The_Sun_Active - The Active Sun Phenomena Photosphere...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: The Active Sun Phenomena Photosphere Sunspots Chromosphere Prominences Corona Flares, Coronal Holes Sunspots Characteristics 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 Differential Rotation 25 days 0o latitude 28 days 40o latitude 36 days 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 Characteristics 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! Maunder Minimum From 1645 to 1715 there were No sunspots!!!! “Little Ice Age” Scan Card For Tests ...
View Full Document

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.

Ask a homework question - tutors are online