How do the scientist the measure the distance of an object which are light years away?

Question

I came to know about J1470B which is 430 ly away from earth. How do scientists measure the distance. It can not be by light I guess because light itself takes 430 years to come to earth. So what is it? How do they measure?

In: 12

Answer 1

There are a few ways, but one is Parallax. Take very precise measurements from multiple points far distant from another and you can see subtle changes depending on your vantage point. Do math on those changes and you can determine how far away the object is