Intro to Astronomy Midterm (1-7, 12)
The latitude of the Earth's equator is
0˚
An astronomy textbook, when printed out, weighs four pounds on the surface of the Earth. After finishing your course, you are so tired of the book, you arrange for NASA to shoot it into space. When it is twice as far from the center of the Earth than when you were reading it, what would it weigh? (Note, assume that the book has been moving away from the Earth, not falling freely around it.)
1 lb (less gravity so it's lighter)
Which ancient Greek thinker suggested (long before Copernicus) that the Earth is moving around the Sun?
Aristarchus
Which of the following is NOT one of the largest moons in the Solar System?
Atlas (the shepherd moon near Saturn's A ring)
Pluto's big satellite is called
Charon
Pluto was discovered through the patient searching of
Clyde Tombaugh
The first x-ray telescope capable of forming images from x-ray sources was called:
Einstein
The satellite whose surface is characterized by a smooth icy crust with a complex network of cracks is:
Europa
The scientist who first devised experimental tests to demonstrate the validity of the heliocentric model of the solar system was
Galileo
The Galileo spacecraft measured that the moon Ganymede had a magnetic field, indicating that its interior was at least partly melted and warm. What do scientists think is the most likely reason for this?
Ganymede is heated by tidal forces from Jupiter
The scientist who formulated the three laws of planetary motion by analyzing the data on the precise location of planets in the sky was:
Johannes Kepler
A planet in our solar system whose composition resembles that of our Sun is:
Jupiter
The first radio telescope was built in the 1930's by
Karl Jansky
The same astronomer wrote extensively about canals on Mars and about the possibility of a ninth planet in our solar system. The observatory named after this astronomer is the:
Lowell Observatory
The planet closest to the Sun in the solar system is:
Mercury
The planet in our solar system with the shortest period of revolution is:
Mercury
The moon Triton orbits which of the planets?
Neptune
The idea that atoms radiate energy only when their electrons move from higher to lower energy levels was first advanced by:
Niels Bohr
At which of the following locations on Earth is the direction we call East not clearly defined?
North Pole
Two worlds in the outer solar system that seem remarkably similar to each other are:
Pluto and Triton
The star that is currently closest to the North Celestial Pole is:
Polaris
The first artificial satellite the human race lofted into orbit was called:
Sputnik
On Earth, we can get the age of various parts of our planet by finding rocks that contain radioactive atoms. Which other world do have a good number of rocks from to do this kind of age analysis?
The Moon
Which of the following statements about Saturn's rings is TRUE?
The rings are made of billions and billions of individual "moonlets" (small chunks)
After a long night of cramming for a test, your college room-mate hits his head forcefully against the wall of your room in despair. According to Newton's 3rd Law, as he exerts a force against the wall, there must be an equal and opposite force. How does that opposite force show itself in this case?
The wall exerts a force on your room-mate's head and he has a headache
The 17th century astronomer who kept a roughly 20 year continuous record of the positions of the Sun, Moon, and planets was:
Tycho Brahe
What specific event really made it possible for the three laws of planetary motion to be discovered?
Tycho Brahe died and his assistant was able to get full access to his data
The rings that most resemble Saturn's narrow F ring in the solar system are:
Uranus' rings
On which planet (besides the Earth) do we still see a high level of geological activity on the surface today?
Venus
Which of the following statements about the International Date Line is correct?
When crossing from west to east, you must decrease the date by one day
The largest refracting telescope in the world, financed by a Chicago millionaire in the 1890's, is at the:
Yerkes Observatory
Newton showed that to change the direction in which an object is moving, one needs to apply:
a force
In a radio telescope, the role that the mirror plays in visible-light telescopes is played by:
a large metal dish (antenna)
When two objects in orbit have periods of revolution that are simple ratios of each other (such as 1 to 2 or 1 to 3) we say that we have:
a resonance
This chapter discusses that light sometimes acts like a photon. What is a photon?
a self-contained "packet" of electro-magnetic energy
From a particular location on Earth, why can we see many more total eclipses of the Moon than total eclipses of the Sun?
