HIP 4845 b

EXOPLANETNeptune-like planet

ILLUSTRATION FROM EQUILIBRIUM TEMPERATURE 358 K · RADIUS 3.89 EARTH RADII · HOST STAR 4010 K

[

OVERVIEW

] EXOPLANET

HIP 4845 b is a Neptune-like planet in the constellation Cetus, 68.81 from Earth. It orbits HIP 4845 at a mean distance of 0.176 . It has a mass of 14.40 and a radius of 3.89 · 24 811 . It was discovered in 2020.

WHAT IT IS
Neptune-like planet
HOW FAR
68.81

The light arriving now left it that long ago.

HOW BIG
3.89 · 24 811

Its radius: half the width across.

WHERE TO LOOK
Cetus

The patch of sky it sits in, as seen from Earth.

ONE ORBIT TAKES
34.1

One trip round HIP 4845.

[

THE MODEL

] CATALOGUED RADIUS
DRAG TO ORBIT

CALCULATED · NOT AN OBSERVATION · CATALOGUED RADIUS · EQUILIBRIUM TEMPERATURE 358 K · RADIUS 3.89 EARTH RADII · HOST STAR 4010 K

Drawn from the catalogued radius and from the same properties the picture at the top of this page uses, at the distance a flight to it would stop. Drag it, or use the arrow keys, to look from another direction. The stars behind are the 498,631 this catalogue holds real distances for, at their real positions and drawn from where the camera actually is — so the constellations are wrong, and that is the point. This is the sky from there, not the sky from here.

[

OBSERVING

] FROM WHERE YOU ARE

What it takes to see HIP 4845 b for yourself. Everything in this part of the page is worked out for a real horizon, a real night and the equipment you say you have.

TONIGHT

Say where you are, and this line says when HIP 4845 b is worth going out for.

[

APPARENT PLACE

] EQUINOX J2026.7

Where a telescope has to be pointed today, which is not quite where the catalogue records the object: the coordinate grid itself has turned since the year 2000 the catalogue is referred to.

RIGHT ASCENSION
DECLINATION
GRID TURNED SINCE
21.7
PROPER MOTION SINCE
none published

Computed for 2026-08-27 00:00 UT. No proper motion is published for HIP 4845 b, so nothing here moves the object; what separates this from the catalogued position above is the coordinate grid turning under it — about fifty arcseconds a year of precession since 2000, and the small nodding of the Earth’s axis on top of that. Aberration and refraction are not included, and neither is parallax; each is under an arcminute, which is also about as well as the catalogued position is known. The same figure for any date.

[

CATALOG DATA

] 15 FIELDS

The raw catalogue values, as the source published them, with the error bars where one was published — sorted by what each set of figures is about rather than by the order they happened to be stored in.

WHAT IT IS MADE OF

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

Equilibrium temperature
358.21
Host star spectral type
Host star temperature
4010 +123 / −134
Host star mass
0.62 ±0.04
Host star radius
0.603999 +0.028 / −0.07

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.

Host star apparent magnitude ()

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.

Host star
HIP 4845
Orbital period
34.15 ±0.046
Eccentricity
±0.14
Argument of periastron
108 ±72
Periastron epoch
2454702.0000
Stars in system
1
Planets in system
1

WHEN IT WAS FOUND

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

Discovery method
Radial Velocity
Discovered at
Multiple Observatories
[

ALSO KNOWN AS

] 2 DESIGNATIONS
  • Exoplanet HIP 4845 b
  • Host star HIP 4845
[

LOOK IT UP ELSEWHERE

] 4 SERVICES

Each link carries the identifier printed beside it. Nothing on this page is a measurement of our own, so a number that disagrees with one of these is worth reporting — and a service that has never catalogued this object under this name will say so plainly.

[

CITE THIS PAGE

] DR1

This page is live and its numbers move when an upstream refreshes, so the citation names the release the rows belong to rather than the day you read them. The release itself is frozen, republished as a bundle, and is what a data-availability statement should point at.

PLAIN TEXT
SpaceCatalog. HIP 4845 b [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/hip-4845-b
BIBTEX
@misc{spacecatalog_hip-4845-b,
  author       = {{SpaceCatalog}},
  title        = {{HIP 4845 b}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/hip-4845-b},
  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from NASA Exoplanet Archive (Planetary Systems Composite Parameters).}
}

The values above were taken from NASA Exoplanet Archive (Planetary Systems Composite Parameters) — Public domain (NASA). Citing this page does not replace citing that catalogue.

[

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