Press release


First observation of matter emitted from the Geminga pulsar

Paris,September 4, 2003


The Geminga pulsar, the neutron star nearest to the Earth, was recently observed by the XMM-Newton satellite. Scientists detected two very long, symmetrical tails, created by the bow shock of the matter emitted from the pulsar, which moves at supersonic speed. These findings were published in the September 5, 2003, issue of Science and are featured on the journal's cover.

The Geminga pulsar has been observed with the XMM-Newton telescope of the ESA by an international team(1) including researchers from the "Centre d’étude spatiale des rayonnements" (CESR - CNRS, Paul Sabatier University in Toulouse, Midi-Pyrénées Observatory). The observation data reveal the presence of two elongated, symmetrical tails of X-ray light stretching more than one-third of a light year. These are high-energy electrons confined by the interstellar shock magnetic field. These two visible tails are in fact the two edges of a cone created by the supersonic motion of Geminga in the interstellar medium.

The Geminga pulsar is a rapidly spinning neutron star. Geminga was observed for the first time 30 years ago by Giovanni Bignami, who gave the star its name. Geminga is a play on words in Milanese dialect that means "does not exist." It is one of the nearest pulsars, located at a distance of 500 light years from Earth.

1 - This international team is made up of P.A. Caraveo (CNRS-Italy), G.F. Bignami (CESR-CNRS), A. DeLuca (CNR-Italy), S. Mereghetti (CNR-Italy), A. Pellizzoni (CNR-Italy), R. Mignani (ESO), A. Tur (CESR-CNRS), W. Becker (MPE-Germany)


Researcher contact:
Giovanni Bignami, CESR
Tel: +33 5 61 55 85 86

INSU-CNRS Contact:
Philippe Chauvin
Tel: +33 1 44 96 43 36

CNRS press contact:
Martine Hasler
Tel: +33 1 44 96 46 35