Transcript The Dynamic Earth and Space Geodesy, SC/EATS 1010

The Dynamic Earth and Space Geodesy
EATS 1010 3.0 [Fall 2011]
Instructor: Gary Jarvis, Department of Earth and Space
Science & Engineering (ESSE)
117 Petrie Science & Engineering Building
[email protected], 416-736-2100 Ext. 77710
Laboratory Coordinator: Terry Du, 77706 [email protected]
Text:
The Dynamic Earth and Space Geodesy, SC/EATS 1010 3.0
(Custom Publication for York University)
ESSE office: 102 Petrie Science & Engineering,
416-736-2100 Ext. 55245
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The Dynamic Earth and Space Geodesy
EATS 1010 3.0 [Fall 2011]
Earth as a Planetary Body in Space
Topics
•Origin of the Earth
•Impact Craters
•Earth’s Interior
•Plate Tectonics
•Geomagnetism
•Seismology
•Space Geodesy & Geomatics
•VLBI
•GPS
•GIS
•Remote Sensing
Large Scale
Small Scale
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The Dynamic Earth and Space Geodesy
EATS 1010 3.0 [Fall 2011]
Course Marking Scheme & Schedule
5 Laboratory Exercises: 20%
Sept. 19 – Nov. 25
Mid-Term Test:
30%
October 25
Final Exam:
50%
December 8 – 22.
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EATS 1010 3.0 Lab. Timetable
(Fall 2011)
Group
Day
Time
Lab 1
Lab 2
Lab 3
Lab 4
Lab 5
Planet
Minerals Plate
GPS
Seismology
Earth
Tectonics
_______________________________________________________________________
1
2
M
M
11:30
2:30
Sept. 19 Oct. 3
Sept. 19 Oct. 3
Oct. 24
Oct. 24
Nov. 7
Nov. 7
Nov. 21
Nov. 21
3
4
T
T
11:30
2:30
Sept. 20 Oct. 4
Sept. 20 Oct. 4
Oct. 25
Oct. 25
Nov. 8
Nov. 8
Nov. 22
Nov. 22
5
6
W
W
11:30
2:30
Sept. 21 Oct. 5
Sept. 21 Oct. 5
Oct. 26
Oct. 26
Nov. 9
Nov. 9
Nov. 23
Nov. 23
7
8
R
R
11:30
2:30
Sept. 22 Oct. 6
Sept. 22 Oct. 6
Oct. 27
Oct. 27
Nov. 10
Nov. 10
Nov. 24
Nov. 24
9
10
F
F
8:30
11:30
Sept.23 Oct. 7
Sept. 23 Oct. 7
Oct. 28
Oct. 28
Nov. 11
Nov. 11
Nov. 25
Nov. 25
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Attendance
Lectures
- Notes are essential.
Text only covers about 50% of material
Laboratory Sessions
- Mandatory – zero tolerance
- Change of lab group only with permission of lab.
coordinator.
- Lab exercises must be submitted to your group TA.
Otherwise no mark.
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The Visible Universe
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galaxy
galaxy cluster
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quasar
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galaxy
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quasar
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galaxy cluster
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quasar
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Film: Powers of 10
Galaxies
Astronomers can see billions of galaxies.
Photograph from the Hubble
space telescope.
The Sun
There are 100 billion "Suns" in a galaxy like our own Milky Way
Galaxy.
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The Milky Way Galaxy as seen edge on
from the Solar System
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The Milky Way
On a clear dark night
With telescope and time exposure
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Our Solar System
Our solar system consists of an average-size star we call the
Sun; the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn,
Uranus and Neptune; and the dwarf planet Pluto.
It also includes: the satellites of the planets; numerous comets,
asteroids, and meteoroids; and the interplanetary medium.
Sun
Jupiter
Saturn
Uranus
Neptune
Pluto
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Relative sizes of planets
Formation of the Solar System
The “Nebular Hypothesis”
A cloud of interstellar gas/dust, the "solar nebula", including
material formed in previous generations of stars, is
disturbed (for example, by the shock wave from a nearby
supernova).
