Astrodon Exo-Planet Filter - Clear with Blue-Blocking

Astrodon introduced the ExoPlanet-BB filter for use in amateur-scale telescopes to measure light curves of exoplanets.

Although it may not seem possible at first, astronomers with typical backyard equipment and sensitive CCD cameras have the capability to quantitatively measure small changes in light intensity as large exoplanets pass in front of their suns.
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