Transcript What else is in our solar system, besides the sun, the

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YIKES
What else is in
our solar system,
besides the sun, the planets, and
their moons
?
#1: Asteroids
Asteroids: are large rocks in orbit
around the Sun
•Between size of meteoroids and
dwarf planets
951 Gaspra -18x9km
(first asteroid close-up)
Why aren’t
they round?
Why asteroids are cool
• They are leftovers from the formation of the
solar system
– Studying them tells us about the origin of the
solar system and the Earth
Birthplace of Asteroids
• The Asteroid Belt: between Jupiter and Mars.
• Asteroids can collide and get redirected
toward Earth.
• Note the Belt’s size
2nd birth place of Asteroids: Kuiper Belt
• Another band of
asteroids outside outer
planets.
– What is the pink band? 
Figure: Objects in the main belt are colored green, while scattered objects are
colored orange. The four outer planets are blue. Neptune's few known
Trojan asteroids are yellow, while Jupiter's are pink. The scattered objects
between the Sun and the Kuiper belt are known as centaurs. The scale is in
astronomical units. The pronounced gap at the bottom is due to
obscuration by the band of the Milky Way.
Why isn’t Pluto a “planet”?
Meteor Crater is 2.5 miles in
circumference. It was made by a
meteor 150 ft. in diameter
travelling at 65,000 miles/hr.
Most famous asteroid:
A 10 km asteroid wiped out 50% of the
Earth’s species, including dinosaurs, 65 mya
ash from impact blanketed the Earth
…then blackness…then coldness
The resultant Chicxulub Crater is 110 miles in diameter
Deep Impact Trailer
Extinction Level Asteroid
• What is the best way for • If only some can
humanity to survive a
survive, say 300, create
killer asteroid?
a plan for deciding who
lives.
#2: Comets
•A comet is an icy, dusty body orbiting the
sun; a.k.a. “dirty snowball”
Comets McNaught 2007 and Hale
Bopp 1998
Comet Anatomy:
• Note the two distinct tails: light blue for gas
(ion), grey for dust
• What is the tail(s)
direction relative to the sun?
• Relative to motion?
Comet orbit
• Watch 2 animations of comet’s path around the
sun in the following link:
http://www.classzone.com/books/earth_science/terc/content/visualizations/es2706/es2706page01.cfm?chapter_no=visualization
Notice:
– Orbit shape:
– Speed:
– Tail direction:
When does the comet move the
fastest? The slowest?
When does the comet move the
fastest? The slowest?
Fastest at
perihelion
Slowest at
aphelion
Comet source:
• The Oort cloud is the birthplace of all comets.
– It is a shell of ice dust
FUN FACTS:
– nearly a quarter of the distance to Proxima
Centauri, the nearest star to the Sun.
– Pluto is less than one thousandth the Oort cloud's
distance.
– the Oort cloud defines the gravitational
boundary of the Sun.
The Oort Cloud is not planar
#3: Meteoroids
• A meteoroid is a small sand to boulder sized
particle of debris in the Solar System.
VS.
• Meteor: The visible path of a meteoroid that
enters the atmosphere, a.k.a. "shooting star“
VS.
• If a meteoroid reaches the ground, it is then called
a meteorite.
Meteor shower source:
• when the Earth passes through a trail of
particles left by a comet. Particles burn up in
atmosphere due to _____, glowing brightly
This pic: 2
meteors in a
shower.
What’s in the
middle of the
picture?
#4: What else is in our
solar system?
#4: What else is in our
solar system?
To Learn More…
About
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Minor Planets
Solar System
Sun
Meteoroids
951 Gaspra
Trojan asteroids
Centaurs
Astronomical units (AU)
Milky Way
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Small Solar System Body
Comet coma
Comet tail
Comet’s nucleus
Elliptical orbits
Oort cloud
Meteorite
Meteor shower
Just Click!