T Monocerotis — Variable Star in Monoceros
Excellent (70/100)
Observe
1Physical Properties
Magnitude
5.98
Range
5.6 - 6.6
Period
27.0 days
Variable Type
Classical Cepheid
Spectral Type
F7Iab-K1Iab
supergiant
Star Color
Red
(B-V 1.22)
Distance
652 ly
2Position & Identifiers
RA
06h 25m 13.1s
Dec
+07° 05' 09.0"
Constellation
Monoceros
(Mon)
HR
2310
HIP
30541
HD
44990
SAO
113845
Variable ID
T Mon
Querying VizieR catalog...
3How easy to follow?
Magnitude
5.6 – 6.6 mag
Amplitude
1.0 mag
Period
27.03 d
Type
DCEP
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | V. hard+ | V. hard | V. hard |
| 50 mm finder 50mm finder | Medium+ | Medium+ | Medium+ |
| 150 mm telescope 150mm scope | Easy | Easy | Easy |
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
Nov – Jan
(peak: Dec)
5Survey Image
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6Light Curve
7Comparison Stars for T Mon (5.6–6.6)
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
CDelta 5.58 - 6.62V, 27.0205d since 1933. Period has increased from 27.0093 before 1900, with mean value 27.024649d.
IUE observations suggest an early-type companion, about A0.
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.
NGC 2236
Open cluster
Open Cluster
mag 8.5
1.1°
Monoceros
Rosette Nebula
NGC 2237
Emission nebula — try an OIII filter
Emission Nebula
mag 6.0
2.7°
Monoceros
Betelgeuse
HIP 27989; Alpha Orionis; 58 Orionis
Semi-regular variable, range 0.4–1.3
Variable Star
mag 0.50
7.5°
Orion
BL Ori
Semi-regular variable, range 5.9–6.6
Variable Star
mag 6.24
7.6°
Orion
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