Editing Sagitta (section)

====Bright stars====
Ptolemy saw the constellation's brightest star [[Gamma Sagittae]] as marking the arrow's head,<ref name="ridpathsag">{{cite web |last=Ridpath |first=Ian |author-link=Ian Ridpath |title=Sagitta |url=http://www.ianridpath.com/startales/sagitta.html |access-date=22 May 2015 |work=Star Tales}}</ref> while Bayer saw Gamma, Eta, and Theta as depicting the arrow's shaft.<ref name=wagman/> Gamma Sagittae is a [[red giant]] of spectral type M0&nbsp;III,<ref name=strassmeier>{{cite journal|bibcode=2018A&A...612A..45S|title=PEPSI deep spectra. II. Gaia benchmark stars and other M-K standards|journal=[[Astronomy and Astrophysics]]|volume=612|pages=A45|last1=Strassmeier|first1=K. G. |last2=Ilyin|first2=I.|last3=Weber|first3=M.|year=2018|arxiv=1712.06967|doi=10.1051/0004-6361/201731633|s2cid=119244142}}</ref> and magnitude 3.47. It lies at a distance of {{val|258|4|ul=light-years}} from Earth.<ref name="vanLeeuwen2007">{{cite journal | first=F. | last=van Leeuwen | title=Validation of the New Hipparcos Reduction | journal=[[Astronomy and Astrophysics]] | volume=474 | issue=2 | pages=653–664 | date=2007 | bibcode=2007A&A...474..653V | doi=10.1051/0004-6361:20078357 | arxiv=0708.1752| s2cid=18759600 }}</ref> With around 90% of the Sun's mass,<ref name=stock>{{cite journal
 | title=Precise radial velocities of giant stars. X. Bayesian stellar parameters and evolutionary stages for 372 giant stars from the Lick planet search
 | last1=Stock | first1=Stephan | last2=Reffert | first2=Sabine
 | last3=Quirrenbach | first3=Andreas | last4=Hauschildt | first4=P.
 | journal=Astronomy and Astrophysics
 | volume=616 | pages=A33 | year=2018
 | bibcode=2018A&A...616A..33S | arxiv=1805.04094
 | doi=10.1051/0004-6361/201833111 | s2cid=119361866 }}</ref><ref name=Neilson2008>{{cite journal
 | last1=Neilson | first1=Hilding R. | last2=Lester | first2=John B.
 | title=Determining parameters of cool giant stars by modeling spectrophotometric and interferometric observations using the SAtlas program
 | journal=Astronomy and Astrophysics
 | volume=490 | issue=2 | pages=807–10 | date=2008
 | bibcode=2008A&A...490..807N | arxiv=0809.1875
 | doi=10.1051/0004-6361:200810627 | s2cid=1586125 }}</ref> it has a radius 54 times that of the Sun and is 575 times as bright. It is most likely on the [[red-giant branch]] of its [[stellar evolution|evolutionary]] lifespan, having exhausted its core hydrogen and now burning it in a surrounding shell.<ref name=stock/><!-- cites previous 3 sentences -->

[[Delta Sagittae]] is the second-brightest star in the constellation and is a binary. Delta and Zeta depicted the spike according to Bayer.{{sfn|Wagman|2003|p=515}} The Delta Sagittae system is composed of a [[red supergiant]] of spectral type M2&nbsp;II<ref name=Eaton/> that has 3.9 times the Sun's mass and 152 times its radius and a blue-white B9.5V<ref name=Eaton/> [[main sequence]] star that is 2.9 times as massive as the Sun. The two orbit each other every ten years.<ref name=Eaton>{{cite journal|title=Winds and accretion in delta Sagittae|author=Eaton, Joel A.|author2=Hartkopf, William I.|author3=McAlister, Harold A.|author4=Mason, Brian D.|journal=[[Astronomical Journal]]|volume=109|number=4|pages=1856–1866|date=1995|bibcode=1995AJ....109.1856E|doi=10.1086/117412}}</ref> [[Zeta Sagittae]] is a triple star system,<ref name=Eggleton2008>{{citation
 | last1=Eggleton | first1=P. P. | last2=Tokovinin | first2=A. A.
