For at least a year now, NASA has been waiting with bated breath for Voyager 1 to pass through the boundary of our solar system and become our first emissary to the stars. It’s been cruising the edge for some time, but when it finally leaves forever, it won’t be a satisfyingly clear punch-through — so it’s hard to say exactly when this will happen. Or happened. Now the spacecraft is in another strange new zone, where the influx of cosmic particles has been ramping up by the week.
A small Earth-orbiting probe has sampled the interstellar wind for the first time, detecting four types of atoms that originated in distant stars and traveled across the universe. The new measurements from the Interstellar Boundary Explorer give astronomers a glimpse of the cosmos outside our sun’s sphere of influence, and provide some clues about how and where our solar system formed.
Our sun has been more active lately as it enters a new phase in its 11-year cycle, which is one reason we've seen a bunch of enormous coronal mass ejections and solar explosions in the past few months.
The Voyager 1 spacecraft might be crossing the interstellar boundary at the edge of our solar system much sooner than scientists thought, according to new data from the probe itself and from the Cassini spacecraft. This milestone — marking the first Earth-born object ever to leave the sun’s field of influence — could actually happen any day now. According to scientists' best estimates, it will happen by the end of 2012.
For decades, scientists have believed there to be a fairly well-defined boundary at the edges of our solar system, a region where the sun appears only slightly brighter than the rest of the spangled heavens. But as they sail through the blackness, humanity’s most-traveled spacecraft, the Voyager probes, have learned the lines are anything but clear. The edge of the solar system may not be a smooth edge at all, but a turbulent moat of roiling magnetic bubbles.
NASA’s Voyager 1 spacecraft, now in its 33rd year on the job, has reached the very edge of our solar system and is nearing the cusp of interstellar space. How does NASA know? The wind has died down. Voyager 1 has reached a point in the heliosheath that envelopes our solar system in which the speed of the solar wind that has been at Voyager’s back for three decades has dropped to zero.
Lost galactic hitchhikers can now rejoice when they visit our corner of the Milky Way. A new sky map created by a NASA spacecraft shows the boundaries of our solar system in comparison to the rest of the interstellar neighborhood.
The boundaries are defined by our sun's heliosphere -- a protective bubble created by the solar wind that travels outward and collides with incoming interstellar radiation. That typically invisible boundary became visible through energetic neutral atoms created in the region that speed toward the sun at velocities ranging up to 2.4 million mph.