Venus Transit Seen Reflected from the Moon

On 6 June 2012 Venus passed directly between the Earth and the Sun and the planet appeared as a silhouette against the solar disc. Such a transit of Venus will not happen again until 5 December 2117. The recent transit could not be seen from ESO’s Chile observatories as the Sun was below the horizon. But, undaunted, a team of Italian astronomers led by Paolo Molaro of the Instituto Nazionale di Astrofisica at the University of Trieste used the opportunity to perform an unusual and challenging experiment, looking at the sunlight reflected off the Moon to see how it changed during the transit. This measurement, done with ESO’s High Accuracy Radial Velocity Planet Searcher (HARPS) spectrograph installed on the ESO 3.6-metre telescope at La Silla in Chile, could help scientists to find planets in orbit around other stars. The team has published their results in the journal Monthly Notices of the Royal Astronomical Society.

More Information

The new work appears in, “Detection of the Rossiter–McLaughlin effect in the 2012 June 6 Venus transit”, P. Molaro, L. Monaco, M. Barbieri & S. Zaggia, to appear in the Monthly Notices of the Royal Astronomical Society: Letters.

Courtesy of European Southern Observatory