19 Sextantis

{{Starbox begin

| name = 19 Sextantis

}}

{{Starbox image

| image =

{{Location mark

| image = Sextans constellation map.svg

| float = center | width = 260 | position = right

| mark = Red circle.svg | mark_width = 6 | mark_link = 19 Sextantis

| x = 490 | y = 334

}}

| caption = Location of 19 Sex on the map (circled)

}}

{{Starbox observe

| epoch = J2000.0 (ICRS)

| constell = Sextans

| ra = {{RA|10|12|48.36462}}

| dec = {{DEC|+04|36|52.8378}}

| appmag_v = 5.78{{±|0.01}}

}}

{{Starbox character

| type = red giant branch

| class = K1 III or K0 III

| b-v = +1.18

| u-b = +1.11

}}

{{Starbox astrometry

| radial_v = 31.80{{±|0.21}}

| parallax = 6.3184

| p_error = 0.0625

| parallax_footnote =

| prop_mo_ra = −50.538

| prop_mo_dec = −6.118

| pm_footnote =

| absmag_v =

}}

{{Starbox detail

| mass = 0.88{{±|0.08|0.03}}

| radius = 23.13{{±|1.17}}

| luminosity = 241{{±|4|5}}

| gravity =

| temperature = 4,576{{±|123}}

| metal_fe = −0.53

| rotational_velocity = 2.5{{±|0.8}}

| age_gyr = 7.94{{±|1.83|0.70}}

}}

{{Starbox catalog

| names = {{odlist|F = 19 Sex|Gould = 34 G. Sextantis|AG = +04°1386|BD = +05°2301|GC = 14022|HD = 88547|HIP = 50027|HR = 4004|SAO = 118164|TIC = 277696329}}

}}

{{Starbox reference

| Simbad = *19+Sex

}}

19 Sextantis (HD 88547; HR 4004; 34 G. Sextantis), or simply 19 Sex, is a solitary star located in the equatorial constellation Sextans. It is faintly visible to the naked eye as an orange-hued point of light with an apparent magnitude of 5.78. Gaia DR3 parallax measurements imply a distance of 516 light-years and it is currently receding with a heliocentric radial velocity of {{val|31.8|ul=km/s}}. At its current distance, 19 Sex's brightness is diminished by an interstellar extinction of 0.17 magnitudes.

19 Sex has a stellar classification of K1 III, indicating that it is an evolved K-type giant star that has ceased hydrogen fusion at it core and it has left the main sequence. It has also been given a slightly hotter class of K0 III. Stellar evolution models from Stock et al. (2018) model it to be a red giant branch star (100% chance) that is currently fusing a hydrogen shell around an inert helium core. It has 88% the mass of the Sun but at the age of 7.94 billion years, it has expanded to 23.13 times the radius of the Sun. It radiates 241 times the luminosity of the Sun from its photosphere at an effective temperature of {{val|4576|ul=K|fmt=commas}}. 19 Sex is metal deficient with an iron abundance of [Fe/H] = −0.53 or 29.5% of the Sun's and it spins modestly with a projected rotational velocity of {{val|2.5|ul=km/s}}.

References

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}}

Category:K-type giants