Hipparcos

Imagine you have a giant ruler that you can use to measure distances to faraway stars. That's sort of what Hipparcos did for scientists.

Hipparcos was a really cool mission that sent a special telescope called a satellite into space to measure the distances from Earth to stars. The telescope is kind of like a really big magnifying glass that lets scientists see really far away things in space.

Now, you might be wondering why it's important to know how far away stars are. Well, knowing the distance to a star can help scientists figure out how big it is, how bright it is, and even how old it is! Scientists can learn a lot about stars just by knowing how far away they are.

So, Hipparcos was designed to measure these distances really accurately. It did this by watching the stars over a period of time and seeing how they moved in the sky. By measuring the angles of the stars from different parts of the Earth's orbit, scientists could calculate how far away they were.

Hipparcos was a huge success! It helped scientists measure the distances to thousands of stars and gave us a much better understanding of the universe. Thanks to Hipparcos, we now know that our galaxy (which is like a big city of stars) is even bigger than we thought!