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HR 4729 — Star in Crux

Magnitude 4.9m Star Crux (Cru) Visible
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1Physical Properties

Magnitude 4.86
Spectral Type B4IV subgiant
Star Color Blue-white (B-V -0.12)

2Position & Identifiers

RA 12h 26m 30.9s
Dec -63° 07' 21.0"
Constellation Crux (Cru)
HR 4729
HD 108250
SAO 251903

3How easy to spot?

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Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Medium+ Medium Hard+
50mm finder Easy Easy Easy
150mm scope Easy Easy Easy
Easy Medium Hard Very hard Impossible

Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs

4Visibility

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Best season Feb – Apr (peak: Mar)

5Survey Image

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6

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7

Spectral Classification

8

Hertzsprung-Russell Diagram

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Read: The Hertzsprung-Russell Diagram — Reading Stars Like a Map
9

Stellar Lifecycle

10

Blackbody Spectrum

11

Stellar Absorption Spectrum

Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.

12

Stellar Fusion

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13Stellar Notes

Component C of triple system with HR 4730-4731, at 90" CPM.
1.225155d, K 43.1k/s, V0 +8.4k/s, asini 0.726.
Sco-Cen assoc.

Nearby in the Sky

Other targets within a few degrees — pan your scope a little and keep exploring.

Visibility scores assume a 150 mm Newton at Bortle 4.

Acrux
HIP 60718; Alpha1 Crucis
Easy
Easy double, sep 3.5″
Double Star mag 1.33 0.0° Crux
Alpha Cru
HIP 60718; Alpha2 Crucis
Easy
Hot blue O-type star
Star mag 1.73 0.0° Crux
NGC 4349
Easy
Open cluster
Open Cluster mag 7.4 1.3° Crux
Coalsack Nebula
Easy
Dark nebula — shows as a void against the Milky Way
Dark Nebula mag 12.0 2.4° Crux
Epsilon Mus
Hard+
Semi-regular variable, range 4.0–4.3
Variable Star mag 4.11 4.9° Musca
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