Currently, the most common ways to detect exoplanets are the photometric transit technique, which seeks dips in light due to planets passing in front of their host stars, and spectroscopic obÒ-Ò-servations, which detect radial velocity variations when a planet pulls on its star. Measuring radiÒ-Ò-al velocity shifts for Earth-sized planets with one-year orbits around Sun-like stars is not possible with current technology.
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