SWEEPS-10

From Wikipedia, the free encyclopedia

**SWEEPS J175902.00−291323.7**
Observation data Epoch J2000
Constellation (pronunciation)	Sagittarius
Right ascension	17h 59m 02.00s
Declination	-29° 13' 23.7"'
Apparent magnitude (V)	26.23
Astrometry
Distance	6500 ly (2000 pc)
Details
Mass	0.44 M_☉
Radius	0.41 R_☉
Database references
SIMBAD	data

SWEEPS-10 is, as of June 2007, the planet candidate with the shortest orbital period yet found. It completes an orbit of its star (designated SWEEPS J175902.00−291323.7) in just 10 hours. Located only 1.2 million kilometers from its star (roughly three times the distance between the Earth and the Moon), the planet is among the hottest ever detected; its estimated temperature is approximately 1650 degrees Celsius. "This star-hugging planet must be at least 1.6 times the mass of Jupiter, otherwise the star's gravitational muscle would pull the planet apart," said team leader Kailash Sahu of the Space Telescope Science Institute in Baltimore, Maryland. Such ultra-short period planets (USPPs) seem to occur only around dwarf stars.

The small star's relatively low temperature allows the planet to exist. "USPPs occur preferentially around normal red dwarf stars that are smaller and cooler than our Sun," Sahu said.^[1]

**SWEEPS-10**
Orbital elements
Extrasolar planet		List of extrasolar planets
Semimajor axis	(a)	0.008 AU
Orbital period	(P)	0.424 d
Inclination	(i)	>84°
Physical characteristics
Mass	(m)	1.6 M_J
Radius	(r)	1.24±0.23 R_J
Discovery information
Discovery date		October 4, 2006
Discoverer(s)		Jeremy McGovern
Detection method		Transit
Discovery status		Unconfirmed