ASTR 1504/1514: Astronomy: Exploring the UniverseMidterm Exam 11. Is there any location on Earth where the entire sky is potentially visible within a 24hour period (ignoring the fact that most stars can’t be seen if it is daytime)?• A: There is no position on the Earth where it is possible to see the entire sky inone daily rotation of the Earth.• B: At a latitude of either 45 degrees North or South.• C: At the equ at o r• D: At either the n o r t h or south pole2. A crucial component of a scientific theory is that it is able to be tested by observationsand t hus proven true or false.• A: True• B: False3. Constellations are arbitrary groupings of stars in the sky.• A: True• B: False4. The seasons on Earth are caused by the change in distance between the Sun and Earth.• A: True• B: False5. The eclip t i c plan e is defined by the motion of which object in the sky.• A: the Moon• B: the Sun• C: Polaris• D: the stars6. If you go out at exactly 9 P.M. each evening over the course of one month, the positionof a given star will move westward by tens of degrees. What causes this motion?• A: The Earths rotation on its axis• B: The revolution of the Earth around the Sun• C: The revolution of the Moon around the Earth• D: The revolution of the Sun around the Earth7. The Moon undergoes synchronous rotation, and as a consequence the:• A: rotational period of the Moon equals the orbital period of the Moon aroundthe Ear t h• B: rotational period of t h e Moon equals the rotational period of t he Earth• C: rotational period of the Moon eq u al s the orbi t al period of th e Earth arou n dthe S u n• D: Moon does not rotate as it orbits the Earth8. If tonight t he Moon is in the waxin g gibbous phase, in thr ee days the Moon will m o stlikely be in the:• A: new phase• B: full phase• C: third quarter phase• D: first quarter phase9. During which lunar phase do solar eclipses occur?• A: New• B: First quarter• C: Full• D: Third quarter10. When the Earth catches up to a sl ower moving outer pla n et and passes it in i t s orbitlike a faster run n er overtakes a slower runner i n an outsid e lane, the planet:• A: exhibits retrograde motion• B: slows down because it feels the Earths gravitational pull• C: decreases in brightness as it passes through the Earths shadow• D: moves into a more el l i p t i cal orb i t11. If the Sun is located at one focus of Earths ellipt ic al orbit, what i s at the other focus?• A: Earth• B: The Moon• C: Nothing• D: This is a trick question. An ellipse has only one focus.12. Which o f the following is TRUE about a comet that is on an elliptical orbit aroundthe S u n ?• A: The comets speed is greatest when it is farthest from the Sun.• B: The comets speed is greatest when it is nearest the Sun.• C: This comets speed is zero.• D: The comets speed is constant because its mass an d the Suns mass stay ap -proximately the same.13. What fo rc e hold s planet s in their orbits?• A: Air resistance• B: Friction• C: Electromagnetic• D: Gravity14. In which of the following situations would the object be experiencing an unbalancedforce?• A: A truck at rest• B: An car moving at constant speed turning a corner• C: A rocket moving at a const a nt speed straight up away from the Ea r t h• D: A car moving at a constant speed towards the right15. Once two objects are far enough away from each other, they no longer exert anygravitational attraction on each other.• A: True• B: False16. A rad io phot o n travels more slowly than a gamma ray photon in vacuum.• A: True• B: False17. The en er gy of a photon is inversely proportional to its wavelength.• A: True• B: False18. The an gular resolution of a ground-based telescope is usually set by:• A: diffraction• B: refraction• C: the focal length• D: atmospheric seeing19. How do the wavelength and frequency of red lig ht compare to the wavelength andfrequency of b lue light?• A: Red light has a longer wavelength and h i gh er frequency than those of bluelight.• B: Red light has a longer wavelength and lower frequency than those o f blue light.• C: Red light has a shorter wavelength and higher frequency than those of bluelight.• D: Red light has a shor te r wavelength and lower frequency than those of blu elight.20. What ca u ses molecu l ar clou d s to collapse?• A: Conservation of charge• B: Self-gravity• C: Thermal energy• D: Radiation21. What happens to the gravitational energy of gas as it falls toward and eventually hitsthe accr et i on disk surr ounding a protostar?• A: It is converted into thermal energy, heatin g the disk.• B: It is converted into light energy, giving off a flash of light upon im pact.• C: It is converted into potential energy as the gas plows through the disk andcomes ou t the other side.• D: It simply dissipates.22. What s et s the temperature of the pocket of gas in a protoplanetary disk?• A: Its distance from the forming star• B: How much gravitational energy was converted to heat• C: How much radiation from the forming star shines on the g as• D: All of the above23. Current technology is sensitive enough to detect some extra-sol ar planets by a dip inbrightness of the parent star as th e planet s pass between us and it.• A: True• B: False24. The angular momentum of a planet depends on its mass and its distance from the Sun.• A: True• B: False25. Ocean tides o n Earth are caused only by the Moon.• A: True• B: False26. Which of the following is NOT a factor that helps explain Ear t h s lack of craters com-pared to th e Moon?• A: Wind erosion• B: Larger atmosphere• C: Higher density interior• D: Tectonic Activities27. Earths innermost core is solid, not liquid, because:• A: the core temperature is too low to melt iron• B: differ entiation caused all of the heavy, solid material t o sink to the bottomwhile Earth was forming• C: all the liquid has moved up into the m antle via convection• D: the pressure is too h i gh for a liquid state28. You discover an Ear th-like planet around another star, but the planet has twice themass of Earth. What would you NOT expect to see?• A: A highly cratered surface.• B: An atmosphere.• C: Volcanoes and tectonic plates.• D: Erosion and weathering.29. A visible light photon has a frequency of 6×1014Hz. If this photons energy is equivalentto 1 penny, what is the energy of an X-ray photon at 6 × 1019Hz?•