---
title: "UCAC4 328-061594 b"
url: "https://spacecatalog.org/object/ucac4-328-061594-b"
release: "DR1"
licence: "No licence stated; acknowledgement requested"
citation: "SpaceCatalog. UCAC4 328-061594 b [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/ucac4-328-061594-b"
---

# UCAC4 328-061594 b

UCAC4 328-061594 b is a gas giant in the constellation [Hydra](https://spacecatalog.org/constellation/hydra), 130.2 ly from Earth. It orbits UCAC4 328-061594 at a mean distance of 19 000 AU. It has a mass of 21.00 M♃ and an estimated radius of 1.08 R♃ · 77 175 km. The radius is an estimate from the mass rather than a measurement. It was discovered in 2024.

## At a glance

- **WHAT IT IS:** Gas giant
- **HOW FAR:** 130.2 ly — The light arriving now left it that long ago.
- **HOW BIG:** 1.08 R♃ · 77 175 km — Its radius: half the width across.
- **WHERE TO LOOK:** [Hydra](https://spacecatalog.org/constellation/hydra) — The patch of sky it sits in, as seen from Earth.

## Properties

| Quantity | Value |
| --- | --- |
| CLASS | Gas giant |
| MASS | 21.00 M♃ |
| RADIUS | 1.08 R♃ · 77 175 km — estimated from the mass, not measured |
| DISTANCE FROM EARTH | 130.2 ly ±0.33 — by NASA Exoplanet Archive sy\_dist (TICv8, 2019AJ....158..138S) |
| ORBITS | UCAC4 328-061594 |
| SEMI-MAJOR AXIS | 19 000 AU |
| CONSTELLATION | Hydra |
| RIGHT ASCENSION (J2000) | 10h 10m 47.8s |
| DECLINATION (J2000) | −24° 27′ 11.8″ |
| DISCOVERED | 2024 |

## 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 |
| --- | --- |
| Host star spectral type | DC |
| Host star mass | 1.19 M☉ |

### 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 |
| --- | --- |
| Host star apparent magnitude (V) | 15.69 |

### THE ORBIT

The shape of the path, where the object sits on it, and the instant those figures were true of. An orbit is a fit to observations and drifts away from the real one either side of its epoch.

| Field | Value |
| --- | --- |
| Host star | UCAC4 328-061594 |
| Stars in system | 1 |
| Planets in system | 1 |

### WHEN IT WAS FOUND

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

| Field | Value |
| --- | --- |
| Discovery method | Imaging |
| Discovered at | Multiple Observatories |

## Also known as

- Exoplanet: UCAC4 328-061594 b
- Host star: UCAC4 328-061594

## Source

[NASA Exoplanet Archive (Planetary Systems Composite Parameters)](https://exoplanetarchive.ipac.caltech.edu/cgi-bin/TblView/nph-tblView?app=ExoTbls&config=PSCompPars) — No licence stated; acknowledgement requested

The producer asks: This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. Cite Christiansen et al. (2025), Planetary Science Journal (doi:10.3847/PSJ/ade3c2), and the literature reference given with each value.

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

## Cite this page

SpaceCatalog. UCAC4 328-061594 b \[catalogue entry\]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/ucac4-328-061594-b

```bibtex
@misc{spacecatalog_ucac4-328-061594-b,
  author       = {{SpaceCatalog}},
  title        = {{UCAC4 328-061594 b}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/ucac4-328-061594-b},
  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from NASA Exoplanet Archive (Planetary Systems Composite Parameters).}
}
```

NASA Exoplanet Archive (Planetary Systems Composite Parameters) — No licence stated; acknowledgement requested

Acknowledgement the producer asks for: This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. Cite Christiansen et al. (2025), Planetary Science Journal (doi:10.3847/PSJ/ade3c2), and the literature reference given with each value.

The page itself, with its pictures, the sky map and the observing tools: https://spacecatalog.org/object/ucac4-328-061594-b