HR 8442

{{Short description|Spectroscopic binary star in the constellation Cepheus}}

{{Starbox begin

| name = HR 8442

}}

{{Starbox observe

| epoch = J2000.0

| constell = Cepheus

| ra = {{RA|22|07|09.634}}

| dec = {{DEC|+58|50|26.58}}

| appmag_v = 6.32

}}

{{Starbox character

| class = G8.6 III

| r-i =

| v-r =

| b-v = 0.88

| u-b = 0.63

| variable =

}}

{{Starbox astrometry

| radial_v = {{val|−7.37|0.03}}

| prop_mo_ra = {{val|−16.09|0.41}}

| prop_mo_dec = {{val|−22.30|0.41}}

| parallax = 4.80

| p_error = 0.46

| parallax_footnote =

| absmag_v = {{val|−0.3|0.2}}

}}

{{Starbox orbit

| reference =

| primary = HR 8442A

| name = HR 8442B

| period_unitless = {{val|737.4|0.4}} days

| eccentricity = {{val|0.308|0.007}}

| node =

| periastron = {{val|54113.3|2.1}}

| periarg = {{val|61.9|1.3}}

| k1 = {{val|5.55|0.04}}

| k2 =

}}

{{Starbox detail

| mass = 2.97

| radius =

| luminosity =

| gravity =

| temperature = {{val|5261|40}}

| metal_fe =

| rotation =

| rotational_velocity =

| age_gyr = 0.35

}}

{{Starbox catalog

| names = {{odlist|HD=210220|HIP=109190|HR=8442|BD=+58 2393|FK5=3770|SAO=34072}}

}}

{{Starbox reference

| Simbad = HD+210220

}}

HR 8442 is a spectroscopic binary star in the constellation Cepheus. The primary is a G type giant star while the secondary's spectral type is unknown.

The spectroscopic binary nature of the star was first noticed by Jose Renan de Medeiros and Michel Mayor using radial velocity measurements from the Coravel spectrometer at Haute-Provence Observatory. Roger Griffin then placed the star on his observing program at Cambridge Observatory leading to an orbital solution being published in 2015.

References

{{Reflist|refs=

{{cite journal | title=UBV photometry of 550 F, G and K type stars | last1=Argue | first1=A. N. | journal=Monthly Notices of the Royal Astronomical Society | volume=133 | issue=4 | pages=175–493 | year=1966 | bibcode=1966MNRAS.133..475A | doi=10.1093/mnras/133.4.475 | doi-access=free }}

{{cite journal | title=The rotational break for G giants | last1=Gray | first1=David F. | journal=Astrophysical Journal | volume=347 | pages=1021–1029 | year=1989 | bibcode=1989ApJ...347.1021G | doi=10.1086/168192 | doi-access=free }}

{{cite journal | title=Spectroscopic binary orbits from photoelectric radial velocities. Paper 241: HR 1884, HD 174103, HD 182563, and HR 8442, with a note on zeta Cephei | last1=Griffin | first1=R. F. | journal=The Observatory | volume=135 | pages=71–95 | year=2015 | bibcode=2015Obs...135...71G }}

{{cite journal | title=Abundances in the Local Region. I. G and K Giants | last1=Luck | first1=R. Earle | journal=Astronomical Journal | volume=150 | issue=3 | at=88 | year=2015 | bibcode=2015AJ....150...88L | doi=10.1088/0004-6256/150/3/88 |arxiv = 1507.01466 | s2cid=118505114 }}

{{cite journal | title=A catalog of rotational and radial velocities for evolved stars | url=http://aas.aanda.org/articles/aas/full/1999/18/ds1674/ds1674.html | last1=de Medeiros | first1=J. R. | last2=Mayor | first2=M. | journal=Astronomy and Astrophysics Supplement | volume=139 | issue=3 | pages=433–460 | year=1999 | bibcode=1999A&AS..139..433D | doi=10.1051/aas:1999401 | arxiv=astro-ph/0608248 }}

{{cite journal | title=Validation of the new Hipparcos reduction | url=http://www.aanda.org/articles/aa/full/2007/41/aa8357-07/aa8357-07.html | last1=van Leeuwen | first1=F. | journal=Astronomy and Astrophysics | volume=474 | issue=2 | pages=653–664 | year=2007 | arxiv=0708.1752 | bibcode=2007A&A...474..653V | doi=10.1051/0004-6361:20078357 | s2cid=18759600 }} [http://webviz.u-strasbg.fr/viz-bin/VizieR-5?-out.add=.&-source=I/311/hip2&recno=108821 Vizier catalog entry ]

}}

Category:Cepheus (constellation)

Category:Durchmusterung objects

210220

8442

109190

Category:Spectroscopic binaries

Category:G-type giants