Sunday, October 18, 2009

NASA’s IBEX (or Interstellar Boundary Explorer) satellite, released into orbit last October, has provided the data for the first “all sky map” showing the boundary between the Solar System and Interstellar Space. IBEX mapped the sky using two sensors, gathering information about the particle structure within the Milky Way. This map should help researchers better understand relationships between the Sun and our Galaxy.

The particles which IBEX looks for are energetic neutral atoms, atoms with a neutral charge that release large amounts of energy in most directions. The best place to find these particles is in the Sun’s Heliosphere, where forces from outside our solar system interact with the Sun’s magnetic field, causing these particles to become highly energetic. Two sensors on IBEX detect and catalog this. After six months of repeating this cycle over the entire night sky, IBEX acquired enough data to create the all sky map.

This map goes beyond the capacities of the Voyager missions, giving an insight into the Sun’s interaction with the rest of the galaxy. As Cosmic rays approach the solar system, the heliosphere prevents them from crossing into the heart of the solar system, thereby effectively stopping these harmful rays from reaching Earth. This new energy is released from electrically neutral atoms, and when scientists look at the energy given off by these atoms they have a general view of what energy is coming from what area.

Knowing the place in the galaxy where certain rays come from help scientists understand the way our galaxy functions, from star positioning to globular clusters. “For the first time, we’re sticking our heads out of the sun’s atmosphere and beginning to really understand our place in the galaxy,” said David J. Comas of NASA.