LS 5039

{{Short description|Binary star system in the constellation Scutum}}

{{Sky|18|26|15.0568|-|14|50|54.242}}

{{Starbox begin}}

{{Starbox image

| image = 250px

| caption = A broad-band optical light curve for V479 Scuti, adapted from Sarty et al. (2011)

}}

{{Starbox observe

| epoch = J2000

| constell = Scutum

| ra = {{RA|18|26|15.0568}}{{cite journal|bibcode=2016A&A...595A...2G|doi=10.1051/0004-6361/201629512|arxiv=1609.04172|title=Gaia Data Release 1|journal=Astronomy & Astrophysics|volume=595|pages=A2|year=2016|author=Gaia Collaboration|s2cid=1828208}}

| dec = {{DEC|-14|50|54.242}}

| appmag_v = 11.27{{cite journal|author1=Zacharias, N.|title=The fourth US Naval Observatory CCD Astrograph Catalog (UCAC4)|journal=VizieR On-line Data Catalog|date=2012|bibcode=2012yCat.1322....0Z}}

}}

{{Starbox character

| class = {{nowrap|O(f)N6.5V + Black hole}}

}}

{{Starbox astrometry

| radial_v = 17.2 ± 0.7{{cite journal|doi=10.1111/j.1365-2966.2005.09617.x|bibcode=2005MNRAS.364..899C|arxiv=astro-ph/0507549|title=A possible black hole in the γ-ray microquasar LS 5039|journal=Monthly Notices of the Royal Astronomical Society|volume=364|issue=3|pages=899–908|year=2005|last1=Casares|first1=J|last2=Ribo|first2=M|last3=Ribas|first3=I|last4=Paredes|first4=J. M|last5=Marti|first5=J|last6=Herrero|first6=A|doi-access=free |s2cid=8393701}}

| prop_mo_ra = 6.826

| prop_mo_dec = −8.515

| dist_ly = {{val|8200|300}}

| dist_pc = {{val|2500|100}}

}}

{{Starbox orbit

| reference =

| period_unitless = 3.90603 ± 0.00017 d

| eccentricity = 0.31 ± 0.04

| inclination = 24.9 ± 2.8

| periarg = 226 ± 8

| periastron = {{nowrap|HJD 2451943.09 ± 0.10}}

| k1 = 19.4 ± 0.9

}}

{{Starbox detail

| source =

| component1 = O star

| mass = {{val|22.9|+3.4|-2.9}}

| radius = {{val|9.3|+0.7|-0.6}}

| luminosity = {{val|182000}}

| gravity = 3.85

| temperature = 39000

| rotational_velocity = 113

| component2 = Black hole

| mass2 = {{val|3.7|+1.3|-1.0}}

| radius_km2 = Probably 10.93

}}

{{Starbox catalog

| names = {{odlist|V=V479 Sct|2MASS=J18261505-1450542|TYC=5702-1197-1}}{{cite simbad|title=V* V479 Sct|access-date=2 May 2018}}

}}

{{Starbox reference

| Simbad = V479+Sct

}}

{{Starbox end}}

LS 5039 is a binary system in the constellation of Scutum. It has an apparent magnitude of 11.27, and it is about 8,200 light-years away.

LS 5039 consists of a massive O-type main-sequence star, and a compact object (likely a black hole) that emits HE (high energy) and VHE (very high energy) gamma rays. It is one of the only three known star systems of this kind, together with LS I +61 303 and PSR B1259-63. The two objects orbit each other every 3.9 days, along a moderately eccentric orbit. Additionally, it is one of the few massive X-ray binaries known to be associated with radio emission.{{cite journal|doi=10.1051/0004-6361/202141018|arxiv=2106.08865|title=MONOS: Multiplicity of Northern O-type Spectroscopic systems|year=2021|last1=Trigueros Páez|first1=E.|last2=Barbá|first2=R. H.|last3=Negueruela|first3=I.|last4=Maíz Apellániz|first4=J.|last5=Simón-Díaz|first5=S.|last6=Holgado|first6=G.|journal=Astronomy & Astrophysics|volume=655|pages=A4|s2cid=235446900}}