How do you measure stuff in space? How do we know this star weighs x-times the weight of the sun? And how we know how much the sun weights. Same goes for distances. How can you tell how far something is?

Question

How do you measure stuff in space? How do we know this star weighs x-times the weight of the sun? And how we know how much the sun weights. Same goes for distances. How can you tell how far something is?

In: Physics

Answer 1

For measuring distance in space, you use Parallax. You measure on opposite sides of the sun, so once in December, and then once in June. You’ll use the known 1 au (93,000,000 miles). and figure the tangent by using the arcseconds of change in the night sky.

As for measuring mass, the most common method is gravitational lensing. By careful measurements you can figure out how much light is bent when traveling near an object, and use that to figure out the mass.

I realize its not really explaining it like you’re 5, but the questions really aren’t answerable in a way that doesn’t use complex mathematics.