Aquila X-1

Aquila X-1 (frequently abbreviated to Aql X-1) is a low-mass x-ray binary (LMXB) and the most luminous X-Ray source in the constellation Aquila. It was first observed by the satellite Vela 5B which detected several outbursts from this source between 1969 and 1976.^[4] Its optical counterpart is variable, so it was named V1333 Aql according to the IAU standards. The system hosts a neutron star that accretes matter from a main sequence star of spectral type K4.^[3] The binary's orbital period is 18.9479 hours.^[1]

Aquila X-1

A visual band light curve for Aquila X-1 during a July 1996 outburst, adapted from Garcia et al. (1999)[1]
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Aquila
Right ascension	19h 11m 16.05720s[2]
Declination	+00° 35′ 05.8767″[2]
Characteristics
Spectral type	K4[3]
Variable type	LMXB[4]
Other designations
V1333 Aql, 2MASS J19111604+0035058[5]
Database references
SIMBAD	data

The neutron star radiation flux is slightly variable due to the nuclear burning of the accreted helium on the surface.^[6]