Research challenge · campaign

Planet Nine Mission Control

A rigorous search-coverage investigation — not a promise that SPHEREx will find Planet Nine. Test any predicted position against real SPHEREx observations.

Scientific boundary. Planet Nine has not been discovered and its current position is not established. Previous searches (for example Pan-STARRS1 combined with ZTF and DES analyses) have excluded a large fraction of specific reference-model parameter space, but not all models. SPHEREx observes at 0.75–5 µm, far from a cold distant planet's thermal peak, so geometric coverage is not detection.

Coverage checker · click the sky or enter a position

IRSA SIA · spherex_dr1

ecliptic (most proposed orbits lie near it) galactic plane (crowded, harder)

No positions checked yet. Click anywhere on the map or enter a predicted position from your chosen orbital model.

Ask the research assistant

The assistant can resolve positions, query SPHEREx coverage and explain detectability — using real tools, never inventing an orbit.

Search pipeline

Published orbital constraints & hypotheses

Mass, orbital elements, uncertainties

Orbital ensemble simulation

Sample many plausible orbits

Predicted sky-position distribution

RA/Dec density at each SPHEREx epoch

SPHEREx observation intersection

Real L2 footprints & timestamps — live below

Coverage & detectability

Observed · unobserved · inconclusive · detectable

Steps 1–3 need a chosen orbital model; bring positions from the literature. Step 4 runs live here.

Campaign

Claimed tiles

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Submissions

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Discuss in #planet-nine

Geometric coverage

Was the predicted position inside a real SPHEREx footprint at that observation time? The checker above answers this with live IRSA data.

Detection completeness

Given the model's predicted brightness, background, instrument response, noise and image quality, could it have been seen? That requires a sensitivity model — record your reasoning in a submission.

All missions