4 Aquilae

{{Starbox begin

| name = 4 Aquilae

}}

{{Starbox observe

| epoch = J2000

| constell = Aquila

| ra = {{RA|18|44|49.93813}}

| dec = {{DEC|+02|03|36.1381}}

| appmag_v = 5.02

}}

{{Starbox character

| type =

| class = B9 V

| b-v = {{Val|−0.055|0.016}}

| u-b =

| variable =

}}

{{Starbox astrometry

| radial_v = {{Val|−13.0|4.2}}

| prop_mo_ra = +9.347

| prop_mo_dec = −14.719

| parallax = 6.7299

| p_error = 0.2433

| parallax_footnote =

| absmag_v = −0.75

}}

{{Starbox detail

| source =

| mass = {{Val|3.60|0.06}}

| radius = 3.00

| luminosity = {{Val|294|20.4|20.9}}

| temperature = {{Val|10965|50|51|fmt=commas}}

| metal_fe =

| gravity = {{Val|3.46|0.10}}

| rotational_velocity = 259

| age_myr =

}}

{{Starbox catalog

| names = {{odlist | F=4 Aql | BD=+01°3766 | HD=173370 | HIP=91975 | HR=7040 | SAO=123879 | AG=+02 2306 | GC=25652 }}

}}

{{Starbox reference

| Simbad = 4+Aql

}}

4 Aquilae, abbreviated 4 Aql, is a single, white-hued star in the equatorial constellation of Aquila. 4 Aquilae is the Flamsteed designation. It has an apparent visual magnitude of 5.02, making it a faint star visible to the naked eye. The distance to 4 Aql can be estimated from its annual parallax shift of {{Val|6.7|ul=mas}}, yielding an estimated range of around 480 light years. It is moving closer to the Earth with a heliocentric radial velocity of −13 km/s.

This is a B-type main-sequence star with a stellar classification of B9 V. It was classed as a Be star by Arne Sletteback in 1982, indicating it has ionized circumstellar gas. The star is spinning rapidly, showing a projected rotational velocity of 259 km/s, and is being viewed almost equator-on. It has 3.6 times the mass of the Sun and 3 times the Sun's radius. The star is radiating 294 times the Sun's luminosity from its photosphere at an effective temperature of 10,965 K.

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}}

Category:B-type main-sequence stars

Category:Be stars

Category:Aquila (constellation)

Category:Durchmusterung objects