Electrons in a Helium Atom (IMAGE) Max-Planck-Gesellschaft Caption Electronic pas de deux: physicists in Heidelberg have filmed the pulsing motion of the electron pair in a helium atom. At 15.3 femtoseconds (fs) the two electrons are close to the nucleus (center of image) and then move away from it. The color indicates the probability of finding one electron at position A (vertical axis) and the second electron at position B (horizontal axis) on a line drawn through the atom (along the polarization direction of the laser). At 16.3 femtoseconds they arrive back at their original position again; they thus move with a beat of around one femtosecond. Credit MPI for Nuclear Physics Usage Restrictions Use of images is limited to editorial coverage of scientific topics relating to the activities of the Max Planck Society. Any kind of commercial use (including, in particular, the exploitation of images by means of sale or incorporation in image databases or image catalogues) as well as any promotional use/use for merchandise purposes, disclosure to third parties or granting of related rights to third parties is expressly not permitted. 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.