Washington: The first four exoplanets of 2012 have been spotted orbiting four distant stars merely four days into the New Year.
All four alien worlds, known as “hot Jupiters”, are large gas giant planets orbiting very close to their stars. Their orbits are aligned just right with the Earth so that when they pass in front of their parent stars, they slightly dim the starlight from view, Discovery News reported.
As exoplanets pass in front of their stars, a small dip in star brightness may be detected. This detection method is known as the “transit method”. This is in addition to the “radial velocity method”, when the gravitational pull of an exoplanet causes its parent star to wobble slightly.
However, this most recent discovery comes from a ground-based telescope system maintained by the Harvard-Smithsonian Center for Astrophysics.
The Hungarian-made Automated Telescope Network (HATNet) Project consists of six small (11-cm diameter), wide-field automated telescopes based at the Fred Lawrence Whipple Observatory in Arizona and The Submillimeter Array atop Mauna Kea, Hawaii.
HAT-P-34b, HAT-P-35b, HAT-P-36b and HAT-P-37b have very tight orbits around their stars, completing a “year” in only 5.5-, 3.6-, 1.3- and 2.8-days respectively.
Apart from having breakneck orbital speeds, one of the HAT-P-34b is notable for having a very elongated or “eccentric” orbit. Only four other transiting exoplanets are known to have more eccentric orbits.
Although many “hot Jupiter” exoplanets are known to exist, this marks the start of a very exciting year of extrasolar planet hunting.