close to and the ISS track (NW to SE here) does not.

Earlier, I said the anti-Artemis point was over the Atlantic, where the ISS passes over more closely than the Chinese station, and I couldn't figure out why the Artemis-CSS distance came out larger. Now it all makes sense and I am confident of the earlier results.

I may come back with a slightly more accurate result later, the earlier data were based on the Horizons 1 minute time steps and I should be able to fit an osculating orbit and interpolate to get more like 1 second resolution. Stay tuned.

Cygnus NG-24 'S.S. Steven R. Nagel' has arrived at the ISS. The Canadarm 2 grappled the cargo ship at 1720 UTC Apr 13 and is preparing to berth it on the Unity module.

Artemis 2 was the furthest human voyage from Earth. Per the final JPL Horizons trajectory I estimate the max distance from the geocenter was 413145 km at 2304 UTC Apr 6 (about 4 km less and 1 min later than PAO's report at the time). (1 / n ).....

What about the crew of the ISS? At that moment, 2304 UTC Apr 6, they were on the same side of the Earth as the Moon and Artemis. So they were not the furthest from the Art crew at that moment. But.... (3/n)

Artemis's distance was changing pretty slowly for a couple of hours around apogee, during which the ISS was whizzing around the Earth. It turns out that 43 min earlier at 2221 UTC Apr 6, when ISS was passing over Kansas City, the ISS crew and the Artemis 2 crew were a record 419578 km apart.

Here is the reentry path of Starlink36340 as it burnt up over on Apr 10 about 0908 UTC

Starlink-36340, launched on Mar 14, failed early and reentered on Apr 10 near Heard Island

Confirmed the Jielong-3 launch, with a Xingwang test satellite

LAUNCH at 1141 UTC Apr 11 of a Falcon 9 from Canaveral with the ISS Cygnus NG-24 cargo ship SS Steven R. Nagel. Also waiting to confirm LAUNCH at 1133 UTC of a Jielong-3 from the Yanjiang area in the South China Sea

LAUNCH at 0504 UTC Apr 11 of Starlink Group 17-21 from Vandenberg Space Force Base

Three of the four Artemis II cubesats were meant to fire propulsion systems to raise perigee and stay in orbit. Only one (Saudi Arabia's SWC-1) managed to do so; TACHELES and K-RadCube reentered at first perigee.

One thing to think about is that this is the astronauts' first smell of Earth. Sea air and burning hydrocarbons. There's a breeze that they'll be feeling after days in a capsule. There are fans there, because without fans CO2 will build up around you. But not a breeze like off the ocean.

Artemis II mission duration 9d 1h 32m 15s

Updated Artemis II/Integrity landing time 0007:27 UTC, per NASA

Humanity did that. Science did that. Publicly-funded research did that. Excellent universities did that. Diversity did that. International cooperation did that. Artemis II is a perfect example of what we can do at our best. Welcome home, Integrity crew!

Glad to see the capsule is "Stable One". (There are two stable positions for a capsule after splashdown. "Stable Two" is NASA speak for "upside down".)

PAO reports splashdown time 0007:47 UTC, I get more like 0007:24 UTC

Integrity splashdown!

Integrity on chutes

Orion forward bay cover jettisoned, drogue chutes out

Three main chutes

All three mains fully inflated

AOS! Acquisition of Signal - getting data from Integrity after the blackout. And voice from the spacecraft! All ok

Reentry blackout underway, will last 6 minutes

Integrity begins the reentry phase at 2353 UTC at an altitude of 122 km

Integrity CM 3m/s raise burn using the small thrusters on the command module to ensure good distance from the abandoned service module

2333 UTC: the European Service Module has been jettisoned as Integrity approaches the atmosphere

Well, thanks Zoom for suddenly dying on me halfway through a live interview with CBC Canada.... sigh.

Artemis II carried out RTC3, the final course correction, at 1853 UTC. An 8 second, 1.3m/s delta-V burn. On course for entry at 2353 UTC and splashdown in the Pacific at 0007 UTC

5/x updated #Artemis II reentry trajectory map based on NASA event timeline and trajectory info, rather than JPL HORIZONS

Some confusion in the Artemis press conf about the issue with the helium pressurization system in the ESM oxidizer system. The issue is with an internal leak of helium here that is bigger than expected and could be a concern for later lunar orbiting missions. Also, ...

