6RODU (PLVVLRQ 95% of the Suns energy reaches us as sunshine, - PowerPoint PPT Presentation

6RODU (PLVVLRQ • 95% of the Sun’s energy reaches us as “sunshine,” that is, light and heat • Photosynthesis (how plants grow), sunburn, weather are all attributed to this energy • The last 5% of the energy determines space weather 4/10/00 1

7KH 6XQ • At 5 billion years old, our sun is an energy machine • The sun's energy released in 1 sec, could power the U.S. for 9 million years 4/10/00 2

3DUWV RI WKH 6XQ The sun is a gas ball with various temperatures and densities • Core: millions of degrees • Surface: thousands of degrees • Corona: millions of degrees 4/10/00 3

7KH 6XUIDFH :H 6HH Photosphere • “Surface” of the sun • You couldn’t stand on surface • Constantly bubbling • 6000 K 4/10/00 4

)DLQW 8SSHU $WPRVSKHUH Corona • Visible during an eclipse • This outer layer extends millions of miles • Earth is immersed in this 4/10/00 5

%HWZHHQ 6XQ DQG (DUWK • Called solar- terrestrial environment • Solar wind, blows 1 million miles/hr, • Shapes Earth’s magneto- sphere 4/10/00 6

(DUWK¶V 0DJQHWLF )LHOG • Earth's magnetic field, without solar wind distortion • Magnetic field lines channel charged particles 4/10/00 7

6XQ DQG (DUWK DUH $OLNH Each have: • Equator • Magnetic field, N and S poles • Rotation (“day”) • Seasons • Atmospheric Weather Active Quiet Summer Winter 4/10/00 8

6RODU $FWLYLW\ Active Quiet • Active and Quiet Sun look quite different • One Solar Cycle is 11 years long. 4/10/00 9

6XQVSRWV $ • Cooler regions 4400 Kelvin • Appear in moments or hours, last hours, days, or weeks • Disturbed magnetic field, is one cause for solar flares 4/10/00 10

6XQVSRWV 7UDYHO • Sunspots move across the surface of the sun as the sun rotates • They change as they age and may produce repeated flares 4/10/00 11

6RODU )ODUH • This sunspot, 2 Earths wide, produced a bright flare 4/10/00 12

3URPLQHQFH • Magnetic fields give structure to ejecta • When very disturbed, breaks and plasma goes shooting out into space. 4/10/00 13

2SWLFDO 7HOHVFRSHV • In white light one can easily see sunspots • Light is projected onto a sheet so the eye doesn't look directly through the telescope at the sun. • Telescope like one Galileo might have used 4/10/00 14

2WKHU 7HOHVFRSHV • Radio telescopes and satellite imager tell us other information about the Sun 4/10/00 15

(IIHFWV = $XURUD • The aurora is directly due to the energy coming from the sun • Aurora from space with the shuttle in foreground 4/10/00 16

(IIHFWV = 1DYLJDWLRQ • Ships at sea require good navigation signals • Navigation errors can lead to wasted fuel, groundings, and spilled cargo 4/10/00 17

(IIHFWV = 5DGLR • Signals can get lost or absorbed, bounce and miss the receivers • Communication over the poles at certain frequencies can be completely blacked out 4/10/00 18

(IIHFWV = (OHFWULF 3RZHU • Huge transformers can be damaged by geomagnetic storms • Blackouts can be widespread 4/10/00 19

(IIHFWV = 3LSHOLQHV Alaska Pipeline • Pipelines can corrode with geomagnetic storms • Without mitigation, corrosion can cause severe leaks and damage the environment 4/10/00 20

(IIHFWV = 6DWHOOLWHV • Satellites can be damaged, lost, returned to Earth early • Satellites sit in the space environment and alert us 4/10/00 21

(IIHFWV = 5DGLDWLRQ • Astronauts in space (EVA, Extra Vehicular Activity) • All Space Shuttle missions • SST (the Concorde) flying at high altitude, at high latitude 4/10/00 22

:RUN LQ 6SDFH • Dangers of space travel are many • Astronauts working on the Moon 4/10/00 23

(IIHFWV = &OLPDWH • Is the Sun's variability tied to Earth's climate? • Controversial correlation with droughts, ice ages, large-scale weather patterns on Earth 4/10/00 24

6XPPDU\ RI (IIHFWV Space Weather effects on: • Satellites * What technology is dependent on satellties? • Navigation * What are the risks of lost navigation signals? • Manned Space Flights * As an astronaut, would you care about this? • Communication * How are communications disrupted? • Electric Power * How would you know about this disruption? 4/10/00 25

12$$ 6SDFH :HDWKHU 6FDOHV Category Effects • Easy way to communicate Geomagnetic Satellites, Power Storms Grids, other conditions and G1-G5 forecasts • Like the hurricane Solar Radiation Biological, or earthquake Storms Satellites, other S1-S5 scales • Will be hearing Radio Navigation, these, seeing them Blackouts Radio R1-R5 in the news 4/10/00 26

12$$ 6FLHQFH (G 3RVWHU • Poster shows effects on different systems • Also Facts about space weather Questions to answer Websites What would you like to study about Space Weather? 4/10/00 27