NASA Space Apps Planet X
Spot the movers in the

Sky

Since 2025, NASA’s SPHEREx mission has mapped the entire sky every six months in 102 bands of near-infrared light. Comets, asteroids, stars, brown dwarfs and even new planets give themselves away by shifting position between images. Enter a patch of sky, flip through the frames like a little video, and find what moves.

Click anywhere in space to spawn more star particles • Active Particles: 140
Explore ↓ Read the Challenge Brief

01 Challenge Briefing

Background, objectives and test targets for the Planet X and SPHEREx challenge.

02 How it works (real pipeline)

What actually happens to the SPHEREx data behind the real targets in this site.

  1. Query. Query the NASA/IPAC IRSA SIA service for SPHEREx DR1 and QR3 visits covering the target.
  2. Download. Download 7.5 arcmin cutouts centred on the target’s proper-motion-propagated position (Gaia DR3).
  3. Clean. Mask bad pixels from the flags extension and reproject every visit onto one north-up grid.
  4. Stack. Median-stack each survey pass (about 20 visits) and subtract passes after removing each pass’s background.
  5. Show. Show the passes as a blink and as difference images, with the expected motion arrow.

Source code: https://github.com/elsayedelmandoh/planetx-nasa26. Note: the deployed site is static; all processing runs offline in python and the results are served as files.

03 Pick your destination

Nine real SPHEREx gallery images with their published details, five challenge targets, and a viewer. Enter any RA/Dec, field of view (60″ to 6°) and date to open that patch of sky. Pixels are simulated; names, positions, dates and wavelengths are real.

Validation: the five challenge targets (computed from published positions and proper motions)

Want the science first? Walk through the Museum Halls.

04 Museum halls

Four short exhibitions explain the science behind this project. Each one is interactive and ends in the real tool that uses it.

05 Meet our team

Direct mission contacts, roles, and team leads.