Voyager 1 and 2 say solar system is dented

William Atkins
Tuesday, 11 December 2007 19:19

Science - Space

The interstellar medium is composed of tiny amounts of gas and dust that fill up interstellar space (the space that fills up between stars and within galaxies). The energy in the interstellar medium is electromagnetic radiation and produces the interstellar magnetic field. The unevenness of the shape of the solar system is thus caused by the interstellar magnetic field that is pitched (slanted) at an angle to the plane of the Milky Way galaxy, of which the solar system is a member.

Scientists have assumed that the solar system was asymmetrical (they have called its shape as “bent” or “dented in places”) but before data came in from Voyager 1 and 2 they never had any direct evidence for its asymmetrical shape.

In fact Voyager project scientist Ed Stone, of the California Institute of Technology, Pasadena, California, said, "So there's something outside pushing in on the southern hemisphere of the heliosphere." He went on to say that it is “distorting a more or less spherical surface." [MSNBC]

Stone, who related this information at a recent meeting of the American Geophysical Union in San Francisco, California, went on to say that Voyager 1 will cross the shock wave (the termination shock) only once, however, Voyager 2 will cross it many times due to its waviness. Stone compares it to the surf on a beach.

Voyager 1 and 2 are expected to remain functioning well into the 2020s, so will hopefully be able to tell scientists back here on Earth when they finally leave the solar system.

The NASA Jet Propulsion Laboratory website for Voyager 1 and 2 is: http://voyager.jpl.nasa.gov/.