Sun Drags Space Junk Out of Earth Orbit

Generally, solar flares are bad news for stuff orbiting the Earth. The impact of intense solar radiation on sensitive electronics can render the most sophisticated space technologies useless. Also, heating and expansion of the Earth's upper atmosphere by peaking solar activity can increase drag on satellites, slowing them down, causing them to drop from orbit.
How could this negative situation be turned into a positive? What's bad for operational satellites has the wonderful side effect of helping mankind with an increasingly pressing problem: the specter of space junk.

he same thing that threatens the safety of multi-million dollar satellite systems may be helping to "scrub" space trash from orbit. During periods of increased solar activity -- like now -- the sun turns into a passive vacuum cleaner of sorts. As magnetic activity inside the sun amps-up toward peak activity in its 11-year solar cycle (known as solar maximum, predicted to occur in 2013), there is a higher frequency of solar flares and coronal mass ejections (CMEs). This increased energy output energizes the outer layers of the Earth's atmosphere, and through the laws of basic thermodynamics, it causes the atmosphere to expand.
This expansion pushes some of the gas to higher altitudes. It's like a speeding car hitting a sand-filled escape lane -- the drag of the loose sand zaps the forward momentum of the car, bringing it to a stop. Back in orbit, this tenuous gas creates drag on orbiting space debris, causing it to slow down.
(Spacecraft sent to other planets -- such as the Mars satellites -- use this high altitude atmospheric drag to slow them down just before orbital insertion, a maneuver called "aerobreaking.")
As the debris slows, Earth's gravity pulls it to lower altitudes where the atmosphere is even thicker. Thicker atmosphere = more drag = slower debris. Eventually the debris reenters the atmosphere sooner than it would do without the solar influence, burning up safely (for the most part).

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