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105 Cards in this Set

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  • Back
During its full phase, the Moon sets at approximately:
6 AM.
For astronauts living on the Moon, the time between sunrises is:
29.5 days.
The Declination of the Sun is 0 degrees:
On the Vernal and Autumnal Equinox.
1/60th of a degree is equal to:
an arcminute.
The point in the sky directly above the observer is called:
the zenith.
An annular eclipse is
when the moon's angular size is not big enough to cover the full face of the Sun.
In astronomy, the term `ecliptic' means
The path that the Sun takes across the sky.
Why is the solar day longer than a sidereal day?
Because Earth revolves around the sun.
A Full Moon crosses the Celestial Meridian at
A sidereal day is:
23 hours 56 minutes.
The precession (`wobbling') of the Earth causes the stars to slowly shift their positions relative to the Celestial Coordinate system. The Celestial North Pole traces a circle on the sky, moving from near Polaris, traveling past Deneb and Vega, and then back to Polaris. This precession has a period of:
26,000 years.
Mars is at opposition:
Every 780 days.
Solar eclipses occur:
only during new moon.
Partial or total solar eclipses happen approximately
Every six months
The distance from the Earth to the Sun is:
1 A.U. or 93 million miles
During which phase of the Moon is the Moon on the meridian at 6 AM?
Third quarter.
What planet has the fastest speed in its orbit around the Sun, in km/s?
Pluto is moving fastest in its orbit:
when it is closest to the Sun.
Ptolemy is best known for:
His book entitled `The Almagest'.
What planet goes though phases, like the Moon, as seen from Earth?
If a comet orbiting the Sun has a sidereal period of 8 years, what would be the semi-major axis of its orbit?
4 A.U
The large ancient `circle and spokes' made up of stones in northern Wyoming, thought to have astronomical and/or religious significance, is called:
The Big Horn Medicine Wheel.
What is one way to measure the relative size of the Earth and the Moon, without using advanced technology?
Time a lunar eclipse
The Sun is 3500 times more massive than Saturn. Therefore, the gravitational force that Saturn exerts on the Sun is:
the same as the force that the Sun exerts on Saturn.
In Kepler's Third Law, P2 = a3, the `a' stands for:
the semi-major axis of the orbit.
Who was Tycho Brahe's assistant?
Supported the geocentric model of the Universe.
Galileo was the first person to observe:
The phases of Venus
Assume your mass is 60 kg on the surface of the Earth. If you were freely floating in space far from a planet or moon, your mass would be:
60 kg
Newton's Second Law of Motion, in mathematical form, states:
F = MA.
What scientist first measured the relative size of the Sun and Earth?
If the distance between the Earth and the Moon decreased by a factor of 3, how would the gravitational force between them change?
It would increase by a factor of 9.
An epicycle is:
a `circle within a circle', used to explain the retrograde motion of the planets in the geocentric model of the Universe.
Microwaves are:
radio waves.
What property of an astronaut remains constant, whether they are on the Earth, on the Moon, or in orbit around the Earth?
A low density cloud of gas (such as a HII region) produces:
an emission-line spectrum.
The speed of light is:
a constant for all wavelengths in a vacuum, but it slows down in glass, air, or water.
Star A has a surface temperature two times larger than that of Star B. Therefore, the wavelength of the peak of the spectrum of Star A is:
1/2 that of Star B.
Atom A has 2 protons, 2 electrons, and 2 neutrons. Atom B has 2 protons, 2 electrons, and 1 neutron. Therefore:
Atom A has a mass approximately 4/3 times larger than Atom B.
Kirchoff's Laws describe:
what situation produces which kind of spectrum.
A star like the Sun produces:
An absorption-line spectrum.
In what kind of telescope is the detector (and sometimes the Astronomer) placed in front of the primary mirror, blocking some of the incoming light?
A Prime Focus telescope.
An ion is:
An atom which has lost an electron.
Bob has a mass of M1, and Pete has a mass of M2. Bob's distance from the center of mass of the Bob/Pete system is X1, while Pete's distance from the center of mass is X2. The equation that relates these four quantities is:
M1X1 = M2X2.
The change in the observed wavelength of light due to the relative motion of the observer and the source of light is called:
Doppler shift.
A watt is:
a joule/sec.
As a planet orbits around a star in an elliptical orbit, which of the following remains a constant?
the total energy.
From laboratory measurements, we know that the H-beta spectral line of hydrogen appears at a wavelength of 486 nm. The spectrum of a particular star shows this line appearing at a wavelength of 485 nm. What can we conclude?
The star is moving towards us.
An ordinary light bulb produces which kind of spectrum?
A continuous spectrum.
A Hertz is:
a cycle/sec (wavelength/sec).
The thermal spectrum of a human being peaks in the:
Are likely left-over planetesimals.
