DK Lacertae

Last updated
DK Lacertae
DKLacLocation.png
Location of DK Lacertae (circled in red)
Observation data
Epoch J2000       Equinox J2000
Constellation Lacerta
Right ascension 22h 49m 46.93149s [1]
Declination +53° 17 19.7993 [1]
Apparent magnitude  (V)5.0 – 15.5 [2] (var.)
Characteristics
Variable type classical nova [2]
Astrometry
Proper motion (μ)RA: −1.945 [1]   mas/yr
Dec.: −1.722 [1]   mas/yr
Parallax (π)0.4026 ± 0.0697  mas [1]
Distance 2517+788
−261
[3]   pc
Details
DK Lac B
Mass 1.03 [4]   M
Other designations
Nova Lacertae 1950, DK Lac, AAVSO 2245+52, 2MASS J22494690+5317192. Gaia DR2 2002440098459791744 [5]
Database references
SIMBAD data
The light curve of DK Lacertae, plotted from AAVSO data. Note the post outburst "jitters" (local maxima) during 1950. DKLacLightCurve.png
The light curve of DK Lacertae, plotted from AAVSO data. Note the post outburst "jitters" (local maxima) during 1950.

DK Lacertae (Nova Lacertae 1950) was a nova, which lit up in the constellation Lacerta in 1950. The nova was discovered by Charles Bertaud of the Paris Observatory on a photographic plate taken on 23 January 1950. At the time of its discovery, it had an apparent magnitude of 6.1. [6] DK Lacertae reached peak magnitude 5.0, making it easily visible to the naked eye. [2]

DK Lacertae's post-eruption light curve was remarkable for the large number of outbursts of a magnitude or more which occurred in the months after the main nova event. [7] [8] Strope et al. (2010) reported that there were 14 of these "jitters" in the light curve, and they used this star as the prototype object for their type J light curve class. [9] It took about 60 days for the nova to drop from peak brightness by 3 magnitudes, which makes DK Lacertae a "fast" nova. [10]

X-ray emission has been detected from this system. [11]

All novae are binary stars, with a "donor" star orbiting a white dwarf. The donor star is so close to the white dwarf that matter is transferred from the donor to an accretion disk surrounding the white dwarf. In the case of DK Lacertae, Shara et al. (2018) estimate that the white dwarf has a mass of 1.03M and the donor star is transferring 3.4 × 10−8M yr−1 to the accretion disk. [4] The orbital periods of nova are typically a few hours, but no photometric periodicity on that timescale has been found for DK Lac, suggesting that we are viewing the accretion disk nearly face-on. [12]

A faint shell was detected around the source in 1995, with a radius of about 2.0–2.5 , [13] but later observations with the Hubble Space Telescope failed to detect the shell. [14]

Related Research Articles

<span class="mw-page-title-main">V1974 Cygni</span> Star in the constellation Cygnus

V1974 Cygni or Nova Cygni 1992 was a nova, visible to the naked eye, in the constellation Cygnus. It was discovered visually with 10×50 binoculars on February 19, 1992, by Peter Collins, an amateur astronomer living in Boulder, Colorado. At that time he first noticed it, it had an apparent magnitude of 7.2. Nine hours later he saw it again, and it had brightened by a full magnitude. For this discovery Collins was awarded the AAVSO Nova Award in 1993. The nova reached magnitude 4.4 at 22:00 UT on 22 February 1992. Images from the Palomar Sky Survey taken before the nova event showed identified a possible precursor which had photographic magnitudes of 18 and 17, but the identification of the precursor is not firm.

<span class="mw-page-title-main">V382 Velorum</span> 1999 Nova seen in the constellation Vela

V382 Velorum, also known as Nova Velorum 1999, was a bright nova which occurred in 1999 in the southern constellation Vela. V382 Velorum reached a brightness of 2.6 magnitude, making it easily visible to the naked eye. It was discovered by Peter Williams of Heathcote, New South Wales, Australia at 09:30 UT on 22 May 1999. Later that same day it was discovered independently at 10:49 UT by Alan C. Gilmore at Mount John University Observatory in New Zealand.

<span class="mw-page-title-main">T Aurigae</span> Nova seen in 1891

T Aurigae was a nova, which lit up in the constellation Auriga in 1891. Thomas David Anderson, an amateur astronomer in Edinburgh, reported that he was "almost certain" he saw the nova at 02:00 UT on 24 January 1892, when it was slightly brighter than χ Aurigae. He mistook the star for 26 Aurigae, although he noted to himself that it seemed brighter than he remembered it being. He saw it twice more during the following week. On 31 January 1892 he realized his mistake, and wrote a note to Ralph Copeland reporting his discovery. Professor Copeland immediately reported the discovery via telegram to William Huggins, who made the first spectroscopic observations of T Aurigae on 2 February 1892, when the star was a magnitude 4.5 object. T Aurigae was the first nova to be observed spectroscopically.

