Transcript Slide 1 - NSTA Learning Center - National Science Teachers

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New NASA Views of Storms in Space
Presented by Dr. Eric Christian
January 19, 2011
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New NASA Views of Storms In Space
The Sun as a Star
Magnetism and the Sun
Solar Activity
Storms in Space (Space Weather)
Solar Science Now and in the Future
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The Sun as a Star
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Our Sun is a very ordinary star
Figure shows
relative sizes
and colors of
some nearby
stars.
Vega: 25 light years (ly)
U. Andromedae: 44 ly
Gamma Cephei: 45 ly
Sun: 93 million miles
Epsilon Eridani: 10.5 ly
Gliese 581: 20 ly
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Hertzsprung-Russell Diagram
Hotter
Brighter
Stars spend most
of their life on the
Main Sequence.
On the main
sequence, bigger
stars are brighter
and hotter.
There are fewer
big stars, many
more small stars.
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Poll Question:
Billions of years from now, the Sun will
end up as:
A:
B:
C:
D:
E:
A Supernova
A Black Hole
A Red Giant
A White Dwarf
A Neutron Star
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Why ordinary is good
Large, bright stars don’t last very long.
Smaller stars are more stable.
Largest stars only stay on the main sequence for a few million
years, the smallest can last a trillion.
Our Sun will be main sequence for about 10 billion years.
But smaller stars have a smaller “zone of habitability”, where
planets can have liquid water. Therefore a smaller chance of
worlds with life.
In the middle has long life and large zone of habitability.
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Life Cycles of Stars
The NASA websites
“Starchild” and “Imagine the
Universe” have posters and
activities on the Life Cycles
of Stars for elementary and
high school respectively.
http://imagine.gsfc.nasa.gov/
docs/teachers/lifecycles/stars
.html
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Any Questions?
The Sun as a Star
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Plasma, Magnetism
and The Sun
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Four Ordinary States of Matter
Solid: Keeps the same shape
Liquid: Fills up the bottom of the container, but
keeps the same volume
Gas: Fills up the container it’s in
Plasma: An electrically-charged gas
Most of the Universe is PLASMA!
Including the Sun and all stars
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Two types of Magnets
Permanent Magnet: Iron, Nickel, and a few other
elements that, when they solidify in a magnetic
field or are otherwise magnetized, remain
magnetized and generate their own magnetic field.
Electromagnet: Moving charged particles
generate a magnetic field. In a coil of wire, each
loop combines to make a stronger magnetic field.
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Think about Magnetic Objects in the
Solar System:
Is the Sun a permanent magnet or an
electromagnet?
How about the Earth?
How about Mars?
[Type your responses in the chat]
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The Sun is a magnetic star
The Sun is an electromagnet. Moving plasma
causes electric currents in the Sun, which
generate a magnetic field.
The Earth is also an electromagnet with the
magnetic field generated by currents at the molten
core-mantle boundary.
Mars has small, irregular magnetism (a permanent
magnet).
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You can see the magnetic field
of the Sun
Image from TRACE satellite of
magnetic loops on the Sun
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Any Questions?
Plasma, Magnetism
and The Sun
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Solar Activity
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Magnetism is the cause of solar variability
Differential rotation (the Sun’s equator spins faster
than the poles) “winds up” the solar magnetic field
Figures from TRACE website: trace.lmsal.com
I like to think of the Sun’s magnetic field as a ball
of rubber bands.
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11 year (approximately) solar cycle
The Sun’s magnetic field flips polarity every 11 years
This is the major factor in the Sun’s variability.
11 year of solar images in X-rays (left) and magnetic field (right)
When the field flips, there are more sunspots and more solar activity. This part of
the solar cycle is called Solar Maximum.
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11 year (approximately) solar cycle
The number of sunspots is the longest running direct observation of
solar activity.
11-year solar cycle is not constant in either duration or intensity.
Sunspots are an effect of solar activity and don’t exactly measure
solar activity.
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Chat: What is the Sun’s effect on
Global Warming
There has been a lot of political hype about Global
Warming, with some people claiming that all the recent
warmth is due to changes in the Sun, and others saying
that it’s all man-made.
What does the science say?
4/5/2016
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Sunspots
Very bright, just look dark
compared to rest of the Sun
From Hinode
Spacecraft
(Japanese/US
Mission)
Close up of Sunspot showing magnetic field strength (left) and visible light (right)
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Sunspots
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Prominences and filaments
Prominences are bright
loops off the edge of the
Sun.
Filaments are dark
ribbons on the face of the
Sun.
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Prominences and filaments . . .
Image from Solar Dynamics Observer
Are the same thing!
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Any Questions?
Solar Activity
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Storms in Space
(Space Weather)
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Coronal Mass Ejections (CMEs)
Big bubbles of plasma, particles and magnetic
field, that break away from the Sun.
The hurricanes of
space weather. CMEs
can have effects all the
way out to the edge of
the solar system.
Dangerous to
Astronauts, satellites,
and even to equipment
down on Earth
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Solar Flares
Magnetic Field suddenly snaps.
Particles are accelerated to almost the speed of light.
Dangerous to Astronauts and satellites.
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The Atmosphere of the Sun
The solar wind has blown a bubble in space that
extends all the way beyond Pluto!
4/5/2016
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Most recognized effect of Space Weather:
Auroras
Interaction of the Sun’s magnetic field and the Earth’s magnetic field.
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Aurora from Space
Skylab
Earth aurora
from space.
Other planets
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Space Weather is Important
4/5/2016
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Any Questions?
Storms in Space
(Space Weather)
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Solar Science Now …
And in the Future!
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STEREO (Solar Terrestrial Relations Observatory)
Our first 3D images of the Sun
STEREO Orbits
February 6th. The
360 degree Sun.
stereo.gsfc.nasa.gov
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Solar Dynamics Observatory (SDO)
The High-Definition Television of Solar Astronomy
Launched February,
2010
sdo.gsfc.nasa.gov
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NASA’s network of Space Weather Satellites
A fleet of
spacecraft spread
throughout the
solar system.
Includes both
weather stations
(local conditions)
and weather
satellites (image
large areas)
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Solar Probe Plus
Will be launched in 2018
Our first mission to
a star. Closest
approach is only
about 4 million
miles from the Sun.
The Earth is 93
million miles away
and the Sun is
400,000 miles in
radius.
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Sun Earth Day
sunearthday.nasa.gov
A yearly event for NASA Education and Public
Outreach. Every year there is a different topic, and
website includes lesson plans and activities,
podcasts, and much more. Join us this year for
“Ancient Mysteries, Future Discoveries”
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Sun Earth Day
Space Weather Viewer
http://sunearthday.gsfc.nasa.gov/spaceweather/
Pointers to lesson plans
http://sunearthday.nasa.gov/2011/getinvolved/
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Any Questions?
Solar Science Now …
And in the Future!
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Thank you to the sponsor of
tonight's Web Seminar:
http://learningcenter.nsta.org
http://www.elluminate.com
National Science Teachers Association
Dr. Francis Q. Eberle, Executive Director
Zipporah Miller, Associate Executive Director
Conferences and Programs
Al Byers, Assistant Executive Director e-Learning
NSTA Web Seminars
Paul Tingler, Director
Jeff Layman, Technical Coordinator
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