a total lunar eclipse is visible over a much larger part of the Earth's surface than a total solar eclipse
The natural object (not one that humans built) in space that's closest to Earth is a) The Moon b) Mars c) Alpha Centauri d) Jupiter e) The Sun
a) The Moon
Which of the following is NOT an advantage that a reflector telescope has over a refractor telescope? a) a reflector doesn't have to deal with the twinkling of the stars, as a refractor does b) the device that collects the light is more easily supported in a reflector c) reflectors can be built with much bigger apertures d) reflectors avoid the problem of chromatic aberration in the lens e) flaws and bubbles in the material inside a thick mirror are not a problem, while flaws and bubbles in the material inside a thick lens are
a) a reflector doesn't have to deal with the twinkling of the stars, as a refractor does
The smallest piece of an element (like gold or lead) that still has all the properties of that element is called a) an atom b) an electron c) ytterbium d) a neutron e) a quasar
a) an atom
Which of the following major telescopes was NOT located in space? a) the Keck Telescope b) the International Ultraviolet Explorer c) the Compton Gamma-ray Observatory d) the Hubble Space Telescope e) the Roentgensatellit (ROSAT) x-ray telescope
a) the Keck Telescope
Of the following, which consists of electro-magnetic waves with the shortest wavelength? a) the waves of a dental x-ray b) the sound of the instructor's voice c) a beam of green light d) the rays that tan a sunbather on the beach e) TV transmissions bringing us Monday night football
a) the waves of a dental x-ray
Radioactive dating techniques have revealed that our Earth and Moon are approximately how old?
about 4.5 billion years
A friend of yours (who has not had the benefit of an astronomy course) tells you about a report he has read in a tabloid newspaper. They claim that on the dark side of the Moon, which is never in sunlight, there is a secret base of aliens who cannot stand light, and who send UFO's to Earth under the cover of darkness. Ignoring the UFO claim for a moment, what is the scientific error in this story?
all sides of the Moon are illuminated by sunlight in the course of a month; there is no dark side
When chemists say that a planet's upper regions are reduced, they mean that these regions
are dominated by the element hydrogen and its compounds
Based on the scientific and statistical tests of astrological predictions, which of the following statements is the most reasonable?
astrology has not passed any clear scientific or statistical test and, as a result, most scientists are very doubtful that it can predict anything meaningful about our lives
If you could see the new moon, at what time of day (roughly) would it rise?
at sunrise
An eccentric billionaire wants to build a mansion in a location on Earth where the effect of the seasons is the least pronounced -- where summer and winter are not that different. Where should his personal astronomer advise him to build?
at the equator
Where on Earth do stars always circle the zenith (and never rise and set)?
at the north pole
How fast do electro-magnetic waves travel?
at the speed of light
Which of the following worlds does NOT have a ring? a) Neptune b) Pluto c) Jupiter d) Saturn e) Uranus
b) Pluto
Of the following planets, which do NOT have satellites (moons)? a) Earth b) Venus c) Mars d) Jupiter e) you can't fool me, all the planets have satellites
b) Venus
The location of the Earth in the Milky Way Galaxy is a) on the edge of the Galaxy as far from the center as you can measure b) a little less than 30,000 LY from the center c) in the center of the Galaxy d) this is a trick question: the Earth is not located in the Milky Way Galaxy e) something astronomers have not yet measured
b) a little less than 30,000 LY from the center
Which of the following statements about the force of gravity is FALSE? a) it is a universal force, which acts everywhere in space b) its strength is inversely proportional to the mass: the more mass, the less gravity c) it causes the paths of the planets to be ellipses and not straight lines d) its strength decreases as the square of the distance e) the force never becomes zero
b) its strength is inversely proportional to the mass: the more mass, the less gravity
The Astronomical Unit (AU) as defined by astronomers is a) the time it takes for the Earth to orbit the Sun once b) the average distance between the Earth and the Sun c) the distance the Earth travels in orbit in one day d) a distance of one light year e) the distance between Congress and the White House
b) the average distance between the Earth and the Sun
Which of the following statements about the nucleus of a typical atom (such as a carbon atom in your little finger) is FALSE: a) the nucleus has an overall positive charge b) the nucleus repels the electrons which move around it c) the nucleus contains most of the mass of the atom d) the nucleus contains both protons and neutrons e) the nucleus takes up a very small amount of space compared to the entire atom
b) the nucleus repels the electrons which move around it
Which of the following statements about forces is FALSE? a) forces always occur in equal and opposite pairs b) there are places on Earth where all forces are absent c) forces change the momentum of a body d) forces cause an acceleration to take place e) where there is no force, objects continue to move the way they were moving
b) there are places on Earth where all forces are absent
Why do telescopes have to have a good motorized drive system to move them quickly and smoothly?
