Qatar-3#Qatar-3b
{{Short description|Star in the constellation Andromeda}}
{{Starbox begin}}
{{Starbox observe
| constell = Andromeda
| epoch = J2000.0
| dec = {{DEC|+36|12|46.7749}}
}}
{{Starbox character
| type = subgiant
| variable = planetary transit
}}
{{Starbox astrometry
| radial_v = {{val|-2.32|13.31}}
| parallax = 1.5818
| p_error = 0.0218
| absmag_v =
}}
{{Starbox detail
| mass = {{val|1.145|0.064}}
| radius = {{val|1.272|0.14}}
| gravity = {{val|4.28|0.05}}
| luminosity = {{val|1.90|0.46}}
| temperature = {{val|5991|64|fmt=commas}}
| metal_fe = {{val|−0.041|0.081}}
| rotational_velocity = {{val|10.4|0.5}}
| age_myr = {{val|310|1}}
| rotation = 6.31
}}
{{Starbox catalog
| names = {{odlist | Gaia DR3=2878641361300809856 }}
}}
{{Starbox reference|Simbad=Qatar+3}}
{{Starbox end
}}
Qatar-3 is a 12th magnitude star located in the northern constellation Andromeda. It is host to a transiting planet. With a radial velocity of 10.99 km/s, it is drifting away from the Solar System, and is currently located 2,400 light years away based on its annual parallax.
Properties
This star is a G-type star with 14.5% more mass than the Sun, and 27.2% larger. It has a luminosity of almost two times that of the Sun, and has effective temperature of 5,991 K, which gives it a yellow hue. Qatar-3 is also a metal poor star that has a similar metallicity to the Sun, and has a rapid rotation rate of 10.4 km/s. This means it takes Qatar-3 6.31 days to complete a full rotation, while the Sun takes almost a month to rotate.
Planetary system{{anchor|Qatar-3b}}
In 2016, the Qatar Exoplanet Survey discovered a planet around Qatar-3, Qatar-4, and Qatar-5, which was led by an international team in Qatar. Qatar-3b is a massive planet, with 4.31 times the mass of Jupiter, and has a similar radius to the latter. With a density of {{val|4.0|u=g/cm3}}, this is one of the densest planets discovered. With an effective temperature of {{val|1,681|fmt=commas|ul=K}}, it is a scorching planet.{{Cite web|title=Astronomers discover three 'Qatar' exoplanets|url=https://phys.org/news/2016-06-astronomers-qatar-exoplanets.html|access-date=2021-03-26|website=phys.org|language=en}}
{{Orbitbox planet begin}}
{{Orbitbox planet|exoplanet=b|mass={{val|4.31|0.47}}|radius={{val|1.096|0.14}}|inclination={{val|86.8|2.0}}|eccentricity=0|period=2.5079204|semimajor={{val|fmt=none|0.03783|0.00069}}}}
{{Orbitbox end}}
{{Infobox planet
| extrasolarplanet = yes
| name = Qatar-3b
| image =
| image_alt =
| caption =
| apsis = astron
| discoverer = Alsubai et al. 2019
| discovery_site =
| discovered = 2016
| discovery_method = Transit
| alt_names =
| periastron =
| apoastron =
| semimajor = {{val|fmt=none|0.03783|0.00069|u=au}}
| inclination = {{val|86.8|2.0|u=°}}
| long_periastron =
| time_periastron =
| semi-amplitude = {{val|587|58|u=m/s}}
| mass = {{val|4.31|0.47|u=jupiter mass}}
| mean_radius = {{val|1.096|0.14|u=jupiter radius}}
| density = {{val|4.0|1.2|u=g/cm3}}
| surface_gravity =
| single_temperature = {{val|fmt=commas|1681|84|u=K}}
}}
Qatar-3b
Qatar-3b is a hot Jupiter.{{Cite web|title=Qatar-3|url=https://www.universeguide.com/star/qatar3|access-date=2019-12-27|website=Universe Guide|date=15 September 2018 |language=en}} It orbits its star every 2.5 days. It was discovered in 2016 by the Qatar Exoplanet Survey (QES).{{Cite web|url=http://phys.org/news/2016-06-astronomers-qatar-exoplanets.html|title = Astronomers discover three 'Qatar' exoplanets}} This planet was discovered by QES along with Qatar-4b and Qatar-5b. The light curves of the planet's respective host stars have been observed as well during the survey, along with their stellar properties.
=Orbit=
This planet is another typical hot Jupiter. It orbits very close to its star with a period of 2 days, 12 hours, 11 minutes, and 24 seconds.{{Cite web|title=Convert a Decimal Time Amount to Days, Hours, Minutes and Second|url=https://www.spikevm.com/calculators/conversions/decimal-day-hrs-min-sec.php|access-date=2021-03-25|website=www.spikevm.com}} This corresponds with an orbital distance of about 0.04 AU, which is 10 times closer to its star than Mercury is to the Sun. With an eccentricity of 0, this suggests that Qatar-3b is on a perfectly circular orbit.
=Physical properties=
Qatar-3b is a massive planet, with 4.31 times the mass of Jupiter, but a similar radius. With a density of 4.0 g cm−3, this is one of the densest planets discovered. With an effective temperature of 1,681 K, it is a scorched planet.{{cite journal | title=Qatar Exoplanet Survey: Qatar-3b, Qatar-4b, and Qatar-5b | last1=Alsubai | first1=Khalid | last2=Mislis | first2=Dimitris | last3=Tsvetanov | first3=Zlatan I. | last4=Latham | first4=David W. | last5=Bieryla | first5=Allyson | last6=Buchhave | first6=Lars A. | last7=Esquerdo | first7=Gilbert A. | last8=Bramich | first8=D. M. | last9=Pyrzas | first9=Stylianos | last10=Vilchez | first10=Nicolas P. E. | last11=Mancini | first11=Luigi | last12=Southworth | first12=John | last13=Evans | first13=Daniel F. | last14=Henning | first14=Thomas | last15=Ciceri | first15=Simona | display-authors=1 | journal=The Astronomical Journal | volume=153 | issue=4 | at=200 | year=2017 | arxiv=1606.06882 | bibcode=2017AJ....153..200A | doi=10.3847/1538-3881/aa6340 | s2cid=119214858 | doi-access=free }}