Delta Circini

{{Short description|Variable star in the constellation Circinus}}

{{Starbox begin

| name = Delta Circini

}}

{{Starbox image

| image=

{{Location mark

|image=Circinus constellation map.svg

|float=center

|alt=

|label=

|position=right

|width=260

|mark=Red circle.svg

|mark_width=10

|mark_link=δ Circini

|x=361|y=522

}}

|caption=Location of δ Cir (circled)

}}

{{Starbox observe

| epoch = J2000.0

| constell = Circinus

| ra = {{RA|15|16|56.89591}}

| dec = {{DEC|-60|57|26.1201}}

| appmag_v = 5.09{{cite journal|bibcode= 2002yCat.2237....0D |title= VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system |journal= CDS/ADC Collection of Electronic Catalogues |volume= 2237 |last1= Ducati |first1= J. R. |year= 2002 }} {{nowrap|(5.05 - 5.20)}}

}}

{{Starbox character

| class = O7.5III(f) {{nowrap|(O8IV + O9.5V + B0.5V({{cite journal|bibcode=2001ApJ...548..889P|title=Tomographic Separation of Composite Spectra. VII. The Physical Properties of the Massive Triple System HD 135240 (δ Circini)|journal=The Astrophysical Journal|volume=548|issue=2|pages=889|last1=Penny|first1=Laura R.|last2=Seyle|first2=Debra|last3=Gies|first3=Douglas R.|last4=Harvin|first4=James A.|last5=Bagnuolo|first5=William G.|last6=Thaller|first6=M. L.|last7=Fullerton|first7=A. W.|last8=Kaper|first8=L.|year=2001|doi=10.1086/319031|doi-access=free}})}}

| b-v = −0.06

| u-b = −0.88

| variable = Eclipsing and ellipsoidal

}}

{{Starbox astrometry

| radial_v = −17.80{{cite journal|bibcode=2004A&A...424..727P|title=SB9: The ninth catalogue of spectroscopic binary orbits|journal=Astronomy and Astrophysics|volume=424|issue=2|pages=727–732|last1=Pourbaix|first1=D.|last2=Tokovinin|first2=A. A.|last3=Batten|first3=A. H.|last4=Fekel|first4=F. C.|last5=Hartkopf|first5=W. I.|last6=Levato|first6=H.|last7=Morrell|first7=N. I.|last8=Torres|first8=G.|last9=Udry|first9=S.|year=2004|doi=10.1051/0004-6361:20041213|arxiv = astro-ph/0406573 |s2cid=119387088}}

| prop_mo_ra = −4.085

| prop_mo_dec = −3.758

| parallax = 1.4345

| p_error = 0.1231

| parallax_footnote={{cite Gaia DR3|5875491419647525248}}

| dist_pc =

| absmag_v =

}}

{{Starbox orbit

| reference =

| primary = Aa

| name = Ab

| period =

| period_unitless = 3.902463 days

| axis =

| axis_unitless = {{solar radius|34.7}}

| eccentricity = 0.068

| inclination = 75.81

| node =

| periastron =

| periarg =

| periarg_primary =

| k1 = 156.8

| k2 = 280.4

}}

{{Starbox orbit|no_heading=y

| reference =

| primary = Aab

| name = Ac

| period =

| period_unitless = 1,644 days

| axis = 3.87

| axis_unitless =

| eccentricity = 0.415

| inclination = 87.7

| node =

| periastron =

| periarg =

| periarg_primary =

| k1 = 23.6

| k2 =

}}

{{Starbox detail

| component1=Aa

| mass={{val|20.00|0.50}}{{cite journal |title=High-mass pulsators in eclipsing binaries observed using TESS |author1=Southworth, John |author2=Bowman, Dominic M. |journal=Monthly Notices of the Royal Astronomical Society |volume=513 |issue=3 |pages=3191–3209 |date=July 2022 |bibcode=2022MNRAS.513.3191S |doi=10.1093/mnras/stac875 |doi-access=free |arxiv=2203.15365 }}

| radius={{val|9.256|0.091}}

| luminosity={{val|fmt=commas|153,000|27,000|23,000}}

| temperature=37,500

| metal=

| gravity=3.806

| rotational_velocity={{val|150|9}}

| age_myr=

}}

{{Starbox detail|no_heading=y

| component1=Ab

| mass={{val|11.41|0.24}}

| radius={{val|5.326|0.091}}

| luminosity={{val|fmt=commas|21,827|5,026|4,085}}

| temperature={{val|fmt=commas|30,400|400}}

| metal=

| gravity={{val|4.043|0.014}}

| rotational_velocity={{val|141|230}}

| age_myr=

}}

{{Starbox detail|no_heading=y

| component1=Ac

| mass=18.7

| radius=

| luminosity=17,000

| temperature=28,000

| metal=

| gravity=4.2

| rotation=

| age_myr=

}}

{{Starbox catalog

| names = δ Cir, CD−60°5539, SAO 253084, HD 135240, HR 5664, HIP 74778, WDS J15169-6057

}}

{{Starbox reference

|Simbad=del+Cir

}}

{{Starbox end}}

Delta Circini (δ Cir), is a multiple star system located in the constellation Circinus. Delta Circini is also known as HR 5664, and HD 135240. The system has a combined apparent visual magnitude of +5.09, and is located at a distance of about 700 pc (2,300ly) from the Sun.