Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Scorpius |
Right ascension | 16h 04m 10.1267s [1] |
Declination | −22° 34′ 45.5503″ [1] |
Characteristics | |
Evolutionary stage | M [2] |
Astrometry | |
Proper motion (μ) | RA: -11.544 [1] mas/yr Dec.: -24.892 [1] mas/yr |
Parallax (π) | 7.3908 ± 0.1944 mas [1] |
Distance | 440 ± 10 ly (135 ± 4 pc) |
Details | |
Mass | 0.161±0.028 [2] [3] M☉ |
Radius | 0.631±0.042 [3] R☉ |
Luminosity (bolometric) | 0.0273±0.0020 [2] L☉ |
Temperature | 2960±75 [2] K |
Rotation | 1.63 days [4] |
Age | 10 [5] Myr |
Other designations | |
Database references | |
SIMBAD | data |
EPIC 204376071 is an M-type star in the constellation of Scorpius. Parallax measurements by the Gaia space observatory put the star at a distance of about 440 light-years (130 parsecs ) from Earth. [2] [3] [5] It is likely a member of the Upper Sco association, and is young enough that it has not yet become a main-sequence star. [2]
Unusual light fluctuations of the star, including up to an 80% dimming in brightness (i.e., "single 80% deep occultation of 1-day duration"), were observed by astronomers. [3] [5] The unusual dimming was not only extremely deep, but also substantially asymmetric, with an egress about twice as long as the ingress. [4] Nonetheless, such an unusual dimming for EPIC 204376071 is much greater than the 22% dimming observed for Tabby's star. [6] [7] Several explanations have been presented to explain the unusual dimming of the EPIC 204376071 star: one, orbiting dust or small particles; or two, a "transient accretion event of dusty material near the corotation radius of the star". [3] The unusual lightcurve of the star is similar to the lightcurve of a candidate exoplanet, KIC 10403228 b, which may have been caused by a "tilted ring system" orbiting the planet. In the case of EPIC 204376071, an orbiting brown dwarf or large planet, with a ring system, could cause a similar lightcurve, according to the researchers. [5]
In astronomy, a light curve is a graph of the light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y-axis and with time on the x-axis. The light is usually in a particular frequency interval or band.
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319 Leona is a dark, carbonaceous asteroid in the outer regions of the asteroid belt. It was discovered on 8 October 1891, by French astronomer Auguste Charlois at Nice Observatory in France. On 12 December 2023, Leona passed in front of the bright star Betelgeuse and occulted it, which caused the star to briefly dim as seen from Central America, Europe, and east Asia. This occultation was expected to reveal the shape of Leona and the surface of Betelgeuse in high detail.
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38628 Huya ( hoo-YAH; provisional designation 2000 EB173) is a binary trans-Neptunian object located in the Kuiper belt, a region of icy objects orbiting beyond Neptune in the outer Solar System. Huya is classified as a plutino, a dynamical class of trans-Neptunian objects with orbits in a 3:2 orbital resonance with Neptune. It was discovered by the Quasar Equatorial Survey Team and was identified by Venezuelan astronomer Ignacio Ferrín in March 2000. It is named after Juyá, the mythological rain god of the Wayuu people native to South America.
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HD 45184 is a star in the southern constellation of Canis Major. It is a yellow-hued star near the lower limit of visibility to the naked eye with an apparent visual magnitude of 6.37. The star is located at a distance of 71.65 light years from the Sun based on parallax. It is drifting closer with a radial velocity of −3.8 km/s.
V1400 Centauri is a young, pre-main-sequence star that was eclipsed by a likely free-floating substellar object with a circumstellar disk or rings in April–May 2007. With an age around 20 million years, the star is about as massive as the Sun and is located in the constellation Centaurus at a distance of 451 light-years away from the Sun. V1400 Centauri is a member of Upper Centaurus–Lupus subgroup of the Scorpius–Centaurus association, a group of young, comoving stars close to the Sun.
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EPIC 204278916 is a pre-main-sequence star, about five million years old with a spectral type of M1, implying a red dwarf. It is part of the Upper Scorpius sub-group of the Scorpius–Centaurus association, and is in the constellation Scorpius. The star is approximately the size of the Sun at 0.97 R☉, but is only half its mass (0.50 M☉) and a fraction of its luminosity (0.15 L☉).
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