Astronomy Test #2
Impact craters are smaller in diameter on Earth than on the moon because the ___ moon has weaker gravity moon has no air Earth's crust is more rigid moon protects Earth from the largest meteoroids and asteroids moon is older than Earth
- moon has no air
The exact precession of Mercury's perihelion location was finally explained by ___.
- relativity theory
A visible photon passes very close to a hydrogen atom but is not absorbed. This could be because ___. the atom is ionized the photon moves too fast the photon moves in the wrong direction the atom's inner orbit is filled the atom is too low in energy
- the atom is ionized
We can usually measure the rotation velocity of a star from ___. - the width of spectral lines - a pattern of spectral line locations - the brightest part of its background spectrum - the difference between its apparent and absolute magnitudes - We have no way of measuring rotation velocity.
- the width of spectral lines
Star A has apparent magnitude 3, and star B has 13. A appears ____ as bright as B. 1/2.512 1/100 100 times 1/1,000 10,000 times
10,000 times
The curvature of spacetime was first observed in ____. 1897 1915 1919 1930 2002
1919
Uranus is closest to ___ times further from the sun than Saturn is 1.6 3.5 2 4 8.00
2
A star is seen to dim by 4% every time an exoplanet passes in front of it. The diameter of the planet is closest to ___ % the star's diameter 1.5 4 20 2 0.4
20
An Earthlike exoplanet orbits the star named Kepler 1649, which has a geometric parallax of 1/100 arcsecond. The light that exoplanet is now receiving from us was emitted ___ years ago 1/24 200 300 24 1200
300
On the average, the time between a low tide and the next high tide is ___. 6 hrs 12 mins 6 hrs 0 min 12 hrs 25 mins 12 hrs 0 min 12 hrs 49 minutes
6 hrs 12 mins
It cannot rain on Mars because of its low ___ altitude clouds atmospheric pressure mountains temperature wind velocities
Atmospheric Pressure
The rotation period of Venus is phase-locked ("spin-orbit coupled") to ___.
Earth
A hot gas of hydrogen atoms glows mostly because ___. the atoms are constantly accelerating electrons are being pumped to outer orbits by collisions the air between the H atoms is catching fire molecular binding energies are being absorbed the atoms are all totally ionized
Electrons are being pumped to outer orbits by collisions
The speed of light you measure from a rapidly approaching star is ___ compared to the light from a flashlight you hold in your hand. less by the star's velocity exactly the same more by the star's velocity the same for speed but not direction It depends on many more factors.
Exactly the Same
The surface of Europa is made primarily of ___. rock CO2 ice H2O ice sand liquid water
H20 Ice
The number of sunspots each month should theoretically be ___ this spring. increasing decreasing staying about constant about the same as last fall the highest we've ever seen
Increasing
The first evidence of ancient liquid water on Mars came from ___. spectrographs Voyager 1 Mariner 9 radio telescopes a Soviet flyby
Mariner 9
We first saw active rivers on titan in photos taken by ___. Cassini the Huygens probe Voyager II Voyager I We have not seen rivers on Titan.
The Huygens Probe
The Valles Marineris is about the length of ____. a football field the Grand Canyon California the United States We don't know.
The United States
The velocity of sound in water will always be the same when measured from the frame of reference of the ___. sound source listener ground water ether
Water
Reversing time should make a proton look like ____. an anti-proton a proton an electron it's disappeared it has negative mass
an anti-proton
Lunar rilles are now thought to be caused by ______. - ancient lava flows - ancient water rivers - recent lava flows - recent water rivers - ancient flows of neither water nor lava
ancient lava flows
The spectral lines from a star yield direct information about the star's ____. mass interior density photosphere composition diameter chromosphere composition
chromosphere composition
The Murchison meteorite gives us evidence of(that) ___. previous oceans on Mars tiny meteoroids can't penetrate our atmosphere iron decay extraterrestrial amino acids not all meteorites contain water
extraterrestrial amino acids
The Murchison meteorite gives us evidence of(that) ____. salty oceans on Mars tiny meteoroids can't penetrate our atmosphere nuclear iron decay extraterrestrial amino acids not all meteorites contain water
extraterrestrial amino acids
Philae stopped sending data soon after landing because it(s) ____ sank into the surface was supposed to stop sending data never did land got too cold harpoons failed
harpoons failed
Direct evidence for ancient life on Mars may possibly have been found ____. from orbital photos by the Phoenix lander in a meteorite on Earth on the Moon by the Spirit rover
in a meteorite on Earth
The number of sunspots each month should theoretically be ____ this spring. increasing decreasing staying about constant about the same as last fall the lowest we've ever seen
increasing
The "Blueberry Rocks" provide clear evidence of past Martian ___. liquid water CO2 ice life volcanism plate tectonics
liquid water
As you watch your friend fall head-first toward a black hole, he appears to ____. live slower get lighter get fatter get bluer not change at all
live slower
Michelson and Morley rotated their interferometer to ___. correct for air currents correct for Earth's magnetism make the interference pattern move keep it balanced They did not rotate it.
make the interference pattern move
The slit in a spectrograph is intended to ___. - make the spectral lines brighter - reduce the number of spectral lines - make the spectral lines sharper - filter out certain colors - calibrate the spectrum wavelength scale
make the spectral lines sharper
The dimensions of space and time are curved by ____. your velocity light massive objects temperature changes magnetic field
massive objects
We cannot use the Doppler method to detect an exoplanet if ___ it is too large it is too dark our line of sight is along its orbital axis the parent star is too bright its orbital plane it nearly parallel to Earth's
our line of sight is along its orbital axis
Mercury faces the same side to the sun when it is at its perihelion every ___. Mercury year second Mercury year 2.3 Mercury years second Earth year The same side always faces the sun.
second Mercury year
Because of relativity, you will see a man speeding past you living slower than you. He sees you living ___ than(as) him. faster slower at the same rate slower on approach and then faster This is an unsolved problem in relativity
slower
Two electrons are allowed in each atomic orbit in the Bohr atom model, in spite of the Exclusion Principle, because they ___. orbit in opposite directions have different masses have different sizes spin in opposite directions Only one is in fact allowed in each orbit.
spin in opposite directions
Io's interior stays warm because of ___. tidal forces sunlight Jupiter's radiation its atmosphere its dark surface
tidal forces