Where in the world is the Voyager 1?

Despite an American Geophysical Union (AGU) report tipping the spacecraft's exit from the heliosphere, NASA is skeptical, saying that "it is the consensus of the Voyager science team that Voyager 1 has not yet left the solar system or reached interstellar space."

The AGU cited an Aug. 25 measurement that showed "drastic changes in radiation levels," an indication that Voyager 1 had left the heliosphere, or "the immense magnetic bubble containing our solar system, solar wind, and the entire solar magnetic field."

"Within just a few days, the heliospheric intensity of trapped radiation decreased, and the cosmic ray intensity went up as you would expect if it exited the heliosphere," Bill Webber, professor emeritus of astronomy at New Mexico State University in Las Cruces, said in a statement. He called the transition boundary the "heliocliff."

But Ed Stone, Voyager project scientist based at the California Institute of Technology, explained in a statement that the ship had simply reached a new region called "the magnetic highway," where energetic particles changed dramatically.

"A change in the direction of the magnetic field is the last critical indicator of reaching interstellar space," he said. "And that change of direction has not yet been observed."

Webber acknowledged that there's still an ongoing debate about the ship's location. "It's outside the normal heliosphere, I would say that," he said. "We're in a new region. And everything we're measuring is different and exciting."

AGU's findings were in its Geophysical Research Letters journal, where the authors definitively stated that "It appears that [Voyager 1] has exited the main solar modulation region, revealing [hydrogen] and [helium' spectra characteristic of those to be expected in the local interstellar medium."

In late 2010, NASA put the Voyager 1 10.8 billion miles from the Sun, and traveling at a rate of 38,000 miles per hour through the heliosphere. Another tip came in June, when Stone predicted the Voyager's locale somewhere in a new region "where things are changing more quickly," adding that "we are approaching the solar system's frontier."

The Voyager 1, launched on Sept. 5, 1977, was built at NASA's Jet Propulsion Laboratory (JPL) in California, where it continues to be managed and operated. PCMag's own Meredith Popolo visited the lab last year to watch what was later dubbed the "7 Minutes of Terror" as NASA's Curiosity rover landed on Mars. For more, check out the slideshow above for shots from her tour of JPL.

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