Strange new worlds:
Planet Hunters
“... the ways by which men arrive at knowledge of
the celestial things are hardly less wonderful than the
nature of these things themselves” – Johannes Kepler
in the space sciences is that of exoplanetology.
This is the search for worlds other than the eight in
astrophysics, astronomy, planetology, geochemistry,
astrochemistry and astrogeology in the effort to
and detection methods have been developed and
lists the multiple detection methods (top left) and
shows how the transit method has greatly increased
the number of detections - far right bar. The “transit
method” has recently contributed greatly to the rate
of exoplanet discoveries as seen during the “Kepler
have multiple planets. The Kepler Space Telescope
discoveries to date.
Most excitingly there are 21,267,575 Transit Survey
Light Curves. These are the results of exoplanet
searches by astronomers via photometric transits o f
potential planets around host stars. The number of
detections by this “transit method” has exploded in the
Image #9: Exoplanet detection methods.
Credit: NASA’s Exoplanet Archive
supposition further, the search for extra-terrestrial
Intelligence seeks out intelligence.
The Kepler Space Telescope was launched in March
2009 to look for exoplanets by using the transit method.
Kepler stares at the Cygnus constellation in its Field of
View every thirty minutes looking for such transiting
planets that slightly dim their parent star’s starlight, as
viewed by the space telescope. Smaller planets similar
to Earth’s size will dim their parent star’s brightness only
slightly. Larger planets also known as “Super Jupiters”
will also dim their parent’s star’s brightness but not as
much as a smaller Earth size planet would.
These time series “snapshots” of changing brightness
in these stars are called “light curves” and data for
over 150,000 stars is sent to Earth regularly. The light
available from the Kepler mission.
Clearly, the huge amounts of precise data coming
from Kepler have awed astronomers and needs to
be analysed. Rooms full of super computers could
programming, can also miss the non-standard signs of
an exoplanet or its cosmic footprints.
Building on the success of Galaxy Zoo, the talent for
a large global resource of human pattern recognition
was recognised once more. A new Zooniverse project,
Image #8: The blue bars show those exoplanets known by size before the
Kepler Planet Bonanza announcement earlier this year. The gold bars show
has vastly outstripped the combined discovery rates
of the last 25 years. The inferred conclusion means that
there are billions of worlds in our own galaxy, many
of which could be capable of supporting life, and
just perhaps many where life may have developed
just as it has done on Earth. Astronomers dating back
to antiquity have long held this view. Extending this
www.RocketSTEM .org
Yale University.
A simulation of a light curve is shown in image #10.
This uses a star about the same size as our Sun and
different sizes of planets that pass in front of that star.
The distributions of white dots represent uninterrupted
starlight, as if no planets were transiting in front of
that star. However, what would happen if a planet
the size of Jupiter would pass in front of that star? The
light would noticeably dip for the period that planet
was in front of that star, as seen by the dip of the
blue dots over a day and a half of observation. This
is shown to scale as a Jupiter size planet 11.2 times
Earth’s diameter and a tenth the diameter of the Sun.
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