MidTerm Answers Flashcards
The greatest triumph of Newton’s theory of gravity was
Its ability to mathematically predict all 3 of Kepler’s laws
Which sentence best describes how Rømer first measured the speed of light?
He predicted when Jupiter’s moons would be behind the planet, and compared to observed time ½yr apart.
A scientific theory can be shown to be wrong if:
scientists gather new data that contradicts its predictions.
When an electron moves from a higher energy level in an atom to a lower energy level:
a photon is emitted
Light from the Moon takes about how long to reach Earth?
1 second
What are good reasons to put an telescope in Earth’s orbit?
to observe at wavelengths blocked by Earth’s atmosphere; to avoid light pollution; to avoid weather; to avoid atmospheric distortion
The ancients observed and recorded the motions of the Sun, Moon and Planets in the sky primarily for:
Religion, keeping time, charting seasons
The visible light spectrum from the Sun shows which of the following features?
Absorption lines and Continuum
EM radiation in order of decreasing wavelength (largest to smallest)?
Radio waves, infrared, visible, ultraviolet, X-rays.
Which principle does a telescope with lenses make use of to create a focus point?
Refraction
Which one of Galileo’s observations directly refuted the Ptolemaic mode of the Universe?
the phases of Venus
How did Kepler fix the “Great Martian catastrophe”?
By correctly positioning the Earth’s orbit relative to the Sun in Copernicus’ heliocentric model of the universe.
For northern latitudes, the day that the Sun is seen lowest in the southern half of the sky marks the
winter solstice
During the formation of a planetary system why does a spinning cloud begin to spin faster as it collapses?
The cloud rotates faster to conserve the angular momentum it had when it was larger & spinning slower.
If the moon is new and is on the ecliptic, what would we see from Earth?
A total or annular Solar eclipse.
Earth doesn’t experience an eclipse of the Sun every month because
the moon’s orbit is not in the same plane as the Earth’s orbit.
Which condition below is true for a total Solar eclipse?
The Moon must be new and on the ecliptic.
If you are lucky enough to see a total solar eclipse, you must be standing in the:
Moon’s umbra.
Which best describes where in the sky the Sun (and hence the ecliptic) is during the
spring equinox?
The Sun (and the ecliptic) is 0 away from the equator.
Why are the seasons on Mars so similar to those on Earth?
Mars rotation axis is tilted with respect to its orbital plane by the same amount as Earth’s.
Like Mars and Venus, Earth originally had a lot of carbon dioxide in its atmosphere. Where is the majority of the carbon now?
It is bound up in rocks.
Mars, Venus and the Earth are much less heavily cratered than Mercury or the Moon. This is explained by the fact that:
Mars, Venus and Earth were geologically active for a longer period of time than Mercury or the Moon.
When was the most recent (i.e. youngest) crater on the moon’s surface made?
Today!
At what point in its appearance in the sky is Mars furthest from the Earth?
Conjunction
