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How do bipolar jets relate to lobe radio galaxies? Why was Voyager 2 an extremely efficient and productive probe? Answer: Using gravitational assists, Voyager 2 was able to visit all four jovian planets, making many discoveries along the way. In […]

The ________ Space Telescope still gives us the highest resolution optical images. Why is the light from near a black hole red shifted? Answer: The gravity is great enough to decrease the energy of the escaping photons and thus increase […]

What are two differences observed between Type I and Type II supernovae? The balance between gravity and ________ creates the internal structure of stars. Answer: radiation (pressure) Sagittarius A* was first noted due to its strong ________ emissions. Answer: radio […]

Mercury, Venus, and Earth have similar densities. The surface of Io looks most like the pack ice of the Arctic Ocean of Earth. Answer: FALSE In blackbody radiation, the energy is radiated uniformly in every region of the spectrum, so […]

A neutron star ________ rapidly. The distribution of stars in the Galactic Bulge reminds us of the distribution of objects in the solar system’s ________ Belt beyond Neptune. Answer: Kuiper The complete spectral classification of our Sun is ________. Answer: […]

All Type II supernovae produce neutron stars when they collapse. Our Sun will never become hot enough for carbon nuclei to fuse. Answer: TRUE Venus’ rotation period is longer than its period of revolution around the Sun. Answer: TRUE A […]

Generally, the densest parts of the interstellar medium are the ________. Weather always occurs in the lowest layer of the atmosphere, the ________. Answer: troposphere How does a star’s luminosity relate to its radius and surface temperature? Answer: As either […]

The nova event is created by the helium flash. Many astronomers now regard Pluto as just one of the largest of the thousands of Kuiper Belt bodies found beyond Neptune. Answer: TRUE The lunar mare are younger than any of […]

Differential rotation is when a planet’s equatorial and polar regions rotate at different rates. There is a superforce that separates into the electromagnetic, weak, and strong nuclear forces below a critical temperature. Answer: TRUE Stars do not twinkle; the instability […]

Why is the atmospheric pressure at the surface of Venus so much higher than Earth’s? A lens must be ________ in shape to focus the transmitted light. Answer: convex Why was the 1978 Nobel Prize in Physics given to Penzias […]

Pluto has only a single moon, Charon. Triton and Pluto both probably originated in the Kuiper Belt. Answer: TRUE Without the strong nuclear force, the universe would be made only of hydrogen. Answer: TRUE Methane drives the weather of Titan, […]

Supergiant stars are burning different fuels in several shells around the core. If the value of H has not changed since the Big Bang, then H = 70 km/s/Mpc will give a Hubble Time of about 14 billion years. Answer: […]

The time interval of 365.242 days is defined as the ________. All ________ planets have rings around their equators Answer: jovian The most important greenhouse effect gas in our atmosphere is ________. Answer: carbon dioxide The most abundant molecule in […]

The rotation curve of the outer portions of the Galaxy revealed what about its mass? Like latitude on Earth, ________ in the sky is measured in degrees north and south of the equator. Answer: declination Mass added to a pulsar […]

How can prolonged observations of pulsars yield their approximate age? The burst of X-rays from an X-ray burster is due to ________ of hydrogen on its surface. Answer: fusion How did Ptolemy explain the retrograde motion of Venus? Answer: The […]

The closed universe is compared to the surface of a ________ in spacetime. Explain how the central engine powers an active nucleus or quasar. Answer: Matter from an accretion disk spirals inward toward the event horizon of the supermassive black […]

The 3 K background radiation is just the redshifted gamma wavelength radiation of the decoupling. All optical telescopes will bring the light from a star to a focus. Answer: TRUE As an artificial radio source, the spinning Earth would have […]

Describe the large-scale structure revealed by the redshift surveys. Which star has the largest proper motion? Why? Answer: Barnard’s Star lies only about 6 light-years away, and the direction of its motion has a large component perpendicular to our line […]

Contrast the speeds of sound and light in watching a flash of lightning, then listening for the thunder to follow. One of the requirements of the Scientific Method is that an experiment must be ________. Answer: repeatable A supernova remnant, […]

Will the Sun become a brown dwarf? Explain. Describe the changes in the Sun from beginning to end of a sunspot cycle. Answer: The first spots appear at higher latitudes, 30-40 degrees above and below the equator. More spots appear, […]

Of what is the galactic halo composed? What role did Frank Drake play in SETI? Answer: Frank Drake developed the equation that attempts to provide the number of technological, intelligent civilizations now present in the Galaxy by breaking it up […]

List the three types of objects a star’s core can collapse to, and give the mass limits for each. What do gamma rays, X-rays, light, and radio waves all have in common? Answer: While they vary widely in wavelengths and […]

All nine planets in the solar system have been visited by spacecraft. Like our Moon and most others, all four large Jovian satellites have one side constantly fixed toward Jupiter as they revolve and rotate. Answer: FALSE The Schwarzschild radius […]

Why are type O, A, and M stars considered poor candidates to find a technological civilization? In going from Sa to Sc, the size of the ________ reduces significantly. Answer: nuclear bulge According to Newton’s third law, the Voyager probes […]

The proton storms in the solar wind travel at almost the speed of light. All four jovian planets are made primarily of hydrogen and oxygen. Answer: FALSE When plates collide, they fuse together and come to rest. Answer: FALSE The […]

We believe binary stars to be the ________ likely to have an extraterrestrial civilization. What do we mean by “life as we know it”? Answer: Our life is based on chains of carbon atoms with DNA, RNA, and proteins formed […]

Optically mapping the Milky Way is made very difficult because of ________ in the disk. If Sirius transits my local meridian tonight at 6:43 PM, when will it transit tomorrow? Answer: At 6:39 PM tomorrow night, as the Earth spins […]

A featureless spectrum, such as a rainbow, is said to be ________. The terrestrial planets have mantles of ________ materials and iron rich cores. Answer: silicates or rocky Contrast the observed visible mass of the Galaxy with its suspected total. […]

The spherical distribution of the globular clusters in the Halo reminds us of the similar distribution of cometary nuclei in the ________ cloud. In general, as a telescope’s diameter increases, its angular resolution ________. Answer: increases or improves. In 1998 […]

Which type of reflector telescope would be the easiest to construct, and why? How do radio interferometers greatly enhance resolution in radio wavelengths? Answer: Hooking two or more radio dishes together with a computer lets us get resolution not equal […]

According to Kirchhoff’s first law why do dense, hot bodies create the type of spectrum they do? Explain what a standard candle is and how it could be used to determine a galaxy’s distance. Answer: A standard candle is an […]

What three classes of stars are most likely to house life like ours? Why? Neutral hydrogen clouds appear ________ when viewed visually. Answer: transparent or clear Contrast the original and present uses of the Cosmological Constant. Answer: Originally Einstein added […]

Jupiter and the Sun have almost the same composition and density; why isn’t Jupiter also a star? When are Mercury and Venus easiest to observe from Earth? Why? How much of then can we see at that time? Answer: At […]

The scarps on Mercury are extremely similar to the cratered lunar highlands in appearance. The particles in Saturn’s E ring probably come from volcanic eruptions on Enceladus. Answer: TRUE Like the RR Lyrae stars, Cepheids are all similar in luminosity, […]

An absorption line spectrum, with dark lines crossing the rainbow of the continuum, is produced by a low-density hot gas. The parallactic angle is the total shift observed over a six-month interval. Answer: FALSE Because of their greater luminosity, RR […]

Why was the separation of the superforce into three forces so important? To explain its magnetic field, Europa must have an ocean of ________. Answer: (salty) liquid water Contrast the composition of stony and iron meteorites. Answer: Stony meteorites are […]

The ________ tides have a large change from high to low, near new and full moons. Contrast the rotation rates of the jovian planets with the terrestrial planets. Answer: All four jovian planets have a much faster rotation rate than […]

The spectral lines of a star indicate ionized helium is prominent, yet the star appears orange in color. Explain the problem with this and offer an explanation. A property common to active galaxies is that their energy is primarily ________. […]

Contrast image formation in reflectors and refractors. The tidal pull of the Sun largely cancels that of the Moon at the ________ phases. Answer: quarter When used in a single instrument to greatly enhance its resolution, the four separate mirrors […]

If its density suggests its core is similar to ours, why does Venus lack a magnetic field? High-precision observations by the Hubble Space Telescope have revealed what as-yet unexplained phenomenon in globular clusters? Answer: There appear to be three distinct […]

Due to our ozone layer, ultraviolet astronomy must be done from space. Only high-energy gamma rays can escape the event horizon of a black hole. Answer: FALSE Mercury’s magnetic field is generated by the same dynamo effect as Earth’s. Answer: […]

Harvard woman astronomer ________ discovered the period-luminosity relation. Mars appears red due to ________ on its surface. Answer: rust, or iron oxide If two observatories on opposite sides of the Earth were to measure the position of a star to […]

Describe the reasoning leading to the idea that the number of technological civilizations in the galaxy is equal to the average lifetime of a technological civilization. Why was deuterium so critical in the primordial nucleosynthesis? Answer: Formed at 900 million […]

Most millisecond pulsars are found in ________ star clusters. The primordial nucleosynthesis was sped up by the abundance of ________ in the universe once the temperature dropped below a billion K. Answer: deuterium Water is one of the most common […]

The universe has been expanding at the same rate since its formation. Although sunspots are cooler areas in the photosphere, when they increase in number that tells us the Sun is becoming more active. Answer: TRUE Earth-like planets have been […]

Fusion depends upon the ________ nuclear force getting the protons to stick together. How can the age of a star cluster be found from its H-R diagram? Answer: The older the cluster is, the farther down the main sequence the […]

An electron has a ________ electric charge. From a distance of 1 AU, the gravity of a three-solar-mass star is ________ the gravity of a lower-limit stellar black hole. Answer: the same as The Moon’s spin-orbit resonance shows it is […]

Earth is nearly twice as large as Venus. The density of white dwarf stars is about a million times that of the Sun. Answer: TRUE Venus’ surface temperature cools off at night, much like Mercury’s does. Answer: FALSE Interest in […]

Compare and contrast stars on the upper left and lower right of the main sequence. The ozone layer blocks much of the Sun’s ________ radiation. Answer: ultraviolet The spiral arms are made of bright stars belonging to Population ________. Answer: […]

The majority of dark matter is normal protons and neutrons. All modern large optical telescopes are refractors. Answer: FALSE Radio astronomy can only be done from up in space, due to our ionosphere. Answer: FALSE Comets are not actually members […]

State the cosmological principle. The ________ is the spherical outgassing as a comet nucleus is heated by the Sun. Answer: coma Because the interior of the Earth is ________, the crust is much less dense than the core. Answer: differentiated […]

The pulses from a pulsar are most likely coming from localized areas near the magnetic poles. At the solstices, the Sun’s declination will be 23.5 degrees from the equator. Answer: TRUE Galaxies are moving away from us and into the […]

What satellite revealed the most about cosmology, and why was it so effective? Stars that appear blue or white in color are ________ than our yellow Sun. Answer: hotter A galaxy with a blueshift is moving ________ Earth. Answer: towards […]

Supermassive galaxies are found at the core of rich galaxy clusters. An infinite universe is a basic assumption of the cosmological principle. Answer: FALSE There is new evidence that water has flowed as mud on Mars in recent times. Answer: […]

How is dust usually observed around young protostars in stages 4-6? Why aren’t there young stars in the halo? Answer: The halo contains virtually no dust, so star formation there ceased very long ago. Relate escape velocity to the event […]

Why might the Cassini-Huygens probe to Titan be considered disappointing to exobiologists? The mechanism by which planetary nebulae shine is very similar to that powering ________. Answer: emission nebulae The most abundant gas in the Earth’s atmosphere is ________. Answer: […]

The helium flash requires a core temperature of ________ K to create carbon. How are sunspots in the northern and southern hemispheres different? Answer: Sunspots always come in pairs, with one being a north pole and the other a south […]

Hydrogen lines are weak in M class stars because they have much less of it than do A class stars. The spectral lines of each element are distinctive to that element, whether we are looking at emission or absorption lines. […]

If a new wave arrives on shore every two seconds, then its frequency is 2 Hz. Our Sun will fade in luminosity as its supply of hydrogen drops in a billion years. Answer: FALSE Galileo’s observations of the entire phase […]

There are ground-based telescopes much larger than Hubble, yet the HST still reveals the faintest objects yet seen. Explain. Of the six layers of Earth, which is unique among the planets? Why? Answer: The hydrosphere, since liquid water is found […]

What evidence did probes to Mars find that makes it a prime candidate for life? The element erupting from the volcanoes of Io is ________. Answer: sulfur Name the four types of reflector designs. Answer: prime focus, Newtonian, Cassegrain, and […]

Changes in the predicted motion of Uranus led to the search for an eighth planet. Solar mass stars eventually become hot enough for carbon nuclei to fuse together. Answer: FALSE The “Great Wall” is the structure in the Large Magellanic […]

In the Bohr model of the atom, an electron can only exist in specific, well-defined energy levels. Like Titan, Triton has a nitrogen atmosphere. Answer: TRUE Paradoxically, while the core of the red giant is contracting and heating up, its […]

How do sound and light waves differ? From hottest to coolest, the seven letters for the star types are ________. Answer: OBAFGKM Most of the planets found orbiting other stars are similar to Jupiter, but ________ in temperature. Answer: hotter […]