posted on Apr, 25 2003 @ 11:58 PM
More than 100 exoplanets in orbit around stars other than the Sun have been found so far. But while their orbital periods and distances from their
central stars are well known, their true masses cannot be determined with certainty, only lower limits.
This fundamental limitation is inherent in the common observational method to discover exoplanets - the measurements of small and regular changes in
the central star''s velocity, caused by the planet''s gravitational pull as it orbits the star.
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