Download PowerPoint Presentation - Welcome to Modern Astronomy Fall 2003

Welcome to Modern Astronomy
Fall 2007
• Initial pleasantries,
who I am, who you
are
• This should be the
most interesting
course you take in
college
• National Solar
Observatory
The Sun is more interesting some times
(wait 5 years)
Example 1: The “Dark Matter”
Example 2: Arcturus (see it
tonight)
Distance: 37 light years
Arcturus (bright star overhead) as
an immigrant from another galaxy
The Milky
Way (and
other
galaxies)
catch and
devour small
galaxies
Details from the Syllabus
The Sky Tonight
• The Sun sets (7:48 PM)
• Arcturus and Spica in the
west (stars)
• Antares (star) and Jupiter
in the south
• Vega (star) and the Milky
Way overhead
• The Andromeda Nebula
in the east
• Constellation of Scorpius
• Constellations Internet
Link
Tomorrow Morning: Total Eclipse of the
Moon
Timetable for
lunar eclipse
An Overview of the Solar System
Size scales in the solar system
demo
• Basic unit: 1 meter
• 1 kilometer = 1000 meters = 0.6214 miles
• Diameter of Earth: 12756 kilometers (~ LA to
Sydney)
• Closest object in space: Moon, 384,000 km
average distance
• Most prominent object is astronomy: Sun, 149.6
million kilometers; 1 Astronomical Unit
The Sun
Facts about the Sun
• Distance: 149.6 million kilometers = 1.496E+11 meters =
1 astronomical unit
• Radius = 695,990 kilometers = 6.960E+08 meters (109
times radius of Earth)
• If Earth were scaled to 1 foot globe size, the Sun would
extend from goal line to 30 yard line at Kinnick stadium
• The Sun, not the planets (including Earth) is the dominant
object in the solar system