Astr 111 Midterm
A star is 230 light years away. The light we see tonight from that star left it
230 years ago
The acceleration of gravity on Earth is approximately 10m/s2. If you drop a rock from a tall building about how fast will it be falling after 3 seconds?
30m/s
The scientist who first devised experimental tests to demonstrate the validity of the heliocentric model of the solar system was
Galileo
The "prime meridian" (where longitude equals zero)passes through:
Greenwich, England
The Earth is closest to the Sun in which month of the year?
January
1. Which of the following is NOT a terrestrial planet?
Jupiter
The planet closest to the Sun in the solar system is:
Mercury
The star that is currently closest to the North Celestial Pole is:
Polaris
Newton showed that to change the direction in which an object is moving, one needs to apply:
a force
The location of the Earth in the Milky Way Galaxy is
a little less than 30,000 LY from the center
A Hertz is
a unit of frequency
The time it takes for the Sun to return to the same place in our sky after the Earth has rotated once is called:
a year
Within a constellation, a smaller, recognizable pattern of stars is often called:
an asterism
How fast do electro-magnetic waves travel?
at the speed of light
Why is there a 4-minute difference between the solar day and the sidereal day?
because the Earth is going around the Sun in the course of a year
The minimum speed required to launch an object so that it remains the same distance above the ground and just falls around the Earth is called:
circular satellite velocity
The way scientists know that a hypothesis in astronomy is a reasonable description of nature is to
do experiments and observations about the predictions of the hypothesis
In Newton's Law of Gravity, the force of gravity goes up as the: a. mass goes down b. distance goes up c. mass goes up d. distance goes down e. more than one of the above
e. more than one of the above
On which planet (besides the Earth) do we still see a high level of geological activity on the surface today? a. Jupiter b. Mercury c. Neptune d. Venus e. none of the above
e. none of the above
During the process of differentiation,
heavier materials sink to the centers of molten planets
Typically, astronomers express the right ascension of a star on the sky in what units?
hours, minutes, and seconds
The idea that objects (in the absence of an outside force) tend to continue doing what they are already doing is called the law of
inertia
The inner planets are made mostly of rock and metal because:
it was so hot where the inner planets formed that the lighter materials evaporated
Which of the following ways that jovian (giant) planets differ from the terrestrial planets is NOT CORRECT?
jovians have more mass than the terrestrials
The number of degrees of the arc that your location is north or south of the Earth's equator is called your
latitude
In the Northern Hemisphere, the altitude (height in degrees above the horizon) of the North Star is always roughly equal to the
latitude of the observer
What phase of the Moon must it be to have a solar eclipse?
new moon
The rate at which a collection of the same radioactive atoms will decay depends on:
only on internal processes within the atoms; nothing external matters
When a comet like Comet Hale-Bopp comes closest to the Sun in its orbit, we say that it is at:
perihelion
The material that would eventually make all the major bodies in our solar system first gathered together as smaller pieces which astronomers call:
planetesimals
When the Sun and Moon are lined up and pull together, the tides they raise are called:
spring tides
Why do astronauts (and cans of soft drink) float around in the Shuttle instead of falling?
the Shuttle is falling around the Earth (and everything aboard is in free fall)
Why does the Moon show phases in the course of a month?
the angle the Moon makes with the Sun changes and we see differing amounts of reflected sunlight
The Astronomical Unit (AU) as defined by astronomers is
the average distance between the Earth and the Sun
The Sun's apparent path around the celestial sphere is called
the ecliptic
What would you have to change about the Earth to stop our planet from having significantly different seasons?
the tilt of its axis
The light which allows you to see this very interesting exam is made up of waves. In these waves, the distance between crests is called the:
wavelength
A single star in the process of forming starts by spinning slowly (while it is quite large and relatively cool.) As the star collapses under the pull of its own gravity, its size decreases. As a result, its rate of spinning:
will increase
The point in the sky directly above your head at any given time is called the
zenith
From horizon to opposite horizon, the sky takes up how much angular distance?
180 degrees