A beam tightly focused by a telescope could greatly outshine a planet's host
star at a particular wavelength, Townes realized, popping out as clearly as a red laser pointer aimed at someone from across a stadium flooded with white lights.
Planets with atmospheres are able to warp starlight in another way: while the body of the planet blocks a big chunk of starlight as it crosses in front of its host
star, the planet's thin, enveloping atmosphere absorbs starlight
at particular colors, or
wavelengths.