Earth - PowerPoint PPT Presentation

1 / 27
About This Presentation
Title:

Earth

Description:

Examples: Betelgeuse 0.58 Venus -3.7 Sirius -1.47 Full Moon -12.6 Polaris 2.01 Sun -26.7 Pluto 13.7 Dimmest object seen with Hubble ST 30 What affects brightness? – PowerPoint PPT presentation

Number of Views:69
Avg rating:3.0/5.0
Slides: 28
Provided by: JeffandRh2
Category:
Tags: betelgeuse | earth

less

Transcript and Presenter's Notes

Title: Earth


1
Earth Space SciencePart 1 Stargazing
  • 1.1 Measuring the Universe

2
Making Unmanageably BIG Numbers Manageable
  • Two Methods
  • Scientific Notation
  • (Speed of Light 300,000,000 m/s 3.0 x 108m/s)
  • Bigger Units
  • (Speed of Light 300,000,000 m/s 300 Mm/s)

3
1. Scientific Notation
  • General Form

x 10
Exponent of places to move decimal
Number between 1 and 10
4
Examples of Scientific Notation
  • World Population 6,600,000,000
  • 6.6 x 109
  • US Population 301,000,000
  • 3.01 x 108
  • Illinois Population 1.28 x 107
  • 12,800,000
  • Bloomington Population 7.097 x 104
  • 70,970

5
A Video of Scientific Notation
  • Awaits you here.

6
Whos biggest?
  • Rank the following items in order of INCREASING
    size (smallest ? biggest)

7
2. Bigger Units
  • Metric Prefixes
  • Kilo- 1,000
  • Downs ? Wrigley Field 230,000 m
  • 230 km
  • Mega- 1,000,000
  • Downs ? Moon 384,000,000 m
  • 384 Mm
  • Giga- 1,000,000,000
  • Downs ? Sun 150,000,000,000 m
  • 150 Gm

8
Measuring Distance
9
Astronomical Unit (AU)
  • Distance from Earth to Sun.
  • Useful for measuring distances within solar
    system.
  • 1 AU 1.5 x 1011 m 93 million miles
  • Sun ? Earth 1 AU
  • Sun ? Mars 1.52 AU
  • Sun ? Jupiter 5 AU

10
Light year (ly)
  • Distance light travels in 1 year.
  • Useful for measuring distances between stars.
  • 1 ly 9.5 x 1015 m 63,200 AU 5.9 trillion
    miles
  • Downs ? Alpha Centauri 4.4 ly

11
A Comparison of Distance Units(Not even close to
scale)
12
Review
  • The distance to the moon is 384,000,000 m.
  • What is this in scientific notation?
  • 3.84 108 m
  • How many kilometers is this?
  • 384,000 km

13
More Review
  • What unit would you use to measure the distance
    from Earth to the planet Saturn?
  • a) Astronomical Unit b) light year
  • What unit would you use to measure the distance
    to Betelgeuse, a star in the constellation Orion?
  • a) Astronomical Unit b) light year

14
Measuring Mass
15
Mass vs. Weight
  • Mass Amount of stuff in an object
  • An objects mass is the same anywhere in the
    universe.
  • Weight How strongly gravity pulls on an object
  • An objects weight varies from planet to planet

16
More Mass vs. Weight
  • On Earth
  • Mass of moose 720 kg
  • Weight of moose 1200 pounds
  • On Moon
  • Mass of moose 720 kg
  • Weight of moose 200 pounds

17
Units of Mass
  • Kilogram (kg)
  • 1 kg 2.2 pounds
  • Example Mass of an astronaut is 90 kg.

An Official Kilogram 1 ½ x 1 1/2 cylinder
of platinum and iridium
18
Another Unit of Mass
  • Earth Mass
  • 1 Earth mass 6.0 x 1024 kg
  • Useful for measuring masses of planets
  • Example Mass of Jupiter is 318 Earth Masses

19
And Another Unit of Mass
  • Solar Mass
  • 1 Solar mass 2 x 1030 kg 330,000 Earth
    Masses
  • Useful for measuring masses of stars
  • Example Mass of Betelgeuse is 14 Solar Masses

20
Measuring Brightness
21
Measuring Apparent Magnitude, m (aka
Brightness)
  • Hipparchus (Greece, 200 BC)
  • Ranked stars on 6-point scale
  • 1st Magnitude 20 brightest stars
  • 2nd Magnitude Next brightest
  • etc.
  • 6th Magnitude Faintest stars visible with naked
    eye
  • Similar method used today!

22
Todays Apparent Magnitude Scale
  • Decimals and numbers outside of 1-6 range OK
  • Each increase of 1 in magnitude is an increase of
    2.5x in brightness
  • Add scale!
  • Examples

Betelgeuse 0.58 Venus -3.7
Sirius -1.47 Full Moon -12.6
Polaris 2.01 Sun -26.7
Pluto 13.7 Dimmest object seen with Hubble ST 30
23
What affects brightness?
  1. Distance from us
  2. Size of star
  3. Temperature of star

24
Measuring Temperature
25
3 Scales to Use
  • Fahrenheit
  • Celsius
  • Kelvin

26
A Comparison of Temp. Scales
Fahrenheit Celsius Kelvin
Origin ??? Who knows??? Water Theory
Significance of 0 degrees Nuttin Water freezes Lowest possible temperature (absolute zero)
Freezing point of water 32o F 0o C 273 K
Boiling point of water 212o F 100o C 373 K
27
Examples of Temperatures
  • Average Earth Temperature
  • 58.3o F 14.4o C 287.4 K
  • Surface of Sun
  • 10,800o F 6000o C 6270 K
  • Core of Sun
  • 27 million o F 15 million o C 15 million K
  • Outer Space
  • -454o F -270.3o C 2.7 K
Write a Comment
User Comments (0)
About PowerShow.com