ASTRO I
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- 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
- Midnight.
- 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
- 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?
- Mercury.
- 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?
- Venus.
- 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?
- Kepler
- Aristotle
- 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?
- Aristarchus.
- 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?
- mass
- 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:
- infrared.
- Asteroids:
- 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?
- None.
- How many moons are larger than Mercury?
- 2
- 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:
- Earth.
- 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?
- Triton.
- 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?
- 2.
- 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?
- Ionosphere.
- Infrared light from the Sun and the Earth are mainly absorbed in which layer of the Earth's atmosphere?
- Troposphere
- 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?
- Callisto.
- 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?
- Mercury.
- 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?
- Io.
- The largest mountain in the solar system is:
- Olympus Mons.