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July 2014 BRAS Newsletter - The Baton Rouge Astronomical Society
July 2014 BRAS Newsletter - The Baton Rouge Astronomical Society

... in their paper published in Proceedings of the National Academy of Sciences, but it “seems unlikely to be unrealistic by more than a factor of 2.” Even planets with shorter orbital periods could also be in the habitable zone, the authors note, for example, around stars of very different spectral typ ...
PH607 – Galaxies
PH607 – Galaxies

... Many theories which seek to extend our current understanding of particle physics predict new particles, often with masses comparable to those of the W and Z bosons (around 100 GeV 100 times the mass of a proton). In many cases the lightest of these new particles is stable, never decaying to lighter ...
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The Sky Viewed from Earth - Beck-Shop

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... making in the 16th century, a north-south line through Greenwich became the world standard for measurements of longitude. Today, the Greenwich meridian, also known as the prime meridian, has become the reference line from which longitude is measured, as you can see in Figure 2-7. Lines of equal long ...
Extremely Large Telescopes
Extremely Large Telescopes

... • 60m could reach mH~29 in 100hrs (depending on source size) • Spectroscopy at z>10 hard even for 100m The Universe at z=6.1 (Gnedin 2000) Neutral H, ionising intensity (z), gas density, gas temperature ...
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January

... Except for the probes that have been sent to the planets, astronomers cannot reach out and touch their experiment, which is the universe itself. One of the key measurements in Astronomy is distance. To measure distances, the astronomer must rely on the light from any object. Distances are then deter ...
Final review - Physics and Astronomy
Final review - Physics and Astronomy

... 2) It predicted the cosmic microwave background radiation, its uniformity, its current temperature, and its black-body spectrum. 3) It predicted the correct helium abundance (and lack of other primordial elements). ...
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... that traverses the image – this beam of matter is called a jet. It consists of ultra-hot gas and magnetic fields, ...
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HR Diagram and Stellar Fusion

... • …Ejnar Hertzsprung and H. N. Russell, graph (see illustration) showing the luminosity of a star as a function of its surface temperature. The luminosity, or absolute magnitude, increases upwards on the vertical axis; the temperature (or some temperature-dependent characteristic such as spectral cl ...
Word Document - Montana State University Extended
Word Document - Montana State University Extended

... The Rare Earth hypothesis suggests that Earth-like planets containing complex (animal) life as we know it are likely quite rare in the Universe. This lesson will explore several parameters that have led the scientists Peter Ward and Donald Brownlee to put forth this hypothesis in their book, Rare Ea ...
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Evan_Skillman_1

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Science Olympiad 2008 Reach for the Stars Division B

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uv surface environment of earth-like planets orbiting
uv surface environment of earth-like planets orbiting

... considered to have a biological source. 2.2. Simulation Set-up We focus on four geological epochs from Earth’s history to model the UV environment on the surface of an Earth-like planet at the 1 AU equivalent distance from its host star. The geological evidence from 2.8–3.5 Ga is consistent with an ...
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... 1. What determined the temperature of your planets? 2. Did your planets come to an equilibrium temperature? What is happening at that temperature? 3. If your sun got hotter, would the temperature change? How? 4. If your planet got farther away, would the temperature change? How? 5. What conclusion c ...
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Planets, Moons, and Stars

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Planetary motion - Inside Mines

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RealOccultdark - Montgomery College

... profile very accurately so that when solar eclipses happen and the last part of the photosphere appears in deep lunar valleys, forming Baily's Beads. The timing of these Baily's beads can be used to tell whether the sun is getting larger or smaller over time, by comparing Baily's beads timing from s ...
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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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