because the Earth is rotating, with the telescope attached to it
When the authors of our textbook say that astronomers are like police detectives trying to solve crimes, they are explaining that: a) Both astronomers and detectives mostly work at night b) Both astronomers and detectives use expensive equipment c) Both astronomers and detectives must test their hypotheses against any evidence that they gather d) Both astronomers and detectives work for the government e) Both astronomers and detectives turn out to be wrong much of the time
c) Both astronomers and detectives must test their hypotheses against any evidence that they gather
Which of the following places is most likely NOT to be differentiated? a) Venus, because it is so hot b) Earth c) a small asteroid d) Jupiter e) Ganymede, the largest satellite in the solar system
c) a small asteroid
A large body in space that consistently makes its own light (instead of merely reflecting another body's light) is called a) a moon b) a satellite c) a star d) a planet e) a light year
c) a star
Even with the best and largest telescopes, we can't see all the stars in the Milky Way Galaxy, even though these same telescopes can show us other galaxies. Why is that? a) starlight isn't able to travel through black space b) the Milky Way Galaxy turns too quickly c) dust in the space between stars builds up over large distances and blocks the light of stars behind the dustier parts of the Milky Way d) the lights of Bayonne, New Jersey are too bright and interfere with our observations e) this is still an unsolved problem in astronomy
c) dust in the space between stars builds up over large distances and blocks the light of stars behind the dustier parts of the Milky Way
Every celestial object appears to go around the Earth once a day. In addition to this motion, which celestial object has the fastest apparent motion in the sky? a) Venus b) the Big Dipper c) the Moon d) Mars e) the Sun
c) the Moon
The star that provides energy for life on Earth is a) Beyonce b) the Moon c) the Sun d) Alpha Centauri e) the Milky Way star
c) the Sun
To come up with the precise mathematical form of his law of gravity, Newton first had to invent the mathematical techniques that we now call:
calculus
On the celestial sphere, halfway between the celestial poles lies the
celestial equator
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 most important function of an astronomical telescope is to:
collect as much light as possible and bring it to a focus
The smaller objects in the solar system composed mainly of ices (frozen gases) that usually orbit far from the Sun are called:
comets
What is one way that astronomers have actually gotten an idea of the age of the surfaces of terrestrial planets other than the Earth?
counting craters
A star is 230 light years away. The light we see tonight from that star left it a) one year ago b) 2.3 years ago c) 23 years ago d) 230 years ago e) the time depends on which part of the sky the star is in
d) 230 years ago
Light travels 3 x 10^5 kilometers every second. That number in words is: a) 30 kilometers b) 3,105 kilometers c) 310 kilometers d) 300,000 kilometers e) none of the above
d) 300,000 kilometers
Which of the following has a longer integration time (can collect light for a longer period of time) than the human eye? a) photographic film b) photographic plates c) a CCD (charge coupled device) d) all of the above e) none of the above
d) all of the above
Which of the following statements about Charon is FALSE? a) it takes the same amount of time to rotate and revolve b) it keeps the same face toward Pluto c) it takes the same time to go around Pluto as Pluto takes to rotate d) it has a significant atmosphere e) it has a retrograde orbit (revolves in a direction opposite to the sense that most satellites in the solar system revolve)
d) it has a significant atmosphere
Which of the following is NOT an advantage that the Hubble Space Telescope has over large telescopes on Earth? a) the Hubble is above the Earth's atmosphere, while on the ground star images twinkle and jiggle b) you can't fool me, all of these are advantages the Hubble has over earth-bound telescopes c) the Hubble has a better resolution than visible-light telescopes on Earth (not counting adaptive optics) d) the Hubble has a larger aperture than any visible-light telescope on Earth e) the Hubble can observe at wavelengths (such as UV) which cannot be seen from the ground
d) the Hubble has a larger aperture than any visible-light telescope on Earth
A light year is a) how long it takes a Friday afternoon class in college to get finished b) the time it takes light travel between the Sun and the furthest planet c) the distance between the Sun and the next star d) the distance that light travels in one year e) the time it takes a beam of light to go completely around the Earth's orbit
