Download HERE

The Sun
1
Pictures taken from SOHO
Solar and Heliospheric Observatory
2
Facts about the Sun
• Composed of plasma (the 4th state of matter)
– Plasma- ionized gas electrically neutral atoms are split
into positively charged fragments and free electrons.
– Electrons are moving so fast they overcome the attraction
to the positive nucleus.
•
•
•
•
Age = 4.6 billion years old
10 billion years is its expected lifetime (HHe)
Diameter  1.5 million km OR 109 Earths wide
Mass  1.99 x 1030 kilograms or 300,000’s Earths
* volume of the Sun is 1,299,400 times bigger than the volume of
3
the Earth. You could fit OVER 1 million Earth’s in the Sun!
Sun Facts continued
• Rotation =
– 27 days at the equator
– 31 days near the poles
• Surface Temp = 5780 K or 10,4000F
• Core Temp = 16,000,000 K
• Most of its energy is released in the
visible wavelengths (yellow)
4
• The Sun is
AVERAGE.
– Average temp
– Average mass
– Even average color
(yellow is right in the
middle of ROYGBV)
• Large, HOT stars give
off most of their light
in the BLUE.
• Small, COOL stars
are red.
• BLUE is HOT, red is
not.
BIG, hot,
blue star
Sun
Most light given off
by the Sun is
Green/Yellow
Small, cool,
red star
5
Composition of the Sun
Composition
Hydrogen
Helium
Other
Surface
94%
5.9%
0.1%
Core
68%
32%
0.0
Total
74%
25%
very
small
6
Where does the energy come from?
•
•
•
•
Fusion- Hydrogren fusing into helium
mass lost is turned into energy.
E=mc2
Click HERE for fusion animation.
7
Why doesn’t the Sun blow itself up?
• Gravity is always trying
to pull matter together.
The mass of the Sun is
so great that it has a
hard time stopping
gravity.
• Hydrostatic equilibriumthe expansion of the
super hot ionized gas
(plasma) pushing out
EQUALS the
compression from
8
gravity pulling in.
Differential rotationthe equator of the Sun rotates faster than the poles. Causes
the magnetic field to become “warped” or tangled.
Causes massive magnetic field problems
9
Solar Max and Solar Min
• It takes 11 years for the Sun’s magnetic field to
become “warped” or “tangled” and right itself back
to normal.
• When the mag field lines are “normal” or not
tangled, we have Solar Minimum. Which means the
Sun is less active. Less flares, Sunspots, Aurora’s.
• When it’s “warped” or tangled, we have Solar
Maximum. More flares, sunspots, aurora’s.
• When the Sun “rights itself” or UNtangles the
magnetic field lines, the Magnetic NORTH and
10
SOUTH flip. South goes to the TOP, north= bottom
Warping the Sun’s magnetic field
11
Solar Max was in 2000/2001
Next 2012/2013
Last solar minimum 2008
Next 2019-ish
12
Sunspot Cycle
13
Surface Features of the Sun
•The Sun’s magnetic
field causes ALL...
-sunspots
-Flares
-prominences
14
•
•
•
•
•
•
•
Sunspots
cooler regions resulting in dark blemishes on the Sun’s
surface.
10,000 km across (about the diameter of E)
Have an umbra (dark center) and a penumbra (less shaded
surrounding)
Temps in the umbra reach 4500 K. (cooler than
surroundings). Appears dark, but it’s not.
Magnetic field is 1000 times greater than surrounding
surface.  This strong mag. field redirects convective hot
gas.
Usually associated with brighter areas called Plage- hotter
areas of rising convection (possibly)
22 year cycle in magnetic field polarity (N/S flipping)
15
Sunspots
ISS
Sunspot BIGGER
than the Earth
16
Sunspots are associated with…
• An increase in solar flares/prominence.
• An increase in the RELEASE of
radiation.
• There is a shift in the global average
temperatures as Sunspots change.
– More Sunspots, higher ave temps
17
What is the difference between a
solar flare and prominence?
• Basically they are the same thing.
• Flares an eruption on the Sun that shoots
out from the surface of the Sun for
thousands of kilometers.
• Prominence an eruption on the Sun shoots
out for thousands of kilometers and back
again forming LOOPS.
18
Solar Flare
19
Flare
20
Prominence
21
Filament
• When a flare or prominence shoots towards
Earth.
22
S
u
n
s
p
o
t
Plage
Filament
23
Problems
from
“Space
Weather”
The effects of solar storms on the ground can also be expensive. Surges
in power lines and long uninterrupted oil and gas lines can occur. The
extra current in the power lines can burn out transformers, leading to
large-scale brown-outs or blackouts.
Electricity in pipelines can enhance the rate of corrosion.
24
Problems
from
“Space
Weather”
Satellites are particularly vulnerable to electrical effects of Space
Weather as they are NOT buffeted by the incoming gas and radiation.
The charged particles and ionizing radiation causes our atmosphere to
expand, which in turn, creates extra drag on our satellites. This causes
a loss of altitude.
Too many charged particles can cause electrical components to burn
25
out.
At home, watch the following:
• Aurora’s
http://www.youtube.com/watch?v=7Mz2laHjVoQ&feature=related
• Sunspots
http://www.youtube.com/watch?v=uHdJ1lAHejw
• Warped Magnetic Field
http://www.youtube.com/watch?v=-PTQaOWkEfs
26
???
27
???
?
?
28
???
29