Stellar Twins (IMAGE) University of Cambridge Caption 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 Usage Restrictions Please credit to Carolina Jofré License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.