Download How our Solar System (and Moon) came to be

How our Solar System (and
Moon) came to be…
Learning Objectives
• Be able to explain
– How our solar system and moon came to be
• IRAS launched into orbit 1983
– Direct evidence that solid matter exists
around stars
– Can cloud particles be early stages in the
development of the planets?
• Theory emerged: Planets
form while star is forming
Rotating Nebula Theory
• Solar system began as collection of dust and
gases (nebula)
• This nebula made up of mainly hydrogen and
helium gases
– Also some solid
particles like iron, rock, ice
• These particles came from massive explosion
of an older star called supernova
– Supernova = star in it’s final phase of life, when it
explodes it is many time it’s original size
– Particles had moved closer together due to gravity
• As nebula collapsed, internal pressure and
temperature increased and more particles
were attracted to nebula
• Eventually temperature and pressure in the
gas cloud was great enough for a complex
reaction to begin
• Reaction caused release of large amounts of
energy, creating massive explosions
• At core of nebula, our Sun began to develop
• Early stages of the nebula began to rotate due
to gaseous material
• The speed of rotation became too great to
hold al of matter together at center
• Matter spread out from center like pancake
• Bulge remained at center forming the Sun
• While sun formed, smaller clumps of cooler
matter called protoplanets began to appear in
outer regions of nebula
– Protoplanets condense to form planets of our solar
system getting larger as they pick up debris
• Likely how gas giants came to be
• Sun flared up in a sudden burst of energy
– Caused helium and hydrogen into the outer
regions
– Dense chunks of solid matter left behind
• Formation of inner planets
Other bodies in Solar System
• Asteroids
– Rocky object, smaller than a
planet that orbits the sun
– They orbit the sun between
Mars and Jupiter (asteroid belt)
– Asteroids often collide and
break into pieces called
meteoroids
– “Falling stars” are meteoroids
becoming meteorites as they
pass into earth’s atmosphere
• Meteors and Meteorites
– Meteor – lump of rock or metal that falls from
space towards earth’s surface
– Meteorite – a meteor that is large enough to
survive entry and reach the surface of the earth
• Separated into 2 broad groups: stones and irons
• Impact of meteorite creates a crater
• Comets:
– Usually name after their discoverers
– Are made of rock dust and icy matter left over
from the formation of the solar system
– Ancients believed comets to be the soul of a hero
or king on its way to heaven or messengers of
disasters
• Gas pushed out behind nucleus (Tail)
• Nucleus (rocky and metallic particles coated with
H20, ammonia, methane and CO2
• Come – formed as frozen substances begin to
vapourize
Formation of our Moon
• Moon about 4.5 billion years old…. Similar in
age to the Earth
• How?? Why??
Big Splash Theory
• Large object (size of Mars) collided with Earth
• Collision caused high temperatures and
pressures
– This ended up in materials like iron to become
part of Earth’s core
• Less dense materials blasted into space
– Ended up orbiting around the Earth
• Materials began to condense and gravitate
into each other through more heat and
pressure