Star trails reflect Earth's rotation, or spin, around its axis. The Earth makes a complete rotation relative to the backdrop stars in a period of about 23 hours and 56 minutes.Facing south during April and May the pre-dawn hours are best. From June to early August the best time is near midnight, though the Milky Way will be visible almost all night. From Mid August through September the best time is soon after the sun has set and the sky has grown dark.
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