NASA's IBEX maps solar system's tail for the first time

“An earlier analysis made the tail looked much smaller. We’ve realized that the original tail was just a fraction of a much larger structure,” said Dr. McComas.

The researchers are using seafaring terms to distinguish the lobes, only two of which are pictured in the visualization. One lobe is called the port and the other the starboard. In that analogy, the heliosphere is referred to as the vessel, ferrying the solar system through the galaxy.

To visualize the tail, picture a globe rendered two dimensionally. The side of the globe we are looking at is the downwind side. The opposite side is the upwind side. It is unknown exactly how much distance is between the two - in other words, how long the tail is.

"The tail's end is somewhat ambiguous," said Eric Christian, IBEX mission scientist at NASA’s Goddard Space Flight Center, noting that is estimated to be about 100 billion miles long.

The port side of our 2-dimensional globe, some 10 billion miles wide, is to the east, and the starboard side is to the west. The low-latitudes of the globe are filled with slow moving particles, and the fast moving particles are at the northern and southern most end of the visualization. That's because fast-moving particles tend to originate from the sun's poles.

The globe, not quite symmetrical, is tilted to put the port side somewhat higher than the starboard side. That comes from the heliosphere’s interaction with the interstellar magnetic fields as it moves – the magnetic field exerts a force on the tail, flattening it and somewhat twisting it.

Dr. Christian told the Monitor that IBEX researchers are next looking to understand how time influences the heliotail, since the sun’s behavior changes in an 11 year cycle. The data received is from the sun during its quiet phase, and the particles blown out during the sun's current active phase will take some 3-5 years to reach IBEX, he said.

Much is unknown about the outer edge of our solar system. Researchers are still waiting for Voyager 1, launched some 35 years ago and now more than 11 billion miles afield from the sun, to leave the heliosphere for interstellar space.

In June, the spacecraft identified a previously unknown space region called the magnetic highway, or the depletion region. Scientists are hoping – but still unsure – that this is the region directly abutting the heliopause and is the final area through which Voyager 1 must pass to exit the solar system.

"We're still understanding our own solar system," said Dr. Christian. "These thing are close, on relative scale, but we don’t know anything about them."

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