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Formation of the Solar System
1. Contraction: The cloud starts collapsing under its own
gravity.
The collapsing, spinning nebula begins to flatten into a
rotating pancake.
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Formation of the Solar System
2. A Protostar forms in the centre,
when the core becomes dense
enough; later will become the Sun.
3. Dust grains stick to each other
and sweep their paths, forming
larger particles (Planetesimals).
4. Orbital paths are cleared.
5. The Sun and its planets all spin
in the same direction.
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The Sun
Within the core of the Sun:
temperatures exceed 15,000,000° C
and pressure is 340 billion times the atmospheric
pressure at Earth's surface.
Conditions are so intense that nuclear fusion takes
place creating new elements.
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Nuclear Fusion in the Sun
Four hydrogen nuclei get fused into one helium nucleus,
Accompanied by the emission of neutrinos and release
of energy:
4 H1  He4 + neutrinos + energy
H1 is the nucleus of a hydrogen atom (one proton)
He4 is the nucleus of a helium atom (two protons and
two neutrons)
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Conversion of Mass into Energy
The nucleus of the resulting
helium atom is about 0.7
percent less massive than
the four component protons.
During the fusion of hydrogen, approximately 0.7% of the
mass of hydrogen is converted into energy.
E = mc2
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The Solar Wind
Fast-moving ions can escape the Sun's
gravitational attraction. Moving outward at
hundreds of kilometres/second, these
positive and negative charges travel to
the farthest reaches of the solar system.
They are called the solar wind.
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Solar Prominences
Bursts of solar wind accompany solar prominences
(similar to nuclear explosions) which extend
millions of km into space.
Earth
Solar
Prominence
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Interstellar Distances
• The Sun is massive – 99.9% of mass.
• The planets are relatively minute:
- Jupiter makes up most of the remaining 0.1%.
• The next nearest star appears as a point of light.
• Similarly, from the nearest star, our Sun would appear as
a point of light in the night sky
- the planets of our Solar System would not be visible.
- similarly planets of other stars are not visible to us,
but must exist
[detected by wobbles of star due to gravity of orbiting planets].
• Distances between the stars are enormous.
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A new unit of distance to measure
interstellar space
Light Year:
The distance light travels in a year, travelling at a speed of
300,000 kilometres per second;
1 light-year is equivalent to 9.46053 x 1012 km
( almost ten trillion km).
• The Sun's nearest known stellar neighbour is a star called Proxima
Centauri, at a distance of 4.3 light years away (i.e., 4.3 LY).
• Some Quasars are more distant than 10 billion LY.
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The Solar System is Small
Solar System from a Cosmic Perspective
Facts:
1.
Average distance from the Sun to Neptune is 4.5 x 109 km
2.
Distance from the Sun to the nearest star is 4.1 x 1013 km
(~ 9000 x distance from Sun to Neptune)
3.
The Sun is one of 1022 similar stars.
4.
On a cosmic scale the Solar System is microscopic.
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The Solar System is Large
Solar System from an Earth Perspective
Facts:
1. The Diameter of Earth is 12.8 x 103 km (DEarth)
2.
The distance from the Sun to Earth is 1.496 x 108 km or
about 12,000 x DEarth.
3.
The diameter of Neptune’s orbit is 700,000 x DEarth.
4.
On an Earth scale the Solar System is vast.
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A new unit of distance to measure
interplanetary space
Astronomical Unit (AU) :
The average distance from the Earth to the Sun;
1 AU = 149,597,870 kilometres (~150 million km)
1 LY= 63,240 AU.
We can measure distances within the solar system in units of
AU’s.
e.g., The distance from the Sun to Earth is 1 AU
The distance from the Sun to Mars is 1.5 AU
The distance from the Sun to Venus is 0.72 AU
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