---
title: "NGC 2491"
url: "https://spacecatalog.org/object/ngc-2491"
release: "DR1"
licence: "CC-BY-SA-4.0"
citation: "SpaceCatalog. NGC 2491 [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/ngc-2491"
---

# NGC 2491

NGC 2491 is a [galaxy](https://spacecatalog.org/galaxies) in the constellation [Canis Minor](https://spacecatalog.org/constellation/canis-minor), 944.1 Mly from Earth, shining at apparent magnitude 15.90 (B). Other catalogues list it as 2MASX J07582739+0759018, LEDA 22353 and PGC 22353, among 5 designations in total. It was discovered in 1885.

## At a glance

- **WHAT IT IS:** Galaxy
- **HOW FAR:** 944.1 Mly — A luminosity distance, from its redshift — how faint it looks. The light itself left 849 million years ago.
- **HOW BIG ON THE SKY:** 41″ — Small enough that the full Moon would cover it several times over.
- **HOW BRIGHT (B):** 15.90 — Faint: it takes a large telescope.
- **WHERE TO LOOK:** [Canis Minor](https://spacecatalog.org/constellation/canis-minor) — The patch of sky it sits in, as seen from Earth.

## Properties

| Quantity | Value |
| --- | --- |
| CLASS | Galaxy |
| DISTANCE FROM EARTH | 944.1 Mly ±41 — by redshift (CMB frame), flat ΛCDM with H0 = 70 km/s/Mpc |
| APPARENT MAGNITUDE (B) | 15.90 |
| CONSTELLATION | Canis Minor |
| RIGHT ASCENSION (J2000) | 07h 58m 27.4s |
| DECLINATION (J2000) | +07° 59′ 01.7″ |
| DISCOVERED | 1885 |

## Catalogue data

### 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.

| Field | Value |
| --- | --- |
| Apparent magnitude (B) | 15.90 |
| Apparent magnitude (J) | 12.86 |
| Apparent magnitude (H band) | 12.18 |
| Apparent magnitude (K) | 12.05 |
| Surface brightness | 23.79 mag/arcsec² |

### 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.

| Field | Value |
| --- | --- |
| Radial velocity | 18 476 km/s |
| Redshift (z) | 0.06365 |
| Redshift (z, CMB frame) | 0.0644855 |
| Major axis | 0.69′ |
| Minor axis | 0.53′ |
| Position angle | 78° |

### WHEN IT WAS FOUND

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

| Field | Value |
| --- | --- |
| Discovered by | Lewis A. Swift |

### OTHER NAMES AND NUMBERS

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

| Field | Value |
| --- | --- |
| OpenNGC type code | G |
| Wikidata item | Q1049365 |
| Wikipedia article | NGC 2491 |

## Also known as

- 2MASX: 2MASX J07582739+0759018
- LEDA: LEDA 22353
- NGC: NGC 2491
- PGC: PGC 22353
- SDSS: SDSS J075827.37+075901.7

## Source

[OpenNGC](https://github.com/mattiaverga/OpenNGC) — CC-BY-SA-4.0

The producer asks: OpenNGC, Mattia Verga (github.com/mattiaverga/OpenNGC). Fields derived from it stay under CC BY-SA 4.0.

How this was made: https://spacecatalog.org/methods#source-openngc

## Cite this page

SpaceCatalog. NGC 2491 \[catalogue entry\]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/ngc-2491

```bibtex
@misc{spacecatalog_ngc-2491,
  author       = {{SpaceCatalog}},
  title        = {{NGC 2491}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/ngc-2491},
  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from OpenNGC.}
}
```

OpenNGC — CC-BY-SA-4.0

Acknowledgement the producer asks for: OpenNGC, Mattia Verga (github.com/mattiaverga/OpenNGC). Fields derived from it stay under CC BY-SA 4.0.

The page itself, with its pictures, the sky map and the observing tools: https://spacecatalog.org/object/ngc-2491