Registry · exoplanet

alf Tau b

Exoplanet

harvesting The full record is being pulled from the archives right now — measurement tables, the Gaia row, catalogue photometry. This page will fill itself in.

Right ascension: 04h 35m 55.24s
Declination: +16° 30′ 33.1″
Galactic l, b: 180.97, -20.25
Magnitude V: 0.872
Distance: 20.433 pc

Planet

NASA Exoplanet Archive, composite parameters

Host star	alf Tau · K5 III
Discovery	Radial Velocity, 2015 · Multiple Observatories
Orbital period	628.96 d
Semi-major axis	1.46 au
Eccentricity	0.1
Radius	12.7 R⊕ · 1.13 R♃
Mass	2,056.4 M⊕ · 6.47 M♃
Density	5.52 g/cm³
Equilibrium temperature	1,086.8 K
System distance	20.433 pc

Recorded parameters

4 quantities with a single published value

Parameter	Value	Unit	Uncertainty	As published	Source	Reference
Mass	2,056.36	M_earth	± 168.4	Radial Velocity	NASA Exoplanet Archive	Hatzes et al. 2015
Orbital period	628.96	d	± 0.9	Radial Velocity	NASA Exoplanet Archive	Hatzes et al. 2015
Semi-major axis	1.46	au	± 0.27	Radial Velocity	NASA Exoplanet Archive	Hatzes et al. 2015
Eccentricity	0.1		± 0.05	Radial Velocity	NASA Exoplanet Archive	Hatzes et al. 2015

In the same field

within 9 arcmin · wider search

Object	Type	Separation	V
alf Tau	Star	0″	—
* alf Tau	LongPeriodV* Candidate	0.3669″	0.86
* alf Tau b	Planet	0.3669″	—
* alf Tau B	HighPM*	31.15″	13.6
BD+16 630	**	133.3″	10.71
HD 285910	Star	340.7″	10.59
G 83-21	HighPM*	480.2″	—

Provenance

where this card came from

Archive	Read at (UTC)	Record
Seeded from the bulk archive load; no per-object fetch yet.

Machine-readable: /api/v1/object/alf-tau-b · Registry entry updated 2026-08-14.