Image: Two ‘twin’ stars with identical spectra observed by the La Silla Telescope. Since it is known that one star is 40 parsecs away, the difference in their apparent brightnesses allows calculation of the second star’s distance. Credit: Carolina Jofré.
Astronomers from the University of Cambridge have developed a new, highly accurate method of measuring the distances between stars, which could be used to measure the size of the galaxy, enabling greater understanding of how it evolved.
Using a technique which searches out stellar ‘twins’, the researchers have been able to measure distances between stars with far greater precision than is possible using typical model-dependent methods. The technique could be a valuable complement to the Gaia satellite – which is creating a three-dimensional map of the sky over five years – and could aid in the understanding of fundamental astrophysical processes at work in the furthest reaches of our galaxy. Details of the new technique are published in the Monthly Notices of the Royal Astronomical Society.
“Determining distances is a key problem in astronomy, because unless we know how far away a star or group of stars is, it is impossible to know the size of the galaxy or understand ...