4000 Exoplanets
Over 4000 planets are now known to exist outside our Solar System.
Known as
exoplanets, this milestone was passed last month, as recorded by
NASA's Exoplanet Archive.
The featured video
highlights these exoplanets in sound and light,
starting chronologically from the first confirmed detection in 1992 and continuing into 2019.
The entire night sky is first
shown compressed with the
central band of our
Milky Way Galaxy making a giant U.
Exoplanets detected
by slight jiggles in their parents-star's colors (radial velocity) appear in pink,
while those detected by slight dips in their parent star's brightness
(transit) are shown in purple.
Further, those exoplanets
imaged directly appear in orange,
while those detected by
gravitationally magnifying
the light of a background star
(microlensing) are shown in green.
The faster a planet orbits its parent star,
the higher the accompanying
tone played.
The retired
Kepler satellite has discovered
about half of these first 4000 exoplanets
in just one region of the sky, while the
TESS mission
is on track to find even more, all over the sky, orbiting the
brightest nearby stars.
Finding
exoplanets
not only helps humanity to better understand the potential
prevalence of life elsewhere in the universe, but also how our
Earth and
Solar System were formed.