New NASA Views of Storms in Space Presented by Dr. Eric Christian LIVE INTERACTIVE YOUR DESKTOP 1 January 19, 2011

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 2

The Sun as a Star 3

4 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

5 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.

6 Poll Question: Billions of years from now, the Sun will end up as: A: A Supernova B: A Black Hole C: A Red Giant D: A White Dwarf E: A Neutron Star

7 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.

8 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. docs/teachers/lifecycles/stars.html

The Sun as a Star 9 Any Questions?

Plasma, Magnetism and The Sun 10

11 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

12 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.

13 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]

14 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).

15 You can see the magnetic field of the Sun Image from TRACE satellite of magnetic loops on the Sun

Plasma, Magnetism and The Sun 16 Any Questions?

Solar Activity 17

18 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.

19 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.

20 11 year (approximately) solar cycle 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. The number of sunspots is the longest running direct observation of solar activity.

9/3/ 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?

22 Sunspots Very bright, just look dark compared to rest of the Sun Close up of Sunspot showing magnetic field strength (left) and visible light (right ) From Hinode Spacecraft (Japanese/US Mission)

23 Sunspots

24 Prominences and filaments Prominences are bright loops off the edge of the Sun. Filaments are dark ribbons on the face of the Sun.

25 Prominences and filaments... Are the same thing! Image from Solar Dynamics Observer

Solar Activity 26 Any Questions?

Storms in Space (Space Weather) 27

28 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

29 Solar Flares Magnetic Field suddenly snaps. Particles are accelerated to almost the speed of light. Dangerous to Astronauts and satellites.

9/3/ The Atmosphere of the Sun The solar wind has blown a bubble in space that extends all the way beyond Pluto!

31 Most recognized effect of Space Weather: Auroras Interaction of the Sun’s magnetic field and the Earth’s magnetic field.

32 Aurora from Space Skylab Other planets Earth aurora from space.

9/3/ Space Weather is Important

Storms in Space (Space Weather) 34 Any Questions?

Solar Science Now … And in the Future! 35

36 STEREO (Solar Terrestrial Relations Observatory) stereo.gsfc.nasa.gov February 6 th. The 360 degree Sun. STEREO Orbits Our first 3D images of the Sun

37 Solar Dynamics Observatory (SDO) The High-Definition Television of Solar Astronomy Launched February, 2010 sdo.gsfc.nasa.gov

38 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)

39 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.

40 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”

41 Sun Earth Day Space Weather Viewer Pointers to lesson plans

Solar Science Now … And in the Future! 42 Any Questions?

Thank you to the sponsor of tonight's Web Seminar:

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 LIVE INTERACTIVE YOUR DESKTOP NSTA Web Seminars Paul Tingler, Director Jeff Layman, Technical Coordinator