<span class="mw-page-title-main">DI Lacertae</span> 1910 Nova in the constellation Lacerta

DI Lacertae or Nova Lacertae 1910 was a nova in constellation Lacerta which appeared in 1910. It was discovered by Thomas Henry Espinell Compton Espin at Wolsingham Observatory on 30 Dec 1910, at which time it was an 8th magnitude object. Subsequent examination of pre-discovery photographic plates showed that the outburst occurred sometime between 17 November 1910 and 23 November 1910. It reached a peak brightness of magnitude 4.6 on 26 November 1910, making it visible to the naked eye. Before the nova event DI Lacertae was a 14th magnitude star, and by 1950 it had returned to 14th magnitude.

<span class="mw-page-title-main">CP Lacertae</span> 1936 Nova seen in the constellation Lacerta

CP Lacertae was a nova, which lit up on June 18, 1936 in the constellation Lacerta. It was discovered independently by several observers including Leslie Peltier in the US, E. Loreta in Italy, and Kazuaki Gomi, a Japanese barber who discovered the nova during the 19 June 1936 total solar eclipse.

<span class="mw-page-title-main">BT Monocerotis</span> Nova seen in 1939

BT Monocerotis was a nova, which lit up in the constellation Monoceros in 1939. It was discovered on a spectral plate by Fred L. Whipple on December 23, 1939. BT Monocerotis is believed to have reached mag 4.5, which would have made it visible to the naked eye, but that value is an extrapolation; the nova was not observed at peak brightness Its brightness decreased after the outbreak by 3 magnitudes in 182 days, making it a "slow nova". The light curve for the eruption had a long plateau period.

<span class="mw-page-title-main">V476 Cygni</span> Star in the constellation Cygnus

V476 Cygni or Nova Cygni 1920 was a nova which occurred in the constellation Cygnus in 1920. It was discovered by William Frederick Denning, an English amateur astronomer, at 09:30 GMT on 20 August 1920, at which time it had a magnitude of 3.7. It reached a peak brightness of magnitude 1.7 on 23 August 1920. Its quiescent brightness is magnitude 17.09.

<span class="mw-page-title-main">HR Lyrae</span> Nova that appeared in 1919

HR Lyrae or Nova Lyrae 1919 was a nova which occurred in the constellation Lyra in 1919. Its discovery was announced by Johanna C. Mackie on 6 December 1919. She discovered it while examining photographic plates taken at the Harvard College Observatory. The bulletin announcing the discovery states "Between December 4 and 6 it rose rapidly from the sixteenth magnitude or fainter, to a maximum of about 6.5". It was the first nova ever reported in Lyra, and Mackie was awarded the AAVSO gold medal for her discovery. Its peak magnitude of 6.5 implies that it might have been visible to the naked eye, under ideal conditions.

<span class="mw-page-title-main">V849 Ophiuchi</span> Nova in the constellation Ophiuchus

V849 Ophiuchi or Nova Ophiuchi 1919 was a nova that erupted in 1919, in the constellation Ophiuchus, and reached a blue band brightness of magnitude 7.2. Joanna C. S. Mackie discovered the star while she was examining Harvard College Observatory photographic plates. The earliest plate it was visible on was exposed on August 20, 1919, when the star was at magnitude 9.4. It reached magnitude 7.5 on September 13 of that year. In its quiescent state it has a visual magnitude of about 18.8. V849 Ophiuchi is classified as a "slow nova"; it took six months for it to fade by three magnitudes.

<span class="mw-page-title-main">NQ Vulpeculae</span> 1976 Nova seen in the constellation Vulpecula

NQ Vulpeculae also known as Nova Vulpeculae 1976, was a nova that appeared in the constellation Vulpecula in 1976. It was discovered visually at 18:20 UT on October 21, 1976 by English amateur astronomer George Alcock. Its apparent magnitude at the time of discovery was 6.5 It reached its maximum brightness of magnitude 6.0 thirteen days after its discovery, at which point it may have been faintly visible to the naked eye. A few days after maximum brightness, it had faded to magnitude 8.3.

<span class="mw-page-title-main">V838 Herculis</span> 1991 Nova seen in the constellation Hercules

V838 Herculis, also known as Nova Herculis 1991, was a nova which occurred in the constellation Hercules in 1991. It was discovered by George Alcock of Yaxley, Cambridgeshire, England at 4:35 UT on the morning of 25 March 1991. He found it with 10×50 binoculars, and on that morning its apparent visual magnitude was 5. Palomar Sky Survey plates showed that before the outburst, the star was at photographic magnitude 20.6 and 18.25.

