outer layers of the sun’s atmosphere
DESCRIPTION
Outer Layers of the Sun’s Atmosphere. Photosphere - the 5800 K layer we see Chromosphere - the red layer observed using a hydrogen filter at a million degrees Corona - the incredibly thin outer atmosphere at millions of degrees. The photosphere is the visible layer of the Sun. - PowerPoint PPT PresentationTRANSCRIPT
Outer Layers of the Sun’s Atmosphere
• Photosphere - the 5800 K layer we see
• Chromosphere - the red layer observed using a hydrogen filter at a million degrees
• Corona - the incredibly thin outer atmosphere at millions of degrees
The photosphere is the visible layer of the
SunGranulation caused by convection
Thermal Convection
movie
Granulation caused by convection
Sunspots are the most well
known feature on
the photosphere
Above the photosphere, the chromosphere is characterized by
spikes of gas called spicules
Supergranules surrounded by spicules
The corona ejects some of its mass into space as the solar wind
Solar Wind• Charged particles (mostly protons
and electrons) streaming outward from the sun at 450 km/sec
• Causes • comet’s tails• aurorae
Monitoring sunspots reveals the solar cycle and the Sun’s rotation
The daily movement of sunspots reveals that
the Sun’s rotation
takes about 4 weeks
The annual change in numbers of sunspots reveals that the Sun experiences an 11-year solar cycle
Maximum number
Minimum number
The cyclical change in the latitude of sunspots also reveals that the Sun experiences an 11-year solar cycle
The Sun’s magnetic fields create sunspots
Zeeman effect - spectral lines split in regions of high magnetic fields
Magnetic field lines connect sunspots on the Sun’s photosphere
Babcock’s magnetic dynamo is one possible explanation of the sunspot cycle where magnetic field lines become complexly entangled after many solar rotations
Solar magnetic fields also create other atmospheric phenomena
• plages• filaments
Solar magnetic fields also create other atmospheric phenomena
• plages• filaments• prominences
Solar magnetic fields also create other atmospheric phenomena
• plages• filaments• prominences• solar flares
Solar magnetic fields also create other atmospheric phenomena
• plages• filaments• prominences• solar flares• coronal holes
Solar magnetic fields also create other atmospheric phenomena
• plages• filaments• prominences• solar flares
• coronal holes• coronal mass
ejections (CMEs)
Thermonuclear reactions in the core of the Sun
produce its energy
At extremely high temperatures and pressures, 4 Hydrogen atoms can combine to make 1 Helium atom and release
energy in the process according to E = mc2
4H He + energy
HYDROGEN FUSION
Solar models
describe how
energy escapes from the
Sun’s core through
the:
• Core• Radiative zone• Convective Zone
Helioseismology is the study of solar vibrations in order to
determine the detailed interior structure of the Sun
Quiz 3
Review
1. The Doppler effect is the change in the wavelength of light caused by the source
A) being within a high gravitational field.
B) being embedded in a cloud of dust and gas.
C) being in an intense magnetic field.
D) moving with respect to the observer.
Quiz 3
Answer: D
Quiz 3
Answer:
2. 98% of the mass of the universe is in the form of
A) hydrogen and helium.
B) nitrogen and oxygen.
C) iron and silicon.
D) hydrogen.
A
Quiz 3
Answer:
3. The correct sequence of planets in our solar system, from the Sun outward, is
A) Mercury, Earth, Venus, Mars, Jupiter, Saturn, Uranus, Neptune.
B) Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.
C) Mercury, Venus, Earth, Mars, Saturn, Uranus, Jupiter, Neptune.
D) Mercury, Venus, Mars, Earth, Jupiter, Saturn, Uranus, Neptune.
B
Quiz 3
Answer:
4. The San Andreas fault in California is an example of
A) a subduction zone, a region where two tectonic plates are pushing directly against oneanother.
B) a hot spot, where warm material rises due to convection in the Earth's mantle.
C) a spreading center, where two tectonic plates are being pushed away from each other.
D) a transform fault, where two tectonic plates are sliding past each other.
D
Quiz 3
Answer:
5. Most of the craters on the Moon were formed by
A) water erosion, followed by evaporation early in the Moon's history, leaving behind theempty basins, the maria, and craters.
B) a nuclear war in which the lunar inhabitants wiped themselves off the face of the Moon.
C) bombardment by objects of various sizes from space.
D) volcanic action, the craters being the old calderas of volcanoes.
C
Quiz 3
Answer:
6. What is the major constituent of the atmosphere of both Venus and Mars?
A) CO2 (carbon dioxide).
B) CH4 (methane or natural gas).
C) H2O (water vapor).
D) H2 (hydrogen).
A
Quiz 3
Answer:
7. Which of the following objects rotates the most quickly around its own axis?
A) Venus.
B) The Earth's Moon.
C) Earth.
D) Jupiter.
D
Quiz 3
Answer:
8. How did Comet Shoemaker-Levy 9 achieve lasting fame?
A) It became the first comet to be visited by spacecraft.
B) It crashed into Jupiter.
C) It exploded after passing too close to the Sun.
D) It just missed the Earth, passing between the Moon and the Earth.
B
Quiz 3
Answer:
9. Which satellite of Jupiter is volcanically active?
A) Europa
B) Io
C) Callisto
D) Ganymede
B
Quiz 3
Answer:
10. What is the composition of Saturn's rings?
A) Particles of methane and ammonia ice.
B) Sodium and sulfur ions.
C) Small grains of rock.
D) Water ice or ice-coated rock.
D