20 Aquarii

{{Starbox begin

| name = 20 Aquarii

}}

{{Starbox observe

| epoch = J2000

| constell = Aquarius

| ra = {{RA|21|24|51.67515}}

| dec = {{DEC|−03|23|54.0858}}

| appmag_v = 6.38

}}

{{Starbox character

| class = F0 V or F0 III

| b-v = {{Val|0.334|0.002}}

| u-b =

| variable =

}}

{{Starbox astrometry

| radial_v = {{Val|−23.2|2.9}}

| prop_mo_ra = −6.125

| prop_mo_dec = −49.515

| parallax = 15.3426

| p_error = 0.0730

| parallax_footnote =

| absmag_v = 2.37

}}

{{Starbox detail

| source =

| mass = 1.52

| radius =

| luminosity = 9.38

| temperature = {{Val|7314|249|fmt=commas}}

| metal_fe =

| gravity = 4.17

| rotational_velocity = 92

| age_myr = 761

}}

{{Starbox catalog

| names = {{odlist | F=20 Aqr | BD=−05°5444 | HD=203843 | HIP=105729 | HR=8192 | SAO=145376 | GC=29976 }}

}}

{{Starbox reference

| Simbad = 20+Aqr

}}

20 Aquarii, abbreviated 20 Aqr, is a star in the constellation Aquarius. 20 Aquarii is the Flamsteed designation. It is a dim star with an apparent visual magnitude of 6.38. Based upon an annual parallax shift of {{Val|15.34|ul=mas}}, it is located 213 light years away but is moving closer to the Earth with a heliocentric radial velocity of −23 km/s. The star is predicted to come to within {{Convert|34.61|pc|ly|disp=out|abbr=off|sigfig=2}} in around 1.9 million years.

This is an F-type main-sequence star with a stellar classification of F0 V. (Cowley and Fraquelli [1974] had given it a class of F0 III.) It is a suspected chemically peculiar Am star showing metallic lines. It is 761 million years old with a high projected rotational velocity of 92 km/s. The star has 1.52 times the mass of the Sun and is radiating 9 times the Sun's luminosity from its photosphere at an effective temperature of about 7,314 K.

References

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