Chapter 2 Flashcards
(41 cards)
longitude is defined to be 0 degrees along the ______
Prime Meridian
The altitude of the celestial pole in your sky is equal to your_____?
Latitude
The constellations along the ecliptic make up what we call the ______?
Zodiac
Summer solstice ____
Winter solstice______
Spring Equinox_____
Fall equinox ______
(June)
(Dec.)
(March)
(September)
How long is the lunar phases?
29.5 days
Umbra
This is were the sunlight is completely blocked
Penumbra
Where sunlight is only partially blocked
Parallax
Depends on distance, with nearer objects exhibiting greater parallax than more distant objects
Constellation is?
Region of the sky with well-defined borders; the familiar patterns of stars merely help us locate the constellations
What is a galaxy cluster?
groups of galaxies with more than a few dozen members
Speed of light travels ____
300,000Km per second or 10 trillion for year
The sun outweighs all the planes by a factor of ____?
1000
Big Bang occurred roughly ____ years ago
14 billion
our local solar neighborhood move essentially at ____
Random
Virtually every galaxy outside the Local Group is moving ____ from us.
away
The more distant the galaxy, the _____ it appears to be racing away
faster
There is no edge to the universe we think (True, or False?)
True
What is the Copernican revolution?
Showed us that Earth is not the center of the universe, but rather just one planet orbiting the sun.
Who was Tycho
Known as best naked eye observer. He failed to explain the motion of planets.
Who was Kepler
Discovered that planets did not travel in circle, but elliptical. Studied Mars
Kepler’s Three Laws:
1) elliptical orbits with sun as focus
2) As planet moves around orbit it sweeps equal areas in equal time.
3) More distant planets orbit the Sun at slower average speed. P^2=a^3
Tentative explanation, or Hypothesis is?
Sometimes called an educated Guess
Planets usually move from _____ to _____
West to East
Occam’s razor
Rule of picking the simpler explanation.
