THE SOUTHWORTH PLANETARIUM 207-780-4249 www.usm.maine.edu/planet <http://www.google.com/url?q=http%3A%2F%2Fwww.usm.maine.edu%2Fplanet&sa=D&sntz=1&usg=AFQjCNHulkHuLP13bOG2PkNrPazsGWFs2A> 70 Falmouth Street Portland, Maine 04103 43.6667° N 70.2667° W Altitude: 10 feet below sea level Founded January 1970 Julian Date: 2458977.16 2019-2020: CXLIII THE DAILY ASTRONOMER Friday, May 8, 2020 Remote Planetarium 30: Week 6 Quiz What are we waiting for!? This quiz is bound to be delightful. Let's begin! *1. The lowest level of Earth's atmosphere is called the _________________* a. troposphere b. stratosphere c. mesosphere d. ionosphere *2. What is the difference between a "meteor" and a "meteoroid?"* a. a meteor is found on the ground; a meteoroid is found in space b. a meteor is the light produced when a meteoroid infiltrates the atmosphere c. a meteorite is found in the air; a meteor is found in space d. there is no difference between them. *3. What is the "radiant?"* a. the observer's zenith b. the belt from which comets originate c. the apparent convergence point from which meteors appear to emanate d. the central point within a constellation boundary *4. A meteor shower is named after __________________* a. the astronomer who first identified the shower b. the comet from which the shower's meteoroids originate c. the date on which the shower peaks d. the constellation or the star from which the meteors appear to emanate *5. Within which layer of the atmosphere would one tend to find the aurora borealis?* a. stratosphere b. mesosphere c. thermosphere d. exosphere *6. When in prograde motion planets appear to move _______________* a. west to east b. east to west c. north to south d. south to north *7. How much more accurate was the Copernican solar system model than the Ptolemaic one?* a. not more accurate at all and sometimes slightly less accurate b. much more accurate! c. it was far more accurate with the inner planets, but just as inaccurate with the outer planets d. it was far less accurate with the inner planets, but much more accurate with the outer planets *8. If you observed Venus through a telescope, what would you see?* a. a crescent or a "half" Venus b.the planet resembling a full circle c. nothing. Venus isn't observable telescopically d. a bright green disc *9. Who is credited with formalizing the solar system model that included epicycles?* a. Isaac Newton b. Galileo Galilei c. Johannes Kepler d. Claudius Ptolemy *10. The model of the solar system that places the Sun in its center is called *________________. a. heliocentric b. geocentric c. solarcentric d. epicentric *11. Which two planets can transit the Sun from our perspective?* a. Mercury and Mars b. Mercury and Venus c. Mars and Jupiter d. Jupiter and Saturn *12. Astronomers observed the transit of which planet in order to determine the Sun's distance?* a. Venus b. Mars c. Jupiter d. Saturn *13. A transit of Venus occurred in which two of the following years?* a. 1713 b. 1761 c. 1769 d. 1783 *14. What is an "astronomical unit?"* a. the mean separation distance between Earth and the moon b. the mean separation distance between Earth and the Sun c. the mean separation distance between Earth and Venus d. none of the above *15. Kepler''s Third Law of Planetary Motion states that the square of a planet's period is proportional to ____________________* a. the square of its mass b. the square of its average distance from Earth c. the cube of its semi major axis (average distance from the Sun) d. its momentum *16. How many Earth-sized spheres could fit inside the Sun?* a. 100 b. 10,000 c. 120,000 d. 1.2 million *17. The Sun is how many times more massive than Earth?* a. Twice as massive b. 100,000 times as massive c. 333,000 times as massive d. 1.2 billion times as massive? *18. How can we know the chemical composition of the Sun?* a. we've sent probes to the Sun to collect samples b. by studying its spectra c. by capturing material expelled by solar flares d. by examining the sunlight reflected off the moon *19. What happens to an atom when it absorbs a photon?* a. the atom explodes b. an electron within the atom is elevated to a higher energy orbit c. the atom's atomic number changes d. nothing happens at all *20. The two most common elements in the Sun are * a. hydrogen and helium b. hydrogen and oxygen c. carbon and hydrogen d. helium and neon ANSWERS *1. The lowest level of Earth's atmosphere is called the _________________* a. troposphere Earth's atmosphere is divided into layers. The bottom layer, the one in which we live, is the "troposphere." The next layer is the stratosphere, followed by the mesosphere, thermosphere and finally exosphere. The ionosphere extends from the upper mesosphere to the exosphere. *2. What is the difference between a "meteor" and a "meteoroid?"