SS Ursae Minoris

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SS Ursae Minoris
SSUMiLightCurve.png
A visual band light curve for SS Ursae Minoris. The main plot shows a superoutburst, and the inset plot shows superhumps seen on April 8-9, 1998. Adapted from Kato et al. (1998) [1]
Observation data
Epoch J2000.0       Equinox J2000.0
Constellation Ursa Minor
Right ascension 15h 51m 22.3401s [2]
Declination +71° 45 11.8343 [2]
Characteristics
Variable type dwarf nova [3]
Astrometry
Proper motion (μ)RA: 13.085±0.080 [2]   mas/yr
Dec.: −12.260±0.088 [2]   mas/yr
Parallax (π)1.8871 ± 0.0497  mas [2]
Distance 1,730 ± 50  ly
(530 ± 10  pc)
Details
Other designations
Gaia DR2  1696309737421796352, 2MASS J15512233+7145118 [4]
Database references
SIMBAD data

SS Ursae Minoris is a cataclysmic variable star system in the constellation Ursa Minor. It was discovered visually and by its X-ray emissions separately in 1982 before they were understood to be coming from the same object. [5] It is classified as a SU Ursae Majoris variable subclass of dwarf nova in that it has both 'normal' outbursts of increased brightness as well as even brighter 'superoutbursts'. However, unlike other SU Ursae Majoris stars, the superoutbursts are of longer duration than the regular outbursts. [3]

The two stars orbit each other every 98 minutes. [3]

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<span class="mw-page-title-main">UX Ursae Majoris</span>

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<span class="mw-page-title-main">BZ Ursae Majoris</span> Dwarf Nova in the constellation Ursa Major

BZ Ursae Majoris is a dwarf nova star system in the northern circumpolar constellation of Ursa Major. It consists of a white dwarf primary in a close orbit with a red dwarf. The latter star is donating mass, which is accumulating in an accretion disk orbiting the white dwarf. The system is located at a distance of approximately 505 light years from the Sun based on parallax measurements.

<span class="mw-page-title-main">RZ Leonis Minoris</span> Variable star in the constellation Leo Minor

RZ Leonis Minoris is a cataclysmic variable star system in the northern constellation of Leo Minor. It undergoes frequent outbursts that vary in brightness from an apparent visual magnitude of 14.4 down to 16.8. Based on parallax measurements, this system is located at a distance of approximately 2,160 light years from the Sun.

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

SW Ursae Majoris is a cataclysmic binary star system in the northern circumpolar constellation of Ursa Major, abbreviated SW UMa. During quiescence it has an apparent visual magnitude of 16.5–17, which is too faint to be visible to the naked eye. Based on parallax measurements, it is located at a distance of approximately 526 light years from the Sun.

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

AE Ursae Majoris is a star in the northern circumpolar constellation of Ursa Major, abbreviated AE UMa. It is a variable star that ranges in brightness from a peak apparent visual magnitude of 10.86 down to 11.52. The distance to this star is approximately 2,400 light years based on parallax measurements.

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

DW Ursae Majoris is an eclipsing binary star system in the northern circumpolar constellation of Ursa Major, abbreviated DW UMa. It is a cataclysmic variable of the SX Sextanis type, consisting of a compact white dwarf that is accreting matter from an orbiting companion star. The brightness of this source ranges from an apparent visual magnitude of 13.6 down to magnitude 18, which is too faint to be viewed with the naked eye. The distance to this system is approximately 1,920 light years based on parallax measurements.

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

ER Ursae Majoris is a variable star in the northern circumpolar constellation of Ursa Major, abbreviated ER UMa. It is a prototype system for a subclass of SU Ursae Majoris dwarf novae. The system ranges in brightness from a peak apparent visual magnitude of 12.4 down to 15.2, which is too faint to be visible to the naked eye. The distance to this system, based on parallax measurements, is approximately 1,163 light years.

<span class="mw-page-title-main">CR Boötis</span> Star system in the constellation Boötes

CR Boötis is an interacting binary system in the northern constellation of Boötes, abbreviated CR Boo. It is one of the best-known AM Canum Venaticorum stars. The system varies widely in brightness, ranging in apparent visual magnitude from 13.6 down to 17.5. The distance to this system is approximately 1,150 light years from the Sun, based on parallax measurements.

References

  1. Kato, T.; Lipkin, Y.; Retter, A.; Leibowitz, E. (June 1998). "Observation of Superhumps in SS UMi". Information Bulletin on Variable Stars. 4602: 1. Bibcode:1998IBVS.4602....1K . Retrieved 27 April 2022.
  2. 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 . Gaia DR2 record for this source at VizieR.
  3. 1 2 3 Chen, J.-S.; Liu, X.-W.; Wei, M.-Z. (1991). "CCD photometry of the SU Ursae Majoris cataclysmic variable SS Ursae Minoris (PG 1551 + 719)". Astronomy and Astrophysics. 242 (2): 397–400. Bibcode:1991A&A...242..397C. ISSN   0004-6361.
  4. "V* SS UMi". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2019-10-07.
  5. Udalski, A. (1990). "SS Ursae Minoris: a Normal U Gem Type Dwarf Nova". Information Bulletin on Variable Stars. 3425 (3425): 1–4. Bibcode:1990IBVS.3425....1U.