<span class="mw-page-title-main">V1494 Aquilae</span> Nova seen in 1999 in the constellation of Aquila

V1494 Aquilae or Nova Aquilae 1999 b was a nova which occurred during 1999 in the constellation Aquila and reached a brightness of magnitude 3.9 on 2 December 1999. making it easily visible to the naked eye. The nova was discovered with 14×100 binoculars by Alfredo Pereira of Cabo da Roca, Portugal at 18:50 UT on 1 December 1999, when it had a visual magnitude of 6.0.

<span class="mw-page-title-main">HR Delphini</span> 1967 Nova seen in the constellation Delphinus

HR Delphini, also known as Nova Delphini 1967, was a nova which appeared in the constellation Delphinus in 1967. It was discovered by George Alcock at 22:35 UT on 8 July 1967, after searching the sky for over 800 hours with binoculars. At the time of discovery it had an apparent magnitude of 5.0. It reached a peak brightness of magnitude 3.5 on 13 December 1967, making it easily visible to the naked eye around that time. Pre-outburst photographs taken with the Samuel Oschin telescope showed it as a ~12th magnitude star which might have been variable.

<span class="mw-page-title-main">SU Ursae Majoris</span> Variable star in the constellation Ursa Major

SU Ursae Majoris, or SU UMa, is a close binary star in the northern circumpolar constellation of Ursa Major. It is a periodic cataclysmic variable that varies in magnitude from a peak of 10.8 down to a base of 14.96. The distance to this system, as determined from its annual parallax shift of 4.53 mas, is 719 light-years. It is moving further from the Earth with a heliocentric radial velocity of +27 km/s.

<span class="mw-page-title-main">V455 Andromedae</span> Dwarf nova star in the constellation Andromeda

V455 Andromedae is a dwarf nova in the constellation Andromeda. It has a typical apparent visual magnitude of 16.5, but reached a magnitude of 8.5 during the only observed outburst.

<span class="mw-page-title-main">QZ Aurigae</span> Nova seen in 1964

QZ Aurigae, also known as Nova Aurigae 1964, was a nova which occurred in the constellation Auriga during 1964. It was discovered by Nicholas Sanduleak on an objective prism photographic plate taken at the Warner and Swasey Observatory on 4 November 1964. Examination of pre-discovery plates from Sonneberg Observatory showed that the eruption occurred in early February 1964, and it had a photographic magnitude of 6.0 on 14 February 1964. Its brightness declined in images taken after the 14th, suggesting that its peak brightness was above 6.0. It was probably visible to the naked eye for a short time.

<span class="mw-page-title-main">LV Vulpeculae</span> Nova seen in 1968 in the constellation Vulpecula

LV Vulpeculae, also known as Nova Vulpeculae 1968 no. 1, was the first of two novae in the constellation of Vulpecula which erupted in 1968. It was discovered by George Alcock who observed it from the back garden of his home in Farcet, England, on the morning of 15 April 1968. The next night it was independently discovered by Midtskoven in Norway. It reached a peak apparent magnitude of 4.79 on 17 April 1968. It was visible to the naked eye at the same time HR Delphini was a naked eye object, and the two novae were less than 15 degrees apart on the sky.

<span class="mw-page-title-main">GI Monocerotis</span> 1918 Nova in the constellation Monoceros

GI Monocerotis, also known as Nova Monocerotis 1918, was a nova that erupted in the constellation Monoceros during 1918. It was discovered by Max Wolf on a photographic plate taken at the Heidelberg Observatory on 4 February 1918. At the time of its discovery, it had a photographic magnitude of 8.5, and had already passed its peak brightness. A search of plates taken at the Harvard College Observatory showed that it had a photographic magnitude of 5.4 on 1 January 1918, so it would have been visible to the naked eye around that time. By March 1918 it had dropped to ninth or tenth magnitude. By November 1920 it was a little fainter than 15th magnitude.

<span class="mw-page-title-main">V1370 Aquilae</span> Nova that occurred in 1982

V1370 Aquilae, also known as Nova Aquilae 1982, is a nova that appeared in the constellation Aquila during 1982. It was discovered by Minoru Honda of Kurashiki, Japan at 20:30 UT on 27 January 1982. At that time the Sun had moved just far enough from Aquila to allow the nova to be seen in the morning sky. Although it was discovered photographically, its apparent magnitude was 6–7, making it potentially visible to the naked eye under ideal conditions. A possible magnitude 20 progenitor was located on the Palomar Sky Survey prints. Spectra of the object were taken in February 1982 at Asiago Astrophysical Observatory, which confirmed that it is a nova.

