---
title: "NGC 6591"
url: "https://spacecatalog.org/object/ngc-6591"
release: "DR1"
licence: "CC-BY-SA-4.0"
citation: "SpaceCatalog. NGC 6591 [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/ngc-6591"
---

# NGC 6591

NGC 6591 is a [galaxy](https://spacecatalog.org/galaxies) in the constellation [Hercules](https://spacecatalog.org/constellation/hercules), shining at apparent magnitude 16.39 (B). Other catalogues list it as 2MASX J18140377+2103505, LEDA 61610 and PGC 61610. It was discovered in 1864.

## At a glance

- **WHAT IT IS:** Galaxy
- **HOW BIG ON THE SKY:** 32″ — Small enough that the full Moon would cover it several times over.
- **HOW BRIGHT (B):** 16.39 — Faint: it takes a large telescope.
- **WHERE TO LOOK:** [Hercules](https://spacecatalog.org/constellation/hercules) — The patch of sky it sits in, as seen from Earth.

## Properties

| Quantity | Value |
| --- | --- |
| CLASS | Galaxy |
| APPARENT MAGNITUDE (B) | 16.39 |
| CONSTELLATION | Hercules |
| RIGHT ASCENSION (J2000) | 18h 14m 03.9s |
| DECLINATION (J2000) | +21° 03′ 50.0″ |
| DISCOVERED | 1864 |

## 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) | 16.39 |
| Surface brightness | 23.78 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 |
| --- | --- |
| Major axis | 0.54′ |
| Minor axis | 0.21′ |
| Position angle | 54° |

### WHEN IT WAS FOUND

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

| Field | Value |
| --- | --- |
| Discovered by | Albert Marth |

### 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 | Q1146617 |

## Also known as

- 2MASX: 2MASX J18140377+2103505
- LEDA: LEDA 61610
- NGC: NGC 6591
- PGC: PGC 61610

## 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 6591 \[catalogue entry\]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/ngc-6591

```bibtex
@misc{spacecatalog_ngc-6591,
  author       = {{SpaceCatalog}},
  title        = {{NGC 6591}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/ngc-6591},
  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-6591