d) the distance that light travels in one year
All molecules (like molecules of water or carbon dioxide) are made up of a) baby animals that burrow underground b) very small pieces of dust, from the material that lies between the stars c) hydrogen d) two or more atoms e) groups of stars
d) two or more atoms
After a nice dinner around the campfire on a camping trip, you and a friend decide to get away from the fire to observe the stars. As you get farther and farther away, you see the brightness of the fire:
decrease as the distance squared
You are the captain of an interplanetary tour ship and a wealthy tourist from Texas asks you to take him to see only the "largest darn planets" in the solar system. Which of the following would you NOT include in your tour? a) Jupiter b) Uranus c) Neptune d) Saturn e) Mercury
e) Mercury
Of these which is the closest to us? a) the closest spiral galaxy b) the Sun c) Mars d) the center of the Milky Way e) The Moon
e) The Moon
Of these, which is the largest? a) The Milky Way Galaxy b) Jupiter c) Earth d) The Solar System e) The Universe
e) The Universe
Which of the following has the greatest density? a) a cubic meter of snow b) a cubic meter of astronomy textbooks (the printed versions, not the on-line ones) c) a cubic meter of air d) a cubic meter of feathers e) a cubic meter of lead
e) a cubic meter of lead
Which of the following is NOT a detector of radiation from space that astronomers have used? a) a photographic plate b) a charge-coupled device (CCD) c) eyes in the head of the astronomer d) a piece of photographic film e) a refracting telescope
e) a refracting telescope
Two stars are giving off electromagnetic radiation. The hotter star will: a) give off more radiation at all wavelengths b) will have a higher average frequency of radiation c) will radiate energy at more than one wavelength d) will give off a continuous spectrum of waves e) all of the above
e) all of the above
The way scientists know that a hypothesis in astronomy is a reasonable description of nature is to a) consult with the oldest experts in the field b) take a vote of astronomers around the world c) look it up in Wikipedia d) count how many scientific papers have been written about it e) do experiments and observations about the predictions of the hypothesis
e) do experiments and observations about the predictions of the hypothesis
Astronomers observe a typical star using a telescope and a spectrometer. They will see: a) a continuous spectrum b) an absorption spectrum c) an emission spectrum d) a Doppler shift e) more than one of the above
e) more than one of the above
The laws of nature (as determined by scientists) a) are constructed from many observations, hypotheses, and experiments b) apply both on Earth and among the stars c) can never, ever change once they are written down in textbooks d) are often written in the language of mathematics e) more than one of the above
e) more than one of the above
In the future, several students living on board a space station decide to have a race among different types of electromagnetic radiation. Which of the following travels through space the fastest? a) visible light b) radio waves c) infrared d) x-rays e) you can't fool me, all of these travel through space at the same speed
e) you can't fool me, all of these travel through space at the same speed
The Earth NOT located in which of the following? a) the solar system b) the Milky Way Galaxy c) the Local Group of galaxies d) The Virgo supercluster e) you can't fool me, we ARE located in all of the above
e) you can't fool me, we ARE located in all of the above
The fact that each type of atom has a unique pattern of electron orbits helps explain why
each type of atom shows different absorption or emission spectra
In the 19th century, it became clear that magnetism was not a separate force, but was always produced by the action of
electric charges that were in motion
By the term universe, astronomers mean
everything that we can observe
Which of the following was NOT done by Galileo Galilei?
explaining retrograde motion with the heliocentric hypothesis
Generally, planets and moons in our solar system are named after
gods and goddesses from mythology
When astronomers say that Ganymede is a differentiated body, they mean that it:
has a heavier core, surrounded by a lighter, icy mantle and crust
The energy of random atomic and molecular motion is called
heat
During the process of differentiation,
heavier materials sink to the centers of molten planets
When it comes to our place in the solar system today, which model do we accept?
heliocentric
Typically, astronomers express the right ascension of a star on the sky in what units?
hours, minutes, and seconds
In Australia (in the Southern Hemisphere), when are the days the shortest and the nights the longest?
