Astronomy 111

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Celestial Coordinates

The celestial sphere is a tool that astronomers use to map the sky. To navigate the map, we need coordinates.  Maps of the Earth have longitude and latitude; the celestial sphere has right ascension (RA) and declination (Dec). To make sense of longitude and latitude, you first need to locate the North and South Poles.  … Continue reading Celestial Coordinates

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Celestial Sphere

Astronomers map the sky. Maps of the sky have aided navigators for thousands of years. They also let astronomers locate and identify astronomical objects such as stars, nebulae, and galaxies and plan astronomical observations. Backyard astronomers use sky atlases (likely digital) to find interesting objects in the sky. Professional astronomers map the sky so that … Continue reading Celestial Sphere

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Confidence

Confidence is a tricky concept, but it's also a pragmatic one.  We can never be 100% sure of anything, but we still need to get on with the business of living our lives.  There are bridges and airplanes and smartphones to build, and they all rely our current scientific theories.  We don't have certainty that … Continue reading Confidence

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Falsifiability

You may have learned in a previous science class that scientific hypotheses must make testable predictions. A less simplified statement is that scientific hypotheses must be falsifiable. Falsifiability is a cornerstone of science.  Start by reading the entry on the Criterion of falsifiability from Encyclopedia Britannica. I like to simplify the definition of falsifiable by … Continue reading Falsifiability