---
title: "ET UMa"
url: "https://spacecatalog.org/object/hd-89822"
release: "DR1"
licence: "CC-BY-SA-4.0"
citation: "SpaceCatalog. ET UMa [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/hd-89822"
---

# ET UMa

ET UMa is an A1:VpSiSrHg white main-sequence [star](https://spacecatalog.org/stars) in the constellation [Ursa Major](https://spacecatalog.org/constellation/ursa-major), 339.4 ly from Earth, shining at apparent magnitude 4.94 (V). Other catalogues list it as GJ 9327, HD 89822 and HIP 50933, among 5 designations in total.

## At a glance

- **WHAT IT IS:** White main-sequence star
- **HOW FAR:** 339.4 ly — The light arriving now left it that long ago.
- **HOW BRIGHT (V):** 4.94 — Bright enough for the naked eye, under a sky dark enough.
- **WHERE TO LOOK:** [Ursa Major](https://spacecatalog.org/constellation/ursa-major) — The patch of sky it sits in, as seen from Earth.

## Properties

| Quantity | Value |
| --- | --- |
| CLASS | A1:VpSiSrHg white main-sequence star |
| MASS | 3.02 M☉ — Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4) — low confidence: above 7,500 K GSP-Phot's temperature and extinction are degenerate |
| DISTANCE FROM EARTH | 339.4 ly — by parallax |
| APPARENT MAGNITUDE (V) | 4.94 |
| ABSOLUTE MAGNITUDE (V) | −0.15 |
| CONSTELLATION | Ursa Major |
| RIGHT ASCENSION (J2000) | 10h 24m 07.9s |
| DECLINATION (J2000) | +65° 33′ 59.1″ |

## Catalogue data

### WHAT KIND OF THING IT IS

What the object is in itself, rather than how it happens to look from here.

| Field | Value |
| --- | --- |
| Spectral type | A1:VpSiSrHg |
| Surface temperature | 10 276 K |
| Luminosity (visual) | 99.6323 L☉ |
| Luminosity (bolometric) | 131.7061 L☉ |
| Radius | 3.904 R☉ |
| Mass | 3.018 M☉ |
| Surface gravity (log g) | 3.676 |
| Metallicity (\[Fe/H\]) | 0.13 ±0.025 |
| Age | 3.01×10⁸ years |
| Variability | Alpha-2 Canum Venaticorum magnetic rotating variable |
| Variability type (GCVS) | ACV |

### 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 |
| --- | --- |
| Colour index (B−V) | −0.052 |
| Variable magnitude, brightest | 4.93 |
| Variable magnitude, faintest | 4.95 |

### 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 |
| --- | --- |
| Proper motion (RA) | −8.93 mas/yr |
| Proper motion (Dec) | −20.83 mas/yr |
| Radial velocity | −2.6 km/s |

### OTHER NAMES AND NUMBERS

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

| Field | Value |
| --- | --- |
| Variable-star designation | ET UMa |

### WHERE THESE FIGURES CAME FROM

Which catalogue, paper or model each of the fields above was read from, where the source named one.

| Field | Value |
| --- | --- |
| Spectral type from | SIMBAD (1995ApJS...99..135A, quality C) |
| Stellar parameters from | Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4) — low confidence: above 7,500 K GSP-Phot's temperature and extinction are degenerate |
| Metallicity from | Median of 2 spectroscopic determinations in 2 papers, compiled from the literature (PASTEL, Soubiran+ 2016); the error bar is the scatter between them |

## Also known as

- Gliese: GJ 9327
- HD: HD 89822
- HIP: HIP 50933
- HR: HR 4072
- Variable star: ET UMa

## Source

[HYG Database v4.1](https://github.com/astronexus/HYG-Database) — CC-BY-SA-4.0

The producer asks: HYG Database v4.1, Astronexus (github.com/astronexus/HYG-Database). Fields derived from it stay under CC BY-SA 4.0.

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

## Cite this page

SpaceCatalog. ET UMa \[catalogue entry\]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/hd-89822

```bibtex
@misc{spacecatalog_hd-89822,
  author       = {{SpaceCatalog}},
  title        = {{ET UMa}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/hd-89822},
  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from HYG Database v4.1.}
}
```

HYG Database v4.1 — CC-BY-SA-4.0

Acknowledgement the producer asks for: HYG Database v4.1, Astronexus (github.com/astronexus/HYG-Database). 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/hd-89822