HIP 70849

HIP 70849
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Lupus
Right ascension 14h 29m 18.56436s[1]
Declination −46° 27′ 49.7378″[1]
Apparent magnitude (V) 10.36[2]
Characteristics
Spectral type K7Vk[3]
Apparent magnitude (B) 11.787[2]
Apparent magnitude (J) 7.639±0.023[2]
Apparent magnitude (H) 7.006±0.061[2]
Apparent magnitude (K) 6.790±0.027[2]
B−V color index 1.427±0.019[2]
Variable type 8.50[2]
Astrometry
Radial velocity (Rv)−0.134±0.0013[4] km/s
Proper motion (μ) RA: −44.051±0.017 mas/yr[1]
Dec.: −201.577±0.020 mas/yr[1]
Parallax (π)41.4618 ± 0.0175 mas[1]
Distance78.66 ± 0.03 ly
(24.12 ± 0.01 pc)
Absolute magnitude (MV)8.5[2]
Details
Mass0.63±0.03[5]
0.76±0.07[6] M☉
Radius0.62±0.02[5] R☉
Luminosity (bolometric)0.0892±0.0005[5] L☉
Surface gravity (log g)3.70±0.09[6] cgs
Temperature4,103±25[6] K
Metallicity [Fe/H]0.00±0.03[6] dex
Rotation41.2 d[5]
Rotational velocity (v sin i)1.93 km/s[5]
0.30±0.30[6] km/s
Age3.6±0.15[5] Gyr
Other designations
NSV 6678, CD−45°9206, GJ 550.3, HIP 70849, PPM 760399, LTT 5717, NLTT 37446[7]
Database references
SIMBADdata
Exoplanet Archivedata

HIP 70849 is a star with two non-stellar companions in the southern constellation Lupus. It is a 10th magnitude star, making it too faint to be visible to the naked eye.[2] The system is located at a distance of 78.7 light-years from the Sun based on parallax measurements.[1]

This is a K-type main-sequence star with a stellar classification of K7Vk,[3] where the 'k' indicates interstellar absorption features in the spectrum. The star is magnetically active with a 10.1±1.4 yr starspot cycle. It appears about 3.6 billion years old and the light emission shows a 41.2 day periodicity, which is likely the rotation period.[5] This star, which resembles a brighter red dwarf, is smaller and less massive than the Sun. It is radiating just 9%[5] of the luminosity of the Sun from its photosphere at an effective temperature of 4,103 K.[6]

In 2009, a gas giant planet was found in orbit around it.[8] Designated HIP 70849 b, it has 4.5 times the mass of Jupiter and takes more than 3000 days to orbit at a semimajor axis of 3.99 AU, with a high eccentricity.[9] There is also a T4.5 brown dwarf companion orbiting ~9000AU from HIP 70849.[10][11]

The HIP 70849 planetary system[9]
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(days) 		Eccentricity Inclination Radius
b 4.5+0.4
−0.3 MJ 		3.99+0.06
−0.07 		3649±18 0.65+0.02
−0.01 		96±16° —
  1. ^ a b c d e Cite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
  2. ^ a b c d e f g h i Cite error: The named reference Anderson_Francis_2012 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Gray_et_al_2006 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference Soubiran_et_al_2018 was invoked but never defined (see the help page).
  5. ^ a b c d e f g h Cite error: The named reference Zurlo_et_al_2018 was invoked but never defined (see the help page).
  6. ^ a b c d e f Cite error: The named reference Sousa_et_al_2018 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Ségransan2011 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference Philipot2023 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Lodieu2014 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Šubjak2022 was invoked but never defined (see the help page).