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

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

Jedidah Isler first fell in love with the night sky as a little girl. Now she’s an astrophysicist who studies supermassive hyperactive black holes. In a charming talk, she takes us trillions of kilometers from Earth to introduce us to objects that can be 1 to 10 billion times the mass of the sun — and which sometimes shoot powerful jet streams of particles in our direction.

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Video Language:
English
Team:
closed TED
Project:
TEDTalks
Duration:
04:19

English subtitles

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