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MS Word
MS Word

... 3.2 Given the distance you just measured in Table 4 and the angular diameter in Table 3, calculate the true diameter for Capella and tell me how many times bigger than the Sun it is. ...
Review Sheet and Study Hints - Tufts Institute of Cosmology
Review Sheet and Study Hints - Tufts Institute of Cosmology

...  What information do you get from spectra of galaxies  How do stellar spectra relate to galaxy spectra  Why do interacting/peculiar galaxies show such a wide spread of colors  What are starburst galaxies  Evolution and Formation  Describe a theory about the formation of spirals.  What evidenc ...
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2.4 Statistical properties of radial velocity planets

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A Jupiter-mass companion to a solar-type star

Preview Sample 2
Preview Sample 2

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... Earth Minimum Orbit Intersection Distance (MOID) of 0.05 AU or less and an absolute V-magnitude of 22.0 or higher (indicating that they are greater than around 100m across). Most PHAs are detected after they have already passed the Earth. On August 7 1994, asteroid 1994 XM1 reached a minimum distanc ...
Investigate Planets, Stars, Galaxies, and the Universe
Investigate Planets, Stars, Galaxies, and the Universe

... and vast spaces. The observable universe contains billions of galaxies. These galaxies range in size from thousands of times smaller to a hundred times larger than our own Milky Way Galaxy, which itself contains more than 100 billion stars. Like our Sun, many other stars have planetary systems in or ...
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What we know about Jupiter

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Activity 1 - National Science Teachers Association

... knowledge of the neighboring planets that share our Sun. Robot spacecraft have flown past each of the planets, and orbited Mercury, Venus, Mars, Jupiter, and Saturn. Robotic spacecraft have landed on Venus and Mars. For the first time, we can compare their geological and meteorological conditions wi ...
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Earthfiles.com Science | WWII Was An ET Battle

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... that this is a voluntary choice based on his attitude. He refused to add epicycles. But now, of course, he had no model of the motions of the planets. Kepler realized that to get the most out of Tycho’s data, he first needed to determine the Earth’s orbit, since all planetary observations are made f ...
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Chapter 6 - Soran University

... the atmospheres of the four terrestrial planets and the four gas giant planets. The terrestrial planets are rich in heavier gases and gaseous compounds, such as carbon dioxide, nitrogen, oxygen, ozone, and argon. In contrast, the gas giant atmospheres are composed mostly of hydrogen and helium. ...
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click here

... longer than Kelvin assumed by assuming the Earth was just cooling off from its formation. By 1926, the accepted radioactive age of the Earth was 4.5 billion years, much longer than either Kelvin or Darwin has argued for. ...
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AWG recommendation on Cosmic Vision

... detecting planets with ever smaller masses, and towards the development of a broader suite of techniques to characterize their properties. There is no doubt that this trend will continue into the next two decades, as substantial technological challenges are progressively overcome. After Corot will h ...
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Spiral Galaxies - Astronomy Centre

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In the icy near-vacuum of interstellar space are seething

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Chapter 1 Clicker Questions
Chapter 1 Clicker Questions

... No, the light from the solar system has not yet reached Andromeda. No, the light from the solar system that has reached Andromeda came from a time before Earth had formed. No, radio signals from terrestrial civilizations have not yet reached Andromeda. Yes, in principle. With sufficiently powerful t ...
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American Scientist

... outclassed by nature. Dust grains do not seem to readily stick. Even if rocks form, they then drift into the star much too quickly, fast enough to preclude their coalescence into larger objects. These larger, kilometer-sized objects, known as planetesimals, are in princi- ...
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... Earth’s Orbital Motion The Twelve constellations (some say thirteen) that the Sun moves through during the year are called the zodiac; The view of the night sky changes as Earth moves in its orbit about the Sun. As drawn here, the night side of Earth faces a different set of constellations at diffe ...
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10 New Constellations

... the primary component is a blue star with a radius 3 times greater than our sun with surface temperatures more than twice as hot. Alpheratz is officially the brightest star in Andromeda, it is also considered as part of Pegasus as it connects both constellations. M31 The most interesting object in t ...
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Detecting Earth Mass Planets with Gravitational

Lecture 15a - Sierra College Astronomy Home Page
Lecture 15a - Sierra College Astronomy Home Page

... The problem with all these hypotheses (of aliens watching us quietly) is that galactic shear would move us to new stellar systems in a few million years; enforcement of a “DO-NOT-CONTACT-EARTHLINGS” rule would require cooperation at a galactic scale. In other words, if you think we are being quietly ...
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Rare Earth hypothesis



In planetary astronomy and astrobiology, the Rare Earth Hypothesis argues that the origin of life and the evolution of biological complexity such as sexually reproducing, multicellular organisms on Earth (and, subsequently, human intelligence) required an improbable combination of astrophysical and geological events and circumstances. The hypothesis argues that complex extraterrestrial life is a very improbable phenomenon and likely to be extremely rare. The term ""Rare Earth"" originates from Rare Earth: Why Complex Life Is Uncommon in the Universe (2000), a book by Peter Ward, a geologist and paleontologist, and Donald E. Brownlee, an astronomer and astrobiologist, both faculty members at the University of Washington.An alternative view point was argued by Carl Sagan and Frank Drake, among others. It holds that Earth is a typical rocky planet in a typical planetary system, located in a non-exceptional region of a common barred-spiral galaxy. Given the principle of mediocrity (also called the Copernican principle), it is probable that the universe teems with complex life. Ward and Brownlee argue to the contrary: that planets, planetary systems, and galactic regions that are as friendly to complex life as are the Earth, the Solar System, and our region of the Milky Way are very rare.
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