Archive: » 2015 » February

March Sky

I generally comment on the night sky in these posts, but the major astronomical event in March is the total solar eclipse on 20 March, so I am going to focus on that. There are two types of solar eclipse - total eclipses and all the rest. It is a remarkable coincidence that the apparent diameters of the sun and moon are so similar that when they are lined up precisely in a total eclipse, the bright photosphere that is all we see of the sun most of the time is completely obscured, allowing the pink chromosphere that surrounds it, including prominences arching from it, and the wispy corona beyond,...

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February Night Sky

Jupiter comes to opposition on 6 February, on the Cancer/Leo border. At magnitude -2.6 it is unmistakable, and with a disc 45" wide there is plenty to see. But one of the good things about Jupiter (and, indeed, all the outer planets), is that its distance is so much greater than the variations brought by the Earth's orbital movements, that if you can see it at all, it will always be of comparable size and brightness. (The varying inclination of Saturn's rings make that planet a partial exception). Mars, on the other hand, varies from 26" to 3" (less than Uranus), and yet even when Mars is so poorly...

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