Mystery #2Tier 2measuring the stars

How do astronomers measure how far away a star is when it is impossibly far?

The nearest star beyond our own Sun is so far that its light takes years to reach us. You cannot stretch a tape measure across empty space. You cannot pace it out with your feet. So how on Earth does anyone work out just how far away a star really is?

The Milky Way arching over a dark forest clearing, thousands of stars scattered across the sky with no clue as to which are near and which are far — Photo: BLM Oregon & Washington · Public domain · via Wikimedia Commons

Your guess

What is your idea: how could we measure the distance to something we can never reach?

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