Coordinates

RA: 20^h24^m03^s.818
DEC: +33^∘52'01''.837
Position-uncertainty [arcsec]: 8.025 × 10^-5
Galactic-longitude [deg]: 73.12
Galactic-latitude [deg]: -2.09
Coordinate-Reference

Binary System

Alternative Name: V404 Cyg
X-ray Type: XT, RP, BH, US
Mean Distance [kpc]: 1.24^[1]
Distance Range [kpc]: 1.19 - 1.29^[1]
Hydrogen Column density [10²² cm⁻²]: 0.87
^[1]
G-band Absorption [mag]: 3.24
^[1]

Compact Object

Mass[M_☉]: 10.0^[1]

Orbital Period [d]: 6.4750000000000005^[1]


soft energy band: 0.3-10.0 keV
soft-band flux [10^-12 erg cm^-2 s^-1]:0.3 - 9.58
soft X-ray variability: 31.59

Optical Counterpart

Gaia DR3 Name: 2056188624872569088
Mass[M_☉]: 0.6499999761581421^[1]
Spectral Type: G9/K0III/V^[1]
G [mag]: 17.216(0.009)
^[1]

J [mag]: 13.575(0.025)
^[1]
H [mag]: 12.684(0.027)
^[1]
K [mag]: 12.321(0.026)
^[1]
W1 [mag]: 11.51(0.05)
^[1]
W2 [mag]: 11.45(0.05)
^[1]