NASA SPHEREx · moving-object search · Planet X
Everything that moves
in the infrared sky.
Driftnet searches real images from NASA's SPHEREx space telescope for objects that move between observations: asteroids, comets and distant bodies in the outer solar system. Every one is tracked, checked against JPL's catalog of known objects, and published with the evidence for and against it.
- SPHEREx images analyzed
- 333,456
- patches of sky searched
- 19,302
- of sky covered (2.7%)
- 1129.5 deg²
- moving objects tracked
- 706
Survey data as of Nov 13, 2026.
New here? How to use this site
Watch something move
Open a patch of sky and press Blink: stars hold still, moving objects jump.
Pick a patchRead the evidence
Every object has one report: is it a known asteroid, and could it be a glitch?
Browse objectsSee what's still unexplained
The objects JPL hasn't identified yet, ranked, and where in the sky we haven't looked yet.
Unexplained leads
What it does
A transparent search for moving objects, built on real data
Moving objects reveal themselves by shifting against the fixed stars. SPHEREx photographs each part of the sky again and again, in 102 infrared colors, which makes its archive a natural place to look. We turn those images into a searchable, checkable record of what moved.
- Find
Moving-object detection in real survey data
We process SPHEREx Level 2 images from NASA's public archive, measure every source in every exposure, discard what stays fixed to the sky, and link the sightings that move consistently into tracks.
- Verify
Every track checked against known objects
Each track is compared with JPL's catalog of known asteroids and comets for the exact time and place of each image. Matches are labelled as known; anything left over is reported as unexplained, never as a discovery.
- Explain
Evidence you can audit
Every object gets a report with its measured positions, motion fit, signal quality, the ways it could be wrong, and a link from every image to the exact archive file it came from. AI-written summaries are checked number by number against the measurements.
How it works
From raw images to an evidence report
A Python pipeline in GitHub Actions searches new patches of sky several times a day and checks every new track against JPL's catalogs before it is published. Tracks JPL couldn't explain are re-checked on a schedule, so labels can change as catalogs grow.
What SPHEREx sees
0.75 to 5 µm, invisible to our eyes. Each detector's filter changes color from edge to edge, so one object can look brighter or fainter from one visit to the next.
Ingest
SPHEREx Level 2 images for each patch of sky, fetched from NASA/IPAC's public SPHEREx archive with their observation IDs, times and wavelengths.
Detect
Sources are measured in every exposure. Pixels the instrument flags as unreliable are tracked, so a detector glitch can't pass as a sighting.
Remove the fixed sky
Stars and galaxies sit in the same place on every date. Sources that stay put are set aside; what's left are sightings that might be moving.
Link and fit
Sightings from different exposures are linked into tracks that move at a steady rate and direction, and the motion is fitted, including the shift from SPHEREx's own movement around Earth.
Check against JPL
The pipeline asks JPL's small-body services (SBIdent, then Horizons) which known asteroids and comets were at each position at each time, as seen from SPHEREx. Matches are labelled known; tracks JPL can't explain stay Unexplained and are re-checked on a schedule.
Score and publish
Vetting checks and a rule-based score rank each track. Simulated objects planted in real images measure how faint and how slow an object we can actually recover.
Where we've looked so far
19,302 patches of sky searched, 642 of them with something that moved. Most of the search follows the ecliptic, the band where the planets travel and where a distant planet would most likely be.
Ways in
See it for yourself
Not yet identified by JPL
The objects JPL hasn't matched to a known asteroid or comet (some are still being checked, some may be glitches), ranked by the strength of the evidence, each with a blink, the case for and against, and where to point a telescope to confirm it.
See the leadsPatches of skyBlink the sky
Pick a patch of sky and flip between real SPHEREx images taken hours or days apart. Stars hold still; movers jump.
Start exploringObjectsWeigh the evidence
Every moving object in one searchable list. Each has one report: its images, positions, speed, signal quality, the JPL check, the explanations we can and can't rule out, and, once fitted, its orbit and distance.
Browse objectsSky mapWhere we've searched
Every patch of sky we've processed on one all-sky map, with the ecliptic and the Milky Way for reference.
Open the mapDetection limitsWhat we could miss
How faint and how slow an object we can recover, measured by planting simulated objects in real images.
See the limitsStart here
Patches of sky to explore
Scientific integrity
We're looking, not claiming.
Scientists have proposed that an undiscovered planet, often called Planet X or Planet Nine, may orbit far beyond Neptune. That question is why we built this, but we have not found it. When a moving object doesn't match anything known, it could be an image artifact, a measurement error, or a real object no catalog lists yet. We publish the evidence and say which explanations we can and can't rule out.
See where Planet X could still be hiding, and how we test ourselves