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

1242 Views

See similar Physics GCSE tutors

Related Physics GCSE answers

All answers ▸

Trolley A carrying mass 10kg is moving at speed 5m/s, and collides with stationary Trolley B carrying a mass 5kg. Indicating which Law you would apply, what is the speed and direction of Trolley B if Trolley A's resulting movement is 2m/s to the left?


What is terminal velocity and what causes it?


Why do Physicists take multiple readings in experiments?


Sophia (mass 47Kg) is travelling to the right with a velocity of 7.2m/s and ​Neesha (mass 68Kg) is travelling to the left with a velocity 4.8m/s. When ​they meet, they hold hands and travel off together. Give their final ​velocity and direction


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