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1 of 5 Which of the following four diagrams most accurately depicts the shape of Earth's orbit around the Sun?

Common Misconceptions See the correct answer at the end of the page. Many people answer B, C, or D, but each of these is a common misconception. And here's the surprising news: the more astronomy education people have, the more likely they are to choose one of the erroneous ideas. Did you answer B? You know that the orbital path of Earth is nearly circular, but may still think that a large change in the distance between Earth and the Sun makes a big difference in how much the Sun warms Earth. Did you answer C? You may remember hearing or seeing that orbits are shaped like ellipses. Although Earth's orbit is elliptical, Earth and none of the other planets have orbits that are as elliptical as C. Only Pluto has a less circular orbit. Textbooks often exaggerate the elliptical shape that planets orbit to make this point clear. Also, instead of drawing the solar system from a top-down view, the solar system is sometimes drawn from an angle, making the nearly circular orbits look more like ellipses, just as any circle looks when viewed at an angle. Did you answer D? You may have combined the incorrect beliefs from B and C to generate a third misconception. In doing so, you might conclude that the warmer months of the year are because Earth moves closer to the Sun and that Earth's orbital path is elliptical because textbooks often represent it as such (see B and C above). Scientific Fact The correct answer is A. Earth's orbit around the Sun is nearly a perfect circle. Earth remains an average distance of 93 million miles (150 million kilometers) from the Sun throughout the year. Here's how others answered this question:  All teachers A. 5713 B. 708 C. 4996 D. 3721 =======  2 of 5 Which of the following responses most closely explains why it is hotter in New York in June than it is in December? A. The Sun gives off more heat energy in June. B. Earth is closer to the Sun in June. C. The Northern Hemisphere is closer to the Sun in June. D. The Sun is higher in the sky and and provides more hours          of daylight in June. Scientific Fact The correct answer is D. The angle at which the Sun's rays of light strikes Earth affects the temperature. When the Sun is high in the sky, its rays strike Earth almost perpendicular to the surface. In other words, the Sun's energy is more concentrated, causing any one spot to receive more light. When the Sun is low in the sky, its rays strike Earth at a more acute angle, causing the light to be more dispersed and any one spot to receive less light. Weather is also warmer in summer because the Sun, being higher, provides more hours of light as it travels a greater distance across the sky. This longer exposure to sunlight gives the land, seas, and air masses more time to absorb light, or warm, during the day. When the Sun reaches high in the sky and its rays of light (and heat) strike the ground nearly perpendicular to the ground (see diagram) we have summer. When the Sun at noon is low in the sky, its rays hit the ground at a more glancing angle, resulting in the warming action of these rays being spread out more; any one spot receives less heat (see diagram). We then have winter. You can do a quick hands-on demonstration of how this works by holding a flashlight vertically above a surface. Notice that the circle of light is concentrated when the flashlight is held vertically. Now, hold the flashlight at an angle to the surface. Notice how the light is less bright and spreads out when you hold it at an angle. Common Misconceptions When people answer A they may only be considering the heat source (the Sun), which means that they must also accept an uncomplicated explanation, such as the Sun simply makes more heat at certain times of the year. In fact, the Sun does not change its energy output during the year. People who answer B may also hold the misconception that Earth's orbit is highly elliptical (see question 1). This misconception probably leads to the conclusion that a large change in the distance between Earth and the Sun makes a big difference in how much the Sun warms Earth. In reality, the distance between Earth and the Sun hardly changes as Earth orbits the Sun in a nearly circular path. In fact, Earth is a little closer to the Sun when the Northern Hemisphere experiences winter. Those who answer C may have taken some astronomy and have learned that the tilt of Earth's axis has something to do with the change of seasons. If they believe that Earth's orbit is highly elliptical, they may have combined these two ideas. They may think that the tilt causes one hemisphere to be closer to the Sun, which would consequently cause that hemisphere to be warmer than