RGB composite color image of the shell surrounding the nova DQ Her, made from three narrow band images: Blue = 4800 Å, green = Hα at 6563 Å and red = [NII] at 6583 Å. From Santamaria et al. 2020 [1] | |
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Hercules |
Right ascension | 18h 07m 30.25108s [2] |
Declination | +45° 51′ 32.5646″ [2] |
Apparent magnitude (V) | 1.5 [3] - 15.16 [4] |
Characteristics | |
Spectral type | DBe + M2V |
Variable type | DQ Her [5] |
Astrometry | |
Proper motion (μ) |
RA: −0.948
[2]
mas/
yr Dec.: +12.423 [2] mas/ yr |
Parallax (π) | 1.9975 ± 0.0237 mas [2] |
Distance | 1,630 ± 20
ly (501 ± 6 pc) |
Absolute magnitude (MV) | −6.94 [6] |
Orbit | |
Period (P) | 0.1936208977 ± 0.0000000017 d [7] |
Semi-major axis (a) | 0.003 AU |
Inclination (i) | 86.5±1.6 [8]° |
Details | |
A | |
Mass | 0.6 [9] M☉ |
Radius | 0.0121 [8] R☉ |
B | |
Mass | 0.4 [9] M☉ |
Other designations | |
Database references | |
SIMBAD | data |
DQ Herculis, or Nova Herculis 1934, was a slow, bright nova occurring in the northern constellation of Hercules in December 1934. This cataclysmic variable star was discovered on 13 December 1934 by J. P. M. Prentice from Stowmarket, Suffolk. [12] It reached peak brightness on 22 December 1934 with an apparent magnitude of 1.5. [3] The nova remained visible to the naked eye for several months. [13]
This is a binary star system consisting of a white dwarf primary with an estimated 60% of the mass of the Sun and a red dwarf secondary with 40% of the Sun's mass. [8] They orbit each other tightly with a period of 4.65 hours. [7] The system shows orbital period variation, possibly due to the presence of a third body. [5] The orbital plane of the pair is inclined by an angle of 86.5° to the line of sight from the Earth, causing the white dwarf to undergo a deep eclipse every orbit. [8]
DQ Herculis is the prototype for a category of cataclysmic variable stars called intermediate polars. [5] The red dwarf has filled its Roche lobe and matter is being drawn off at the rate of 2.7 × 10−9 M☉ yr−1, forming an accretion disk orbiting the primary. This disk has inferred temperatures ranging from 5,000 to 13,500 K. A bright spot in the inner disk appears to pulsate with a 71-second period. In this class of variables, the white dwarf is magnetized, directing infalling matter onto the magnetic poles. [8]
The shell of ejected material from the nova outburst is visible as an emission nebula, similar in appearance to a planetary nebula. This roughly elliptical nebula had a size of 32.0 × 24.2 arc seconds as of 2018, and it is expanding at a rate of about 0.16 arc seconds per year. [1]
The nova was one of the brightest objects observable in the night sky. In addition to scientific articles, and received significant coverage in popular news publications. [14] [15] Brad Ricca, an English professor at Case Western Reserve University, has suggested that Nova Herculis may have influenced the development of the origin story of the comic book superhero Superman. [16]
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cite web}}
: CS1 maint: postscript (
link)
RGB composite color image of the shell surrounding the nova DQ Her, made from three narrow band images: Blue = 4800 Å, green = Hα at 6563 Å and red = [NII] at 6583 Å. From Santamaria et al. 2020 [1] | |
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Hercules |
Right ascension | 18h 07m 30.25108s [2] |
Declination | +45° 51′ 32.5646″ [2] |
Apparent magnitude (V) | 1.5 [3] - 15.16 [4] |
Characteristics | |
Spectral type | DBe + M2V |
Variable type | DQ Her [5] |
Astrometry | |
Proper motion (μ) |
RA: −0.948
[2]
mas/
yr Dec.: +12.423 [2] mas/ yr |
Parallax (π) | 1.9975 ± 0.0237 mas [2] |
Distance | 1,630 ± 20
ly (501 ± 6 pc) |
Absolute magnitude (MV) | −6.94 [6] |
Orbit | |
Period (P) | 0.1936208977 ± 0.0000000017 d [7] |
Semi-major axis (a) | 0.003 AU |
Inclination (i) | 86.5±1.6 [8]° |
Details | |
A | |
Mass | 0.6 [9] M☉ |
Radius | 0.0121 [8] R☉ |
B | |
Mass | 0.4 [9] M☉ |
Other designations | |
Database references | |
SIMBAD | data |
DQ Herculis, or Nova Herculis 1934, was a slow, bright nova occurring in the northern constellation of Hercules in December 1934. This cataclysmic variable star was discovered on 13 December 1934 by J. P. M. Prentice from Stowmarket, Suffolk. [12] It reached peak brightness on 22 December 1934 with an apparent magnitude of 1.5. [3] The nova remained visible to the naked eye for several months. [13]
This is a binary star system consisting of a white dwarf primary with an estimated 60% of the mass of the Sun and a red dwarf secondary with 40% of the Sun's mass. [8] They orbit each other tightly with a period of 4.65 hours. [7] The system shows orbital period variation, possibly due to the presence of a third body. [5] The orbital plane of the pair is inclined by an angle of 86.5° to the line of sight from the Earth, causing the white dwarf to undergo a deep eclipse every orbit. [8]
DQ Herculis is the prototype for a category of cataclysmic variable stars called intermediate polars. [5] The red dwarf has filled its Roche lobe and matter is being drawn off at the rate of 2.7 × 10−9 M☉ yr−1, forming an accretion disk orbiting the primary. This disk has inferred temperatures ranging from 5,000 to 13,500 K. A bright spot in the inner disk appears to pulsate with a 71-second period. In this class of variables, the white dwarf is magnetized, directing infalling matter onto the magnetic poles. [8]
The shell of ejected material from the nova outburst is visible as an emission nebula, similar in appearance to a planetary nebula. This roughly elliptical nebula had a size of 32.0 × 24.2 arc seconds as of 2018, and it is expanding at a rate of about 0.16 arc seconds per year. [1]
The nova was one of the brightest objects observable in the night sky. In addition to scientific articles, and received significant coverage in popular news publications. [14] [15] Brad Ricca, an English professor at Case Western Reserve University, has suggested that Nova Herculis may have influenced the development of the origin story of the comic book superhero Superman. [16]
{{
cite web}}
: CS1 maint: postscript (
link)