<span class="mw-page-title-main">OY Arae</span> 1910 nova in the constellation Ara

OY Arae, also known as Nova Arae 1910, is a nova in the constellation Ara. It was discovered by Williamina Fleming on a Harvard Observatory photographic plate taken on April 4, 1910. At that time it had a magnitude of 6.0, making it faintly visible to the naked eye under ideal observing conditions. Examination of earlier plates showed that before the outburst it was a magnitude 17.5 object, and by March 19, 1910, it had reached magnitude 12.

References

  1. 1 2 3 4 5 Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics . 616. A1. arXiv: 1804.09365 . Bibcode: 2018A&A...616A...1G . doi: 10.1051/0004-6361/201833051 .
  2. 1 2 3 Samus', N. N; Kazarovets, E. V; Durlevich, O. V; Kireeva, N. N; Pastukhova, E. N (2017). "General catalogue of variable stars: Version GCVS 5.1". Astronomy Reports. 61 (1): 80. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID   125853869.
  3. Schaefer, Bradley E. (December 2018). "The distances to Novae as seen by Gaia". Monthly Notices of the Royal Astronomical Society. 481 (3): 3033–3051. arXiv: 1809.00180 . Bibcode:2018MNRAS.481.3033S. doi: 10.1093/mnras/sty2388 .
  4. 1 2 Shara, Michael M.; et al. (June 2018). "The Masses and Accretion Rates of White Dwarfs in Classical and Recurrent Novae". The Astrophysical Journal. 860 (2): 11. arXiv: 1804.06880 . Bibcode:2018ApJ...860..110S. doi: 10.3847/1538-4357/aabfbd . S2CID   55851634. 110.
  5. "DK Lac". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 3 September 2018.
  6. Duerbeck, Hilmar W. (March 1987). "A Reference Catalogue and Atlas of Galactic Novae". Space Science Reviews. 45 (1–2): 1–14. Bibcode:1987SSRv...45....1D. doi:10.1007/BF00187826. S2CID   115854775.
  7. Bochníček, Z. (February 1951). "Light Curve of Nova DK Lacertae 1950". Bulletin of the Astronomical Institutes of Czechoslovakia. 2: 88. Bibcode: 1951BAICz...2...88B .
  8. Ribbe, John (February 1951). "The Light-Curve of Nova Lacertae 1950". Publications of the Astronomical Society of the Pacific. 63 (370): 39. Bibcode:1951PASP...63...39R. doi: 10.1086/126314 .
  9. Strope, Richard J.; Schaefer, Bradley E.; Henden, Arne A. (July 2010). "Catalog of 93 Nova Light Curves: Classification and Properties". The Astronomical Journal. 140 (1): 34–62. arXiv: 1004.3698 . Bibcode:2010AJ....140...34S. doi: 10.1088/0004-6256/140/1/34 .
  10. Selvelli, Pierluigi; Gilmozzi, Roberto (February 2019). "A UV and optical study of 18 old novae with Gaia DR2 distances: mass accretion rates, physical parameters, and MMRD". Astronomy & Astrophysics. 622: A186. arXiv: 1903.05868 . Bibcode:2019A&A...622A.186S. doi: 10.1051/0004-6361/201834238 .
  11. Boardman, S. F.; et al. (January 2016). "X-ray detection of the old nova DK Lacertae". The Astronomer's Telegram. 8610: 1. Bibcode:2016ATel.8610....1B.
  12. Honeycutt, R.K.; Kafka, S.; Jacobson, H.; Henden, A.A.; Hoffman, D.; Maxwell, T.; Robertson, J.W.; Croxall, K. (April 2011). "The 2001-2003 Low State of Nova Lacertae 1950 (DK Lac)". The Astronomical Journal. 141 (4): 122. arXiv: 1102.3759 . Bibcode:2011AJ....141..122H. doi: 10.1088/0004-6256/141/4/122 .
  13. Slavin, A.J.; O'Brien, T.J.; Dunlop, J.S. (September 1995). "A deep optical imaging study of the nebular remnants of classical novae". Monthly Notices of the Royal Astronomical Society. 276 (2): 353–371. Bibcode:1995MNRAS.276..353S. doi: 10.1093/mnras/276.2.353 .
  14. Gill, C. D.; O'Brien, T. J. (May 2000). "Hubble Space Telescope imaging and ground-based spectroscopy of old nova shells - I. FH Ser, V533 Her, BT Mon, DK Lac and V476 Cyg". Monthly Notices of the Royal Astronomical Society. 314 (1): 175–182. arXiv: astro-ph/0001092 . Bibcode:2000MNRAS.314..175G. doi: 10.1046/j.1365-8711.2000.03342.x . S2CID   119433788.