 | title=A catalogue of multiplicity among bright stellar systems
 | journal=Monthly Notices of the Royal Astronomical Society
 | volume=389 | issue=2 | pages=869–879 | date=September 2008
 | bibcode=2008MNRAS.389..869E | doi=10.1111/j.1365-2966.2008.13596.x
 | doi-access=free | arxiv=0806.2878 | s2cid=14878976 | postscript=. }}</ref> approximately {{val|326|u=light-years}} from Earth. The primary and secondary are A-type stars.<ref name=Christy1969>{{citation
 | last1=Christy | first1=James W. | last2=Walker | first2=R. L. Jr.
 | title=MK Classification of 142 Visual Binaries | postscript=.
 | journal=Publications of the Astronomical Society of the Pacific
 | volume=81 | issue=482 | page=643 | date=October 1969
 | doi=10.1086/128831 | bibcode=1969PASP...81..643C | doi-access=free }}</ref><ref name=Cowley1969>{{citation | display-authors=1
 | last1=Cowley | first1=A. | last2=Cowley | first2=C.
 | last3=Jaschek | first3=M. | last4=Jaschek | first4=C.
 | title=A study of the bright A stars. I. A catalogue of spectral classifications
 | journal=Astronomical Journal | postscript=.
 | volume=74 | pages=375–406 | date=April 1969
 | doi=10.1086/110819 | bibcode=1969AJ.....74..375C }}</ref>

In his ''Uranometria'', Bayer depicted Alpha, [[Beta Sagittae|Beta]], and [[Epsilon Sagittae]] as the fins of the arrow.{{sfn|Wagman|2003|p=515}} Also known as Sham, Alpha is a yellow [[bright giant]] star of [[Stellar classification|spectral class]] G1&nbsp;II with an [[apparent magnitude]] of 4.38, which lies at a distance of {{val|382|8|u=light-years}} from Earth.<ref name=Gaia-DR2alpha>{{cite DR2|1824277055360974720}}</ref> Four times as massive as the Sun, it has swollen and brightened to 21&nbsp;times the Sun's radius and 340&nbsp;times its [[luminosity]].<ref name="vanBelle2009" /><ref name=kalersham>{{cite web| first=James B. | last=Kaler | title=Sham | work=Stars | publisher=University of Illinois | url=http://stars.astro.illinois.edu/sow/sham.html | access-date=22 May 2015}}</ref> Also of magnitude 4.38, Beta is a G-type [[giant star|giant]] located {{val|420|10|u=light-years}} distant from Earth.<ref name=Gaia-DR2beta>{{cite DR2|1823991938300446336}}</ref> Estimated to be around 129&nbsp;million years old, it is 4.33&nbsp;times as massive as the Sun,<ref name=Liu2014>{{cite journal | title=The Lithium Abundances of a Large Sample of Red Giants | display-authors=1 | last1=Liu | first1=Y. J. | last2=Tan | first2=K. F. | last3=Wang | first3=L. | last4=Zhao | first4=G. | last5=Sato | first5=Bun'ei | last6=Takeda | first6=Y. | last7=Li | first7=H. N. | journal=[[The Astrophysical Journal]] | arxiv=1404.1687 | volume=785 | issue=2 | id=94 | page=12 | date=2014 | doi=10.1088/0004-637X/785/2/94 | bibcode=2014ApJ...785...94L | s2cid=119226316 }}</ref> and has expanded to roughly 27 times its radius.<ref name=vanBelle2009>{{cite journal | title=Supergiant temperatures and linear radii from near-infrared interferometry | journal=[[Monthly Notices of the Royal Astronomical Society]] | volume=394 | issue=4 | page=1925 | year=2009 | last1=Van Belle | first1=G. T. | last2=Creech-Eakman | first2=M. J. | last3=Hart | first3=A. | bibcode=2009MNRAS.394.1925V | arxiv=0811.4239 | doi=10.1111/j.1365-2966.2008.14146.x | doi-access=free | s2cid=118372600 }}</ref> Epsilon Sagittae is a [[double star]] whose component stars can be seen in a small telescope.