Jedidah Isler: How I fell in love with quasars, blazars and our incredible universe

71,522 views ・ 2015-04-21

TED


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My first love was for the night sky.
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Love is complicated.
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You're looking at a fly-through of the Hubble Space Telescope Ultra-Deep Field,
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one of the most distant images of our universe ever observed.
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Everything you see here is a galaxy,
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comprised of billions of stars each.
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And the farthest galaxy is a trillion, trillion kilometers away.
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As an astrophysicist, I have the awesome privilege of studying
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some of the most exotic objects in our universe.
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The objects that have captivated me from first crush throughout my career
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are supermassive, hyperactive black holes.
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Weighing one to 10 billion times the mass of our own sun,
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these galactic black holes are devouring material,
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at a rate of upwards of 1,000 times more
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than your "average" supermassive black hole.
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(Laughter)
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These two characteristics,
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with a few others, make them quasars.
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At the same time, the objects I study
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are producing some of the most powerful particle streams
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ever observed.
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These narrow streams, called jets,
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are moving at 99.99 percent of the speed of light,
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and are pointed directly at the Earth.
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These jetted, Earth-pointed, hyperactive and supermassive black holes
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are called blazars, or blazing quasars.
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What makes blazars so special is that they're some of the universe's
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most efficient particle accelerators,
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transporting incredible amounts of energy throughout a galaxy.
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Here, I'm showing an artist's conception of a blazar.
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The dinner plate by which material falls onto the black hole
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is called the accretion disc,
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shown here in blue.
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Some of that material is slingshotted around the black hole
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and accelerated to insanely high speeds
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in the jet, shown here in white.
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Although the blazar system is rare,
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the process by which nature pulls in material via a disk,
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and then flings some of it out via a jet, is more common.
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We'll eventually zoom out of the blazar system
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to show its approximate relationship to the larger galactic context.
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Beyond the cosmic accounting of what goes in to what goes out,
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one of the hot topics in blazar astrophysics right now
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is where the highest-energy jet emission comes from.
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In this image, I'm interested in where this white blob forms
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and if, as a result, there's any relationship between the jet
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and the accretion disc material.
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Clear answers to this question
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were almost completely inaccessible until 2008,
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when NASA launched a new telescope that better detects gamma ray light --
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that is, light with energies a million times higher
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than your standard x-ray scan.
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I simultaneously compare variations between the gamma ray light data
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and the visible light data from day to day and year to year,
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to better localize these gamma ray blobs.
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My research shows that in some instances,
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these blobs form much closer to the black hole
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than we initially thought.
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As we more confidently localize
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where these gamma ray blobs are forming,
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we can better understand how jets are being accelerated,
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and ultimately reveal the dynamic processes
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by which some of the most fascinating objects in our universe are formed.
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This all started as a love story.
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And it still is.
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This love transformed me from a curious, stargazing young girl
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to a professional astrophysicist,
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hot on the heels of celestial discovery.
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Who knew that chasing after the universe
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would ground me so deeply to my mission here on Earth.
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Then again, when do we ever know where love's first flutter
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will truly take us.
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Thank you.
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(Applause)
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