 This allows scientists to probe both the density of the interstellar medium and the energy of the accelerated electrons from the source.The result, with Caraveo as first author, was published in Science, on September 5, 2003 (which devoted its cover to XMM-Newton), and has received substantial coverage in the Italian and world press.Observations from Chandra also revealed a tail that follows the pulsar, perfectly aligned with its proper motion.