Chapter 2 Flashcards
The sun’s ___________ is zero on the vernal equinox or autumnal equinox, so the sun is above the horizon for exactly _____ hours.
Declination, 12
What does the term equinox mean?
Equal night
What does the term solstice mean?
Sun stop
Anyone observing from the ______ Circle will experience 24 hours of sunlight on the summer solstice.
Arctic
In the Northern Hemisphere, days are longer in the ______ and ______ seasons, and shorter in the _______ and _______ seasons.
Spring/Summer, Fall/Winter
The moon orbits roughly in the ______, not the celestial equator.
Ecliptic
When will the first quarter moon make its highest arc in the sky?
On the spring equinox
There are two kinds of eclipses: (1) A ______ eclipse, when the moon’s shadow falls on the earth, and (2) a ______ eclipse when the earth’s shadow falls upon the moon.
Solar, Lunar
The term ______ is the generic term for the two points of intersection on any two great circles.
Node
The configuration of the sun, moon, and earth is about the same every 18.031 years and is called the _______ cycle.
Saros
The earth actually has two shadows. A darker inner shadow called the _______ and a lighter outer shadow called the _______.
Umbra, penumbra
During a total solar eclipse, the bright surface of the sun (the _______) is completely blocked by the moon
Photosphere
Any given spot on the earth experiences a total solar eclipse once every ______ years or so.
400
When the moon is farther from the earth, it appears smaller than the sun, and when it passes directly in front of the sun it leaves a thin ring or __________.
Annulus
The moon seems to wobble a bit from week to week, which is called ________.
Libration
Planets orbit the sun in slightly ______ paths with the sun at one focus of the ellipse.
Elliptical
The _________ planets are Mars, Jupiter, Uranus, and Neptune
Superior
__________ is when a planet is behind the sun.
Conjunction
All the planets orbit the sun in the same direction: ___________.
Counterclockwise
______ and __________ are the inferior planets whose orbits lie closer to the sun than earth does.
Mercury, Venus
A ________ transit is when Mercury or Venus cross directly in front of the sun during inferior conjunction.
Solar
Comets are icy objects and generally have _________ orbits.
Elliptical
Meteor showers are generally caused by debris left behind by a ________.
Comet
The most impressive, reliable meteor shower is the _______ meteor shower, occurring around August 12th each year.
Perseid
The sun traces out a thin figure-eight shape across the sky with each day, which is called _________.
Analemma
The constellation in which the sun is found at the equinox shifts with time. This phenomenon is called the _______________________.
Precession of the equinoxes
