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With the Moon's terminator moving almost 10 mph (16 km/h) across its equator, how long would it take for an observer using binoculars to notice a change in lunar features?

Gary Garchar, San Jose, California
RELATED TOPICS: MOON
Moon's terminator
The lunar terminator, the sunset/sunrise line that sweeps across the Moon’s surface as the Moon orbits Earth, travels at a rate of 9.6 mph (15.4 km/h) along our satellite’s equator. Taking the average Earth-Moon distance to be 239,000 miles (384,600km), those miles translate to an angular shift of just over 8 arcseconds per hour.

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