UU Aurigae

Last updated
UU Aurigae
Auriga constellation map.svg
Red circle.svg
Location of UU Aurgae (circled)
Observation data
Epoch J2000       Equinox J2000
Constellation Auriga
Right ascension 06h 36m 32.83710s [1]
Declination +38° 26′ 43.8190″ [1]
Apparent magnitude  (V)4.9–7.0 [2]
Characteristics
Spectral type C5,3-C7,4(N3) [2]
B−V color index 2.61
R−I color index 1.43
Variable type SRb [2]
Astrometry
Radial velocity (Rv)13.40 [3]  km/s
Proper motion (μ)RA: 0.500 [1]   mas/yr
Dec.: −19.758 [1]   mas/yr
Parallax (π)2.0387 ± 0.1661  mas [1]
Distance 341 [4]   pc
Absolute magnitude  (MV)−3.65 [5]
Details
Radius 370 [6]   R☉
Luminosity 16,443 [7]   L☉
Temperature 2,760 [7]   K
Other designations
GC 8581, SAO 59280, BD+38° 1539, HD 46687, HIP 31579, HR 2405 [8]
Database references
SIMBAD data

UU Aurigae is a carbon star in the constellation Auriga. It is approximately 341 parsecs (1,110 light-years ) from Earth. It is a variable star that is occasionally bright enough to be seen by the naked eye under excellent observing conditions.

Contents

Description

UU Aurigae in optical light UU Aurigae.jpg
UU Aurigae in optical light

John Birmingham observed the star from 1871 to 1875, and detected its variability. It was confirmed as a variable star by Thomas William Backhouse in 1905, based on observations from 1894 to 1904. It was given its variable star designation in 1912. [9] [10]

UU Aurigae is a carbon-rich asymptotic giant branch star. The spectral type listed in the General Catalogue of Variable Stars (GCVS) is C5,3-C7,4(N3). The N3 refers back to an older type of classification where carbon stars were given spectral types of N or R, although the numeric index was correlated more with the strength of the carbon chemistry rather than temperature. The C5 to C7 indicates various classifications using the newer Morgan-Keenan system where the numeric index corresponds better to the temperature of the star. C5 to C7 types are approximately equivalent to early-M stars. The second numeric index, 3 or 4 for UU Aurigae indicates the strength of the Swan bands in the spectrum, on a scale of 1 to 5. [11] Using the more modern revised Morgan-Keenan scheme, a spectral type of C-N5- C2 6- has been published, with the C-N5 indicating an N-type carbon star with a temperature index of 5-, and a Swan band strength of 6- on a scale of 1 to 8. [12]

A 28 year long visual band light curve for UU Aurigae, adapted from Howarth (2001) UUAurLightCurve.png
A 28 year long visual band light curve for UU Aurigae, adapted from Howarth (2001)

UU Aurigae is classified as a semiregular variable of type SRb, indicating it is a giant star with poorly defined variations. Its brightness varies from magnitude +4.9 to +7.0 in visual apparent magnitude. [2] The period is given in the GCVS as 441 days, but there is also a strong variation with a period of 235 days. [14] Using British Astronomical Association observations from 1971 to 1998, the periods are calculated as 439.4 and 233.1 days. [13]

The angular diameter of UU Aurigae has been measured at 12.07 ± 0.22 mas using very-long-baseline interferometry (VLBI). [15] Around the star is a shell of dust made up largely of amorphous carbon and silicon carbide (SiC), with the SiC appearing at three times the star's radius and the amorphous carbon at nine times its radius. Further out is a carbon-rich shell at 300 stellar radii and two oxygen-rich shells even further away. [16] UU Aurigae also has a bow shock 0.14 parsec wide, created by its motion through the interstellar medium. [4]

Related Research Articles

Tau<sup>4</sup> Serpentis Star in the constellation Serpens

Tau4 Serpentis, Latinized from τ4 Serpentis, is a variable M-type giant star in the constellation of Serpens, approximately 710 light-years from the Earth. Its brightness varies from magnitude 5.89 to 7.07, making it occasionally bright enough to be faintly visible to the naked eye under very good observing conditions.

