HIP 21251
HIP 21251
DoubleStar
Tau
Visible
Level 3
Medium telescope (6-8") - Requires steady seeing
Physical Properties
Magnitude
6.25
Spectral Type
B9IVn
Star Color
White
(B-V 0.07)
Distance
1630.8 ly
Position & Identifiers
RA
04h 33m 32.9s
Dec
+18° 00' 60.0"
Constellation
Tau
HR
1442
HIP
21251
Double Cat
3297
Querying VizieR catalog...
Visibility
Set a location in User Settings to see visibility data.
Multiple Star System
Separation
2.9″
Companion Mag
7.0
Position Angle
277°
Star Colors
A: White
B: Yellow-white
Discoverer
STF 559
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
Sep: 2.9″ · PA: 277° · N up, E left
At limit · Rayleigh: 2.3″ · Dawes: 1.9″ · Eff: 3.1″
Size Comparison
Querying VizieR for stellar data…
Stellar Lifecycle
Spectral Classification
Hertzsprung-Russell Diagram
Loading HR diagram…
Blackbody Spectrum
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
Stellar Notes
Binary. No change after 113y.
Survey Image
Loading survey image…