<ref name="turnleft">{{cite book|last=Consolmagno|first=Guy |title=Turn Left at Orion: Hundreds of Night Sky Objects to See in a Home Telescope – and How to Find Them|publisher=[[Cambridge University Press]]|location=Cambridge, United Kingdom|year=2019 | orig-date=1989 |page=138 |isbn=978-1-108-45756-9|url=https://books.google.com/books?id=D2JjDwAAQBAJ&pg=PA139}}</ref> With an apparent magnitude of 5.77,<ref name=Mason2014/> the main star is a 331-million-year-old yellow giant of spectral type G8&nbsp;III around 3.09&nbsp;times as massive as the Sun,<ref name=takeda14>{{cite journal | title=Spectroscopic study on the beryllium abundances of red giant stars | journal=[[Publications of the Astronomical Society of Japan]] | volume=66 | issue=5 | page=91 | year=2014 | last1=Takeda | first1=Yoichi | last2=Tajitsu | first2=Akito | doi=10.1093/pasj/psu066 | bibcode=2014PASJ...66...91T | arxiv=1406.7066| s2cid=119283677 }}</ref> that has swollen to {{val|18.37|0.65|0.88}} its radius.<ref name="GaiaDR2epsilon"/> It is {{val|580|10|u=light-years}} distant.<ref name="GaiaDR2epsilon">{{Cite DR2|4321830946398475776}}</ref> The visual companion of magnitude 8.35 is 87.4&nbsp;[[arcseconds]] distant,<ref name=Mason2014>{{cite journal| last1=Mason | first1=B. D. | last2=Wycoff | first2=G. L. | last3=Hartkopf | first3=W. I. | last4=Douglass | first4=G. G. | last5=Worley | first5=C. E. | title=The Washington Visual Double Star Catalog | journal=[[Nature (journal)|Nature]] | year=2014 | volume=122 | issue=6 | page=3466 | bibcode=2001AJ....122.3466M | doi = 10.1086/323920 | doi-access=free }}</ref> but is an unrelated [[blue supergiant]] around {{val|7000|fmt=commas|u=light-years}} distant from Earth.<ref name="GaiaDR2comp">{{cite DR2|4321830980758181760}}</ref>

[[Eta Sagittae]] is an orange giant of spectral class K2&nbsp;III<ref name=Roman1952>{{citation
 | title=The Spectra of the Bright Stars of Types F5-K5
 | last=Roman | first=Nancy G. | postscript=.
 | journal=Astrophysical Journal
 | volume=116 | page=122 | date=July 1952
 | doi=10.1086/145598 | bibcode=1952ApJ...116..122R | doi-access=free }}</ref> with a magnitude of 5.09.<ref name=Argue1966>{{citation
 | last=Argue | first=A. N. | postscript=.
 | title=UBV photometry of 550 F, G and K type stars
 | journal=[[Monthly Notices of the Royal Astronomical Society]]
 | volume=133 | pages=475–493 | year=1966
 | issue=4 | bibcode=1966MNRAS.133..475A | doi=10.1093/mnras/133.4.475| doi-access=free}}</ref> Located {{val|155.9|0.9|u=light-years}} from Earth, it has a 61.1% chance of being a member of the [[Hyades (star cluster)|Hyades]]–[[Pleiades]] stream of stars that share a [[Stellar kinematics|common motion through space]].<ref name=Famaey2005>{{cite journal| last1=Famaey | first1=B. | last2=Jorissen | first2=A. | last3=Luri | first3=X. | last4=Mayor | first4=M. | last5=Udry | first5=S. | last6=Dejonghe | first6=H. | last7=Turon | first7=C. | title=Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters | journal=[[Astronomy and Astrophysics]] | volume=430 | pages=165–186 | date=2005 | doi=10.1051/0004-6361:20041272 | bibcode=2005A&A...430..165F | arxiv=astro-ph/0409579 | s2cid=17804304 }}</ref> [[Theta Sagittae]] is a double star system, with components 12 arcseconds apart visible in a small telescope.<ref name="turnleft"/> At magnitude 6.5, the brighter is a yellow-white main sequence star of spectral type F3&nbsp;V,<ref name="abt1985">{{cite journal |last=Abt |first=Helmut A. |title=Visual multiples. VIII. 1000 MK types |journal=The Astrophysical Journal Supplement Series |date=1985 |bibcode= 1985ApJS...59...95A |volume=59 |pages=95–112 |doi=10.1086/191064|doi-access=free }}</ref> located {{val|146.1|0.2|u=light-years}} from Earth.<ref name=Gaia-DR2tet1>{{cite DR2|1829590548393010560}}</ref> The 8.8-magnitude fainter companion is a main sequence star of spectral type G5&nbsp;V. A 7.4-magnitude orange giant of spectral type K2&nbsp;III is also visible {{val|91|ul="}} from the binary pair,<ref name="abt1985"/> located {{val|842|9|u=light-years}} away.<ref name=Gaia-DR2tet2>{{cite DR2|1829590410954063744}}</ref>