<span class="mw-page-title-main">9 Aurigae</span> Multiple star system in the constellation Auriga

9 Aurigae is a star system in Auriga (constellation). It has an apparent magnitude of about 5, making it visible to the naked eye in many suburban skies. Parallax estimates made by the Hipparcos spacecraft put it at about 86 light-years from the solar system, although individual Gaia Data Release 3 parallaxes place all three components at 88 light years.

<span class="mw-page-title-main">R Andromedae</span> Star in the constellation Andromeda

R Andromedae is a Mira-type variable star in the constellation Andromeda. Its spectral class is type S because it shows absorption bands of zirconium monoxide (ZrO) in its spectrum. It was among the stars found by Paul Merrill to show absorption lines of the unstable element technetium, establishing that nucleosynthesis must be occurring in stars. The SH molecule was found for the first time outside earth in the atmosphere of this star. The star is losing mass due to stellar winds at a rate of 1.09×10−6M☉/yr.

<span class="mw-page-title-main">V Aquilae</span> Star in the constellation Aquila

V Aquilae is a carbon star and semiregular variable star in the constellation Aquila. It has an apparent magnitude which varies between 6.6 and 8.4 and is located around 400 parsecs (1,300 ly) away.

<span class="mw-page-title-main">DY Persei</span> Variable carbon star in the constellation Perseus

DY Persei is a variable star and carbon star in the Perseus constellation. At maximum it is 11th magnitude and at its faintest it drops to 16th magnitude. DY Persei is the prototype of the very rare DY Persei class of variables that pulsate like red variables but also fade from sight like R Coronae Borealis variables.

<span class="mw-page-title-main">NO Apodis</span> Star in the constellation Apus

NO Apodis is a solitary, red hued variable star located in the southern circumpolar constellation Apus. It has an average apparent magnitude of 5.86, allowing it to be faintly seen with the naked eye. The object is relatively far at a distance of 790 light years but is drifting closer with a heliocentric radial velocity −18.3 km/s.

<span class="mw-page-title-main">NO Aurigae</span> Star in the constellation Auriga

NO Aurigae is a pulsating variable star in the constellation Auriga. It is an unusually-luminous asymptotic giant branch star about 3,500 light years away. It is a 6th magnitude star faintly visible to the naked eye under very good observing conditions.

<span class="mw-page-title-main">TX Piscium</span> Carbon star visible to the naked eye in the constellation Pisces

TX Piscium is a variable red giant star in the constellation Pisces. It is amongst the reddest naked eye stars, with a significant reddish hue when seen in binoculars. It is approximately 800 light years from Earth. It is close to—and sometimes considered part of—the asterism on the western end of the constellation called the circlet of Pisces.

<span class="mw-page-title-main">SU Andromedae</span> Star in the constellation Andromeda

SU Andromedae is a carbon star in the constellation of Andromeda. It is a variable star classified as a slow irregular pulsating supergiant, and varies from an apparent visual magnitude of 8.5 at minimum brightness to a magnitude of 8.0 at maximum brightness with no clear period.

<span class="mw-page-title-main">WZ Cassiopeiae</span> Star in the constellation Cassiopeia

WZ Cassiopeiae is a deep red hued star in the northern constellation of Cassiopeia. It is a variable star with a magnitude that ranges from 6.3 down to 8.8, placing it near the limit of naked eye visibility at peak magnitude. The estimated distance to this star, as determined from its annual parallax shift of 2.1 mas, is about 1,540 light years. It is moving closer to the Earth with a heliocentric radial velocity of −34 km/s.

<span class="mw-page-title-main">U Camelopardalis</span> Star in the constellation Camelopardalis

U Camelopardalis is a semiregular variable star in the constellation Camelopardalis. Based on parallax measurements made by the Hipparcos spacecraft, it is located about 3,000 light-years away from the Earth. Its apparent visual magnitude is about 8, which is dim enough that it cannot be seen with the unaided eye.

