Transcript Scale of the Cosmos ppt.

Scale of Earth’s Systems
https://www.youtube.com/watch?v=Zr7wNQw12l8
Journey tot eh Edge of the Universe
The Universe- the largest SYSTEM
What is the Universe?
How large is the universe?
How many galaxies are in the universe?
Section 28.4 on page 631
http://htwins.net/scale2/
Powers of Ten
http://www.youtube.com/watch?v=0fKBhvDjuy0
Cosmic Zoom activity
http://aspire.cosmic-ray.org/Labs/CosmicZoom/
Scientific Notation
Convenient way to write extremely large or
extremely small numbers
 Has 2 parts: base and exponent
 Base exponent
 Examples: 103 = 10x10x10 = 1000
10-2 = 1/10x1/10 = 0.01
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Units to Measure the Universe
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Astronomical Unit = AU
Unit of Length
Average distance between Earth
and Sun
Ave. 93,000,000 miles
Light Year = LY
The DISTANCE light travels in one
year
Distance = speed of light x 1 year
Light years is a DISTANCE
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Speed of light: 300,000 km/sec.
(186,000 miles/sec)
Times 86,400 seconds in a day
 Times 365 days in a year
 10 trillion kilometers!
 10,000,000,000,000 km
 1013 km
 Or about 6 trillion miles!!!
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Lag Time
Because the sun is 93,000,000 miles away
from earth,
 It takes time for the sunlight to travel that
distance (even at a speed of 186,000 mi/s)
 It takes 8 minutes for the sunlight to reach
earth.
 So…. The light we see from a star that is
1500 ly away, left that star 1500 years
ago!
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Orion Nebula
Nebula of gas, and stars. In the constellation Orion.
1500 light years away.
1344 ly x 6 trillion miles = ??
Horsehead