Anjali Tripathi: Why Earth may someday look like Mars
安佳丽 特里帕西: 为何地球终有一日将变成火星
Anjali Tripathi explores planets to uncover the processes that make and destroy them. Full bio
Double-click the English transcript below to play the video.
at the stars at night,
is what you can't see,
or almost every star,
we tend to think of faraway things
that are amazing about Earth
to find things that are like that.
we're finding amazing things.
about an amazing thing here on Earth.
and never coming back.
as the Earth's atmosphere.
that form a thin blue line
the International Space Station,
from too many impacts,
at least a little bit.
is not specific to planet Earth.
to be a planet, if you ask me,
but throughout the universe,
about planets themselves.
about the solar system,
there are eight planets, maybe nine.
who are stressed by this picture,
we're including Pluto.
and atmospheric escape,
around other stars that we can't see
just stuck together
and have so much gravity.
is really at play here.
characteristic about planets
in the solar system are orbiting around.
atmospheric escape.
drive atmospheric escape from planets
particles and light and heat
of lanterns in Thailand at a festival,
can propel gasses upward.
and only bound by gravity,
causing atmospheric escape
between heating from the star
of gravity on the planet.
a minute for hydrogen
of escaping hydrogen looks like,
like oxygen and nitrogen
that conclusively show us
tightly bound to us here on Earth
reaching out far into space,
in undergoing atmospheric escape.
is much smaller than Earth,
with which to hold on to its atmosphere.
than the Earth's.
that it didn't have an atmosphere
Mars used to have a wetter past,
it broke up into hydrogen and oxygen,
it escaped into space,
rusty red color that we see.
probably happened,
at Mars called the MAVEN satellite,
is to study atmospheric escape.
and Volatile Evolution spacecraft.
shown pictures very similar
was losing its atmosphere,
you can see in the red circle
escaping away from the planet.
the size of the planet,
no longer bound to that planet.
from that lost hydrogen.
the only gas that's lost.
and some oxygen and nitrogen,
at the oxygen being lost from Mars.
that because oxygen is heavier,
away from the planet.
into that red circle.
atmospheric escape on our own planet
and send spacecraft
about the past of planets
can learn about the future
that we can't see.
before I go on to that,
photos like this of Pluto,
is currently studying atmospheric escape
that I did want to talk about
that's not our Sun
or extrasolar planet.
at that star in the middle,
that are going past it all the time,
the light from the star
in the night sky
to detect over 5,000 planets
many more out there, like I mentioned.
from these stars,
is not the planet itself,
a dimming of the light
decreases in front of the star,
that you saw before.
in different wavelengths.
and Mars in ultraviolet light.
with the Hubble Space Telescope,
much less light from the star,
an extended atmosphere of hydrogen
more of the light that you see.
we've actually been able to discover
that are undergoing atmospheric escape.
can be called hot Jupiters,
they're gas planets like Jupiter,
lightweight gas that's ready to escape,
of atmospheric escape.
of hydrogen being lost on Earth,
pounds of hydrogen every minute.
does this make the planet cease to exist?
that people wondered
closer to the Sun are rocky,
are bigger and more gaseous.
with something like Jupiter
with something like a hot Jupiter,
with Mercury or the Earth.
would have gotten away
significantly impacted it
than what you started with.
with us here on Earth?
is going to become very intense.
gas streaming off from a hot Jupiter,
that is broken down,
into space more rapidly,
with this dry, reddish planet.
for a few billion years,
to be aware of what's going on,
is happening as we speak.
that you hear about happening in space
to learn about these worlds.
or exoplanets like hot Jupiters,
about our planet here on Earth.
you think that space is far away.
ABOUT THE SPEAKER
Anjali Tripathi - AstrophysicistAnjali Tripathi explores planets to uncover the processes that make and destroy them.
Why you should listen
Even though Anjali Tripathi worked on NASA's Mars rovers in high school, the California native never expected to become an astronomer. Unlike the earthquakes she researched early on, astronomy seemed unconnected from daily life. As she has since discovered, exploring distant planets has a lot to do with life itself -- including the fate of the air we breathe. Using some of the most powerful telescopes and supercomputers, Tripathi studies how seemingly permanent planets change over time. She has pioneered the characterization of planet-forming environments and developed computer simulations to trace the 3D structure of planet atmospheres that are shrinking due to evaporation.
A natural teacher, Tripathi makes complex science concepts relevant and easy to understand. She believes that everyone can understand science -- even rocket science. She has partnered with the Smithsonian, Teach for America and others to increase scientific literacy and spread enthusiasm for the subject. Her engaging and humorous talks feature real world connections and unusual props, including a fully functioning Mars Pathfinder rover or full-size solar car.
Tripathi earned degrees in physics and astronomy from M.I.T., the University of Cambridge and Harvard University. Recognized as a promising American leader with a commitment to public service, Tripathi is a 2016-17 White House Fellow.
Anjali Tripathi | Speaker | TED.com