74 terms

Honors Astronomy Exam 1

When we observe a galaxy 10 LY away,
we see it as it was a billion years ago
Ages of stars are
NOT "millions of light years"
A wavelength of 10 microns is
in the infrared part of the spectrum
By measuring the light intensity from a distant light bulb, you can calculate its distance if you know the bulb's
In astronomy we try to
catalog objects and determine their origin
A hypothesis that passes initial testing
is ranked as a theory
An emission line with a wavelength of 6563 angstroms is
The most energetic photon is
According to the Stephen-Boltzmann Law, if the sun were twice as hot as it is,
it would be 16 times more luminous
The sun has
a absorption-line spectrum
In a hydrogen atom,
the proton has the most mass
A star with a surface temp of 10^4 K would be
bluer than the sun
A line in the Balmer series of hydrogen is
Red shifts in wavelength are produced by
The surface temp of the sun is about
5800 K
The light-gathering power of a telescope is proportional to its
Both Newtonian and Cassegrain telescopes
use 2 mirrors
Interferometers have
better angular resolution than ordinary telescopes
Spectrometers have
If the sin is setting and the moon is rising,
the moon is in the full phase
To see a total solar eclipse, you must be in the
How long a star is above the horizon depends on its
Precession takes about
26000 years
Some stars have
negative apparent magnitudes
The declination of Polaris is about
90 degrees
Fayetteville is at a latitude of about
36 degrees
In Grenwich, England, it is
later in the day now than it is in Fayetteville
The ecliptic is a projection of
the Earth's orbital plane
In Fayetteville at noon, the sun is farthest south in the
Planets usually move
west-to-east relative to the fixed stars
In Ptolemy's model
the planets orbited the Earth
Can stellar parallax be measured these days?
yes, but hey are less than an arc second
The moons of Jupiter were discovered by
The F=ma law was discovered by
Unlike Kepler's 3rd law, Newton's result contained
The plane of the orbits of the planets is a remnant of
the spin of the gas and dust cloud that spawned them
When we observe an object 10 billion light years away, we see it
as it was in the past
A photon of wavelength 5500 Å is in
the visible part of the spectrum.
My body emits mainly
infrared radiation
Blue photons carry
more energy than red photons
Wavelengths observed by ground-based telescopes are
limited by the atmosphere
The sun has
its peak wavelength in the visible
A light bulb radiates
a continuous spectrum
In the Bohr model downward transitions produce
emission lines
The Doppler effect measures
the radial component of the velocity
The boiling point of water in K is
In a telescope, the objective
gathers the light
The resolution of ground-based telescopes is limited to about 2 arcsec because
the "seeing" effects
A spectrogram may be displayed in the form of a graph of
intensity and wavelength
Lunar eclipses only happen when the moon is
Lunar eclipses can only happen during
during eclipse season
From the Earth's equator, the North Celestial Pole is
on the Northern horizon
The Sun appears to move
along ecliptic
Suring summer in Fay, the Sun is
farthest north of the celestial equator
Epicycles were invented to
explain retrograde motion
The major planets all show
prograde revolution
His model used epicycles
In Copernicus' model, retrograde motion was due to
motion of the observer
In Kepler's model,
the Sun is at one focus of the elliptical orbit
Kepler's 2nd law is known as
the "equal areas" law
An astronomical unit is
the distance of the Earth to the Sun
When we observe the stars near the Sun, we see them as they were
years ago
If we know the ___ of an object, we can calculate its distance from its apparent brightness.
energy output
Light waves longer than infrared are in the ___ part of the spectrum.
If you know the size and angular diameter of an object, you can calculate its
Black bodies radiate a(n) ___ spectrum.
Upward transitions in the atom's electron orbits produce
absorption lines
The bigger the blue shift is, the
faster the approach is
The largest telescopes are
reflecting telescopes
A spectrometer contains
a collimator
Full moon rises at
The faintest stars visible to naked eye are
magnitude of 6
In Ptolemy's model,
Earth was not on the epicycle
The line connecting the Sun to the planet is called
radius vector