IC 4121

STARStar

ILLUSTRATION · NO MEASURED PROPERTIES

[

OVERVIEW

] STAR

IC 4121 is a star in the constellation Coma Berenices. It is catalogued as SDSS J130321.52+191656.2.

WHAT IT IS: Star
WHERE TO LOOK: Coma Berenices

[

OBSERVING

] FROM WHERE YOU ARE

What it takes to see IC 4121 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 IC 4121 is worth going out for.

VIEW IN SKY MAP

[

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 2026-08-28 00:00 UT. No proper motion is published for IC 4121, 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.

[

SPECTRUM

] ITS OWN LIGHT

A star gives out light at every wavelength at once. The dark gaps are atoms in the thin gas above its surface, each one removing the single colour it is able to absorb — which is how a list of ingredients is read off something nobody will ever touch.

MADE OF

Point at a labelled line — or an element above — to see which atom makes it and where it falls.

SDSS DR18 optical spectra · spec-2899-54568-0023 · observed 2008-04-12. SDSS fibre, 3 arcseconds across. Resolving power R = 1,500 to 2,500; 3,822 reduced pixels rebinned onto 1,019 log-spaced display points and normalised to the median flux. Brightness is scaled to this spectrum’s own middle value, so the shape is the measurement and the height is not. The 10 lines named above are the ones that stand clear of the scatter and of the features around them; a spectrum at this sampling holds many more that it cannot separate. The samples themselves, as JSON, CSV or VOTable.

[

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.

OTHER NAMES AND NUMBERS

The identifiers other catalogues file this object under, for anyone joining this data to theirs.

OpenNGC type code: *
Wikidata item: Q3684013

[

ALSO KNOWN AS

] 2 DESIGNATIONS

IC IC 4121
SDSS SDSS J130321.52+191656.2

[

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.

SIMBADIC 4121
Cross-identifications, measured values and the reference behind each of them.
ADSobject:"IC 4121"
Papers indexed against this object rather than against the string, newest first.
VizieR5″ around 195.8397 +19.2823
Every published table with a row at this position, searched by coordinates rather than by name.

[

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. IC 4121 [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/ic-4121

BIBTEX

@misc{spacecatalog_ic-4121,
  author       = {{SpaceCatalog}},
  title        = {{IC 4121}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/ic-4121},
  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from OpenNGC.}
}

The values above were taken from OpenNGC — CC-BY-SA-4.0. Citing this page does not replace citing that catalogue, and its licence is share-alike: the terms reach whatever you build from these rows.

[