2 Lacertae — Star in Lacerta
Observe
1Physical Properties
Magnitude
4.57
Range
4.54 - 4.56
Period
31.4 hours
Variable Type
Slowly Pulsating B Star
Spectral Type
B6V
Star Color
Blue-white
(B-V -0.10)
Distance
82 ly
2Position & Identifiers
RA
22h 21m 01.6s
Dec
+46° 32' 12.0"
Constellation
Lacerta
(Lac)
HR
8523
HIP
110351
HD
212120
SAO
51904
Flamsteed
2 Lac
Double Cat
15862
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium+ | Medium | Hard+ |
| 50 mm finder 50mm finder | Easy | Easy | Easy |
| 150 mm telescope 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
Jul – Sep
(peak: Aug)
5Survey Image
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Explore
6
Size Comparison
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7
Compare Stars
8
Spectral Classification
9
Hertzsprung-Russell Diagram
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10
Stellar Lifecycle
11
Blackbody Spectrum
12
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
13
Stellar Fusion
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14Stellar Notes
ADS 15862A, Ell?, 4.53 - 4.56V.
Visual companion is optical.
ADS 15862A, 2.6164d, K 79.5k/s, V0 -8.9k/s, msin3i 0.873, asini 2.86. Secondary about 1m fainter.
15
Light Travel Time Machine
16
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.
5 Lac
Cool red giant
Star
mag 4.36
1.9°
Lacerta
AR Lac
Eclipsing binary, period 2.0d
Variable Star
mag 6.11
2.3°
Lacerta
NGC 7209
Rich open cluster
Open Cluster
mag 6.7
2.7°
Lacerta
Cocoon Nebula
IC 5146
Emission nebula — try an OIII filter
Emission Nebula
mag 10.0
4.8°
Cygnus
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Article
Lacerta
Mythology, bright stars, and deep-sky highlights.
Constellation
