Observe
1Physical Properties
Magnitude
6.02
Range
4.40 - 11.00
Period
312 days
Variable Type
Mira (Long-period Pulsating)
Spectral Type
M8IIIe
bright giant
Star Color
Red
(B-V 1.30)
Distance
163 ly
3How easy to follow?
Magnitude
4.4 – 11.3 mag
Amplitude
6.9 mag
Period
312.2 d
Type
M
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Imp. | Imp. | Imp. |
| 50 mm finder 50mm finder | V. hard+ | V. hard | Imp. |
| 150 mm telescope 150mm scope | Medium+ | Medium | Hard+ |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
Set a location in User Settings to see visibility data.
Best season
Jan – Mar
(peak: Feb)
5Survey Image
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6Light Curve
7Comparison Stars for R Leo (4.4–11.3)
Nearby stable stars for estimating brightness (AAVSO)
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Explore
8
Size Comparison
Querying VizieR for stellar data…
9
Compare Stars
10
Spectral Classification
11
Hertzsprung-Russell Diagram
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12
Stellar Lifecycle
13
Blackbody Spectrum
14
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
15
Stellar Fusion
Discover
16Stellar Notes
M 4.4 - 11.3v, 309.95d. Period varies from 307.4 to 317.8d. Discovered by Koch in 1782.
R-I corresponds to 7.52V, +1.41(B-V), +0.28(U-B).
Wolf 630 group.
SiO maser. H2O bands. Silicate emission. Also classified M6e-M9.5IIIe.
Speckle interferometer observations show abrupt variations in diameter as a function of wavelength, interpreted as due | to large opacity of TiO. 0.032" at 5400A to 0.054" at 7300A to 0.030" at 7400A. Occultation diam. = 0.067", the | largest measured angular diameter of any star other than the Sun.
17
Light Travel Time Machine
18
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.
Explore Nightbase
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1919 eclipse expedition confirming general relativity; first theory of stellar interiors; the Eddington limit
Biography
Variable Stars — A Guide for Observers
A practical guide to visual observation of variable stars: estimating magnitudes, finding comparison stars, recording data, and contributing to science with AAVSO.
Article
Leo
Mythology, bright stars, and deep-sky highlights.
Constellation
