Closure of Great Equatorial Dome and Time for Navy Gallery

The Great Equatorial Dome and the Time for Navy Gallery will be closed between 11:30am and 3.45pm on Tuesdays, Wednesdays and Thursdays from 25 July to 24 August for Daytime sky watch sessions 

Planetarium closures

Visiting the planetarium? Our planetarium is open daily, 10am-5pm. It is closed for maintenance on the first Tuesday of every month from September 2017. See what's on and choose your next space adventure

Essential information

Key stage: 
Key Stage 4
Resource type: 
Classroom activity
Video
Location: 
Royal Observatory
School subject: 
Astronomy, Maths, Science

This video explains how we can measure the distance to near and far objects in the universe using parallax, 'standard candles' and the Doppler effect.

In the accompanying activity, students use the parallax formula to calculate the distances to stars in Orion.