Describe one method by which the distance to stars from Earth is measured, and one modern improvement to this method which increases its accuracy.

One such method is Stellar parallax. When observing stars in the night sky, stars which are further away from Earth appear to 'move' less across the sky as the earth rotates. Using this, stellar parallax works by observing the position of the target star (the one you are calculating the distance of) relative to a star (or stars) 'behind' it. After 6 months, one half-orbit around the Sun, observe the target star's position relative to these distant stars again and measure the angle subtended by Earth to this star. This angle should be in arc seconds. The distance of the target star is given, in parsecs, by d=1/p. A recent improvement of this method is the ability to position telescopes in Earth's orbit (such as the Hubble Space Telescope), which removes any adverse effects of the Earth's atmosphere.

Answered by Harry H. Physics tutor

1244 Views

See similar Physics GCSE tutors

Related Physics GCSE answers

All answers ▸

What is the difference between a vector and a scalar quantity?


If a boy is stationary on a skateboard and jumps off forwards, why does the skateboard move backwards?


If Newton's third law is correct, why are walls not indestructible? In applying a force to a wall, if it breaks surely it is not giving an equal and opposite force.


Give three properties that are the same for radio waves and microwaves


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo
Cookie Preferences