* b. a meteor is the light produced when a meteoroid infiltrates the atmosphere The three definitions: - *Meteoroids:* particles in outer space flaked off from comets or asteroids. These are meteoroids when suspended in outer space. - *Meteors:* the lights we see when meteoroids infiltrate the upper atmosphere (between 250,000 - 330,000 feet) - *Meteorites: *fragments of meteoroids that survived the descent through the atmosphere and are found on Earth's surface 3*. **What is the "radiant?" * c. the apparent convergence point from which meteors appear to emanate Even though the meteors travel along a path parallel to Earth's surface they appear to emanate from a specific point in the sky called the "radiant." *4. A meteor shower is named after __________________* d. the constellation or the star from which the meteors appear to emanate Meteor showers are quite often named for the radiant's host constellation. Some, however, are named for the prominent star closest to the radiant, such as the Eta Aquarids which peaked earlier this week. *5. Within which layer of the atmosphere would one tend to find the aurora borealis?* c. thermosphere The aurora borealis occurs between 90 - 150 kilometers above Earth's surface, within the thermosphere, the layer just above the mesosphere. *6. When in prograde motion planets appear to move _______________* a. west to east The planets don't actually appear to move throughout a single night. However, over many nights they shift their positions relative to the background stars, hence the word "planet" that derives from the Greek word for "wanderer." Planets generally move west to east (prograde motion.) However, at times, planets will exhibit westward motion when they are moving in a retrograde fashion. *7. How much more accurate was the Copernican solar system model than the Ptolemaic one?* a. not more accurate at all and sometimes slightly less accurate The Copernican system did place the Sun in the solar system's center. However, it still described the planetary orbits as circular, not elliptical, hence the inaccuracy. *8. If you observed Venus through a telescope, what would you see?* a. a crescent or a "half" Venus If you observe Mercury or Venus in a telescope, either one will appear as a crescent, not a full planet as each one is closer to the Sun than Earth. *9. Who is credited with formalizing the solar system model that included epicycles?* d. Claudius Ptolemy Ptolemy formalized a system developed by two equally clever mathematicians: Apollonius of Perga and Hipparchus of Rhodes. This system included such clever contrivances as deferents, epicycles and equants. *10. The model of the solar system that places the Sun in its center is called *________________. a. heliocentric The heliocentric model puts the Sun in the solar system's center. It is named for Helios, the god of the Sun. *11. Which two planets can transit the Sun from our perspective?* b. Mercury and Venus Only inferior planets, those closer to the Sun than Earth, can appear to transit (move directly in front of) the Sun. *12. Astronomers observed the transit of which planet in order to determine the Sun's distance?* a. Venus [image: venustransit.jpg] By observing the transit of Venus from different stations astronomers were able to derive a value for the Sun's average distance. *13. A transit of Venus occurred in which two of the following years?* b. 1761 c. 1769 Transits of Venus generally occur in 8 year pairs separated by more than a century, The following transit years after 1769 1874 1882 2004 2012 2117 2125 *14. What is an "astronomical unit?"* b. the mean separation distance between Earth and the Sun This value approximately equals 93 million miles. *15. Kepler''s Third Law of Planetary Motion states that the square of a planet's period is proportional to ____________________* c. the cube of its semi major axis (average distance from the Sun) This relation is also known as the "harmonic law." The square of a planet's orbital period (in years) equals the cube of its semi major axis (mean distance) in Earth years. *16. How many Earth-sized spheres could fit inside the Sun?* d. 1.2 million The Sun is immense! Gargantuan! Inconceivably big! Remarkably, as we'll learn, the Sun is minuscule compared to some stars. *17. The Sun is how many times more massive than Earth?* c. 333,000 times as massive The Sun is immense! Gargantuan! Inconceivably big! *18. How can we know the chemical composition of the Sun?* b. by studying its spectra [image: sun_spectrum_1.jpg] Each atom absorbs light at specific wavelengths. By studying the Sun's spectra, astronomers can determine which elements are present in its outer layers. *19. What happens to an atom when it absorbs a photon?* b. an electron within the atom is elevated to a higher energy orbit [image: download.png] Photon absorption "excites" the atom by elevating one of its electrons to a higher energy orbit. Each atom absorbs only those photons whose energy equals the energy difference between its electron's "orbits." *20. The two most common elements in the Sun are * a. hydrogen and helium The Sun is almost 91% hydrogen and 8.9% helium by volume. By mass, the Sun is 70.6% hydrogen and 27.5% helium To subscribe or unsubscribe from the Daily Astronomer: https://lists.maine.edu/cgi-bin/wa?SUBED1=DAILY-ASTRONOMER&A=1