42 Leonis Minoris

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42 Leonis Minoris
Leo Minor constellation map.svg
Red circle.svg
Location of 42 Leo Minoris (circled)
Observation data
Epoch J2000       Equinox J2000
Constellation Leo Minor
Right ascension 10h 45m 51.8947s [1]
Declination +30° 40 56.307 [1]
Apparent magnitude  (V)5.35±0.01 [2]
Characteristics
Spectral type B9 V [3]
U−B color index −0.16 [4]
B−V color index −0.06 [4]
Astrometry
Radial velocity (Rv)12±3.7 [5]  km/s
Proper motion (μ)RA: −20.344  mas/yr [1]
Dec.: −38.234  mas/yr [1]
Parallax (π)7.915 ± 0.0813  mas
Distance 412 ± 4  ly
(126 ± 1  pc)
Absolute magnitude  (MV)+0.02 [6]
Details
Mass 2.77±0.36 [7]   M
Radius 3.29±0.11 [7]   R
Luminosity 107 [8]   L
Surface gravity (log g)4±0.2 [9]   cgs
Temperature 10,703±206 [7]   K
Rotational velocity (v sin i)145 [10]  km/s
Age 69+199
59
[9]   Myr
Other designations
42 LMi, AG+30°1079, BD+31°2180, FK5  407, GC  14798, HD  93152, HIP  52638, HR  4203, SAO  62236
Database references
SIMBAD data

42 Leonis Minoris (42 LMi) is a solitary, [11] bluish-white hued star located in the northern constellation Leo Minor. It has a visual apparent magnitude of 5.35, [2] allowing it to be faintly seen with the naked eye. Parallax measurements place it at a distance of 412 light years. [1] The object has a heliocentric radial velocity of 12  km/s , [5] indicating that it is drifting away from the Solar System.

42 LMi has a general stellar classification of B9 V, [3] indicating that it is an ordinary B-type main-sequence star. However, Cowley et al. (1969) gave a slightly cooler class of A1 Vn, [12] indicating that it is instead an A-type main-sequence star with 'nebulous' (broad) absorption lines due to rapid rotation. Nevertheless, it has 2.77 times the mass of the Sun and a radius of 3.3  R . [7] It radiates at 107 times the luminosity of the Sun [8] from its photosphere at an effective temperature of 10,703  K . [7] Its high luminosity and slightly enlarged diameter suggests that the object might be evolved. Like most hot stars, 42 LMi spins rapidly with a projected rotational velocity of 145  km/s . [10]

There are two optical companions located near this star. BD+31°2181 is a 7th magnitude K2 giant star separated 146 away along a position angle of 174° . [13] An 8th magnitude companion has been detected at a distance of over 400  arcseconds along a position angle of 92° . [13] Both have no relation to 42 LMi and is just moving with it by coincidence.

An X-ray emission with a luminosity of 278.2×1020  W has been detected around the object. A-type stars are not expected to emmit X-rays, so it must be coming from an unseen companion. [14]

Related Research Articles

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HD 85725, also known as HR 3916, is a yellow hued star located in the southern constellation Antlia. It has an apparent magnitude of 6.29, placing it near the limit for naked eye visibility. The object is relatively close at a distance of 176 light-years, but is receding with a heliocentric radial velocity of 61.6 km/s.

HD 27274, also known as Gliese 167, is a solitary, orange hued star located in the southern constellation Dorado. It has an apparent magnitude of 7.63, making it readily visible in binoculars, but not to the naked eye. Based on parallax measurements from the Gaia spacecraft, the star is known to be located 42.5 light-years away from the Solar System However, it is drifting closer with a heliocentric radial velocity of −23 km/s. At its current distance, HD 27274 is dimmed down by 0.05 magnitudes due to interstellar dust.

μ1 Chamaeleontis, Latinized as Mu1 Chamaeleontis, is a single star in the southern circumpolar constellation Chamaeleon. It is dimly visible to the naked eye with an apparent visual magnitude of 5.53. Based upon parallax measurements, it is located approximately 403 light-years away from the Sun. The radial velocity is poorly constrained, but it appears to be drifting further away at the rate of about 16 km/s

HD 203842 is a solitary star in the constellation Equuleus. With an apparent magnitude of 6.32, it's barely visible to the naked eye under ideal conditions. The star is located 327 light-years based on parallax, but is drifting closer with a heliocentric radial velocity of −33 km/s. HD 203842 is part of the Hyades Stream, which is not related to the Hyades Cluster.

HD 97413 is a binary star located in the southern constellation Centaurus. The system has a combined magnitude of 6.27, placing it near the limit for naked eye visibility. Based on parallax measurements from the Gaia spacecraft, the system is located 320 light years away from the Solar System.