<span class="mw-page-title-main">Delta Coronae Borealis</span> Yellow giant star in the constellation Corona Borealis

Delta Coronae Borealis, Latinized from δ Coronae Borealis, is a variable star in the constellation Corona Borealis. Its apparent magnitude varies regularly between apparent magnitude 4.57 and 4.69, and it is around 170 light-years distant.

<span class="mw-page-title-main">83 Ursae Majoris</span> Candidate binary star system in the constellation Ursa Major

83 Ursae Majoris is a candidate binary star system in the northern circumpolar constellation of Ursa Major. It is a semiregular variable star, and it has been given the variable star designation IQ Ursae Majoris. It ranges in brightness from apparent visual magnitude 4.69 to 4.75, making it visible to the naked eye under good observing conditions. Percy and Au (1994) identified it as a small amplitude red variable with an irregular behavior, having a characteristic time scale of 20 days. Based upon an annual parallax shift of 5.60 mas, it is located roughly 580 light years from the Sun. The system is moving closer with a heliocentric radial velocity of −18.6 km/s.

<span class="mw-page-title-main">Y Centauri</span> Variable star in the constellation Centaurus

Y Centauri or Y Cen is a semiregular variable star in the constellation of Centaurus.

<span class="mw-page-title-main">Gliese 908</span> Star in the constellation Pisces

Gliese 908 is a red dwarf star, located in constellation Pisces at 19.3 light-years from Earth. It is a BY Draconis variable star with a variable star designation of BR Piscium. Its apparent magnitude varies between magnitude 8.93 and magnitude 9.03 as a result of starspots and varying chromospheric activity.

<span class="mw-page-title-main">UZ Pyxidis</span> Star in the constellation Pyxis

UZ Pyxidis is a semiregular variable star in the constellation Pyxis. It is located about 3,600 light-years away from the Earth.

<span class="mw-page-title-main">Y Lyncis</span> Variable star in the constellation Lynx

Y Lyncis is a semiregular variable star in the constellation Lynx. It is an asymptotic giant branch star of spectral type M6S, with a luminosity class of Ib, indicating a supergiant luminosity. It is around 1,160 light years away. Y Lyncis ranges in brightness from magnitude 6.2 to 8.9. When it is at its brightest, it very faintly visible to the naked eye under excellent observing conditions.

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

RW Cygni is a semiregular variable star in the constellation Cygnus, about a degree east of 2nd magnitude γ Cygni. Its apparent magnitude varies between 8.05 and 9.70 and its spectral type between M3 and M4.

<span class="mw-page-title-main">6 Geminorum</span> Red supergiant star in the constellation Gemini

6 Geminorum is a variable star in the zodiac constellation of Gemini, located roughly 5,800 light years away from the Sun. It has the variable star designation BU Geminorum; 6 Geminorum is the Flamsteed designation. At its brightest this reddish hued star is barely visible to the naked eye but is readily visible with binoculars, found southeast of M 35, just to the south of WY Geminorum. It is moving further from the Earth with a heliocentric radial velocity of +27 km/s. The star is a member of the Gemini OB1 association.

<span class="mw-page-title-main">R Puppis</span> Variable star in the constellation Puppis

R Puppis is a variable star in the constellation Puppis. It is a rare yellow hypergiant and a candidate member of the open cluster NGC 2439. It is also an MK spectral standard for the class G2 0-Ia.

