October 17, 2026 · 8 min
Measuring the distance to a star
Look at a star in January and again in July, and it shifts a tiny amount. That shift is a distance.
Free
Because
A short letter every Sunday: one discovery about the sky, and the steps that led to it.
2,800 readers
Free, and you can leave any time
More posts
The stars that blink like lighthouses
A careful count of stars that brighten and fade gave us a ruler for the far sky.
What the stars are made of
Once the dark lines in sunlight were matched to flames in a lab, the stars could be read like a label.