Stars
Ch. 29, page 830
Observe the Sun’s Rotation
1. Do not Look directly at the sun with your naked eye or
through the telescope.
2. Get a clean sheet of paper and a pencil
3. Place your paper under the image from the telescope.
Trace the outline of the Sun on your paper.
4. Trace the sunspots that appear as dark areas on the
Sun’s image Repeat this step several times over the
next week or two.
5. Measure the movement of the sunspots.
6. Calculate the Sun’s period of rotation.
7. Determine what is the estimated rate of motion of
the largest sunspot.
Dec. 4,
2013
http://sohowww.nascom.nasa.gov/sun
spots/
1.Calculate
the Sun’s
period of
rotation.
2.Determine
what is the
estimated
rate of
motion of
the largest
sunspot.
Ch. 29.1 The Sun, p. 830
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Photosphere
Chromosphere
Corona
Prominence
Solar Wind
Sunspot
Solar Flare
Fission
Fusion
Ch. 29.1 The Sun
• 109 Earths diameter
• 10 Jupiters diameter
Ch. 29.1 The Sun
• 330,000 x Earth Mass
• 1,048 x Jupiter’s Mass
• 99% of Solar System’s
mass
• 4 trillion trillion 150
watt light bulb/sec
• Interior density is 1.50
x 105 kg/m3 (a pair of
dice would weigh 1 kg)
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Ch. 29.1 The Sun
109 Earths diameter
10 Jupiters diameter
330,000 x Earth Mass
1,048 x Jupiter’s Mass
4 trillion trillion 150
watt light bulb/sec
• 99% of Solar System’s
mass
• Interior density is 1.50
x 105 kg/m3 (a pair of
dice would weigh 1 kg)
Ch. 29.1 The Sun
• 1 x 107 K interior
• Plasma
• No lead core
• 1.35 kilowatt/m2 on
earth’s surface vs 4
trillion trillion 150 watt
light bulbs / sec on the
sun
Ch. 29.1 The Sun
• Photosphere
• 400 km thick
• 5800 K
• Chromosphere
• 2500 km thick
• 30,000 K
Corona
Ch. 29.1 The Sun
• Corona
• Several million miles
from Chromosphere
• Strongest x-ray
emissions
• 1 million to 2 million K
Ch. 29.1 The Sun
• Solar Wind is charged particles and cause
Aurora Borealis
• Sunspots due to magnetic field pulling gases
together and cooling them
Ch. 29.1 The Sun
• Solar Flares: violent eruptions of particles
• Solar Prominences: an arc of gas ejected from
the chromosphere or gas that condenses on
the inner corona and falls back to sun
Ch. 29.1 The Sun
• Fission: breaking apart atoms that releases
particles and energy
Fission is almost the same as the word “Division”. Noah you’re AWESOME!
Ch. 29.1 The Sun
• Fission: breaking apart atoms that releases
particles and energy
Ch. 29.1 The Sun
• Fusion: two nuclei with low masses are
combined to form one nucleus of larger mass.
They usually repel each other due to the
identical charges, but at very hot temperatures
in the sun they are moving fast enough to
overcome this barrier
Ch. 29.1 The Sun
Bellringer: answer 3 and one more for Ex. Cr.
1. How many Jupiters or Earths can be lined up at
the diameter of the sun?
2. How is energy produced in the sun?
3. How hot is the interior of the sun in Kelvin?
4. Name one of the three outer layers of the sun?
5. Describe one of the following: sunspot, solar
flare, or solar wind.
Ch. 29.1 The Sun
Ch. 29.1 The Sun
• Light waves
• Gas particles absorb the energy of light and
they get energized by the light hitting them so
that they emit specific wavelengths of light
Ch. 29.1 The Sun
• Continuous Spectrum: A spectrum that has no
breaks in it, such as the one produced when
light is shown through an ordinary prism
Ch. 29.1 The Sun
• Emission Spectrum: A spectrum produced by a
non-compressed gas contains bright lines at
specific wavelengths. These are emission lines
of specific elements
Ch. 29.1 The Sun
• Absorption Spectrum: A spectrum produced
by the sun caused by different chemical
elements that absorb light at specific
wavelengths. The dark absorption lines are
the same as the emission lines for that
element.
