Theta Carinae — Star in Carina
About Theta Car
Description
Theta Carinae is a blue main-sequence star of spectral type B0Vp at magnitude 2.76, located roughly 460 light-years from Earth. It is the brightest member of the open cluster IC 2602, popularly known as the Southern Pleiades or Theta Carinae Cluster. With a surface temperature of about 31,000 K, it is an extremely hot star with a luminosity around 25,000 times solar.
Observing Tips
Theta Car is the dominant star of the Southern Pleiades cluster (IC 2602), which is visible to the naked eye as a hazy patch in the southern Milky Way. Binoculars or a small telescope reveal a beautiful scattering of bright stars around Theta Car, reminiscent of the Pleiades. The cluster spans about 50 arcminutes. Best observed from February through May from southern latitudes.
History
The Southern Pleiades cluster (IC 2602) was noted by Lacaille during his observations from the Cape of Good Hope in the 1750s. Theta Carinae dominates the cluster and gives it its alternate name. The cluster is relatively young — about 30 million years old — with hot blue stars that have not yet evolved significantly.
Fun Facts
The Southern Pleiades is sometimes considered the southern-hemisphere counterpart of the famous Pleiades (M45). While less well-known, it is actually spread over a similar area of sky and contains several stars bright enough to see with the naked eye. Theta Car's 'p' spectral suffix indicates chemical peculiarities in its atmosphere.
Observe
1Physical Properties
2Position & Identifiers
3How easy to spot?
| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Easy | Easy | Easy |
| 50 mm finder 50mm finder | Easy | Easy | Easy |
| 150 mm telescope 150mm scope | Easy | Easy | Easy |
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
Set a location in User Settings to see visibility data.
5Survey Image
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Explore
7
Size Comparison
8
Compare Stars
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Spectral Classification
10
Hertzsprung-Russell Diagram
11
Stellar Lifecycle
12
Blackbody Spectrum
13
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
14
Stellar Fusion
Discover
15Stellar Notes
16
Light Travel Time Machine
17
Relativistic Travel
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.
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