in late June
You are on a camping trip, far away from city lights. You look up into the dark night sky, and see lots of stars, some brighter, some dimmer. All the stars you see with your unaided eye are
in the Milky Way Galaxy
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
When an atom has lost one or more electrons, it is said to be:
ionized
In studying the surfaces of solid bodies in the solar system, astronomers have learned that the number of craters (per unit area):
is roughly proportional to the age of the surface we are examining
In a bad late-night science fiction film, a villain is using a large collection of rare radioactive atoms as energy for a weapon to threaten the good guys. The atoms have a half-life of 1 hour. The villain has 4 kilograms of the radioactive material now, and he needs a minimum of 1 kg. for his weapon to work. After how much time will the weapon no longer be a threat?
just a little after 2 hrs
A friend of yours who takes her astronomy class very seriously challenges you to a contest to find the thinnest crescent moon you can find just after new moon? What time of day is best for looking for this very thin crescent?
just as the sun is setting, or just after
To figure out what you weigh on the surface of the Moon (how much gravity there pulls you downward), you need to know
just the size of the Moon's orbit around the Earth (its semi-major axis, say)
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
We have two waves of light, A and B. Wave A has a higher frequency than wave B. Then wave B must have:
longer wavelength
An astronomer discovers a new star and wants to measure its temperature. She would typically do this by:
making a blackbody curve and finding the wavelength of the peak (maximum)
The planet Neptune was discovered by means of:
mathematical calculations of how it was perturbing the motion of a neighbor planet
According to the geocentric view, everything in the heavens had to go around the Earth, which was the center of the universe. What objects did Galileo discover with his telescope that clearly didn't go around the Earth?
moons around the planet Jupiter
What phase of the Moon must it be to have a solar eclipse?
new moon
A very wealthy donor decides to give a large sum of money to your college or university to build the world's largest visible-light gathering telescope. From an astronomical perspective, where would be the best location to put such a telescope?
on a tall, dry mountain peak
A very rich, very shady international banker (with residences all over the globe, including Bayonne, New Jersey) mysteriously disappears. Someone later mails a wide-angle photo of his body to a London newspaper, taken on June 22, showing the Sun exactly overhead at noon. What can the police deduce from this photograph about where on Earth the body is located?
on the Tropic of Cancer (230 N)
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
Callisto, the fourth moon of Jupiter's, takes 17 days to orbit Jupiter. If I stand on the surface of Callisto and see Jupiter high in the sky over my head, and then wait 8.5 Earth days in the same spot, where will I see Jupiter?
overhead, where it was before
Today, the chemistry of the terrestrial planets does not include a lot of free hydrogen. Chemists call the chemistry in places like the Earth:
oxidized
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
The slow tipping of the Earth's axis in a circle with a period of about 26,000 years is called:
precession
A fashion designer decides to bring out a new line of clothing which reflects the longest wavelength of visible light. What color will these articles of clothing be to the human eye?
red
The earliest telescopes used by astronomers were:
refractors
If I stood on the surface of Pluto, observing its big moon, I would see that moon:
remain in the same place in the sky
When a planet temporarily moves westward in the sky over the course of several weeks or months (instead of eastward, as it typically does), we call it:
retrograde motion
All the planets (without exception)
revolve around the Sun in the same direction
A serial killer from a strange cult only kills his victims when the Moon is full. He leaves a note on the body of his latest victim, explaining that the murder was committed when the Moon was rising. What time of day did the murder take place?
roughly around sunset
The majority of the moons orbiting the outer (jovian) planets are:
small moons orbiting in a retrograde direction (opposite to the direction their planet turns and orbits)
The two regions of the electromagnetic spectrum where the Earth's atmosphere is transparent (radiation can get in) are visible light and:
some radio waves
An astronomer who is observing visible light from a glowing cloud of gas in space uses an instrument which contains a grating with thousands of grooves on its surface. What will this instrument allow our astronomer to do?
spread out the light from the cloud into a spectrum
When the Sun and Moon are lined up and pull together, the tides they raise are called:
spring tides
The Stefan-Boltzmann Law relates the energy flux coming from a blackbody (such as a star) to its:
temperature
The south celestial pole and the north celestial pole lie in the sky directly above
the Earth's axis
Why was the problem of devising a workable yearly calendar so difficult on Earth?
