Dr. Walter Freeman
September 27, 2016
Calendars and the Sky
In ancient China, the
Chinese used sundials to
keep time. The sundial
has three parts: the round
rock, the needle and the
marks on the round rock.
The principle of sundia
Astronomy Flashcards 5
The Milky Way Galaxy is one of many billions of galaxies in the universe
Variable stars such as Cepheid variables are used in what important measurement in astronomy measure
of the distance to stars
Cepheid variables are invaluable
umbra the darkest part of a shadow
penumbra lighter shadow of an eclipse
Solar Eclipse occurs when the Moon passes directly between the Sun and Earth and casts a shadow over
part of Earth
lunar eclipse occurs when the Earth passes di
Astronomy flashcards 1
What is the date of the winter solstice? December 21.
What is the date of the Spring/Vernal equinox? March 21.
What is the date of the summer solstice? June 21.
What is the date of the Fall/Autumal equinox? September 21.
ASTRONOMY Flashcards 4
neap tide a tide with the least difference between high and low tide that occurs when the sun and
moon pull at right angles to each other.
(first and last quarter moon phases)
spring tide a tide with the greatest difference betwee
The most direct piece of information we get from an emission or an absorobtion spectrum of a distant
object is its composition
The most direct piece of information we get by measuring the Doppler shift in the spectral lines of a
distant object is its. Spe