AS101 MIDTERM REVIEW

Speed of light = 3.0x10^5 Astronomical Unit (AU)+ 1 AU=1.5 x 10^11 m Quiz 1: Q: One number has three significant figures and another number has four significant figures. If these numbers are added, subtracted, multiplied, or divided, which operation can produce the greatest number of significant figures? A: the addition Assignment 1: Q: Why is scientific notation used in science? A: because it makes it easy to write very big or very small numbers Q: What is the approximate diameter of the Earth? A: 13,000 kilometres Q: Which one of the following statements best describes the moon? A: an astronomical body Q: Which one of the following statements best describes the Sun? A: generates energy by nuclear fusion Q: Approximately how many times larger than the diameter of a typical planet (the Earth) is the diameter of a typical star (the Sun)? A: 100 times Q: If the distance from the Sun to the Earth is represented by roughly 15 metres, then what would the distance from the Earth to the Moon on the same scale be? A: smaller than the width of your hand Q: Earth has a radius of about 6400 km, the Sun has a radius of about 7. 0×10 5 km, and a rubber ball has a radius of 6. 4 cm. If you were to construct a scale model of the Solar System using the rubber ball to represent Earth, what is the radius of a ball needed to represent the Sun in your model? A: 700 cm Q: How is a planet different from a star A: Planets reflect light, while stars produce their own light. Q: What is 5. 7×10 7 the same as? A: 57 million Q: If light takes 8 minutes to travel from the Sun to Earth, and over 4 hours to travel from the Sun to the planet Neptune, what is the distance from the Sun to Neptune? A: 30 AU Q: The speed of light is 3. 0×10 5 km/s, and it takes 1. 3 seconds for light to travel from the Moon to Earth. Based on this information, what is the distance from the Earth to the Moon? A: 390,000 km Q: How does one light-year relate to Astronomical Units, roughly? A: 63,000 AU Q: If the distance to a star is 450 light-years, what can we conclude about the star? A: The star's light takes 450 years to reach us. Q: If we say that an object is 1,000 light-years away, how does that affect how we see it? A:We see it as it looked 1,000 years ago. Q:Which statement best describes the study of astronomy in modern times? A:It has contributions from many cultures and countries. Q:What is the name of the hazy band of light that circles our sky, produced by the glow of our galaxy? A:the Milky Way Q:What is the reason for compressing the history of the universe into a single year in the cosmic calendar? A:to compare astronomical timescales with human experience Q:Using a cosmic calendar where the big bang happened at midnight January 1, at what time did human civilization emerge? A:30 seconds before midnight on December 31 Q:On the vernal equinox (March 21), where is the Sun on the celestial sphere? Assignment 2 A:on the celestial equator and moving north with respect to the equator Q:On the autumnal equinox (Sept. 21), where is the Sun on the celestial sphere? A:on the celestial equator and moving south with respect to the equator Q:At which of the following times would you find the Sun on the celestial equator? A:autumnal equinox and vernal equinox Q:At what two celestial locations do the celestial equator and the ecliptic coincide? A:vernal equinox and autumnal equinox Q:Why are Northern Hemisphere winters colder than Northern Hemisphere summers? A:The light from the Sun shines more directly on the Northern Hemisphere during the summer. Q:A scientific model is a mental conception that provides a framework that helps us think about some aspect of nature. A:True Q:If the apparent visual magnitude of a star is 7. 3, what does this tell us about the brightness of the star? A:It is not visible with the unaided eye Q:What is the apparent visual magnitude of a star a measure of? A:the star's brightness as seen by human eyes on Earth Q:If the apparent visual magnitude of star A is 3. 1, and the apparent visual magnitude of star B is 0. 5, how do star A and star B compare in terms of apparent brightness as seen from Earth? A:Star A is fainter than star B. Q:Where is the zenith for an observer standing at a point on the Earth's equator? A:directly overhead Q:If you were standing at the Earth's North Pole, which of the following would be located at the zenith? A:the north celestial pole Q:If you were standing on the Earth's equator, which of the following in the sky would pass through your zenith during the entire day (24 hours)? A:the celestial equator Q:An observer in the northern hemisphere watches the sky for several hours. Due to the motion of the Earth, this observer notices that the stars near the north celestial pole appear to move. What pattern does this apparent movement follow? A:counter-clockwise around the celestial pole Q:If the north celestial pole appears on your horizon, what is your latitude? A:0 Degrees