Michael BuschMar 3

Today on the #arXiv :

Deen & Lam 2026, "2024 YR4: Identification of Possible Precoveries in 2016 IPTF Data" - https://arxiv.org/abs/2603.00449

This paper presents an archival search of old telescope images of #2024YR4 . It just happened to fall in gaps of several surveys.

But Deen & Lam identify one marginal potential detection from Palomar in 2016. If real, it would exclude the potential lunar impact in 2032.

I await the results of the latest JWST observations, which should be far clearer.

2024 YR4: Identification of Possible Precoveries in 2016 IPTF Data

2024 YR4 is a 40-100 meter-diameter asteroid and former Torino Scale 3 object which currently has a roughly 4% chance of impacting the Moon on 2032 December 22, an event which recent studies suggest could pose a hazard on Earth due to impact ejecta. We present a search for, and identification of, potential precovery observations of the virtual lunar impactor in Intermediate Palomar Transient Facility (IPTF) survey data, as well as other publicly accessible surveys, dating from 2016. These candidate detections, not accounting for any currently-undetected Yarkovsky forces, predict a perilune of 22001 +/- 49 km and a perigee of 277534 +/- 46 km (relative to the center of each respective body) representing an improvement of > 300 times in the approach distance uncertainty above the existing orbit solution and, if confirmed, decisively ruling out a lunar impact in 2032. Using a matched filter tuned to 2024 YR4's predicted appearance in each image, we find the detection to be significant at Pnull = 5x10-9. The resultant possible orbit solution should be easy to confirm during 2024 YR4's 2028 approach to Earth, potentially greatly reducing the effort required by the planetary defense community at large to characterize 2024 YR4 before its potential lunar impact.

arXiv.org
Show threadMichael Busch
Additional discussion at https://groups.io/g/mpml/topic/2024_yr4_found_in_2016_iptf/118107365
Mar 3 at 5:07amWeb
Show threadMichael BuschMar 5

JWST confirms that #2024YR4 will miss the Moon in 2032.

And apparently also confirming that the potential precovery observation was indeed in the right spot.

https://science.nasa.gov/blogs/planetary-defense/2026/03/05/new-nasa-asteroid-observations-eliminate-chance-of-2032-lunar-impact/

2024 YR4 will not come so close to Earth and Moon again until at least the mid-2050s.

But its orbit will still have a very low minimum distance from Earth's.

For a longer-term trajectory prediction; wait until after the 2032 flyby.

New NASA Asteroid Observations Eliminate Chance of 2032 Lunar Impact

Using data from NASA’s James Webb Space Telescope observations collected on Feb. 18 and 26, experts from NASA’s Center for Near-Earth Object Studies at the

NASA Science
Show threadMichael BuschMar 5

A lot of people seem to have really wanted 2024 YR4 to impact the Moon.

There will be other impactors.

Show threadGeoff 🏴󠁧󠁢󠁳󠁣󠁴󠁿Mar 5
@michael_w_busch No light show, boo! ;)
Show threadMichael BuschMar 5

@_thegeoff

For now.

It will come back eventually (with no guarantee of impact when it does, of course).