References

  1. 1 2 3 4 5 Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics . 649: A1. arXiv: 2012.01533 . Bibcode:2021A&A...649A...1G. doi: 10.1051/0004-6361/202039657 . S2CID   227254300. (Erratum:  doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  2. 1 2 3 4 Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
  3. ↑ Gontcharov, G. A (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv: 1606.08053 . Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID   119231169.
  4. 1 2 Cox, N. L. J; Kerschbaum, F; Van Marle, A.-J; Decin, L; Ladjal, D; Mayer, A; Groenewegen, M. A. T; Van Eck, S; Royer, P; Ottensamer, R; Ueta, T; Jorissen, A; Mecina, M; Meliani, Z; Luntzer, A; Blommaert, J. A. D. L; Posch, Th; Vandenbussche, B; Waelkens, C (2012). "A far-infrared survey of bow shocks and detached shells around AGB stars and red supergiants". Astronomy & Astrophysics. 537: A35. arXiv: 1110.5486 . Bibcode:2012A&A...537A..35C. doi:10.1051/0004-6361/201117910. S2CID   56041336.
  5. ↑ Alksnis, A; Balklavs, A; Dzervitis, U; Eglitis, I (1998). "Absolute magnitudes of carbon stars from HIPPARCOS parallaxes". Astronomy and Astrophysics. 338: 209. Bibcode:1998A&A...338..209A.
  6. ↑ Luttermoser, Donald G.; Brown, Alexander (1992). "A VLA 3.6 centimeter survey of N-type carbon stars". Astrophysical Journal. 384: 634. Bibcode:1992ApJ...384..634L. doi:10.1086/170905.
  7. 1 2 Bergeat, J; Knapik, A; Rutily, B (2002). "Carbon-rich giants in the HR diagram and their luminosity function". Astronomy and Astrophysics. 390 (3): 967. Bibcode:2002A&A...390..967B. doi: 10.1051/0004-6361:20020525 .
  8. ↑ "V* UU Aur". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 6 February 2018.
  9. ↑ Dunér; Hartwig; Müller (June 1912). "Benennung von neu entdeckten veränderlichen Sternen". Astronomische Nachrichten. 191 (19): 341. Bibcode:1912AN....191..341.. doi:10.1002/asna.19121911902 . Retrieved 30 November 2024.
  10. ↑ Backhouse, Thomas William (1905). Observations of variable stars. Sunderland: Hills & co. p. 48. Bibcode:1905ovs..book.....B . Retrieved 30 November 2024.
  11. ↑ Keenan, P. C. (1993). "Revised MK Spectral Classification of the Red Carbon Stars". Publications of the Astronomical Society of the Pacific . 105: 905. Bibcode:1993PASP..105..905K. doi: 10.1086/133252 .
  12. ↑ Barnbaum, Cecilia; Stone, Remington P. S; Keenan, Philip C (1996). "A Moderate-Resolution Spectral Atlas of Carbon Stars: R, J, N, CH, and Barium Stars". Astrophysical Journal Supplement. 105: 419. Bibcode:1996ApJS..105..419B. doi:10.1086/192323.
  13. 1 2 Howarth, J. J. (June 2001). "The semiregular variable UU Aurigae - analysis in adversity?". Journal of the British Astronomical Association. 111: 150–152. Bibcode:2001JBAA..111..150H . Retrieved 1 November 2021.
  14. ↑ Kiss, L. L; Szatmáry, K; Cadmus, R. R; Mattei, J. A (1999). "Multiperiodicity in semiregular variables. I. General properties". Astronomy and Astrophysics. 346: 542. arXiv: astro-ph/9904128 . Bibcode:1999A&A...346..542K.
  15. ↑ Quirrenbach, A; Mozurkewich, D; Hummel, C. A; Buscher, D. F; Armstrong, J. T (1994). "Angular diameters of the carbon stars UU Aurigae, Y Canum Venaticorum, and TX PISCIUM from optical long-baseline interferometry". Astronomy and Astrophysics. 285: 541. Bibcode:1994A&A...285..541Q.
  16. ↑ Bagnulo, S; Skinner, C. J; Doyle, J. G; Camphens, M (1997). "Carbon stars with detached dust shells: The circumstellar envelope of UU Aurigae". Astronomy and Astrophysics. 321: 605. Bibcode:1997A&A...321..605B.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.