# Astronomy

• Astronomy
First, of all the planets around the Sun, the Earth has, through the laws of physics, maintained an atmosphere. This atmosphere serves two specific purposes in sustaining life. First, it protects...

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Astronomy should be studied by mankind because our survival is directly linked to the cosmos. The Earth is heated by its nearest star, the Sun, and its ocean tides are directly connected to its...

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The most commonly accepted theory on the formation of the universe is what is known as "the Big Bang" theory. Many astronomers believe that the origins of the universe began with the concentration...

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I assume we watched the same episode. If you will continue to watch that you will see that the aliens probably a century or a millenium advanced that our civilization. But we are not sure neither...

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Around 1859 the German chemists Robert Wilhelm Bunsen and Gustav Robert Kirchhoff began to examine the light generated when elements were heated to incandescence. By passing that light through a...

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According to the enotes dictionary, the definition of a system is that it is "A group of interacting, interrelated, or interdependent elements forming a complex whole" The concept of a system is...

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The Doppler Effect is evidence that the universe is expanding. When stars or galaxies are moving away from us, we see their color as red shifted. Because the distant galaxies are red shifted, this...

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I think most people would be surprised to find out that the most volcanically active body in the solar system is actually one of Jupiter's moons, Io. It has more than 400 volcanoes, and the amount...

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There is overwhelming physical evidence that the universe is changing. The debate among astronomers is over whether the universe is expanding, a completely different question. The universe is...

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Earth's temperature would not change considerably in either scenario, as these rays produced by the sun do not reach the Earth's surface due to the planet's thick atmosphere. The sun's corona...

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A lot of scientists believe that the major example of how this happened was the asteroid impact that (many believe) had a lot to do with the extinction of the dinosaurs. The way this works is...

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We have yet to discover another planet which can support human life. Those explored thus far have all been too close to the sun, too far away, had too little oxygen, too dense of an atmosphere, or...

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The question of who invented the first calendar is very hard to answer -- no one knows for sure. Many ancient societies had them. The Egyptians are, however, credited with the first solar...

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There have been many arguments regarding whether or not Pluto is a planet. It is currently defined as NOT being a planet but instead part of what is the Kuiper belt. Pluto is thought to be composed...

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The three layers of the sun's atmosphere are the Photosphere, Chromosphere, and Corona. The Photosphere contains the sunspots, the Chromosphere, the solar flares, and the Corona contains the solar...

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Astronomical Units (AU) and Light-Years (ly) are both measurements of distance, generally used to show large amounts of distance between points. Light-years are better suited for calculating the...

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There are nine different stages that a star must pass through before being “born.” The first stage is when a nebula collects and makes a mass of gas and dust then it begins to contract under its...

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Both Black holes and neutron stars are product of a dying star. When a star dies, it spent all of its energy and then collapses. Their difference lies on their parent star. For the purpose of this...

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Some of the options provided are completely false, others are true, but were not discovered by Newton. Newton's discovery was D, that gravity is a universal phenomenon. While it is true that all...

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Nicolaus Copernicus's knowledge was to set the scene for major advances in science. Copernicus also marked the beginning of a scientific revolution and astronomy.

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Actually, the recently retired space shuttle line of space vehicles never landed on the moon. The lunar landings were conducted between 1969 and 1972 with the Apollo missions. The space shuttle...

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Our sun has no moons. It has planets that revolve around it and the moons then revolve around the planets. Currently, most scientists consider eight objects that orbit the sun to be planets but...

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Seems like this would be an easy question for you to find the answer yourself. In fact, if you had typed your question into the search box on the eNotes home page, you would have been directed to a...

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Even though the Sun is much farther away from the Earth than the Moon, it exerts a stronger gravitational pull because it is so huge. However, the sun exerts a smaller tidal influence on Earth...

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The force exerted by the moon on the Earth is 2.98 x 10^31 joules. The gravitational force exerted by the Earth on the Sun is 3.58 x 10^23 joules These figures are derived by using the following...

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The most commonly believed theory on this among scientists is what is known as the "big bang" theory. This idea holds that the universe was created by a huge explosion. The universe, according to...

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The Martian Year can be expressed either in Earth Days (It takes 686.9726 Earth days for Mars to complete an orbit of the Sun.) But the Martian Day is different also, about 24 (Earth) hours and...

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"After the solar nebula collapsed to form our Sun, a disk of material formed around the new star. The temperature across this protoplanetary disk was not uniform. Since different materials condense...

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Question one regards barycentric coordinates. The center of mass in the Sun-Earth relationship is not at the center of either body; it is a sort of average between the two. I can tell you without...

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We understand that the word “retrograde” means moving backwards, or moving in the opposite direction in consideration to something else. So understanding planet retrogrades is difficult because...

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It is a highly ambitious dream to follow, but never lose hope. There are opportunities aplenty for budding astronomers, as the field of astronomy is a relatively young one and thus, has thousands...

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In astronomy, a parallax refers to the angular distance between a celestial body and the observation point at earth's surface. Since we see the celestial body up in the sky, we measure the distance...

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When a star like our Sun reaches the final phase of its life, it burns out its supply of hydrogen and it begins to cool down and expand. This phase is called a red giant. The core begins to...

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It isn't that Pluto died per se. Instead, Pluto is what it always has been—or at least, what it has been for millions, perhaps billions, of years. It's a small, rocky, planetoid. What happened was,...

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Pluto was reassigned as a dwarf planet because a new definition of the term planet. TRUE

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The angular diameter of an object is the size of the object expressed as an angular measurement when it is viewed from a particular spot. If an object is at a distance D from the point it is being...

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The period of a planet orbiting a round a star, for example, the Sun, relates to th=e radius of the orbit according to the third Kepler's Law: T^2 = (4pi^2)/(GM) a^3 Here, T is the period of the...

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Comets have tails (two of them, in fact) because of stuff coming off the comet's core. One of the tails is made of dust. The other tail is made of gasses. Both of these tails point more or less...

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Russian Yuri Gargain was the first man to orbit the earth. He orbited the earth once before returning to earth about 90 minutes later.

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Simply put, a galactic year it is the Sun's period of rotation around the center of the Galaxy, equal to about 225 million years. The Wikipedia blog states: “The galactic year is the duration of...

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Using the stars to tell time is actually very complicated (much more difficult than using the sun or the moon). Whereas using the sun to denote time is relatively simple (when the sun is directly...

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According to the IAU (International Astronomical Union) Saturn, which is the sixth planet from the sun has "18 known moons that have received officially sanctioned names." The most famous of the...

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An interesting question. We can't be sure, of course, because we've only had the tools to observe the sun across a wide range of the electromagnetic spectrum for a short time, and therefore have...

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The answer to the question is A. While it is true that there are large impact craters all over the world and the Earth's magnetic poles have reversed several times over the course of geological...

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Newton realized that two bodies orbit around a common center of mass, rather than one round the other. He therefore modified Kepler's 3rd Law to: (m1 + m2) P^2 = (d1 + d2)^3 = R^3 where R is the...

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Absolutely false! Johannes Kepler (1571-1630) who lived a generation before Isaac Newton, was first to accurately describe the motions of the planets in his Three Laws of Planetary Motion in 1619....

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The Sun produces heat in its core through the process of nuclear fusion. "Nuclear fusion is the process by which two light atomic nuclei combine to form one heavier atomic nucleus. As an...

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The mass of Earth's moon is 7.36 xx 10^22 kg. The Moon's Radius is 1.74 xx 10^6 m. The mass of the Earth is 5.98 xx 10^24 kg, and its radius is 6.37 xx 10^6 m. According to Newton's law...