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Origin of the Oceans I
Our Solar System
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Solar System?
To begin our study of the oceans, we must understand why they exist. Fundamental to this question is whether every planet has oceans, and, if not, why Earth does.
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Copernicus• Nicholas Copernicus (1473-1543) liked the heliocentric
system of Aristarchus. He recognized that retrograde motion could be explained by the different times it takes the Earth to Orbit the sun compared to the other planets. Because Mars has a much greater Retrograde motionthan other planets it must be closer than Jupiter and Saturn.
• Copernicus offered two major hypotheses– Planets moved in circular orbits around the Sun– The Earth spins on its axis
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Retrograde Motion
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Retrograde Motion
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Brahe• After Copernicus’s ideas were published in 1543,
there were many skeptics. One was Tycho Brahe(1546-1601). He established an observatory in Denmark to mark detailed measurements of the planets in order to disprove Copernicus. (There were no telescopes at this time). These were the most accurate measurements on the movements of the planets upto date.
• He hired a mathematician Johannes Kepler to do astronomical calculations and after a while he suspected that Copernicus might be correct. He suspected that some force exerted by the Sun which exerted a control on the planets (this force is gravity but it had not been discovered at this time).
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Kepler• Kepler discovered three laws that describes planetary motions.
– The Law of the Ellipse- The orbit of a planet is described by an ellipse, and is not circular.
– The law of equal areas- A line drawn from the planet to the Sun sweeps out equal areas in equal times. A consequence of this is that a planet moves rapidly when close to the Sun and slower the further away it is.
– The law of orbital harmony- For any planet, the square of the orbital period is proportional to the cube of the planet’s distance from the sun. The period of the Earth is 365.24219 days. (Leap year). The extra .24 days means that every 4 years we add an extra day. In addition every 450 years we need to day a further day.
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Galileo• Galileo (1564-1641) constructed a small telescope and
with it made observations which sealed the fate of the geocentric universe. – He observed the rotation of planets around Jupiter (i.e. the Earth
could not be center of the universe) and that Venus went throughphases like the moon which meant that it did not orbit around the Earth, but the Sun.
– Galileo also made observations about force. Motion is a result of a force and will only change if other force is applied. Galileo concluded that a force pulls all bodies with the same acceleration.
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Newton• Issac Newton (1642-1727) pulled all the pieces
together. He concluded that the Moon moves around the Earth because it exerts a small force on the Moon which causes it to move towards the Earth. The was the force which Kepler thought might be magnetism. The law of gravity states that every body in the Universe attracts every other body.
• F= G M1M2/ R2.
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Time Scales of Formation of the Universe
• Appearance of Space, Time, and Energy from single point– 5.39X10-44s (expansion to 1.6X10-35m)
• Gravity– 10-43s
• Inflation of Universe to 10cm– 10-32s, still 1027K
• Formation of atoms– 800,000y (Temperature = 3000K)
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Formation of a Solar System
• Coalescence of dust and particles– Rotation– Heat– Gravity
• Spinning disc of material– Differentiation of particles
• Coalescence of planetesimal objects and asteroids
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Formation of a Solar System
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Planetary formation
• During coalescence of planets, each one was developing unique characteristics– Original nebulas had an abundance of
different elements and some molecules– As planets coalesced and cooled,
gases escaped• Smaller planets lost gases first
– Larger planetesimals created more internal heat and trapped it deep in their cores
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Planetary Differentiation
• Result is that each of the nine planets has unique characteristics– (bear in mind that
planetary and solar system formation is an on-going process)
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Solar System: SunMass(kg): 1.989 e+30
Mass (earths): 332,830
Eq. radius (km): 695,000
Eq. radius (Earth = 1): 108.97
Mean density (g/cm3): 1.410
Rotational Period (Earth days): 25-36
Escape velocity (km/s): 618.2
Luminosity (erg/s): 3.827e+33
Magnitude (Vo): -26.8
Mean Surface Temperature (oC): 6000
Age (billion years): 4.6
Principal Chemistry (%)Hydrogen: 92.1Helium: 7.8Oxygen: 0.061Carbon: 0.03Nitrogen: 0.0084Neon: 0.0076Iron: 0.0037Silicon: 0.0031Magnesium: 0.0024Sulfur: 0.0015
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
The Sun
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Life Cycle of a Star
• Energy produced by fusion- joining of two small nuclei to form a larger nucleus plus energy– 2H + 2H = He (two Deuteriums fuse to Helium)
• When Hydrogen is spent, helium fuses to heavier elements (carbon, beryllium, oxygen, etc.)– Temperature requirement is high for this type of
fusion• Eventually star explodes (supernova) and
elements are available to rest of universe
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Mature Star – Red Giant
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Over-mature Star – Close to Supernova Event
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
The Planets: MercuryMass(kg): 3.303 e+23
Mass (earths): 5.5271e-2
Eq. radius (km): 2439.7
Eq. radius (Earth = 1): 3.8252e-1
Mean density (g/cm3): 5.42
Mean distance from sun (km): 57,910,000
Mean distance from sun (Earth = 1): 0.3871
Rotational Period (Earth days): 58.6462
Orbital Period (days): 87.969
Mean orbital velocity (km/s): 47.88
Mean Surface Temperature (oC): 179
Maximum Surface Temperature (oC): 427
Minimum Surface Temperature (oC): -173
Atmosphere componentsHeliumSodiumOxygen
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
The Planets: VenusMass(kg): 4.689e+24
Mass (earths): 0.81476
Eq. radius (km): 6051.8
Eq. radius (Earth = 1): 0.94886
Mean density (g/cm3): 5.25
Mean distance from sun (km): 108,200,000
Mean distance from the sun (Earth = 1): 0.7233
Rotational Period (Earth days): -243.0187
Orbital Period (days): 224.701
Mean orbital velocity (km/s): 35.02
Mean Surface Temperature (oC): 482
Atmospheric pressure (bars): 92
Atmosphere componentsCarbon dioxide (96%)Nitrogen (3+%)trace amounts of sulfur dioxide, water vapor, carbon monoxide, argon, helium, neon, hydrogen chloride, hydrogen flouride
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
The Planets: EarthMass(kg): 5.976e+24
Mass (earths): 1
Eq. radius (km): 6378
Eq. radius (Earth = 1): 1
Mean density (g/cm3): 5.515
Mean distance from sun (km): 149,600,000
Mean distance from the sun (Earth = 1): 1
Rotational Period (days): 0.99727
Rotational Period (hours): 23.9345
Orbital Period (days): 365.256
Mean orbital velocity (km/s): 29.79
Mean Surface Temperature (oC): 15
Atmospheric pressure (bars): 1.013
Atmosphere componentsNitrogen (77%)Oxygen (21%)
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Earth’s Peculiarities
• Rotation of Earth causes it to bulge at center (equator)
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Important Elements Differentiated during Earth’s Formation
• Elemental radiometric clocks –– Uranium– Thorium
• Radioactively unstable– Parents decay into daughters– If we know the rate of decay and the initial
composition of the daughters, we know the age of a substance
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Formation of Water on Earth
• Hot gases of newly formed compounds escaped the solid earth, trapped by gravity, and condensed when cooled
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Important Elements Differentiated during Earth’s Formation
• Water – H2O!– Very important to
• Life• Weather• Habitability of Planet Earth
• Water formed on other planets– What form?– Did it stay?
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Life on Mars?
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Life on Mars?
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
The Planets: MarsMass(kg): 6.421e+23
Mass (earths): 1.0745e-1
Eq. radius (km): 3397.2
Eq. radius (Earth = 1): 5.3264e-1
Mean density (g/cm3): 3.94
Mean distance from sun (km): 227,940,000
Mean distance from the sun (Earth = 1): 1.5237
Rotational Period (days): 1.026
Rotational Period (hours): 24.6229
Orbital Period (days): 689.98
Minimum Surface Temperature (OC): -140
Mean Surface Temperature (oC): -63
Maximum Surface Temperature (oC): 20
Atmospheric pressure (bars): 0.007
Atmosphere componentsCarbon dioxide (95.32%)Nitrogen (2.7)Argon (1.6)Oxygen (0.2)Carbon Monoxide (0.7)Water, Neon, Krypton, Xenon, Ozone
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Did Mars Have Water?
• Mars Rover Program (NASA)
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Did Mars Have Water?
• If so, what happened to it?
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
The Outer Planets: JupiterMass(kg): 1.9e+27
Mass (earths): 3.1794e2
Eq. radius (km): 71492
Eq. radius (Earth = 1): 11.2
Mean density (g/cm3): 1.33
Mean distance from sun (km): 778,330,000
Mean distance from the sun (Earth = 1): 5.2028
Rotational Period (days): 0.41354
Orbital Period (days): 4332.71
Mean Orbital Velocity (km/s): 13.07
Mean Cloud Temperature (oC): -121
Atmospheric pressure (bars): 0.7
Atmosphere componentsHydrogen (90%)Helium (10%)
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
The Outer Planets: SaturnMass(kg): 5.688e+26
Mass (earths): 9.5181e1
Eq. radius (km): 60,268
Eq. radius (Earth = 1): 9.4494e0
Mean density (g/cm3): 0.69
Mean distance from sun (km): 1,429,400,000
Mean distance from the sun (Earth = 1): 9.5388
Rotational Period (hours): 10.233
Orbital Period (years): 29.458
Mean Orbital Velocity (km/s): 9.67
Mean Cloud Temperature (oC): -125
Atmospheric pressure (bars): 1.4
Atmosphere componentsHydrogen (87%)Helium (13%)
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Moons of Saturn and Jupiter
Jupiter:63 moonsDiameter of Ganymede = 0.4(Earth)
Saturn:60 moonsRings are gravitationally trapped debris
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
The Outer Planets: UranusMass(kg): 8.686e+25
Mass (earths): 14.5
Eq. radius (km): 25.559
Eq. radius (Earth = 1): 4.0074
Mean density (g/cm3): 1.29
Mean distance from sun (km): 2,870,990,000
Mean distance from the sun (Earth = 1): 19.19
Rotational Period (hours): -17.9
Orbital Period (years): 84.01
Mean Orbital Velocity (km/s): 6.81
Mean Cloud Temperature (oC): -125
Atmospheric pressure (bars): 1.2
Atmosphere componentsHydrogen (83%)Helium (15%)Methane (2%)
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
The Outer Planets: NeptuneMass(kg): 1.024e+26
Mass (earths): 1.7e1
Eq. radius (km): 24,746
Eq. radius (Earth = 1): 3.8799
Mean density (g/cm3): 1.64
Mean distance from sun (km): 4,504,300,000
Mean distance from the sun (Earth = 1): 30.0611
Rotational Period (hours): 16.11
Orbital Period (years): 164.79
Mean Orbital Velocity (km/s): 5.45
Mean Cloud Temperature (oC): -193 to -153
Atmospheric pressure (bars): 1-3
Atmosphere componentsHydrogen (85%)Helium (13%)Methane (2%)
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Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Pluto – Planet or Not?
• Pluto and moon, Charon, are a binary system
• Other objects in the Kuiper belt are larger
• Recognition based in revolution plane of Neptune
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Summary• There is one water planet – Earth• Planetary formation differentiated
elements each planet contains• Earth and Venus are very similar• Mars once had water, evidenced by latest
research• The Outer Gaseous Planets are very
different from the Rocky Inner Planets
Professor Rosenheim EENS/EBIO 223
Introductory Oceanography
Summary
• Scientific Notation!
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