Photograph of A0620-00, a stellar-mass black hole in Monoceros.

A0620-00

BLACK HOLEStellar-mass black hole
[

OVERVIEW

] BLACK HOLE

A0620-00 is a stellar-mass black hole in the constellation Monoceros, 3300 from Earth. Its mass is 6.60 . It was discovered in 1975.

The closest confirmed black hole to Earth, quietly orbiting with a small orange star that loops around it every 7.75 .

WHAT IT IS
Stellar-mass black hole
HOW FAR
3300

The light arriving now left it that long ago.

WHERE TO LOOK
Monoceros

The patch of sky it sits in, as seen from Earth.

[

THE MODEL

] SHADOW ONLY
OUTSIDE THE SURVEYED VOLUME · DRAG TO ORBIT

CALCULATED · NOT AN OBSERVATION · SCHWARZSCHILD RADIUS FROM THE MASS · 6.6 M☉ · ACCRETION QUIESCENT

The black disc is the shadow, 2.6 times wider than the horizon that casts it, and every ray in the frame is a null geodesic of the Schwarzschild metric. Nothing is falling in, so there is nothing else to see. Drag it, or use the arrow keys, to look from another direction. The stars behind are the 498,631 this catalogue holds real distances for, drawn from where the camera actually is — but every one of them is within 170 parsecs of the Sun and this object is much further out, so what is in the frame is that whole neighbourhood seen from outside it, piled into a knot around the Sun. The rest of the sky from here is not something this catalogue knows.

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IMAGES

] 1 FRAMES
  • Sloan Digital Sky Survey
    CC BY 4.0
[

OBSERVING

] FROM WHERE YOU ARE

What it takes to see A0620-00 for yourself. Everything in this part of the page is worked out for a real horizon, a real night and the equipment you say you have.

TONIGHT

Say where you are, and this line says when A0620-00 is worth going out for.

[

APPARENT PLACE

] EQUINOX J2026.7

Where a telescope has to be pointed today, which is not quite where the catalogue records the object: the coordinate grid itself has turned since the year 2000 the catalogue is referred to.

RIGHT ASCENSION
DECLINATION
GRID TURNED SINCE
20.6
PROPER MOTION SINCE
none published

Computed for 2026-08-27 00:00 UT. No proper motion is published for A0620-00, so nothing here moves the object; what separates this from the catalogued position above is the coordinate grid turning under it — about fifty arcseconds a year of precession since 2000, and the small nodding of the Earth’s axis on top of that. Aberration and refraction are not included, and neither is parallax; each is under an arcminute, which is also about as well as the catalogued position is known. The same figure for any date.

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CATALOG DATA

] 3 FIELDS

The raw catalogue values, as the source published them, with the error bars where one was published — sorted by what each set of figures is about rather than by the order they happened to be stored in.

WHAT IT IS MADE OF

What the object is in itself, rather than how it happens to look from here.

Accretion state
quiescent — between outbursts
Mass
6.6

WHERE IT IS AND HOW IT MOVES

Position, motion across the sky and the size it covers on it. These are measurements of the object as seen from here, so every one of them depends on where here is.

Accretion plane inclination
51
[

ALSO KNOWN AS

] 1 DESIGNATIONS
  • Common name A0620-00
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LOOK IT UP ELSEWHERE

] 3 SERVICES

Each link carries the identifier printed beside it. Nothing on this page is a measurement of our own, so a number that disagrees with one of these is worth reporting — and a service that has never catalogued this object under this name will say so plainly.

[

CITE THIS PAGE

] DR1

This page is live and its numbers move when an upstream refreshes, so the citation names the release the rows belong to rather than the day you read them. The release itself is frozen, republished as a bundle, and is what a data-availability statement should point at.

PLAIN TEXT
SpaceCatalog. A0620-00 [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/a0620-00
BIBTEX
@misc{spacecatalog_a0620-00,
  author       = {{SpaceCatalog}},
  title        = {{A0620-00}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/a0620-00},
  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from SpaceCatalog curated data.}
}

The values above were taken from SpaceCatalog curated data — CC-BY-4.0. Citing this page does not replace citing that catalogue.

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RECENT ACTIVITY

] 3 ITEMS

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