Using the ESO 3.6 metre telescope to test for variations in the fine structure constant among nearby solar twins

In lieu of a regular AAL ESO Blog post, we encourage our community to read the article that appeared recently in The Conversation by Prof. Michael Murphy from Swinburne University of Technology. In this article Michael (who is also Australia’s observer on the ESO Scientific Technical Committee) describes how he and colleagues from Swinburne and UNSW compared archival spectra of 16 stars quite similar to the Sun (“solar twins”) taken with the HARPS instrument on the ESO 3.6 metre telescope at La Silla. In a paper recently published in the prestigious journal Science, they conclude that the fine structure constant α that defines the strength of the electromagnetic force varies by no more than 50 parts in a billion between all these stars within 50 parsecs of our Sun.