First sky maps from IBEX

IBEX, the Interstellar Boundary Explorer, studies the boundary between the heliosphere and the interstellar medium by observing energetic neutral atoms created as the solar wind hits interstellar gas. They have just released the first scientific results and associated sky maps from the data collected by IBEX. There’s a surprise within the results: IBEX observed a ribbon around the heliosphere that is a dense source of energetic neutral atoms, something that was completely unpredicted by any of the theoretical models. There also seems to be fine structure within the ribbon, something else completely unpredicted and suggesting something weird is going on in the boundary between the heliosphere and the interstellar medium.

It is still unknown what the ribbon is, but the fact that it is suspiciously aligned with the local galactic magnetic field might be a hint. And it does not seem to be a screwup with IBEX or due to a local source of energetic neutral atoms: the data from IBEX roughly agrees with observations made by Cassini’s Ion and Neutral Camera, which was primarily used to study Saturn’s magnetosphere but also captured data about the heliosphere.

Energetic neutral atom flux painted on heliopause

For a whole lot more details, here is the forty-minute press conference about IBEX: