of 18
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AnnouncementsOrigin of the solar system
Galaxies and molecular clouds
Solar disk
What meteorites tell us
Inner versus outer planets
Three-part Earth
Origin of atmosphere and hydrosphere
Chapters 1, 2: Cosmic Beginnings
Next lecture: Chapter 3
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AnnouncementsOrigin of the solar system
Galaxies and molecular clouds
Solar disk
What meteorites tell us
Inner versus outer planets
Three-part Earth
Origin of atmosphere and hydrosphere
Chapters 1, 2: Cosmic Beginnings
Next lecture: Chapter 3
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Galaxy similar to the Milky Way: 200
billion stars!
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In this picture of the Eagle
Nebula taken by the HubbleSpace Telescope, we can
see star birth in action. Each
finger-like protrusion from
the molecular cloud is a
dense cluster of gas and
dust that will become a star
or solar system.
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Star swarm, formerly a
molecular cloud
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Announcements
Origin of the solar system
Galaxies and molecular clouds
Solar disk
What meteorites tell us
Inner versus outer planets
Three-part Earth
Origin of atmosphere and hydrosphere
Chapters 1, 2: Cosmic Beginnings
Next lecture: Chapter 3
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Pictoris, a solar disk becoming a solar
system. Image taken at Mount Palomar
observatory. The star itself has been
blocked out so that its brightness does
not swamp the dim dust ring. The dust
ring will condense to become asteroidsand planets.
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Hubble pictures of
stars with girdles
of dark dust that
probably will form
new planet
systems. Thebright green
streaks emanating
upwards show the
early, violent solar
wind.
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Announcements
Origin of the solar system
Galaxies and molecular clouds
Solar disk
What meteorites tell us
Inner versus outer planets
Three-part Earth
Origin of atmosphere and hydrosphere
Chapters 1, 2: Cosmic Beginnings
Next lecture: Chapter 3
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We also learn
about the early
solar system
from studyingmeteorites, some
of which
represent
material from
the earliest
times. Everytime we study a
meteorite we
might find a new
clue, or better
information.
Science is a
humanenterprise. It is
never perfect,
and never
complete.
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This rare type of meteorite
has iron and a green
mineral called olivine, two
important components of
the inner Earth. It
probably reflects a small
planet that was destroyedearly in the solar system,
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Announcements
Origin of the solar system
Galaxies and molecular clouds
Solar disk
What meteorites tell us
Inner versus outer planets
Three-part Earth
Origin of atmosphere and hydrosphere
Chapters 1, 2: Cosmic Beginnings
Next lecture: Chapter 3
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Inner Planets
Outer Planets
Inner vs. Outer Planets
Inner planets are small and high
density, outer large and low density.
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Inner vs. Outer PlanetsThousands of asteroids occupythe gap between inner and outer
planets. Theres not enough
material there to form a planet of
their own, however.
Image from nasa.gov
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Image credit: Joe Tucciaronehttp://starchild.gsfc.nasa.gov
Were not sure of how the
Moon formed, but the most
popular current theory is that
the Earth was hit by another
small planet early in its history.
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Announcements
Origin of the solar system
Galaxies and molecular clouds
Solar disk
What meteorites tell us
Inner versus outer planets
Three-part Earth
Origin of atmosphere and hydrosphere
Chapters 1, 2: Cosmic Beginnings
Next lecture: Chapter 3
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Three major
Earth divisions
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Announcements
Origin of the solar system
Galaxies and molecular clouds
Solar disk
What meteorites tell us
Inner versus outer planets
Three-part Earth
Origin of atmosphere and hydrosphere
Chapters 1, 2: Cosmic Beginnings
Next lecture: Chapter 3
