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The bumpy road to becoming a star As a nebula collapses, there are forces which resist the collapse. Things like rotation, ionization and heat can overwhelm gravity and keep a given chunk of dust and gas from ever managing to start nuclear fusion and become a star. Those same forces, if the cloud manages to …
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Oh where o where did our sun come from? In episode 59, we talked about the “rare Earth hypothesis.” According to that school of thought, when and where a star is born, and when and where it lives, matters. Our Sun apparently showed up after a very active epic of star formation. This may have …
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How to make a mind—part2 What we need is our rare and wonderful Earth, and approximately 4.54 billion years. Of course, that begs the question. How did we end up with our Earth, and how important is it that a planet is like our Earth to create intelligent tool users? According to the “Rare Earth …
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Can’t we just look at it? In episode 56 and episode 57, we looked at a couple of methods of detecting planets that are orbiting around stars other than our own sun. These methods involve a good deal of analysis and inference. Today, we learn about how astronomers can look directly at a planet around …
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The hunt for planet tomato Unlike the method described in the previous episode, the transit method allows one to look at many stars at a time. When a planet crosses between us and the star it’s orbiting, the star’s light dims very slightly. If we can detect that dimming, we can detect said planet. Here’s …
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The stars wibble and wobble as their planets go round There are several ways of detecting planets that orbit stars other than our sun. One method, called Doppler spectroscopy, relies on the fact that an orbiting planet causes its star to wobble. Spectrometers are used to observe the spectral lines within the stars light, (see …
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The search for Planet 9 @AntonyTheReal_ showed me a video recently, in which one of the folks was rather upset with NASA. It bothered him that they were presenting details of a planet orbiting another star, lightyears away, while at the same time, we’re still not certain whether or not there is a ninth planet …
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Irrational computers, investing, and racist robots It’s easy to assume that computers and computer software, being without emotions, are more rational than we are. However, our software systems are like children of the mind, and they inherit our bias and irrationality. In fact, since they cannot judge context, they are less rational than we. Here …
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Complex analysis, the stock market, and seeing what you expect Two theories about the stock market, the efficient market hypothesis and technical analysis, are each attempting to analyze the same complicated system—namely the stock market and the fluctuations of different share prices in different companies. Both theories start by assuming that the price always reflects …
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More about the dark side In 1933 Fritz Zwicky was studying the motion of galaxies within the Coma Cluster. He found that the motion could only be explained if there was considerably more mass present than what could be observed. Later, in the late 1970s, Vera Rubin was observing the rotational dynamics of the andromeda …