<span class="mw-page-title-main">HD 90132</span> Solitary White-hued star and high proper motion star

HD 90132 is a solitary white hued star located in the southern constellation Antlia. It has an apparent magnitude of 5.33, making it one of the brighter members of this generally faint constellation. The star is relatively close at a distance of 135 light years but is receding with a heliocentric radial velocity of 17 km/s.

<span class="mw-page-title-main">HD 70514</span> Red giant star in the constellation Volans

HD 70514, also known as HR 3280, is a solitary, orange hued star located in the southern circumpolar constellation Volans, the flying fish. It has an apparent magnitude of 5.06, making it one of the brighter members of this generally faint constellation. Based on parallax measurements from the Gaia spacecraft, the star is estimated to be 298 light years distant. It appears that its distance to the Solar System isn't changing, having a heliocentric radial velocity of 0 km/s. Eggen (1994) lists it as a member of the thin disk population.

HD 26764 is a solitary star located in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.19, making it faintly to the naked eye if seen under ideal conditions. The star is currently situated at a distance of 266 light years but is drifting closer with a heliocentric radial velocity of 3.0 km/s, which is poorly constrained.

HD 27022, also known as HR 1327, is a star located in the northern circumpolar constellation Camelopardalis. The object has also been designated as 20 H. Camelopardalis, but is not commonly used in modern times. It has an apparent magnitude of 5.27, allowing it to be faintly visible to the naked eye. Based on parallax measurements from Gaia DR3, the star has been estimated to be 347 light years away. It appears to be approaching the Solar System, having a heliocentric radial velocity of −19.5 km/s.

HD 194012 is a star in the equatorial constellation Delphinus. It has an apparent magnitude of 6.15, making it visible to the naked eye under ideal conditions. The star is relatively close at a distance of only 85 light years but is receding with a heliocentric radial velocity of 4.5 km/s.

HD 89571 is a binary star located in the northern circumpolar constellation Camelopardalis. It is faintly visible to the naked eye with a combined apparent magnitude of 5.51 and is estimated to be 142 light years away from the Solar System. However, it is receding with a heliocentric radial velocity of 3.5 km/s.

HD 68375 is a solitary star in the northern circumpolar constellation Camelopardalis. It is faintly visible to the naked eye with an apparent magnitude of 5.54 and is estimated to be 289 light years distant. However, it is receding with a heliocentric radial velocity of 4.33 km/s.

HD 221420 is a likely binary star system in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.81, allowing it to be faintly seen with the naked eye. The object is relatively close at a distance of 102 light years but is receding with a heliocentric radial velocity of 26.5 km/s.

19 Leonis Minoris is a spectroscopic binary located in the northern constellation Leo Minor. It has an apparent magnitude of 5.1, making it one of the brighter members of the constellation. The system is relatively close at a distance of 94 light years but is drifitng closer with a heliocentric radial velocity of 8.6 km/s.

HD 183552, also known as HR 7411, is a probable spectroscopic binary located in the southern constellation Telescopium. The system has a combined apparent magnitude of 5.74, allowing it to be faintly visible to the naked eye. Based on parallax measurements from the Gaia spacecraft, it is estimated to be 337 light years distant. The value is horribly constrained, but it appears to receding with a radial velocity of 14 km/s.

HD 26670, also known as HR 1305, is a star located in the northern circumpolar constellation of Camelopardalis, the giraffe. The object has been designated as 26 H. Camelopardalis, but is not commonly used in modern times. It has an apparent magnitude of 5.70, allowing it to be faintly visible to the naked eye. Based on parallax measurements from Gaia DR3, the object is estimated to be 491 light years away from the Solar System. It appears to be slowly receding with a heliocentric radial velocity of 0.4 km/s.

HD 50885, also known as HR 2581, is a star located in the northern circumpolar constellation Camelopardalis, the giraffe. It has an apparent magnitude of 5.69, making it faintly visible to the naked eye if viewed under ideal conditions. Based on parallax measurements from Gaia DR3, the object is estimated to be 513 light years distant. It appears to be approaching the Solar System with a heliocentric radial velocity of −17.8 km/s.

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<span class="mw-page-title-main">8 Leonis Minoris</span> Suspected variable; M-type giant

8 Leonis Minoris is a solitary, red hued star located in the northern constellation Leo Minor. It has an apparent magnitude 5.37, making it faintly visible to the naked eye. Based on parallax measurements from the Gaia satellite, the object is estimated to be 492 light years distant. It is receding with a heliocentric radial velocity of 40 km/s. At its current distance, 8 LMi is diminshed by 0.12 magnitudes due to interstellar dust.

References

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