the other one. In reality, Earth is so small and far away compared with the Sun that the difference in distance between the hemispheres is negligible. Here's how others answered this question:  All teachers  A. 193  B. 506  C. 7729  D. 6741 ========= 3 of 5 Put the following objects in the correct order, starting with the object that is closest to Earth. A. Moon, Sun, clouds, Pluto, stars B. Clouds, stars, Moon, Sun, Pluto C. Clouds, Moon, Sun, Pluto, stars D. Clouds, Moon, Sun, stars, Pluto Scientific Fact The correct answer is C. Stars are actually very distant suns--far more distant than Pluto. Common Misconceptions Judging distance in sky observations can be tricky, which is why many people incorrectly answer A, B, or D. Objects in the sky can also appear close or far away depending on whether you observe them near the horizon or higher in the sky. The developmental psychologist Jean Piaget found that very young children believe that the Sun, the Moon, and the stars are in front of the clouds. As we get older, we observe that closer objects, such as clouds, block objects that are farther away, such as the Moon and the Sun. But if you have never looked carefully at the sky, you may not have noticed this. As a result, those who answer A may believe that the Moon and the Sun are closer to Earth than the clouds are. Those who answer B are among the people who have some idea of distance but incorrectly believe that the Moon and the stars are close together because they appear to travel together across the night sky. Many people, adults and children alike, answer D. This may be because we have all been repeatedly told that Pluto is very far from Earth, so we assume that Pluto must also be farther than the stars. Here's how others answered this question:  All teachers A. 173 B. 678 C. 10827 D. 1986 ======== 4 of 5 Sometimes the Moon looks like this And sometimes the Moon looks like this What causes the Moon to change its appearance in this way? A. As the Moon orbits Earth, Earth's shadow covers the Moon. B. Clouds block part of the Moon from our view. C. As the Moon orbits Earth, we see different views of the Moon's           sunlit side.   Scientific Fact The correct answer is C. The changing proportion of the Moon's sunlit side that we see as the Moon orbits Earth causes the phases of the Moon. In a given year, however, you can expect the Moon to encounter Earth's shadow a minimum of 2 times and a maximum of 5 times. Common Misconceptions This idea that objects partly or completely disappear because something blocks the view is so reasonable that it may contribute to why many people incorrectly answer A or B. Those that answer A may know that a shadow is formed when an object blocks light from a light source. By holding an underestimated concept of the size-distance relationship between Earth, the Sun, and the Moon, these people may inocrrectly conclude that the Moon often falls into Earth's shadow. In fact, the Moon is so far away from Earth and compared with its size, the Moon falls into Earth's shadow a minimum of 2 times and a maximum of 5 times each year. Those who answer B may not have noticed that the Moon changes phase even on clear nights. Careful observations of the phases of the Moon and the sky conditions may rectify this misconception. Here's how others answered this question:  All teachers  A. 3014  B. 107  C. 10090  ========= 5 of 5 Which of the following diagrams most closely depicts the distance between Earth and the Moon?  Diagram A  Diagram B  Diagram C Scientific Fact The correct answer is A. Earth and the Moon are about 240,000 miles (roughly 387,000 kilometers) apart. In fact, 30 Earths laid end to end equal the distance between Earth and the Moon. Even though it seems that the Moon is huge when it is on the horizon, this is an optical illusion. You can check this by comparing the size of the Moon at the horizon and overhead with the tip of your pinkie held at arm's length. The Moon will be the same size. Common Misconceptions Many people incorrectly answer B or C. The misconception of distance may arise from visual representations--diagrams in books and three-dimensional models--that distort the distance to fit a model on a page or a tabletop. Those who answer B may derive this misconception from the types of representations mentioned above. With the diagram under response B to scale, the Moon would be less than half its actual distance from Earth, or about 112,000 miles (roughly 180,000 kilometers) away. Those who answer C may derive this misconception from the types of representations mentioned above. With the diagram under response C to scale, the Moon would be no more than 24,000 miles (about 39,000 kilometers ) away. Here's how others answered this question:  All teachers  A. 5410  B. 2911  C. 4303  TinyURL.com/privateUniverse