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The Solar System (Planetary Debris)
Charles Modequillo
Aiko Olaer
Planetary Debris
• During the formation of the Solar System not
everything became the planets and the
moons. There are other remnants from the
solar nebula that are called planetary debris.
These are what we know as asteroids,
meteoroids and comets.
ASTEROIDS
Asteroids
• planetary debris made up of chunks of rocks
and metals that orbit around the Sun. They
are also called planetoids
• planetary debris made up of chunks of rocks
and metals that orbit around the Sun. They
are also called planetoids
• compose only a fraction of the Solar System
Types of Asteroids
• C – Type
• S- Type
• M - Type
C- Type
• Carbonaceous (largely carbon, dark)
• Consist 75% of the asteroids
• Outer orbits
S- Type
• Silicate (largely silicon, light)
• Consist 15% of the asteroids
• Inner orbits
M- Type
• Nickel-iron
• Consists about 10% of the asteroids
Examples of Known Asteroids
• Ceres
• Gaspra
• Ida
Ceres
• Largest asteroid
• 940 km diameter
• 1/10,000 of the mass of Earth’s moon
Gaspra
• S-Type asteroid
• Maximum diameter of 20 km
• About 200 million years old
Ida
• S-Type asteroid
• Maximum diameter of 60 km
• About 1 billion years old
COMETS
Comets
• Comets are icy matters that follow elliptical
orbits around the solar system. As they
approach the Sun, comets heat up, emit
radiation and also develop a tail.
Parts of a Comet
Nucleus
• Solid portion of the comet
• 1 to 10 km in diameter
• Density of 100 kg/m3
Coma
• Evaporated gas and dust forming a
halo around the nucleus as the
comet approaches the Sun
Hydrogen Envelope
• Hydrogen gas that surrounds the
coma of the comet and trails along
for millions of miles
Dust Tail
• Up to 10 million km long composed of
smoke-sized dust particles driven off the
nucleus by escaping gases
• Broad, diffuse, curved, less deflected by
solar wind
Ion Tail
• Straight out, blown by solar wind
• Several hundred million km long
composed of plasma and laced with
rays and streamers caused by
interactions with the solar wind
ORBITS
Orbits
• Having a highly elliptical orbit means that
there is point for each comet where it is
closest to the Sun. At this point we call that a
comet is at its perihelion. There is also a point
where the comet is farthest from the sun, this
point is called aphelion.
Orbits
• A period is the time taken by a comet to
travel once around the Sun in its orbit.
Comets are often classified according to
their orbital periods.
Period of Orbits
• Short-period Orbits
• Long Period Comets
Short Period Orbits
• From Kuiper Belt
• Have orbital periods of less than 200 years
• 30 to 50 AU (Astronomical Unit) in diameter
Long Period Orbits
• From Oort Cloud
• Orbits up to 100,000 AU in diameter
• Periods ranging from 200 years to
thousands or even millions of years
• Surrounds Sun in all directions
Kuiper Belt and Oort Cloud
Halley’s Comet
• First predicted by Edmund Halley to
reappear in 1758
• last visible from Earth in the year 1986
• has been orbiting the Sun since 240 BC
Halle-Bopp
•
•
•
•
Discovered in July 1995
Was visible to the naked eye in
Perihelion on April 1, 1997
Period of about 4000 years
METEOROIDS
Meteoroids
• are small bits of rock or metal or ice that are
chipped off asteroids or comets. They are
debris floating in space outside the Earth’s
atmosphere. On the other hand, meteors are
meteoroids on the process of entering the
Earth’s atmosphere. They are also known as
shooting stars.
Meteorites
• are pieces of a meteoroid that successfully
lands on Earth. These meteoroids are the ones
responsible for cratering the inner solar
system.
Types of Meteorites
•
•
•
•
•
Iron
Stony Iron
Chondite
Carbonaceous Chondrite
Achondrite
Iron
• primarily iron and nickel similar to type M
asteroids
Stony Iron
• mixture of iron and stony material like S
type asteroids
Chondite
• similar in composition to the mantles and
crusts of the terrestrial planets
Carbonaceous Chondite
• very similar in composition to the Sun less
volatiles, similar to type C asteroid
Achondrite
• similar to terrestrial basalts, the meteorites
believed to have originated on the Moon
and Mars are achondrites
A very large number of meteoroids enter the
Earth's atmosphere each day. The largest
found meteorite (Hoba, in Namibia) weighs
60 tons.
The average meteoroid enters the atmosphere at between
10 and 70 km/sec. But all but the very largest are
quickly decelerated to a few hundred km/hour by
atmospheric friction and hit the Earth's surface with
very little fanfare. However meteoroids larger than a
few hundred tons are slowed very little; only these large
(and fortunately rare) ones make craters.
Barringer Crater
•
•
•
•
A crater near Winslow, Arizona
Was formed around 50,000 year ago
Formed by a 30-50 meter diameter iron meteor.
Crater is 1200 meters in diameter, 200 meters
deep
Meteor Showers in the Philippines
Geminids
• The Geminids meteor shower is an annual
event. Its recent peak was observed in the
Philippines last December 14th of 2011.
They appear to radiate from the
constellation Gemini.
Leonids
Leonids is an annual meteor shower the generally
begins on Nov 13 and ends on November 17. It
occurs annually at the time of the year when the
Earth passes through streams of debris left
behind by the Tempel-Tuttle comet.
Upcoming Meteor Showers for 2012
Lyrids Meteor Shower
• Will occur late night of April 21 until dawn April
22 and the night of April 22 until dawn of April
23
• rate of 10 to 20 meteors per hour
• outbursts up to 100 meteors per hour
Others
ETA Aquarids
May 5 to 6
Delta Aquarids
July 28 and 29
Perseids
Dawn of August 12 or 13
References:
http://manila-paper.net/geminids-meteor-shower-peak-tonight-december14/21299
http://www.meteorwatch.org/2011/11/11/leonids-meteor-shower-2011/
http://newsinfo.inquirer.net/breakingnews/nation/view/20091105234291/Spectacular-meteor-shower-forecast-on-Nov-17
http://earthsky.org/astronomy-essentials/earthskys-meteor-shower-guide
http://physics.uoregon.edu/~jimbrau/astr121/Notes/Chapter14.html
References:
http://ircamera.as.arizona.edu/NatSci102/NatSci102/lectures/debris.htm
http://astro.unl.edu/classaction/outlines/solarsystemdebris/ss_debris.html
http://en.wikipedia.org/wiki/Comet
http://nineplanets.org/comets.html
http://cse.ssl.berkeley.edu/segwayed/lessons/cometstale/frame_orbits.html
References:
http://www.bobthealien.co.uk/cometshal.htm
http://nineplanets.org/meteorites.html
http://stardate.org/astro-guide/ssguide/meteorites
http://en.wikipedia.org/wiki/Hoba_meteorite