What type of light travels easily through our atmosphere, so ground-based astronomy is possible at these wavelengths?
Visible and radio.
What are extrasolar planets?
Planets orbiting other stars besides the Sun.
Which planet orbits the Sun in a direction opposite that of the rest of the planets?
How many moons are larger than Mercury?
Which objects have densities between 4 and 5.5 g/cm3?
The terrestrial planets.
The planet Mercury has been visited by:
Just Mariner 10.
Spirit and Opportunity are:
Rovers on Mars
The atmosphere of Jupiter is mostly:
Hydrogen and helium.
The atmospheric pressure on Venus is:
about 90 times that on Earth.
N2 is the most common molecule in the atmosphere of:
Compared to the 100 meter Green Bank radio telescope, the Arecibo 300 meter radio telescope has a light gathering power:
nine times larger
What moon was probably not formed with its planet, but formed elsewhere and gravitationally captured?
The Oort cloud is:
a vast reservoir of comet nuclei orbiting the Sun at a distance of about 1 light year.
According to the August 2006 definitions voted on by the IAU, the difference between a `planet' and a `dwarf planet' is:
A dwarf planet does not clear the neighborhood around its orbit.
Titan is:
the moon with the thickest atmosphere
How many moons does Mars have?
The extrasolar planets discovered to date are:
more massive than the Earth.
It is presently possible to measure the diameter of an extrasolar planet in a few special cases. How is this done?
timing it as it transits (eclipses) its star.
The CO2, H2O, and CH4 in our atmosphere are:
the molecules mainly responsible for absorbing IR from the Sun and Earth.
What is the evidence that the upper part of the mantle of the Earth is not completely liquid?
Both P and S waves travel through it.
X-rays from the Sun are mainly absorbed in which layer of the Earth's atmosphere?
Infrared light from the Sun and the Earth are mainly absorbed in which layer of the Earth's atmosphere?
The unstable isotope uranium-235 will spontaneously decay to lead-207, with a half-life of 700 million years. This means that in a time of 1.4 billion years:
3/4ths of the original uranium-235 will have decayed
What is the evidence that the outer core of the Earth is liquid?
Only P waves travel through it.
Most of the solar wind:
is deflected and trapped by the Earth's magnetic field lines.
The magnetic field of the Earth is caused by:
A magnetic dynamo caused by the motion of charged particles in the liquid outer core.
Regions where two continental plates are colliding, and one gets pulled under the surface, are called:
Subduction zones.
The reason the core of the Earth is very iron-rich is:
differentiation in the young molten Earth.
The rocks on the floor of the Atlantic Ocean:
increase in age with increasing distance from the Mid-Atlantic Ridge.
The magnetic field of the Earth is the primary protection for life on Earth from:
charged particles from the Sun.
The atmosphere of Mercury is mainly due to:
bombardment of its surface by the solar wind.
The Coriolis Force (Coriolis Effect) is:
a consequence of Newton's Laws applied to a rotating frame of reference.
With a small telescope, `stripes' are visible on Jupiter. These are due to:
circulation patterns in the atmosphere caused by convection, the rotation of the planet, and the Coriolis effect.
The Van Allen Belts are:
the magnetic field lines of Earth, where solar wind particles are trapped.
The deep sea trench off the western coast of South America is an example of:
a subduction zone.
Shepherd moons are moons that:
orbit near a ring, keeping the ring sharp and narrow.
Which of the following moons has the most impact craters?
Neptune looks blue because:
Its atmosphere contains some CH4.
The rovers currently operating on the surface of Mars:
Use stereovision to estimate distances.
The maria on the Moon were formed by:
impacts with planetesimals, which cracked the surface and caused lava to flow.
The name of the large, long-lived storm in the atmosphere of Jupiter that was seen by both Galileo the scientist and Galileo the spacecraft is:
the Great Red Spot.
The interior of Saturn is:
mostly liquid hydrogen, some in a `metallic' state, and a rocky core.
The maria on the Moon are:
large-scale lava flows from asteroid impacts breaking the crust.
The Magellan spacecraft found the following features on the surface of Venus:
large (probably) extinct volcanos and large-scale hardened lava flows.
Which of the following statements about Neptune are true?
It has a larger abundance of methane in its atmosphere than Jupiter.
Saturn is mostly made of:
hydrogen and helium.
The channels called `rilles' seen on the surface of the Moon were caused by:
past streams of molten lava.
What is the most obvious difference between the near side and the far side of the Moon?
The far side has more craters than the near side.
Where is Caloris Basin?
The Messenger spacecraft:
Is on its way to Mercury now.
What causes the gap in the rings of Saturn known as the Cassini Division?
The gravitational effect of Mimas.
Which moon is sometimes called the `pizza pie moon', since it is covered with large-scale lava flows, active volcanos, and sulfur dioxide frost?
The largest mountain in the solar system is:
Olympus Mons.