74 Cygni

{{short description|Binary star system in the constellation Cygnus}}

{{Starbox begin

| name = 74 Cygni

}}

{{Starbox observe

| epoch = J2000

| constell = Cygnus

| ra = {{RA|21|36|56.97051}}

| dec = {{DEC|+40|25|48.5818}}

| appmag_v = 5.04

}}

{{Starbox character

| type = main sequence

| class = A3 Vn

| b-v = {{Val|0.198|0.003}}

| u-b =

| variable =

}}

{{Starbox astrometry

| radial_v = {{Val|5.3|2.9}}

| prop_mo_ra = +2.270

| prop_mo_dec = +18.399

| parallax = 13.0909

| p_error = 0.2893

| parallax_footnote =

| absmag_v = 0.95

}}

{{Starbox orbit

| reference =

| period_unitless = {{Val|574.632|9.4158|u=days}}

| axis_unitless = {{Val|8.56|0.91|u=mas}}

| eccentricity = {{Val|0.5349|0.1066}}

| inclination = {{Val|102.1|4.39}}

| node = 18.92

| periastron = {{Val|8579.5387|18.6175}}

| periarg = {{Val|306.56|14.01}}

}}

{{Starbox detail

| source =

| component1 = 74 Cyg A

| mass = {{val|1.83|0.29}}

| radius = {{val|3.68|0.13}}

| luminosity = {{val|44|2}}

| temperature = {{Val|7757|120|fmt=commas}}

| gravity = {{val|3.57|0.08}}

| metal_fe =

| rotational_velocity = 201

| age_myr = 606

}}

{{Starbox catalog

| names = {{odlist | F=74 Cyg | BD=+39°4612 | FK5=811 | HD=205835 | HIP=106711 | HR=8266 | SAO=51101 | WDS=J21369+4025 }}

}}

{{Starbox reference

| Simbad=74+Cyg

}}

{{Starbox end}}

74 Cygni is a visual binary star system in the northern constellation Cygnus, located around 249 light years distant from the Sun. It is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of 5.04. The pair orbit each other with a period of {{Convert|574.632|days|years|2|disp=out|abbr=off}} and an eccentricity of 0.5. The system is a source of X-ray emission, which is most likely coming from the secondary component.

The primary component is an A-type main-sequence star with a stellar classification of A3 Vn; a star that is fusing its core hydrogen. The 'n' suffix indicates "nebulous" absorption lines due to rapid rotation, with the star having a projected rotational velocity of 201 km/s. The high rate of spin is giving the star an oblate shape with an equatorial bulge that is 8% larger than the polar radius. The star has 1.83 times the mass of the Sun, 3.68 times the Sun's radius, and is radiating 44 times the Sun's luminosity from its photosphere at an effective temperature of about 7,757 K.

References

{{reflist|refs=

{{cite simbad | title=74 Cyg | access-date=2019-01-20 }}

{{Cite Gaia DR2|1966070246674941824}}

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}}

{{Stars of Cygnus}}

Category:A-type main-sequence stars

Category:Binary stars

Category:Cygnus (constellation)

Category:Durchmusterung objects

Cygni, 74

205835

106711

8266