HD 119921

Last updated
HD 119921
Observation data
Epoch J2000       Equinox J2000
Constellation Centaurus
Right ascension 13h 46m 56.35149s [1]
Declination –36° 15 06.9563 [1]
Apparent magnitude  (V)5.15 [2]
Characteristics
Spectral type A0 V [3] [4] or B9.5 III-n [5]
Astrometry
Radial velocity (Rv)−9.8±2.8 [6]  km/s
Proper motion (μ)RA: −13.293 [1]   mas/yr
Dec.: −11.115 [1]   mas/yr
Parallax (π)7.7881 ± 0.2382  mas [1]
Distance 420 ± 10  ly
(128 ± 4  pc)
Absolute magnitude  (MV)0.93 [7]
Details
Luminosity 125.24 [8]   L
Temperature 8,801 [8]   K
Rotational velocity (v sin i)220 [9]  km/s
Age 337 [7]   Myr
Other designations
z Cen, CD−35°8995, FK5  3091, HD  119921, HIP  67244, HR  5174, SAO  204835, WDS J13469-3615A [10]
Database references
SIMBAD data

HD 119921 is a single, [4] white-hued star in the southern constellation of Centaurus. it has the Bayer designation z Centauri. This is faintly visible to the naked eye, having an apparent visual magnitude of 5.15. [2] It forms a wide double star with a faint, magnitude 12.50 visual companion, which is located at an angular separation of 27.20 as of 2010. [11] HD 119921 is moving closer to us with a heliocentric radial velocity of around −10 km/s, [6] and is currently located some 420±10  light year from the Sun. At that distance, the visual magnitude of this star is diminished by 0.15 from extinction due to interstellar dust. [7]

This is an A-type main-sequence star with a stellar classification of A0 V, per Houk (1979). [3] However, Gray & Garrison (1987) have it classed as B9.5 III-n, suggesting it is a more evolved giant star. [5] HD 119921 is spinning rapidly with a projected rotational velocity of 220 km/s. [9] The star is radiating around 125 times the Sun's luminosity from its photosphere at an effective temperature of 8,801 K. [8]

In 1983, Molaro et al. reported the presence of super-ionized elements (triple-ionized carbon and silicon) in the far ultraviolet spectrum of HD 119921. These anomalous features are not normally detected from a star in this temperature range. [12] Instead, these blue-shifted absorption features may originate in the local interstellar medium. [9]

Related Research Articles

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Lambda2 Tucanae is a solitary star in the southern constellation of Tucana. It is faintly visible to the naked eye with an apparent visual magnitude of +5.45. Based upon an annual parallax shift of 14.6 mas as seen from Earth, it is located around 223 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction factor of 0.09 due to interstellar dust.

<span class="mw-page-title-main">Eta Volantis</span> Star in the constellation Volans

Eta Volantis, Latinized from η Volantis, is a single star in the southern constellation of Volans. It has an apparent visual magnitude of 5.28, which is bright enough to be seen with the naked eye as a dim, white-hued star. Based upon parallax measurements, it is approximately 387 light years from the Sun. The star is moving further away from the Sun with a radial velocity of 20 km/s.

47 Aquarii, abbreviated 47 Aqr, is a star in the zodiac constellation of Aquarius. 47 Aquarii is its Flamsteed designation. It is a faint star but visible to the naked eye in good seeing conditions, having an apparent visual magnitude of 5.135. Based upon an annual parallax shift of 18.0 mas, it is located 181 light years away. At that distance, the visual magnitude of the star is diminished by an extinction of 0.088 due to interstellar dust. It is moving further from the Earth with a heliocentric radial velocity of +48 km/s.

56 Aquarii, abbreviated 56 Aqr, is a star in the constellation of Aquarius. 56 Aquarii is its Flamsteed designation. It is a sixth magnitude star, having an apparent visual magnitude of 6.36, and thus is a challenge to view with the naked eye. Based upon an annual parallax shift of 5.07 mas, it is located around 643 light years from the Earth. At that distance, the visual magnitude is diminished by an extinction of 0.12 due to interstellar dust. The star is moving closer with a heliocentric radial velocity of −28 km/s. It is a candidate runaway star showing a transverse peculiar velocity of 213.87 km/s.

10 Boötis is a suspected astrometric binary star system in the northern constellation of Boötes, located around 528 light years away from the Sun. It is visible to the naked eye under suitable viewing conditions as a dim, white-hued star with an apparent visual magnitude of 5.76. Its magnitude is diminished by an extinction of 0.17 due to interstellar dust. This system is moving away from the Earth with a heliocentric radial velocity of +6 km/s.

Xi2 Canis Majoris, which is Latinized from ξ2 Canis Majoris, is an astrometric binary star system in the southern constellation of Canis Major. With an apparent visual magnitude of +4.54, it is visible to the naked eye. Based upon an annual parallax shift of 8.35 mas, the system is approximately 390 light years distant from Earth. It is receding with a radial velocity of +26 km/s.

