About Zosma
Description
Zosma is a white main-sequence star of spectral type A4V at magnitude 2.56 in Leo. Located about 58 light-years from Earth, it has a luminosity of roughly 23 times solar. It marks the hip or rump of the Lion, forming part of the triangle of stars in Leo's hindquarter along with Denebola and Chertan.
Observing Tips
Zosma lies in the Lion's back, forming a triangle with Denebola and Chertan. It is a white star easily found between the Sickle asterism and the tail star Denebola. Best observed February through June when Leo is prominent in the evening sky.
History
The name Zosma comes from the Greek 'zosma,' meaning 'girdle' or 'hip.' An alternate name is Duhr, from Arabic meaning 'the back.' At only 58 light-years, it is one of the nearer A-type main-sequence stars visible to the naked eye.
Fun Facts
Zosma is approaching the end of its main-sequence life and will evolve into a giant star within the next 600 million years. Its spectral type places it in the same class as Sirius, but it is fainter because it is somewhat less massive and slightly farther away.
Observe
1Physical Properties
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
9
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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