Omega2 Cygni

{{Starbox begin

| name = Omega² Cygni

}}

{{Starbox observe

| epoch = J2000.0

| equinox = J2000.0 (ICRS)

| constell = Cygnus

| ra = {{RA|20|31|18.81655}}

| dec = {{DEC|+49|13|13.0638}}

| appmag_v = {{Val|5.5292|0.0013}}

}}

{{Starbox character

| type = AGB

| class = M2 III

| b-v =

| u-b =

| r-i =

| variable =

}}

{{Starbox astrometry

| radial_v = {{Val|−64.15|0.20}}

| prop_mo_ra = +8.959

| prop_mo_dec = −32.092

| parallax = 7.1833

| p_error = 0.0675

| parallax_footnote =

| absmag_v = +0.00

}}

{{Starbox detail

| mass = 1.4

| radius = 45

| luminosity = 398

| temperature = 3,920

| gravity = 2.02

| metal_fe = −0.10

| rotational_velocity =

| age_myr =

}}

{{Starbox catalog

| names = ω² Cyg, 46 Cygni, BD+48°3154, HD 195774, HIP 101243, HR 7851, SAO 49741.

}}

{{Starbox reference

| Simbad = 46+Cyg

}}

Omega² Cygni, Latinized from ω² Cygni, is the Bayer designation for a solitary star in the northern constellation of Cygnus. It has an apparent visual magnitude of 5.5, which is faintly visible to the naked eye on a dark night. Based upon an annual parallax shift of {{val|7.18|ul=mas}}, it is located roughly 454 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.08 due to interstellar dust.

This is a red giant star on the asymptotic giant branch, with a stellar classification of M2 III. It is a suspected variable star, although the evidence is considered "doubtful or erroneous". If it does exist, the variability is small with an amplitude of 0.05 magnitude and a timescale of around 30 days. There is a 58.3% chance that this star is a member of the Hercules stream.

References

{{reflist|refs=

{{cite journal |bibcode=2024A&A...691A..98K |title=Transferring spectroscopic stellar labels to 217 million Gaia DR3 XP stars with SHBoost |last1=Khalatyan |first1=A. |last2=Anders |first2=F. |last3=Chiappini |first3=C. |last4=Queiroz |first4=A. B. A. |last5=Nepal |first5=S. |last6=Dal Ponte |first6=M. |last7=Jordi |first7=C. |last8=Guiglion |first8=G. |last9=Valentini |first9=M. |last10=Torralba Elipe |first10=G. |last11=Steinmetz |first11=M. |last12=Pantaleoni-González |first12=M. |last13=Malhotra |first13=S. |last14=Jiménez-Arranz |first14=Ó. |last15=Enke |first15=H. |last16=Casamiquela |first16=L. |last17=Ardèvol |first17=J. |journal=Astronomy and Astrophysics |date=2024 |volume=691 |pages=A98 |doi=10.1051/0004-6361/202451427 |arxiv=2407.06963 }}

{{cite journal |bibcode=2023ApJS..268....4F |title=Variability Catalog of Stars Observed during the TESS Prime Mission |last1=Fetherolf |first1=Tara |last2=Pepper |first2=Joshua |last3=Simpson |first3=Emilie |last4=Kane |first4=Stephen R. |last5=Močnik |first5=Teo |last6=English |first6=John Edward |last7=Antoci |first7=Victoria |last8=Huber |first8=Daniel |last9=Jenkins |first9=Jon M. |last10=Stassun |first10=Keivan |last11=Twicken |first11=Joseph D. |last12=Vanderspek |first12=Roland |last13=Winn |first13=Joshua N. |journal=The Astrophysical Journal Supplement Series |date=2023 |volume=268 |issue=1 |page=4 |doi=10.3847/1538-4365/acdee5 |doi-access=free |arxiv=2208.11721 }}

{{cite journal

| title=A photometric survey of suspected small-amplitude red variables

| last1=Percy | first1=John R. | last2=Fleming | first2=David E. B.

| journal=Publications of the Astronomical Society of the Pacific

| volume=104 | pages=96–100 | date=February 1992

| doi=10.1086/132963 | bibcode=1992PASP..104...96P | doi-access=free }}

{{cite journal

| last1=Eggen | first1=Olin J.

| title=Asymptotic giant branch stars near the sun

| journal=Astronomical Journal

| volume=104 | issue=1 | pages=275–313 |date=July 1992

| doi=10.1086/116239 | bibcode=1992AJ....104..275E }}