Скачать или смотреть The "Thumb Trick" That Measures The Distance between Stars

How do you measure the distance to a star that's trillions of miles away? You can't use a ruler, and you can't bounce a laser off it.

The answer is surprisingly simple and brilliant: you use trigonometry.

This is the method of Stellar Parallax, and it uses the largest "ruler" we have: the entire orbit of the Earth.

Here’s how it works:

In January, an astronomer takes a picture of a nearby star, noting its position against the "fixed" background of very distant galaxies.
Then, they wait six months.

In July, when Earth is on the other side of the Sun (186 million miles, or 300 million km, from where it was), they take another picture of the same star.

From this new vantage point, the nearby star will appear to have shifted or "wobbled" slightly. It's the same illusion you see when you hold your thumb out and blink, switching from your left eye to your right.

By measuring that tiny, tiny angle of the "wobble," and knowing the length of their baseline (186 million miles), astronomers can solve the triangle and calculate the star's distance. It's the first and most fundamental step on our cosmic distance ladder.

✨ Isn't it amazing that we can map the galaxy just by waiting 6 months? Let me know your thoughts! 👇

#universia #nasa #parallax #space #astronomy #science #trigonometry #deepspace #spacefacts #cosmology