Washington: NASA`s Interstellar Boundary Explorer (IBEX) has for the first time mapped out the structure of our solar system`s tail, which is shaped like a four-leaf clover.
Scientists have described the tail, called the heliotail, based on the first three years of IBEX imagery.
While telescopes have spotted such tails around other stars, it has been difficult to see whether our star produced one.
While telescopes have spotted such tails around other stars, it has been difficult to see whether our star produced one.
The particles found in the tail-and throughout the entire heliosphere, the region of space influenced by our sun-do not shine, so they cannot be seen with conventional instruments.
"By examining the neutral atoms, IBEX has made the first observations of the heliotail ," David McComas, IBEX principal investigator at Southwest Research Institute in San Antonio, Texas, and the paper`s lead author, said.
IBEX measures the neutral particles created by collisions at the solar system`s boundaries.
By combining observations from the first three years of IBEX imagery, the team showed a tail with a combination of fast and slow moving particles.
There are two lobes of slower particles on the sides and faster particles above and below.
This four-leaf clover shape can be attributed to the fact that the sun has been sending out fast solar wind near its poles and slower wind near its equator for the last few years.
This is a common pattern in the most recent phase of the sun`s 11-year activity cycle.
The clover shape does not align perfectly with the solar system, however.
The entire shape is rotated slightly, indicating that as it moves further away from the sun and its magnetic influence, the charged particles begin to be nudged into a new orientation, aligning with the magnetic fields from the local galaxy.
Scientists do not know how long the tail is, but think that it eventually fades away and becomes indistinguishable from the rest of interstellar space.
The findings are published in the Astrophysical Journal.
ANI
