Andrew Yee
February 21st 06, 07:04 PM
University Relations
Iowa State University
Ames, Iowa
Contacts:
Lee Anne Willson, Physics and Astronomy
(515) 294-6765
Mike Krapfl, News Service
(515) 294-4917
2-20-06
The source of star dust
AMES, Iowa -- NASA's Stardust mission just traveled seven years and 2.88
billion miles to bring space dust back to earth laboratories.
Lee Anne Willson, a University Professor of physics and astronomy at Iowa
State University, has been working for 35 years to understand the stars
that produce some of that dust.
Willson calls her work "stellar gerontology" because she studies red
giants, the stars that expand and burn red and relatively cool as they
move through the final stages of their life cycles.
Willson presented some of her research findings at the Annual Meeting of
the American Association for the Advancement of Science in St. Louis on
Monday, Feb. 20. She also addressed and helped organize a press briefing
at the meeting titled, "Stardust: Solar System Birth and Death."
The press briefing also featured Don Brownlee, a professor of astronomy at
the University of Washington in Seattle and the lead scientist for the
National Aeronautics and Space Administration's Stardust mission. The
mission's capsule dropped to the Utah desert on Jan. 15 with what Brownlee
estimated to be more than a million comet and interstellar dust particles.
Scientists will study the dust to learn more about comets and the origins
of the solar system.
Willson said the origins of star dust are red giant stars characterized
by:
* Super size. Their stellar radius is about the size of earth's orbit.
* Changing brightness. Their brightness varies dramatically over the
course of a year-long cycle.
* High luminosity. They radiate several thousand times more power into
space than the sun.
Willson said the variability of those stars is fundamental to dust
formation. The variability produces shock waves which cause gasses to
expand and cool very rapidly. That creates the conditions that allow dust
formation closer to the star than would otherwise be possible. Recent
observations of translucent molecular shells around red giants provide
confirmation of Willson's theoretical analysis.
"These dust particles start their journeys in my stars and end up in the
solar system," Willson said.
And that's a big deal to all of us. Willson said some of that dust came
together some 4.6 billion years ago to create earth.
Iowa State University
Ames, Iowa
Contacts:
Lee Anne Willson, Physics and Astronomy
(515) 294-6765
Mike Krapfl, News Service
(515) 294-4917
2-20-06
The source of star dust
AMES, Iowa -- NASA's Stardust mission just traveled seven years and 2.88
billion miles to bring space dust back to earth laboratories.
Lee Anne Willson, a University Professor of physics and astronomy at Iowa
State University, has been working for 35 years to understand the stars
that produce some of that dust.
Willson calls her work "stellar gerontology" because she studies red
giants, the stars that expand and burn red and relatively cool as they
move through the final stages of their life cycles.
Willson presented some of her research findings at the Annual Meeting of
the American Association for the Advancement of Science in St. Louis on
Monday, Feb. 20. She also addressed and helped organize a press briefing
at the meeting titled, "Stardust: Solar System Birth and Death."
The press briefing also featured Don Brownlee, a professor of astronomy at
the University of Washington in Seattle and the lead scientist for the
National Aeronautics and Space Administration's Stardust mission. The
mission's capsule dropped to the Utah desert on Jan. 15 with what Brownlee
estimated to be more than a million comet and interstellar dust particles.
Scientists will study the dust to learn more about comets and the origins
of the solar system.
Willson said the origins of star dust are red giant stars characterized
by:
* Super size. Their stellar radius is about the size of earth's orbit.
* Changing brightness. Their brightness varies dramatically over the
course of a year-long cycle.
* High luminosity. They radiate several thousand times more power into
space than the sun.
Willson said the variability of those stars is fundamental to dust
formation. The variability produces shock waves which cause gasses to
expand and cool very rapidly. That creates the conditions that allow dust
formation closer to the star than would otherwise be possible. Recent
observations of translucent molecular shells around red giants provide
confirmation of Willson's theoretical analysis.
"These dust particles start their journeys in my stars and end up in the
solar system," Willson said.
And that's a big deal to all of us. Willson said some of that dust came
together some 4.6 billion years ago to create earth.