IC 1795

NEBULAH II region

ILLUSTRATION FROM H II REGION · MAJOR AXIS 12′

[

OVERVIEW

] NEBULA

IC 1795 is an in the constellation Cassiopeia. It is catalogued as LBN 645 and LBN 133.80+01.10.

WHAT IT IS
H II region
HOW BIG ON THE SKY
12.0

About 0.4 of the full Moon's width.

WHERE TO LOOK
Cassiopeia

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

[

OBSERVING

] FROM WHERE YOU ARE

What it takes to see IC 1795 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 1795 is worth going out for.

[

THROUGH AN EYEPIECE

] 150 MM TELESCOPE · 25 MM EYEPIECE
NE
FIELD 1.08°

IC 1795 covers 12.0′ of sky against a of 1.08°, so at 48× it is comfortably framed.

48×
1.08
1.25
13.0
SIZE ON THE SKY
12.0
FILLS OF THE FIELD
18% of the width

IC 1795 is not a point of light, so the limit above is the wrong one to hold it against: the same brightness spread over 12.0′ of sky is harder than a star of it, and goes first. Catalogued sizes are measured to a photographic contour, and the part an eye sees is usually smaller.

FIND IT ON THE 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
16.0
PROPER MOTION SINCE
none published

Computed for 2026-08-27 00:00 UT. No proper motion is published for IC 1795, 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.

[

CATALOG DATA

] 6 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.

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.

Major axis
12
Minor axis
12

WHEN IT WAS FOUND

Who first saw it, from where, and by what method.

Discovered by
Edward Emerson Barnard

OTHER NAMES AND NUMBERS

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

OpenNGC type code
HII
Wikidata item
Q3146556
Wikipedia article
Fish Head Nebula
[

ALSO KNOWN AS

] 3 DESIGNATIONS
  • IC IC 1795
  • LBN LBN 645
  • Lynds LBN 133.80+01.10
[

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. IC 1795 [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/ic-1795
BIBTEX
@misc{spacecatalog_ic-1795,
  author       = {{SpaceCatalog}},
  title        = {{IC 1795}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/ic-1795},
  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.

[

RELATED OBJECTS

] 8 LINKED