astronomy 1001; test 1
Consider a time when Mars is in the middle of one of its periods of apparent retrograde motion. During this time, Mars appears _____ in our night sky and crosses the meridian around _____
brightest, midnight
The moon must be _____ for a lunar eclipse
full
Nearby objects have a ____ parallax; distant objects have a ____ parallax
large, small
The distance light travels in one year
light year
Which of the following would you expect to have seasons more like earth? -Jupiter (tilt=3.1) -Mars (tilt=25.2) Uranus (tilt=97.9)
mars
During the waning gibbous phase, how much of the illuminated moon can we see?
more than half
Elipses occur when the line of nodes... and we have a... or a ...
points toward the sun, full moon, new moon
The apparent west-to-eat motion (over the course of many nights) of an object relative to the stationary background stars
prograde motion
If a star rises at 7:36 one night, when will it rise the next night?
slightly earlier; around 4 minutes
You look to the east and see a solar eclipse rising above the horizon. What time of day is it?
sunrise
The amount of sunlight at a given location changes over the year depending on
where you are located on the Earth
The Earth is closer to the sun in the
winter than it is in the summer
One kilometer equals how many miles?
0.62 miles
What are the phases of the moon?
1. New Moon 2. Waxing Crescent 3. First Quarter 4. Waxing Gibbous 5. Full Moon 6. Waning Gibbous 7. Third Quarter 8. Waning Crescent
What are the five types of eclipses?
1. Total Lunar 2. Partial Lunar 3. Total Solar 4. Partial Solar 5. Annual Solar
One meter equals how many centimeters?
100 centimeters
How many meters are in one kilometer?
1000 meters
One meter equals how many millimeters?
1000 millimeters
Every month, a constellation rises
2 hours earlier
How many hours long is a sidereal day?
23 hours and 56 minutes
How many hours long is a solar day?
24 hours
The cycle of the moon is how many days long?
29.5
An axis tilt of ___ would give basically no seasons at all.
3.1 (Jupiter)
One meter equals how many feet?
3.28 feet
How many seconds are in one hour?
3600
closest to the sun; Jan
Perihelion
Star cluster; not a constellation; near Taurus
Pleiades
The earth's axis always points toward
Polaris
The Big Dipper points you to
Polaris (the North Star)
The solar system model based on Greek ideals; Earth is at the center and does not move; everything in the sky goes around the sun
Ptolemy's Model
World's best naked eye astronomer; made extremely accurate observations without a telescope; used SN 1572 to show that the heavens change
Tycho Brahe
One evening at midnight, you observe Leo high in the southern sky. Virgo is to the east and Cancer is to the west. One month from now which constellation will be high in the sky at midnight?
Virgo
Why does the moon go through phases?
We see only part of the illuminated face of the moon depending on it position relative to Earth and the sun
Stellar parallax occurs because
We view nearby stars from different positions in Earth's orbit at different times of year
The constellations include how many rectangular regions in the sky?
88
One light year equals
9.46x10^12 (trillion) km 63,000 AU
One AU equals?
93 million miles 150 million km 8.3 light minutes
An axis tilt of _____ would give extreme seasons.
97.9 (Uranus)
farthest from the sun; July 5
Aphelion
The average distance between the sun and the earth
Astronomical Unit
The date of the winter solstice is
December 21
When we see Saturn going through a period of apparent retrograde motion, it means
Earth is passing Saturn in its orbit, with both planets on the same side of the Sun
What effect does mass have on something orbiting the sun?
It ain't got none
Created a theoretical model to explain planetary motion
Johannes Kepler
The date of the summer solstice is
June 21
The date of the vernal/spring equinox is
March 21
What are the names of the planets?
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
We live in the
Milkyway Galaxy
Are all eclipses equal?
NOOOOOOOOOOOOO
Developed details of a heliocentric model in which Earth and other planets orbit the sun
Nicolaus Coperincus
Are all of the stars in a constellation physically connected?
No
Ptolemy's model treated each planet independently; no single law governing the motion of all planets; this problem is know as
Occam's Razor
The date of the autumnal equinox is
September 21
brightest star in the sky
Sirius
What is the place that experiences the smallest amount of variation in the amount of sunlight over a year?
The Equator
A sidereal day is how long it takes for
a star to return to the same place in the sky
You walk outside at sunset and see the moon on your meridian. What is the phase of the moon?
first quarter
Stars that appear to move in a circle around either the North or South pole without rising or setting
circumpolar stars
Arrangement of stars
constellations
During the day, stars
continue moving just as they were at night
Earth spins ________ and revolves around the sun ________
counterclockwise, counterclockwise
Kepler's Third Law states that the square of the orbital period of a planet is directly proportional to the ... of its orbit
cube of the semi-major axis
There are different seasons in
different locations
In general, the stars, planets, the sun, and the moon rise in the _____ and set in the _____
east, west
An astronomical event that occurs when one celestial body is temporarily obscured by either another object or that object's shadow
eclipse
Kepler's First Law states that the orbit of every planet is an ______; with the ______ at one of the two foci.
ellipse, Sun
Kepler's Second Law states that a line joining a planet and the Sun sweeps out
equal areas during equal intervals of time
During the waxing crescent phase, how much of the moon's surface is illuminated?
exactly half
How much of the moon's surface is illuminated at any time?
exactly half
According to Kepler's second law, a planet with an orbit would
experience very little change in orbital speed over the course of a year
Where is the sun during the summer?
high in the sky; more hours of direct sunlight
As you move from the equator toward either pole the number of circumpolar stars
increases
The largest planet is
jupiter
The apparent east-to-west motion of an object relative to the stationary background stars
retrograde motion
A sidereal day depends on
rotation
A solar day depends on
rotation and revolution
Over the course of one day, the sun, moon, planets, and stars all move because
the earth's rotation makes everything appear to move across the sky
Moonlight comes from
the sun
A solar day is how long it takes for
the sun to return to the same place in the sky
What affects seasons?
the tilt of the Earth's axis
An eclipse can be
two stars, a star and a planet, a planet and a moon, a moon and a star, etc.