the Earth's rotation period does not divide evenly into the Earth's period of revolution
Our modern understanding of Pluto is that it is a member of
the Kuiper Belt (of trans-Neptunian objects)
Which of the following is NOT an argument for showing that the Earth must be round:
the Sun is seen blocking different constellations in the course of a year
Which of the following is an important part of the reason it is hotter in summer in North America than in winter?
the Sun's rays hit the Earth more directly in the Summer, and spread out less
Of the following, which has the highest resolution (ability to make out fine detail):
the Very Long Baseline Array of Radio Telescopes, stretching from the Virgin Islands to Hawaii
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
We observe a glowing cloud of gas in space with a spectroscope. We note that many of the familiar lines of hydrogen that we know on Earth seem to be in a different place. They are shifted toward the blue or violet end of the spectrum compared to their positions in the spectrum of glowing hydrogen gas on Earth. From this we can conclude that:
the cloud is moving toward us
In an ellipse, the ratio of the distance between the foci and the length of the major axis is called:
the eccentricity
The Sun's apparent path around the celestial sphere is called
the ecliptic
What is the cause of its many volcanic/geyser-like eruptions on the moon Io?
the gravitational stress of being so close to Jupiter and its other large moons heats Io's inside
If you could somehow return to the Earth in many millions of years, which of the following will be different?
the length of the month
The U.S. has plans to build a 30-meter telescope, while the Europeans are thinking about 39-meter telescope. What technological innovation allows astronomers to be thinking about telescopes with that large an aperture?
the mirror in these telescopes will be constructed from many smaller mirrors which will work together
For scientists, an element (like gold) is defined by
the number of protons in its nucleus
Most ultraviolet radiation does not penetrate to the Earth's surface. Instead it is absorbed in:
the ozone layer
The celestial sphere turns once around each day because
the planet on which we live is rotating
In Ptolemy's system the planets orbit the Earth and not the Sun. How did the system explain the retrograde motion of planets like Jupiter?
the planets moved on a small circle whose center, in turn, circled a point near the Earth
Consider a radio wave from the transmitter of your favorite radio station, which has just reached the antenna of the radio in your room. Which of the following statements about this radio wave is CORRECT?
the reason that it could reach your radio is because all of space is filled with a medium called the aether in which electromagnetic waves can vibrate
In the Greco-Roman tradition, the seven days of the week are named after:
the seven "wandering" objects in the Sky that were visible to the ancients
Which of the following is NOT a result of the Earth's precession?
the stars twinkle when seen from the surface of planet Earth
An astronomer is studying galaxies of stars that are very far away and thus look extremely faint (using visible light). What kind of telescope should she and her graduate students apply for time on?
the telescope with the biggest aperture possible
What makes the rings of Neptune different from those of other planets we know?
they are clumpy (or bulging) in pla
Why do satellites launched into low-Earth orbits not remain there indefinitely?
they lose speed due to friction with the upper layers of the Earth's atmosphere
When the twin Keck telescopes were built in the 1990's, what distinguished them from other very large telescopes of the time?
they used a mirror assembly that was made of 36 smaller hexagonal mirrors working together
You and some friends decide (during a wild party held at the time of the Full Moon) that you cannot live without having the secret recipe for the veggie burger they serve in the college cafeteria. So you decide to plan a break-in to steal the recipe from the chef's office. So that you don't get caught, you want to carry out your plan when there is no moonlight in the evening. What is the next phase of the Moon with no evening moonlight (i.e. when the Moon rises roughly at midnight or later)?
third quarter
Radio telescopes of modest size can't make out as much detail (have a lower resolution) than visible light telescopes. How do astronomers overcome this limitation?
we can connect several radio telescopes some distance apart together electronically to give us the resolution of a larger telescope
Astronomers discover a new comet that orbits the Sun, but has its aphelion (the furthest point in its orbit) beyond Neptune. Astronomers studying this comet have the right to expect that it:
will follow Newton's laws of motion
On which of the planets (other than Earth) could a human being step out of a spacecraft and survive without any protective gear (special suit, oxygen tanks, etc)?
you can't fool me; there is no other planet on which we could survive unprotected
The point in the sky directly above your head at any given time is called the
zenith