.. journalist seemed confused on this point: "oxidiser" is not the same as "oxygen"; some rockets use liquid oxygen as the oxidiser, but the Orion ESM uses N2O4 (nitrogen tetroxide) as the oxidiser.

The STP-S29A Minotaur IV payloads launched yesterday have been cataloged in 480 x 500 km x 60.0 deg orbits.

Today's space data plot: most reentry mass is from massive reentries. Plot show how much mass has reentered since 1957 in the form of 1-10 kg, 10-100 kg, etc, objects. Mostly 1 tonne class objects for deorbits and uncontrolled reentries, but 100 tonne class objects for landings (because Shuttle).

Apparently some are not familiar with the story: Croesus of Lydia asked the Oracle what would happen once he attacked Iran. Oracle predicted: "a great civilization will die". Of course it turned out that the one that died was Lydia, not Iran. Seems relevant...

LAUNCH of the US Space Force STP-S29A mission on a Minotaur IV from Vandenberg at 1133 UTC Apr 7

Anyone else getting strong Croesus-at-the-Oracle-of-Delphi vibes from this statement?

LAUNCH at 1332 UTC Apr 7 of a Chang Zheng 8 from Hainan with batch 4 of the commercial Qianfan internet satellite system - the first Qianfan launch since Oct 2025

Correction - this is batch 7 of Qianfan, according to the Chinese press.

China's Tianshi-1 appears to have been deployed from the Xinzhengcheng-02 parent satellite; object 66D was cataloged, but has TLEs that put it stationkeeping within 1 km of 66A. More data needed for clarity.

LAUNCH at 0249 UTC Apr 7 of Starlink Group 17-35 from Vandenberg

Integrity made its closest approach to the Moon, altitude 6543 km, at 2300:46 UTC Apr 6. Its furthest distance from Earth, 413149 km from the geocenter was at 2302:51 UTC.

Integrity has now passed lunar closest approach and is climbing uphill in the lunar gravity field. In about 18 hours it will leave the lunar gravitational sphere of influence and start falling back towards Earth.

I always assumed Mare Orientale was pronounced "Orient -tah - LAY", not "Orient- ahhl" as NASA is doing. Can any Latinists comment?

Some lunar vocabulary in case you're following along with the #Artemis II flyby: * albedo: reflectiveness (high albedo=very shiny) * mare/maria(plural): from Latin for "sea," dark regions on the Moon, which are dried lava basins * terminator: the line of the transition between sunlight & darkness

The Integrity spacecraft just entered the lunar gravitational sphere of influence, at 0438 UTC Apr 6. Wiseman, Glover, Koch and Hansen are now the 25th to 28th humans to have left terrestrial space.

Integrity made the 19-second OTC-3 course correction burn at 0303 UTC. (Two earlier OTC burns were cancelled as not needed)

I realize I failed to filter out some active deorbits so the curve will move up a bit when I fix this.

OK, I didn't miss many points so the curve didn't move noticeably. I think it's good as is.

Today's calculation: how long does a satellite in a circular orbit stay up when it stops all reboost burns? Depends on a lot of things, especially solar activity, but let's average over all of that and do a Kaplan-Meier analysis in 50 km height bins on 69 years of actual data.

This is for all payloads and rocket stages with end-of-active life orbit eccentricity < 0.05. The cyan lines are the 25 and 75 percentiles, the blue line is the median, and obviously above 70 years we only have lower limits because Sputnik wasn't that long ago.

For non-manueverable sats, the "post mission life" begins at launch.

Oh my gd, the Artemis II crew doing a parody of a bad 1980s sitcom intro from in space. Source: www.instagram.com/p/DWwuHPfCZ8Z/

👀 Behind the scenes tour of 's Eagle #Artemis II mission control room 🌙

The Artemis II cubesats TACHELES, SWC-1 and K-RADCUBE have now been identified on Space-Track. ATENEA was not cataloged, and was expected to have reentered at first perigee since it didn't have a propulsion system to raise its orbit. K-RADCUBE may also have reentered, and is reported to have failed

Space Force orbit data show the Meridian-M satellite launched yesterday in a 996 x 39714 km x 62.8 deg 'Molniya' orbit as expected

LAUNCH at 0546 UTC Apr 4 of a ULA Atlas V from Canaveral with the Amazon Leo LA-05 internet satellite cluster.

