---
title: "V740 Cas"
url: "https://spacecatalog.org/object/hd-404"
release: "DR1"
licence: "CC-BY-SA-4.0"
citation: "SpaceCatalog. V740 Cas [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/hd-404"
---

# V740 Cas

V740 Cas is a G5 yellow [star](https://spacecatalog.org/stars) in the constellation [Cassiopeia](https://spacecatalog.org/constellation/cassiopeia), 98.78 ly from Earth, shining at apparent magnitude 8.57 (V). Other catalogues list it as HD 404 and HIP 723.

## At a glance

- **WHAT IT IS:** Yellow star
- **HOW FAR:** 98.78 ly — The light arriving now left it that long ago.
- **HOW BRIGHT (V):** 8.57 — Binoculars reach it; the naked eye does not.
- **WHERE TO LOOK:** [Cassiopeia](https://spacecatalog.org/constellation/cassiopeia) — The patch of sky it sits in, as seen from Earth.

## Properties

| Quantity | Value |
| --- | --- |
| CLASS | G5 yellow star |
| DISTANCE FROM EARTH | 98.78 ly — by parallax |
| APPARENT MAGNITUDE (V) | 8.57 |
| ABSOLUTE MAGNITUDE (V) | 6.16 |
| CONSTELLATION | Cassiopeia |
| RIGHT ASCENSION (J2000) | 00h 08m 57.1s |
| DECLINATION (J2000) | +66° 27′ 24.0″ |

## 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 | G5 |
| Surface temperature | 5040 K |
| Luminosity | 0.298126 L☉ |
| Luminosity (bolometric) | 0.4626 L☉ |
| Radius | 0.892 R☉ |
| Surface gravity (log g) | 4.485 |
| Variability | Semiregular pulsating giant or supergiant (F, G or K) |
| Variability type (GCVS) | SRD: |
| Variability period | 356 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) | 0.885 |
| Variable magnitude, brightest | 8.52 |
| Variable magnitude, faintest | 8.63 |

### 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) | 174.82 mas/yr |
| Proper motion (Dec) | 5.96 mas/yr |
| Radial velocity | −59.7 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 | V740 Cas |
| Washington Double Star id | 00089+6627 |

### 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 (1993yCat.3135....0C, quality E) |
| Stellar parameters from | Gaia DR3 model fit (GSP-Phot, FLAME; RUWE ≤ 1.4) |

## Also known as

- HD: HD 404
- HIP: HIP 723
- Variable star: V740 Cas

## 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. V740 Cas \[catalogue entry\]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/hd-404

```bibtex
@misc{spacecatalog_hd-404,
  author       = {{SpaceCatalog}},
  title        = {{V740 Cas}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/hd-404},
  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-404