Download Stars Take Center Stage in

H i g h l i g h t s
S c i e n c e
T e r a G r i d
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TeraGrid
resources are
called on to create
vertigo-inducing
planetarium
“Journey”
Stars Take Center Stage in
New York City
This visualization shows the
generation of magnetic field
in the solar convection zone
and its connection to a
sunspot at the visible surface
of the sun. Note that the
sunspot (with a size slightly
larger than earth) is
enlarged for better visibility
and not in proper scale relative to the sun.
Image courtesy of American
Museum of Natural History
Narrated by Whoopi Goldberg, the 25-minute show takes
viewers on an intergalactic tour of pulsing star nurseries,
dying red giants, and even the churning interior of our own
sun.
"Journey to the Stars" projects cutting-edge images and
computer visualizations onto the 87-foot, seven-millionpixel dome of the museum's planetarium. The space show
explains how dark matter's gravity gathered the primordial
gas in the universe to form the first stars, and how these massive stars exploded, seeding the galaxy with new stars and
the chemical elements that made life possible.
The centerpiece, and the most difficult sequence to depict
scientifically, is a flight into the center of the sun. There,
convective plasma roils, nuclear explosions rock the sun's
core, and undulating magnetic waves spiral from the sun
to the distant reaches of space. These sequences are
based on the research of Juri Toomre, professor of astrophysics at The University of Colorado at Boulder, and
Matthias Rempel, a researcher at the National Center for
Atmospheric Research (NCAR).
Toomre has been studying solar dynamism for more than
a decade. A self-proclaimed “deep miner” of the sun, his
focus has been the sun's internal, unseen structures rather
than its outer regions. “It's not enough to know what comes
out of the surface,” Toomre says. “We would like to understand how the magnetic engine of a star works, how it
churns away and how it builds orderly fields. This is one of
the top ten questions in physics.”
Toomre sets his sights beyond
the reach of any telescope to
parts of the sun that can only
be observed indirectly. And
computer simulations are the
most useful tools for his invesJuri Toomre and Benjamin Brown,
University of Colorado
tigations. “Simulations are
our eyes for thinking,” he says. “They provide insights and
give us hints about the dynamics in the sun.”
Working with doctoral researcher Ben Brown, Toomre's
research on the Ranger supercomputer, based at the
Texas Advanced Computing Center (TACC), led to the unexpected discovery of “Christmas-like wreaths” of magnetism occupying a large portion of the inside of the sun.
Because they're within the middle 50 percent of the sun—
the convection zone—you can't see these phenomena
directly. However, you can detect them in the eruption of
magnetic fields to the surface, according to Toomre.
The visuals of the sun were produced from solar data and
numerical simulations using supercomputing resources
and specialized visualization software. Brown used the
Visualization and Analysis Platform for Ocean,
Atmosphere, and Solar Researchers (VAPOR), a tool developed by NCAR in collaboration with the University of
California, Davis and the Ohio State University. The
sequences include simulated “flybys” through the
interior of the sun, revealing the dynamos and convection
that churn at and beneath the surface. “It may force us to
reconsider some of our ideas about how the solar interior
operates,” Toomre says.
NSF grants: 03-25934, 09-06379.6.
More Information:
http://www.ucar.edu/news/releases/2009/teragrid.jsp
Sunspots Spotlighted
in Star “Journey”
Matthias Rempel , a researcher at the National
Center for Atmospheric Research, provided visualizations of sunspots for the “Journey to the Stars,”
after developing some of the most comprehensive
numerical models of sunspots ever created.
Sunspots encompass intense magnetic activity that
is associated with solar flares and massive ejections
of plasma that can buffet Earth's atmosphere. The
resulting damage to power grids, satellites, and
other sensitive technological systems takes an economic toll on a rising number of industries.
"If you do astrophysics, it's a little detached from
what people do in their normal lives, so it's always a
challenge to explain what you're doing and why,”
says Rempel. “Having an opportunity to show really
interesting science through a planetarium show like
this helps to give this message back to the public."
The Hayden space show capitalizes on these images.
“We knew that we wanted to treat the sun in a terrific and powerful way to reveal not just the surface but
to take our audience into the sun, through the convective layer to the core,” says Ro Kinzler, the film's
producer. “The results are beautiful. No one has
seen the sun in this way and the resources from
TACC and NCAR made it possible.”
Snapshot of convection patterns
in a solar simulation with
broad upflows in light
tones and fast narrow
downflows in dark tones.
The polar regions near the
top of the image have
cyclonic swirling convection while the equatorial
regions have broader patterns.
Stars Take Center Stage in New York City T e r a G r i d 2 0 0 9
E
ver since humans first looked toward the heavens, those glittering bits known as stars have
shaken and stirred their inner feelings and conscious thoughts. This summer, stars took center
stage in a vertigo-producing video at the American Museum
of Natural History's Hayden Planetarium in New York City,
thanks to resources and expertise from the TeraGrid.
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