---
title: "VX UMi"
url: "https://spacecatalog.org/object/hd-155154"
release: "DR1"
licence: "CC-BY-SA-4.0"
citation: "SpaceCatalog. VX UMi [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/hd-155154"
---

# VX UMi

VX UMi is an F2IVnn yellow-white subgiant in the constellation [Ursa Minor](https://spacecatalog.org/constellation/ursa-minor), 152.0 ly from Earth, shining at apparent magnitude 6.17 (V). Other catalogues list it as HD 155154, HIP 83317 and HR 6379.

## At a glance

- **WHAT IT IS:** Yellow-white subgiant
- **HOW FAR:** 152.0 ly — The light arriving now left it that long ago.
- **HOW BRIGHT (V):** 6.17 — Bright enough for the naked eye, under a sky dark enough.
- **WHERE TO LOOK:** [Ursa Minor](https://spacecatalog.org/constellation/ursa-minor) — The patch of sky it sits in, as seen from Earth.

## Properties

| Quantity | Value |
| --- | --- |
| CLASS | F2IVnn yellow-white subgiant |
| MASS | 1.51 M☉ — Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4) |
| DISTANCE FROM EARTH | 152.0 ly — by parallax |
| APPARENT MAGNITUDE (V) | 6.17 |
| ABSOLUTE MAGNITUDE (V) | 2.83 |
| CONSTELLATION | Ursa Minor |
| RIGHT ASCENSION (J2000) | 17h 01m 40.1s |
| DECLINATION (J2000) | +75° 17′ 51.0″ |

## 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 | F2IVnn |
| Surface temperature | 7202 K |
| Luminosity | 6.43873 L☉ |
| Luminosity (bolometric) | 6.1082 L☉ |
| Radius | 1.595 R☉ |
| Mass | 1.509 M☉ |
| Surface gravity (log g) | 4.128 |
| Metallicity (\[Fe/H\]) | −0.2 ±0.22 |
| Age | 9.63×10⁸ years |
| Variability | Gamma Doradus pulsator |
| Variability type (GCVS) | GDOR |
| Variability period | 0.34511 days |

### 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) | 0.306 |
| Variable magnitude, brightest | 6.15 |
| Variable magnitude, faintest | 6.19 |

### 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) | 14.16 mas/yr |
| Proper motion (Dec) | −69.58 mas/yr |
| Radial velocity | 1 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 | VX UMi |

### 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 (2016MNRAS.458.2307K, quality C) |
| Stellar parameters from | Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4) |
| Metallicity from | One spectroscopic determination, compiled from the literature (PASTEL, Soubiran+ 2016) |

## Also known as

- HD: HD 155154
- HIP: HIP 83317
- HR: HR 6379
- Variable star: VX UMi

## 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. VX UMi \[catalogue entry\]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/hd-155154

```bibtex
@misc{spacecatalog_hd-155154,
  author       = {{SpaceCatalog}},
  title        = {{VX UMi}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/hd-155154},
  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-155154