Delta<sup>3</sup> Canis Minoris Star in the constellation Canis Minor

Delta3 Canis Minoris, Latinized from δ3 Canis Minoris, is a solitary, white-hued star in the equatorial constellation of Canis Minor. Based upon a parallax of 4.46 mas as seen from Gaia spacecraft in its repeated orbits around the Sun, just beyond the Earth. This star is about 730 light years from the Solar System. At that distance, the visual magnitude of these stars is diminished by an extinction of more than 0.15 due to interstellar dust. With an apparent visual magnitude of +5.81, it is just bright enough to be faintly visible to the naked eye.

HD 129685 is a single star in the southern constellation of Centaurus. It is also known by its Bayer designation c2 Centauri, while HD 129685 is the star's identifier in the Henry Draper catalogue. This object has a white hue and is faintly visible to the naked eye with an apparent visual magnitude of +4.92. It is located at a distance of approximately 231 light years from the Sun based on parallax, and it has an absolute magnitude of 0.83. The star is drifting closer with a radial velocity of around −5 km/s.

<span class="mw-page-title-main">HD 125823</span> Star in the constellation Centaurus

HD 125823, also known as V761 Centauri or a Centauri, is a variable star in the constellation Centaurus. It is a blue-white star that is visible to the naked eye with a mean apparent visual magnitude of +4.41. The distance to this star is approximately 460 light years based on parallax measurements. It is a member of the Upper Centaurus–Lupus subgroup of the Scorpius–Centaurus association.

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

BX Boötis is a star in the northern constellation of Boötes. It is a dim star near the lower limit of visibility to the naked eye, having a nominal apparent visual magnitude of 6.35. Based upon an annual parallax shift of 10.81 mas, it is located 302 light years away. At that distance, the visual magnitude of the star is diminished by an extinction of 0.13 due to interstellar dust. It is moving closer with a heliocentric radial velocity of −11 km/s.

67 Aquarii is a star located 484 light years away from the Sun in the zodiac constellation of Aquarius. 67 Aquarii is its Flamsteed designation. It is a dim, blue-white hued star near the lower limit of visibility to the naked eye with an apparent visual magnitude of 6.40. At the distance of this star, its visual magnitude is diminished by an extinction of 0.11 due to interstellar dust. The position of this star near the ecliptic means it is subject to lunar eclipses.

<span class="mw-page-title-main">Eta Pyxidis</span> White-hued main sequence star in the constellation Pyxis

Eta Pyxidis (η Pyxidis) is a solitary, white-hued star in the southern constellation of Pyxis. It is faintly visible to the naked eye with an apparent visual magnitude of +5.27. Based upon an annual parallax shift of 14.07 mas as seen from Earth, this star is located around 232 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction factor of 0.07 due to interstellar dust.

HD 102350 is a single star in the constellation Centaurus. It has a yellow hue and is visible to the naked eye with an apparent visual magnitude of 4.11. The distance to this star is approximately 390 light years based on parallax, but it is drifting closer with a radial velocity of −3 km/s. It has an absolute magnitude of −1.51.

HD 34968 is a binary star system in the southern constellation Lepus. The combined apparent visual magnitude of 4.69 is bright enough to be visible to the naked eye. The distance to HD 34968 can be estimated from its annual parallax shift of 8.7 mas, yielding a range of 374 light years. It is moving further away from the Earth with a heliocentric radial velocity of 31 km/s, having come within 118.6 ly some 3,686,000 years ago.

HD 137058 is a star in the southern constellation of Lupus. Eggleton and Tokovinin (2008) list it as a single star, although Nitschelm and David (2011) noted it may be a double-lined spectroscopic binary. Its apparent visual magnitude is 4.60, which is bright enough to be visible to the naked eye. Based upon an annual parallax shift of 13.6 mas, it is located 240 light years away.

HD 146624 is a single, white-hued star in the southern zodiac constellation of Scorpius. It is faintly visible to the naked eye, having an apparent visual magnitude of 4.80. The distance to HD 146624 can be estimated from its annual parallax shift of 23.0 mas, yielding a separation of 142 light years. At that distance, the visual magnitude is reduced by an extinction of 0.17 due to interstellar dust. It is a member of the Beta Pictoris moving group, a set of ~12 million year old stars that share a common motion through space.

Theta Hydri, Latinized from θ Hydri, is the Bayer designation for a blue-white hued star in the southern constellation of Hydrus. It is faintly visible to the naked eye with an apparent visual magnitude of +5.53. Based upon an annual parallax shift of 6.50 mas as seen from Earth, is located approximately 502 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction of 0.10 due to interstellar dust. It is moving away from the Sun with a radial velocity of +12.3 km/s.

HD 63584 is a solitary star in the southern circumpolar constellation Volans. With an apparent magnitude of 6.15, it is barely visible to the naked eye under ideal conditions. The star is located 420 light years away based on parallax, but is drifting away with a radial velocity of 10.4 km/s.

<span class="mw-page-title-main">HD 118285</span> SPB star in the constellation Chamaeleon.

HD 118285, also known as HR 5115, is a variable star located in the southern circumpolar constellation Chamaeleon. DY Chamaeleontis is its variable star designation. It has an average apparent magnitude of 6.32, placing it near the limit for naked eye visibility. The object is located relatively far at a distance of 864 light years based on Gaia DR3 parallax measurements but is receding with a heliocentric radial velocity of 18 km/s. At its current distance, HD 118285's brightness is diminished by 0.58 magnitudes due to interstellar dust.

References

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