Epsilon Apodis

{{Short description|Star in the constellation Apus}}

{{Starbox begin

| name = ε Apodis

}}

{{Starbox image

| image=

{{Location mark

|image=Apus constellation map.svg|alt=|float=center|width=260

|label=|position=right

|mark=Red circle.svg|mark_width=10|mark_link=ε Apodis

|x=648|y=720

}}

|caption=Location of ε Apodis (circled)

}}

{{Starbox observe

| epoch = J2000

| ra = {{RA|14|22|23.16467}}

| dec = {{DEC|−80|06|32.2053}}

| appmag_v = 5.06

| constell = Apus

}}

{{Starbox character

| class = B3 V

| b-v = −0.121

| u-b = −0.610

| variable = γ Cas

}}

{{Starbox astrometry

| radial_v = +4.5{{±|4.2}}

| prop_mo_ra = −9.51

| prop_mo_dec = −14.34

| parallax = 5.06

| p_error = 0.22

| parallax_footnote =

| absmag_v = −1.41

}}

{{Starbox detail

| mass = {{val|6.15|0.71}}

| radius = 4.30{{±|0.09}}

| luminosity = 1,614

| temperature = 17,100{{±|171}}

| metal_fe = −0.02

| gravity = 3.50{{±|0.04}}

| rotational_velocity = 150{{±|3}}

| age_myr = 38.3{{±|4.4}}

}}

{{Starbox catalog

| names = {{odlist | B=ε Aps | CD=-79°559 | HD=124771 | HIP=70248 | HR=5336 | SAO=257142 }}

}}

{{Starbox reference

| Simbad=eps+Aps

}}

{{Starbox end}}

Epsilon Apodis is a star in the southern circumpolar constellation of Apus. Its identifier is a Bayer designation that is Latinized from ε Apodis, and abbreviated Eps Aps or ε Aps, respectively. This star has an apparent visual magnitude of 5.06, which is bright enough to be viewed from dark suburban skies. Based upon parallax measurements, it is at a distance of roughly {{Convert|640|ly|pc|abbr=off|lk=on}} from Earth. The star is drifting further away with a heliocentric radial velocity of +4.5 km/s.

File:EpsilonApsLightCurve.png for Epsilon Apodis, plotted from Hipparcos data]]

Based upon a stellar classification of B3 V, this is a massive, B-type main sequence star that is generating energy through the fusion of hydrogen at its core. Epsilon Apodis has more than six times the mass of the Sun and over four times the Sun's radius. It is radiating 1,614 times as much luminosity as the Sun from its photosphere at an effective temperature of 17,100 K. At this heat, it has a blue-white glow that is a characteristic of B-type stars.

Epsilon Apodis is spinning rapidly, with a projected rotational velocity of 150 km/s giving a lower bound for the azimuthal velocity along the equator. Epsilon Apodis is classified as a Gamma Cassiopeiae type variable star and its brightness varies between magnitudes 4.99 and 5.04.

Naming

In Chinese caused by adaptation of the European southern hemisphere constellations into the Chinese system, {{lang|zh|異雀}} ({{lang|zh-Latn|Yì Què}}), meaning Exotic Bird, refers to an asterism consisting of ε Apodis, ζ Apodis, ι Apodis, β Apodis, γ Apodis, δ Octantis, δ1 Apodis, η Apodis and α Apodis. Consequently, ε Apodis itself is known as {{lang|zh|異雀九}} ({{lang|zh-Latn|Yì Què jiǔ}}, {{langx|en|the Ninth Star of Exotic Bird}}.)

References

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