In this lecture we'll talk about the possibilities
for future observations of extrasolar planetary
systems and what exciting things they will
be able to tell us.
The discovery of all these new planets around
distant stars is nothing short of amazing.
We've got some great detection techniques
right now, but there are ingenious new ideas
that should give us an even greater understanding
those fascinating worlds beyond our Sun.
Most of us wonder about whether there is life
elsewhere in the universe, and especially,
is there life like us?
Part of answering that question involves looking
for planets that could be Earth-like.
The Kepler mission has already found many
planet candidates that are Earth-size, but
this doesn't necessarily mean that they are
Earth-like with oceans and forests and an
atmosphere.
In the near-future we're likely to see the
Kepler and GAIA missions provide more data.
But to know the details about the newly discovered
planets, we'll need to do direct imaging and
spectroscopy.
The GAIA mission has the goal of making precise
measurements of the positions of more than
1 billion stars in the Milky Way Galaxy.
Scientists will be able to create a three-dimensional
map of the Milky Way Galaxy.
The astrometric measurements will also be
a means of looking for extrasolar planets.
GAIA will also be able to look for planets
like Kepler does, using the transit technique.
GAIA was launched December of 2013 and is
currently in its testing and calibration phases.
The indirect methods of planet detection have
served us well, but it would be really great
to observe the planets themselves.
As mentioned, this is a technically challenging
task.
Stars are big and bright, planets are dim
and small.
We're moving forward and applying technologies
like adaptive optics to assist us.
For example, this is an infrared image from
the Keck Telescope showing the direct detection
of a four planet system around the star HR
8799.
Light from the star in the center was mostly
blocked out during the exposure.
The planets here are much larger, brighter,
and farther from their star than the jovian
planets in our solar system are.
And this is a false-color composite image,
taken with the Hubble Space Telescope showing
the planet Fomalhaut b and a belt of icy,
rocky material.
Based on these observations, astronomers calculated
that the planet is in a 2,000-year-long, highly
elliptical orbit.
The black circle at the center of the image
is again blocking out the light from the bright
star, allowing reflected light from the belt
and planet to be photographed.
For me, it's hard not to get crazy excited
about this stuff.
This is a photo of an actual planet around
another star!
And our Milky Way galaxy is enormous.
We're only going to find more of these!
And maybe someday soon we'll find one with
evidence of life.
It's very exciting!
That's it for Chapter 13.
I hope you enjoyed learning about extrasolar
planets.
