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Unformatted text preview: The Active Sun Phenomena
Photosphere Sunspots Chromosphere Prominences Corona Flares, Coronal Holes Sunspots
1500 K cooler than the surface
Last for a couple of months
Frequently in groups of 2-20 members
Sizes are usually larger than the Earth Sunspot Movie Rotation of the Sun
Sunspots were used by Galileo to
determine the Sun’s rotation
80o latitude Solar Rotation Movie PRS Question
1. A single sunspot “lives” for about
a. 11 years
c. 2 months
b. 22 years
d. 2 weeks e. 2 days Solar Cycle New Cycle Started
NASA is predicting that, with the new cycle of solar activity, satellites will be
disrupted, which will have an affect on GPS navigation and other systems.
“On January 4, 2008, a reversed-polarity sunspot appeared—and this signals
the start of Solar Cycle 24,” says David Hathaway of the Marshall Space
Flight Center. Solar activity waxes and wanes in 11-year cycles. Lately, we’ve
been experiencing the low ebb, “very few flares, sunspots, or activity of any
kind,” says Hathaway. “Solar minimum is upon us.”
The previous solar cycle, Solar Cycle 23, peaked in 2000-2002 with many
furious solar storms. That cycle decayed as usual to the present quiet leaving
solar physicists little to do other than wonder, when would the next cycle
begin? Sunspot Maximum . Solar Latitude Effect Magnetogram Magnetic Fields Magnetic Influence Solar Magnetic Dynamo Theory PRS Question
2. During the course of a sunspot cycle, the regions of sunspot occurrence move
a. from the northern to the southern hemisphere across the equator
b. poleward, moving from 10o to 30o latitude
c. equatorward, moving from the poles to the equator
d. equatorward, moving from 30o to 10o
e. not at all H Images of the Chromosphere Filaments Prominences Prominences
Eruptive and quiescent varieties
Curving loops are anchored by
differing magnetic poles
Associated with sunspots
Some last for a few hours, others
for a few months Show DVDs
Prominences 22, 28 Coronal Activity Coronal Holes
Best seen in X-rays Flares
Millions of H Bombs X-ray Movie Show DVDs
Solar Wind & Magnetosphere 23, 25, 26 Solar Cycle Activity 27 Coronal Mass Ejections Solar-Terrestrial Interactions
Stream of charged particles, mainly
protons. The solar wind exists
because the gases in the corona are
too hot to be confined by solar
gravity. The speed of the solar wind
near the Earth’s orbit averages about
400 km/s, and its density is usually
two to ten ions per cubic centimeter.
But both are highly variable. The
solar wind’s interaction with the
Earth’s atmosphere creates aurora. Exceptions!
From 1645 to 1715 there were No sunspots!!!!
“Little Ice Age” Scan Card For Tests ...
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This note was uploaded on 03/04/2012 for the course PHYS 2022 taught by Professor Jarrio during the Spring '12 term at Central GA Tech.
- Spring '12