Cloverleaf quasar

BLACK HOLEQuasar

LENSED · SCHWARZSCHILD FROM ACCRETION QUASAR · INCLINATION NOT MEASURED

[

OVERVIEW

] BLACK HOLE

Cloverleaf quasar is a in the constellation Boötes, 66.23 from Earth. Other catalogues list it as H1413+117. It was discovered in 1988.

Lensing splits it into four images arranged like a clover. It was the first quasar found to contain carbon monoxide, which established that the cold molecular gas galaxies build stars out of was already in place ten billion years ago.

WHAT IT IS
Quasar
HOW FAR
66.23

A luminosity distance, from its redshift — how faint it looks. The light itself left 10.8 billion years ago.

WHERE TO LOOK
Boötes

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

[

OBSERVING

] FROM WHERE YOU ARE

What it takes to see Cloverleaf quasar 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 Cloverleaf quasar 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
20.7
PROPER MOTION SINCE
none published

Computed for 2026-09-03 00:00 UT. No proper motion is published for Cloverleaf quasar, 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

] 2 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 KIND OF THING IT IS

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

Accretion state
quasar — a thin disc near its Eddington limit

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.

Redshift (z)
[

ALSO KNOWN AS

] 2 DESIGNATIONS
  • Common name Cloverleaf quasar
  • Common name H1413+117
[

LOOK IT UP ELSEWHERE

] 1 SERVICE

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. Cloverleaf quasar [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/cloverleaf-quasar
BIBTEX
@misc{spacecatalog_cloverleaf-quasar,
  author       = {{SpaceCatalog}},
  title        = {{Cloverleaf quasar}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/cloverleaf-quasar},
  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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