DV Aquarii

DV Aquarii

The visual band light curve of DV Aquarii, adapted from Okazaki (1985)[1]
Observation data Epoch J2000      Equinox J2000
Constellation	Aquarius
Right ascension	20h 58m 41.84009s[2]
Declination	−14° 28′ 59.2527″[2]
Apparent magnitude (V)	5.89[3]
Characteristics
Spectral type	A9 V[4]
B−V color index	0.244±0.009[5]
Variable type	β Lyr[6]
Astrometry
Radial velocity (Rv)	+10.3±7.4[7] km/s
Proper motion (μ)	RA: −54.986[2] mas/yr Dec.: −18.428[2] mas/yr
Parallax (π)	11.2032 ± 0.1015 mas[2]
Distance	291 ± 3 ly (89.3 ± 0.8 pc)
Absolute magnitude (MV)	1.25[5]
Orbit[8]
Period (P)	1.5755 d
Eccentricity (e)	0 (adopted)
Inclination (i)	83.18±0.11[9]°
Periastron epoch (T)	2426160.50 JD
Semi-amplitude (K1) (primary)	95.5 km/s
Details
DV Aqr Aa
Mass	1.70[10] M☉
Radius	2.756[9] R☉
Luminosity	28.8+2.6 −2.4[11] L☉
Surface gravity (log g)	3.97[11] cgs
Temperature	7,843±267[12] K
Rotational velocity (v sin i)	103[11] km/s
Age	679[12] Myr
DV Aqr Ab
Mass	1.01[10] M☉
Radius	1.149[9] R☉
Surface gravity (log g)	4.334[9] cgs
Temperature	6,056±240[9] K
Other designations
BD−15° 5848, HD 199603, HIP 103545, HR 8024, SAO 164027[13]
Database references
SIMBAD	data

DV Aquarii is a binary star^[10] system in the zodiac constellation of Aquarius, near the border with Capricornus. It has a peak apparent visual magnitude of 5.89,^[3] which is bright enough to be visible to the naked eye. The distance can be estimated from its annual parallax shift of 11.2 mas,^[2] yielding a separation of 291 light years.

This is a detached eclipsing binary system of the Beta Lyrae type. The orbital period for the system is 1.5755 days and the eccentricity is unknown and probably non-zero;^[8] the orbital inclination is estimated to be 83.18°±0.11°.^[9] During the primary eclipse the magnitude drops to 6.25. It descends to 6.10 with the secondary eclipse (with 6.10 being brighter than 6.25).^[3] The pair have been identified as candidate Herbig Ae/Be stars,^[14] and catalogued as A-type shell stars.^[15]

A magnitude 10.8 star with the designation HD 358087^[16] is a common proper motion companion. It is located at an angular separation of 129″ and has 78% of the Sun's mass. If it is gravitationally bound to the main system, the orbital period is estimated to be around 611,855 years^[10]

This star was a part of the obsolete constellation Norma Nilotica.^{[citation needed]}