X Persei — Star in Perseus
Observe
1Physical Properties
Magnitude
6.10
Range
6.02 - 6.83
Period
250 days
Variable Type
Gamma Cassiopeiae (Eruptive Be Star)
Spectral Type
O9.5ep
Star Color
Blue
(B-V 0.29)
(reddened by dust)
2Position & Identifiers
RA
03h 55m 23.0s
Dec
+31° 02' 45.0"
Constellation
Perseus
(Per)
HR
1209
HIP
18350
HD
24534
SAO
56815
Variable ID
X Per
Double Cat
2859
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Hard+ | Hard | V. 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
Oct – Dec
(peak: Nov)
5Survey Image
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6
Size Comparison
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7
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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 2859A, Gamma Cas 6.07 - 7.0V, 580.7?d. Amp. about 0.02U. X-ray period 22.4 hrs. Spectrum variable. Sudden | decrease in H alpha emission followed by 450 sec. flare in continuum. Possible neutron star companion pulsating in | 13.924 min. Simultaneous X-ray and optical obs. 21 Jan. 1975 showed X-ray var. by factor 2 but no corresponding optical | 100 sec. quasi periodic photometric var. may indicate binary with compact companion undergoing mass accretion.
CPM? Component A possibly optical counterpart or companion of X-ray source 4U0352+30. Possibly a triple system with a | neutron star moving around the optical primary in 22.4 hrs., and either apsidal period 581d or close double moving | around a distant component in 581d. Rotational velocity of primary, vsini 306k/s. Component ADS 2859B is normal M1III, | not T Tau type as once assumed.
580.7d, K 59k/s, V0 -50k/s, asini 471. Emission lines var. in RV, 22.4 hrs. and 581d.
Heavily reddened.
May not be member of Per OB2; Zeta Per group.
Sp. data suggest occasional interruption of almost steady infall of material through rotating emission region by | outbursts of material from the star.
Nearby in the Sky
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Visibility scores assume a 150 mm Newton at Bortle 4.
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