Details of the observation The new method for observing distant planets, used by both groups, involves measuring light emissions from a star while a suspected planet passes in front of the star during its normal orbit. Researchers first estimate the diameter of the host star, then by measuring the dip in starlight and the duration of the transit, they can estimate the planet's size. For Charbonneau and Brown, the more complete observations allowed for what Charbonneau says is a more accurate estimate of the planet's size. The planet orbits the star every 3.5 days. Henry had figured the planet to be slightly larger than what Charbonneau's calculations show.
Researchers say it is about the same age, color and size as our sun.
Earlier this month, British astronomers used yet another method to glean important clues about a different extrasolar planet. Though the method is unconfirmed, the team appears to have discerned starlight reflecting off the planet, providing even better direct measurements of an extrasolar planet's size and mass. The method, still unconfirmed, would be a first step toward understanding the composition of exoplanets. After one giant planet forms around a star, others could develop in a relative eyeblink, a new computer model shows. Five of the planets may hold water, researchers say.