the active sun. sunspots umbra penumbra granulation
TRANSCRIPT
The Active Sun
Sunspots
Umbra Penumbra
Granulation
Features of Sunspots
Darker than surrounding photosphereCooler
Granulation inhibited (movie)Occur in pairsSunspot Cycle
Sunspot Cycle
0
40
80
120
160
200
1700 1750 1800 1850 1900 1950 2000
Year
Su
nsp
ot
Nu
mb
er
Maunder Butterfly Diagram
Magnetic Polarities
Opposite polarities within
a pair
Pairs in opposite hemispheres have opposite
polarity
Entire structure reverses
every cycle
S
N
S
N
S
N
Beginning of cycle Later in the same cycle
N
N
S
S
SN
N
S
The next cycle
N
N
S
S
Babcock Model
Two features combine to produce sunspotsGeneral Magnetic FieldDifferential Rotation
Wrapping Field Lines
Link
Model Check ListSpots first appear 30° from equator
opposite polarities within pairswitched polarities in other hemisphere
Become more numerous and closer to the equator as the wrapping continuesMaximum is reached midway
Magnetic field lines untanglefewer spots, closer to equatorwhen totally untangled, the field is flipped
Should Other Stars Have Spot Cycles?
RequirementsMagnetic FieldDifferential RotationInstability below photosphere
• Convective Zone
Plages
Prominences
Movie
Flares
October 29, 2003
Coronal Mass Ejection
Solar-Terrestrial Relationships
Light - HeatParticles - Solar Wind, Flares
Radio Communication DisruptionAurorae (The Movie)
Aurora Borealis
Earth’s Magnetic Field
Tree Rings
Width follows a 22-year cycleIn phase with sunspots
Maunder Minimum
Global Climate