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The Sagan Series

The Sagan Series

Related:  Universe & Multiverse

SIMBAD Astronomical Database What is SIMBAD, and what is it not ? % The purpose of Simbad is to provide information on astronomical objects of interest which have been studied in scientific articles. Simbad is a dynamic database, updated every working day. Planets Large and Small Populate Our Galaxy (Infographic) Buy This Infographic as a Full-Size Poster Astronomers have discovered more than 700 alien planets beyond the solar system, and the count is rising all the time. Some are large and hot, and others are smaller and cooler, but scientists are still on the lookout for an Earth twin. They just got closer, with the announcement Dec. 5 of a planet found by NASA's Kepler space telescope to lie in the habitable zone around its star where liquid water, and perhaps life, could exist.

Geometry of the Universe Can the Universe be finite in size? If so, what is ``outside'' the Universe? The answer to both these questions involves a discussion of the intrinsic geometry of the Universe. Humans Left Africa Earlier, During Ice Age Heat Wave A warm spell during the Ice Age gave early humans a route out of Africa 20,000 years earlier than thought, say scientists who've uncovered a prehistoric tool kit in Arabia. During this period of climate change , about 130,000 years ago, water travel would have been easier than in more typical Ice Age periods. Seas in the region would still have been at relatively low, Ice Age levels, making for shorter crossings. On top of that, though, warmer, wetter weather would have created navigable lakes and rivers in what are now the deserts of the Arabian Peninsula, the study says. Such a shift would have offered early modern humans—which arose in Africa about 200,000 years ago—a new route through the formerly parched northern deserts into the Middle East.

The Absurdity of Infinity: Astrophysicist Janna Levin Explains Whether the Universe Is Infinite or Finite in Letters to Her Mother – Brain Pickings By Maria Popova In 1998, while on the cusp of becoming one of the most significant theoretical cosmologists of our time, mathematician-turned-astrophysicist Janna Levin left her post at Berkeley and moved across the Atlantic for a prestigious position at Cambridge University. During the year and a half there, she had the time and space to contemplate the question that would eventually become the epicenter of her career — whether the universe is infinite or finite. What began as a series of letters to her mother, Sandy, eventually became an unusual diary of Levin’s “social exile as a roaming scientist,” and was finally published as How the Universe Got Its Spots: Diary of a Finite Time in a Finite Space (public library) — a most unusual and absorbing account of the paradoxes of finitude. In an entry from September 3, 1998, Levin fleshes out her ideas on infinity and writes with exquisite Saganesque sensitivity to the poetics of science:

New Autogyro Is An Alternative to Flying Cars Never mind the flying car. It’s all about slowed-rotor/compound, according to Carter Aviation Technologies. SR/C is what the Texas company considers the key to a practical, personal transportation aircraft. Ancient Mass Extinctions Hint at Possible Ocean Future In sediment traces and fossil records from one of Earth’s most tumultuous periods, geologists have found a narrative linking mass extinctions with planetary biological and geological change. After dramatic oceanic extinctions 250 million and 200 million years ago, the global carbon cycle turned chaotic. Earth’s biogeochemistry went boom and bust for millions of years thereafter, as if some regulating mechanism were lost — which is exactly what happened.

The aliens are silent because they're dead Life on other planets would likely be brief and become extinct very quickly, say astrobiologists from The Australian National University (ANU). In research aiming to understand how life might develop, the scientists realised new life would commonly die out due to runaway heating or cooling on their fledgling planets. "The universe is probably filled with habitable planets, so many scientists think it should be teeming with aliens," said Dr Aditya Chopra from the ANU Research School of Earth Sciences and lead author on the paper, which is published in Astrobiology. "Early life is fragile, so we believe it rarely evolves quickly enough to survive."

Neanderthals cooked and ate vegetables 27 December 2010Last updated at 20:44 By Pallab Ghosh Science correspondent, BBC News Hunter, gatherer, vegetarian masterchef? Neanderthals cooked and ate plants and vegetables, a new study of Neanderthal remains reveals. Researchers in the US have found grains of cooked plant material in the teeth of the remains. The study is the first to confirm that the Neanderthal diet was not confined to meat and was more sophisticated than previously thought.