How it works

Ten gates, one question: what else could this be?

Skyptic runs the checks a professional would run first, in the order that kills most candidates earliest, and shows you the number behind every line. A candidate that gets through every gate is a survivor, and leaves with its report written for the right desk.

What a verdict means

Killed means something explains the candidate away, and it says what. Held means nothing killed it but one thing is still missing, and it says what. Survivor means every check that could run, passed. That makes it a candidate worth a desk's time, and the follow-up decides whether it is a discovery. You have done the work they would ask for first.

RWill the MPC read it?

Before anything else: are the rows in a form the Minor Planet Center will accept, and do they obey its basic reporting rules?

MOne moving body?

Do your rows lie on one straight, smoothly moving line, with your station's parallax allowed for? Rows from two or three different objects in the same field do not, and a chance link dies here.

SA star?

Gaia DR3 is asked about the place of every row, with proper motion carried to your date. A "mover" that sits on one fixed source is not moving.

AA satellite?

Orbital elements of about 28,000 satellites (CelesTrak, Project Pluto) are run forward with SGP4, from your station at your times, and compared with your place and your motion.

KAlready known?

The MPC's own orbit files, about 1.58 million orbits, are run to your times. If a catalogued body is where your rows are, moving the way they move, the candidate is a known object. IMCCE's SkyBoT can give a second opinion in the deep mode.

WAlready reported?

The MPC's WAMO is asked whether it already holds these rows.

OOne orbit?

With two or more nights, one orbit must fit every row. Two objects joined across nights do not fit one.

CCould it be an NEO?

The MPC's digest2 scores how likely an unidentified object is to be a near-Earth object. At 65 or more, the NEO Confirmation Page is the desk. This gate never kills: it decides where a survivor goes.

NJust noise?

Signal-to-noise of each row, and, for frames, a stacking test: each half of the frames alone must show the object, and a hundred stacks along wrong motions must not peak as high.

FCamera artefact?

For frames: a hot pixel, a cosmic ray or a trail shows up in the same pixel, or only in one frame, or with the wrong shape.

Two doors, the same checks

Privacy: what leaves, and when

Skyptic keeps nothing you send. To run its checks it asks four outside services about your rows: ESA's Gaia archive (is it a star), the MPC's WAMO (are these rows already reported), the IAU's SatChecker (is it a satellite) and, in the deep mode, IMCCE's SkyBoT (a second opinion on known objects). Tick Keep my rows private (or pass "private": true) and none of the four is asked. Everything runs on Skyptic's own copies of the catalogues, so the star check and the already-reported check are left out.

What it cannot do

The frames door is a beta: too few cases measured to trust it yet, and Measured shows the numbers. Skyptic can say an explanation was found. It cannot say that none exists beyond the catalogues it reads.

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