Describe how you measure the parallax between the earth and a star?

Question

I need help quick

Answer 1

Parallax is an effect that we have in front of our eyes every day.Most of us take it for granted.
Paralax is a way to estimate distance unsing a trigonometric procedure called "triangulation".
If we know one side of a right triangle and one angle ,we can calculate the longer side of the triangle.
In the case of the earth a triangle can be formed by observing a fixed star angle relative to a point on Earth and measure the same angle on the opposite side of the earth.Applying simple trig formula the distance to the observed star can be calculated.

Note the further away a star is located the smaler the Angle(paralax). the biggest distance that can be measured by use of telescope would have a parallax of one second of arc.
Any greater distance than that ,the radiation spectrum shift of light is used to measure distances to stars or galaxies.

Answer 2

Hi. First you need a reference, usually the background galaxies, from which to discern apparent movement. Then you look at the position once today and once in six months when the Earth is on the other side of its orbit. This is what gets measured, the apparent motion.