Three of the four Artemis-II cubesats have now been cataloged; orbits are 149 x 70247 km, 492 x 70228 km, and 61 x 70276 km. Suggests at least one made a successful perigee raising burn, but waiting for more data before drawing too many conclusions.

LAUNCH at 0628 UTC of a Soyuz-class rocket from Plesetsk. Suspected to be a Soyuz-2-1a/Fregat with a Meridian military comms satellite, but we'll have to wait for Space Force tracking to confirm that.

SpaceX and Amazon spar over satellite deployments Amazon says it will revise deployment plans for its broadband satellite constellation while denying claims from SpaceX that its current approach represents a space safety risk.

Apologies for the typo. 2306 UTC on Apr 1, ** 31 ** minutes after launch.

LAUNCH of Tianlong-3 from Jiuquan at about 0417 UTC. Speculation it has failed but no official info yet.

The crew aboard Integrity heading upwell

Per a question asked in the presser, Integrity's crew broke the Isaacman height record of 1400 km at 2306 UTC Apr 1, a mere 13 minutes after launch.

we can always count on you to ask the urgent questions

The IPCS stage should now have reentered over the Pacific Ocean east of Hawaii. No word yet on the status of the cubesats deployed from it

TLI! Translunar injection complete, Artemis II apogee now over 400,000 km; they're heading to the Moon.

TLI burn ignition!

The Artemis II Integrity spacecraft is now coasting downwards and will reach perigee of about 195 km late on Apr 2. At 2349:50 UTC it will make the TLI (Trans-Lunar Injection) burn, a 388 m/s burn lasting 5m51s to raise apogee to lunar distance.

At 1207 UTC, while near apogee, Integrity made a small (1 m/s?) perigee raise burn.

Hey, I wrote a thing about AI in astrophysics ergosphere.blog/posts/the-ma...

LAUNCH at 1115 UTC Apr 2 of Starlink Group 10-58 from Canaveral

You know, my scientific presentations aren’t always the best but I can say that none of my presentations tanked the global markets

Next major Artemis 2 milestone is a perigee-raise rocket burn carried out at 1130 UTC, near apogee. Resulting orbit will be around 191 x 70133 km.

Four cubesats (from Germany, S Korea, Argentina, and Saudi Arabia) were ejected from the ICPS stage at about 0405 UTC. Each cubesat will need to quickly make a perigee raising burn if they are not to reenter along with the ICPS, which seems a weird mission design choice.

The ICPS stage has now made a disposal burn and will reenter over the Pacific east of Hawaii sometime around 2330 UTC Apr 2.

Orion has made the USS2 burn to raise its perigee. ICPS remains in a 11 x 70358 km orbit; Orion now in a 118 x 70134 km orbit.

A 17th object has been cataloged associated with the Rassvet-3 launch. Not yet clear which of the 17 objects is the Soyuz upper stage.

Integrity will reach a 70385 km apogee at about 1200 UTC Apr 2, before falling back to perigee where it will make the rocket burn to send it moonward; that burn due at about 2345 UTC Apr 2.

Integrity is now using the ICPS upper stage as a target to practice stationkeeping and maneuvering, as part of this first crewed test flight of the Orion spaceship.

The Integrity spaceship has separated from the ICPS upper stage at 0157 UTC

LAUNCH at 2235:12 UTC of SLS flight 2 with Artemis 2 from Kennedy Space Center. Artemis 2 has now manuevered to a -2 x 70385 km x 28.3deg orbit

CREATE YOUR OWN GALACTIC CONSTELLATION!! the ever-brilliant really knocked the April fools paper bit out of the park with this incredible project. Nothing foolish here! #astronomy #STEAM #astroedu 🔭 cmlamman.github.io/galactic-con... 📃🔗 ⬇️

Between 1968 and 1972, twenty-four humans entered lunar space, where the Moon's gravity dominates that of the Earth (within about 66000 km from the selenocenter). Only five of them are still alive.