NGC 4809
ILLUSTRATION FROM HUBBLE TYPE IAB · SURFACE BRIGHTNESS 23.2 MAG/ARCSEC² · MAJOR AXIS 1.58′ · AXIS RATIO 0.41 · POSITION ANGLE 65°
OVERVIEW
] GALAXYNGC 4809 is an irregular galaxy IAB in the constellation Virgo, 60.94 from Earth, shining at apparent magnitude 13.78 (). It is catalogued as LEDA 43969, MCG +01-33-022 and PGC 43969, among 8 designations in total. It was discovered in 1855.
- WHAT IT IS
- Irregular galaxy
- HOW FAR
- 60.94
- HOW BIG ON THE SKY
- 1.6
- HOW BRIGHT (V)
The light arriving now left it that long ago.
Small enough that the full Moon would cover it several times over.
Faint: it takes a large telescope.
OBSERVING
] FROM WHERE YOU AREWhat it takes to see NGC 4809 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.
Say where you are, and this line says when NGC 4809 is worth going out for.
THROUGH AN EYEPIECE
] 150 MM TELESCOPE · 25 MM EYEPIECENear the faint end of this catalogue: a 300 mm telescope reaches it and a 150 mm one does not. NGC 4809 covers 1.6′ of sky against a of 1.08°, so at 48× it is a small patch, centred.
- 48×
- 1.08
- 1.25
- 13.0
- SIZE ON THE SKY
- 1.6
- FILLS OF THE FIELD
- 2% of the width
- APPARENT MAGNITUDE ()
- 13.78 · too faint for this
NGC 4809 is not a point of light, so the limit above is the wrong one to hold it against: the same brightness spread over 1.6′ of sky is harder than a star of it, and goes first — spread out, it comes to 23.2 . Catalogued sizes are measured to a photographic contour, and the part an eye sees is usually smaller.
APPARENT PLACE
] EQUINOX J2026.7Where 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
- 22.3
- PROPER MOTION SINCE
- none published
Computed for 2026-08-27 00:00 UT. No proper motion is published for NGC 4809, 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 LIGHTA galaxy's spectrum is every star in it added together, so the gaps are the ones its commonest stars make. Where a line comes back as a spike instead, gas somewhere in the galaxy is being lit hard enough to glow on its own.
Point at a labelled line — or an element above — to see which atom makes it and where it falls.
- SHIFTED Every line above sits 0.3% redder than the wavelength its atom emits at, because NGC 4809 is receding. The pattern survives it — the whole barcode slides together, which is how the shift is measured in the first place.
- NOT THE OBJECT The dip marked O₂ A band near 762 is oxygen in the air above the telescope, absorbing on the way in. It is in the measurement and it is not in NGC 4809, so it gets no chip.
SDSS DR18 optical spectra · spec-0523-52026-0480 · observed 2001-04-27. SDSS fibre, 3 arcseconds across. Resolving power R = 1,500 to 2,500; 3,838 reduced pixels rebinned onto 1,022 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
] 13 FIELDSThe 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.
- Hubble type
HOW BRIGHT IT IS
What the light adds up to, measured through one filter at a time. A magnitude is a brightness on a backwards scale — the smaller the number, the brighter the object.
- Apparent magnitude ()
- Apparent magnitude ()
- Surface brightness
- 23.23
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.
- Radial velocity
- 973
- Redshift (z)
- Redshift (z, CMB frame)
- Major axis
- 1.58
- Minor axis
- 0.64
- 65
WHEN IT WAS FOUND
Who first saw it, from where, and by what method.
- Discovered by
- William Parsons, 3rd Earl of Rosse
OTHER NAMES AND NUMBERS
The identifiers other catalogues file this object under, for anyone joining this data to theirs.
- OpenNGC type code
- G
- Wikidata item
- Q1114474
ALSO KNOWN AS
] 8 DESIGNATIONS- LEDA LEDA 43969
- MCG MCG +01-33-022
- NGC NGC 4809
- PGC PGC 43969
- SDSS SDSS J125451.06+023914.7
- SDSS SDSS J125451.07+023914.7
- SDSS SDSS J125451.12+023914.7
- UGC UGC 8034
LOOK IT UP ELSEWHERE
] 4 SERVICESEach 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.
- SIMBADNGC 4809
Cross-identifications, measured values and the reference behind each of them.
- NEDNGC 4809
Redshift-independent distances, photometry across the spectrum and the extragalactic literature.
- ADSobject:"NGC 4809"
Papers indexed against this object rather than against the string, newest first.
- VizieR47″ around 193.7127 +2.6541
Every published table with a row at this position, searched by coordinates rather than by name.
CITE THIS PAGE
] DR1This 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.
SpaceCatalog. NGC 4809 [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/ngc-4809
@misc{spacecatalog_ngc-4809,
author = {{SpaceCatalog}},
title = {{NGC 4809}},
howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
year = {2026},
url = {https://spacecatalog.org/object/ngc-4809},
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.