Ch. 29.1 The Sun
Ch. 29.1 The Sun
Interior of the Sun website
How and where do the nuclear reactions take
place?
http://ircamera.as.arizona.edu/NatSci102/NatSc
i102/lectures/suninterior.htm
Ch. 29.2 Measuring the Stars
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Absolute magnitude
Apparent Magnitude
Binary star
Constellation
Parallax
Hertzsprung-Russell
Diagram (H-R)
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Doppler Shifts
Wavelength
Spectral Shift
Light Year
Parsec
Luminosity
Density
Main Sequence
(of stars)
Ch. 29.2 Measuring the Stars
• Luminosity: how much power the sun
gives off per second. Measured in watts.
• What is the Sun’s luminosity?
3.85 x 1024
One light year
We measure the luminosity of stars based on a
distance of 10 parsecs.
Parsec = a parsec (pc) is equal to 3.26 light years
(ly) or 3.086 x 1013 km
.26
Ch. 29.2 Measuring the Stars
• Absolute magnitude (a standard
measurement if the star was 10 pc away)
• Apparent Magnitude (what we see)
Hertzsprung-Russell
Diagram (H-R) Diagram
Page 844
Hertzsprung-Russell Diagram (H-R) Diagram
Most stars are currently classified under the
Morgan–Keenan (MKK) system using the
letters O, B, A, F, G, K, and M, a sequence
from hottest (O) to coolest (M). Useful
mnemonic for remembering the spectral
type letters is:“Oh, Boy, An F Grade Kills Me".
Page 844
Ch. 29.2 Measuring the Stars
Ch. 29.2 Measuring the Stars
Constellations: groups of the brightest stars
named after mythological characters,
animals, and everyday objects.
Watch the interactive night sky map here:
http://www.astroviewer.com/interactivenight-sky-map.php
The Big and Little Dippers and the
North Star
Big Dipper (Ursa Major)
Little Dipper (Ursa
Minor)
A binary star: two stars
that are
gravitationally bound
together and orbit a
common center
between their masses
http://en.wikipedia.org/wiki/File:Orbit5.gif
Constellations
Orion
Pleides
http://www.astroviewer.com/interactivenight-sky-map.php
Casseiopia
Ch. 29.2 Measuring the Stars
Three Easy Measurements of Stars
1. Doppler Effect (just like the shift of sound
as it “comes and goes”): as a star moves
back and forth against the background of
the universe shifts toward the blue when
moving toward us and toward the red
when moving away from us.
2. Parallax (Lab)
3. Spectral Lines (Lab)
Ch. 29.2 Measuring the Stars
Three Easy Measurements of Stars
1. Doppler Effect (just like the shift of sound
as it “comes and goes”)
2. Parallax (Lab) The apparent shift in
position of a star caused by the motion of
the observer. The closer the star the
greater the Parallax shift
3. Spectral Lines (Lab)
Ch. 29.2 Measuring the Stars
Three Easy Measurements of Stars
1. Doppler Effect (just like the shift of sound
as it “comes and goes”)
2. Parallax (Lab)
3. Spectral Lines (Lab) Emission lines on a
continuous spectrum or absorption
spectrum which indicate which elements
are present on a star.
Ch. 29.2 Measuring the Stars
Three Easy Measurements of Stars
1. Doppler Effect (just like the shift of sound as it “comes and goes”)
Ch. 29.2 Measuring the Stars
Three Easy Measurements of Stars
1. Parallax: the apparent shift in the position of a star caused
by the motion of the observer
Ch. 29.2 Measuring the Stars
Constellations
Watch the interactive night sky map here:
http://www.astroviewer.com/interactive-nightsky-map.php
Ch. 29.2 Measuring the Stars
Constellations:
Watch the interactive night
sky map here:
http://www.astroviewer.co
m/interactive-night-skymap.php
Ch. 29.2 Measuring the Stars
Constellations
Watch the interactive night
sky map here:
http://www.astroviewer.co
m/interactive-night-skymap.php
Ch. 29.2 Measuring the Stars
Constellations
Watch the interactive night
sky map here:
http://www.astroviewer.co
m/interactive-night-skymap.php
Ch. 29.2 Measuring the Stars
Binary stars are two stars that orbit around
each other. One of the seven stars in the
Big Dipper (Ursa Major) is actually a binary
star.
Star clusters are stars that orbit around each
other. Pleides is a great example.