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发帖数: 1994 | 1 Mercury Over Leeds
Credit & Copyright: Tony Cook
Explanation: Have you ever seen the planet Mercury? This week might
be a good time. Because Mercury orbits so close to the Sun, it never
wanders far from the Sun in Earth's sky. If trailing the Sun, Mercury
will be visible low on the horizon for only a short while after sunset.
If leading the Sun, Mercury will be visible only shortly before sunrise.
So at certain times of the year an informed skygazer with a little
determination can usually pick M |
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