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From The Decisional Pass

In February, the Swift team turned their telescopes off. Nothing was broken. A telescope pointed into the wind is a sail, Swift was falling, and every bit of drag they took off the vehicle bought days.

Last Wednesday they turned them back on.

The thing they were saving it for

Swift launched in November 2004 and has been the fast-reflex instrument of high-energy astronomy ever since. It detects a gamma-ray burst with one telescope, works out where it came from, and slews the other two onto it in less than about 90 seconds, all by itself, with nobody on the ground in the loop. It finds roughly 100 bursts a year, and had passed 1,400 by its fifteenth.

The problem was never the spacecraft. It's the air. Solar activity heated and puffed up the upper atmosphere, drag went up with it, and Swift's orbit came down faster than the models said. By August it was circling at 343 to 347 km.

In September 2025 NASA tried something nobody had done. It gave Katalyst Space $30 million and about a year to build a spacecraft, fly it to Swift, grab a vehicle that was never designed to be grabbed, and haul it up to roughly 600 km. That spacecraft, LINK, launched on July 3 aboard a Pegasus XL.

Around July 25, LINK lost attitude control and began to tumble. The team worked it for three weeks. They brought the spin down from 9 degrees per second to 1.47, uploaded new attitude controllers in mid-August, and still came up short: two of three reaction wheels gone, the cold gas thrusters only partly working. On August 19, NASA and Katalyst said the boost wasn't happening.

Worth being careful here, because it's easy to read a failed mission as a failed idea. Nobody has ever docked a commercial vehicle to a government spacecraft that wasn't built to be docked with. Katalyst is still flying LINK around Swift doing rendezvous and proximity operations, which is the part of the problem you can still learn from.

Spending it down

Here's the decision I keep turning over.

Once the boost was off, the whole calculation inverted. Drag stopped mattering, because there was no longer anything to protect it for. So on August 26, the team powered the Ultraviolet/Optical Telescope and the X-ray Telescope back up. The Burst Alert Telescope, off since April to save power, is being brought back over the next few weeks.

Swift has to stay above about 300 km to point and work. NASA expects it to sink through that in one to two months, and to reenter later this year.

So it's a spacecraft doing science on a stopwatch. Every burst it catches between now and then exists because somebody decided the last few weeks were worth more as data than as altitude. That's an operations call, and I think it's the right one.

Found in a file drawer

A different kind of clock.

On August 25, a team led by Takafumi Ootsubo published a comet nobody went looking for. Comet 28P/Neujmin was sitting in public archive images from Subaru's Hyper Suprime-Cam, taken for a survey that had nothing to do with comets.

It was more than 10 AU out, past Saturn's distance, cold and quiet with no coma. And by luck it had been caught at a phase angle of 0.33 degrees, with the Sun, the comet and Earth almost perfectly lined up. That's the geometry where a surface brightens sharply, and it gave the first clear ground-based measurement of that opposition surge on a bare cometary nucleus.

The result is the good part. In colour and reflectance, 28P looks like a dark, reddish asteroid. But it brightens like a bright one, which says the microstructure of its surface isn't asteroid-like at all. The team's reading is that repeated passes near the Sun, with ice sublimating off over and over, slowly built a texture you don't get anywhere else.

Nobody proposed that observation. It was already paid for.

The other clock

One more, same week. Naman Bajaj and Uma Gorti went through 72 young Sun-like stars in archival JWST MIRI data, looking at the gas leaving their planet-forming disks.

They found molecular hydrogen and ionised neon in 66 of them: cone-shaped molecular winds in 46, fast neon jets in 40. Line the disks up by age and they tell a story. Young ones drive strong, magnetically launched winds. Older ones shift toward photoevaporation, starlight simply boiling the gas away.

Either way, the gas goes. Which sets a deadline. A Jupiter has to finish drinking its atmosphere while there's still a disk left to drink from. Miss that window and you get a smaller planet, permanently.

Three stories, one shape. Swift has weeks. Those disks had a few million years. And somewhere in a public archive, a comet sat waiting for somebody to notice it was in the frame.

References

• NASA's Swift Restarts Science Observations — NASA Science, 28 August 2026
• NASA Updates Next Steps for Commercial Swift Boost Mission — NASA Science, 19 August 2026
• Katalyst Space and NASA abandon plans for Swift reboost — Jeff Foust, SpaceNews, 19 August 2026
• About the Swift Gamma-Ray Burst Mission — NASA Goddard Space Flight Center
• Subaru Telescope Archive Data Reveal Unexpected Surface Properties of a Comet — Subaru Telescope, 25 August 2026
• Naked Photo-Bombing Comet Found in Public Image — NAOJ, 25 August 2026
• JWST Reveals a Race Against Time for Forming Planets — SETI Institute, 25 August 2026
• JWST/MIRI Reveals the Evolution from Molecular to Atomic Disk Winds — Bajaj et al., The Astronomical Journal

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