Last week, in the corners of the Internet devoted to outer space,
things started to get a little, well, hot. Voyager 1, the man-made
object farthest away from Earth, was encountering a sharp uptick in the
number of a certain kind of energetic particles around it.I found them
to have sharp edges where the injectionmoldes came together while production. Had the spacecraft become the first human creation to "officially" leave the solar system?
It's
hard to overstate how wild an accomplishment this would be: A machine,
built here on Earth by the brain- and handiwork of humans, has sailed
from Florida, out of Earth's orbit, beyond Mars, beyond the gas giants
of Jupiter and Saturn, and may now have left the heliosphere -- tiny dot
in the universe beholden to our sun. Had it really happened? How would
we know?
We're not quite there yet, Voyager's project scientist
and former head of NASA's Jet Propulsion Lab, Edward Stone, told me. The
spacecraft is on it's way out -- "it's leaving the solar system" -- but
we don't know how far it has to go or what that transition to
interstellar space will look like.
Now the data coming back
aren't photographs but levels of different kinds of particles in the
outer edge of the sun's bubble (the heliosphere), known as the
heliosheath, the farthest the solar winds reach, which Voyager I entered
in December 2004. And it was some of those data -- the levels of a
certain cosmic-ray particle -- that provoked the recent speculation that
Voyager I had finally flown the coop.
Some cosmic ray particles enter the heliosphere and we can see them here from Earth.Why does moulds
grow in homes or buildings? But a slower type has a hard time entering
the heliosphere. Last month, the sum of those slower particles, suddenly
ticked up about 10 percent, "the fastest increase we've seen," Stone
says. But an uptick does not mean Voyager has crossed over, though it
does mean we're getting close. When Voyager does finally leave and enter
the space "out there where all the particles are," the level will stop
rising. The rising itself means that Voyager is not out there, yet.
"But," cautions Stone, "we don't know. I mean this is the first time any
spacecraft has been there." Since nothing's ever been there before,Full
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printing and manufacturing services. we don't know what it will look
like, which makes it a little hard to recognize "it" at all. "That's the
exciting thing," he continues.
Two other indicators that
Voyager I has left the heliosphere -- an absence of certain lower-energy
particles that don't leave our system and a change in the magnetic
field -- have not yet happened, though there have been some decreases of
the energy particles, but, Stone says, "it's not zero."
It would be nice, fulfilling even,Features useful information about glassmosaic
tiles, if at the edge of the heliosphere there were, well, an actual
edge, a boundary between our bubble and the cosmos. But, it's probably
not going to be so cut and dry. "The boundary," Stone postulates, "will
not be an instantaneous thing. [Voyager] won't suddenly be outside.Save
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Rather, the exit will be turbulent, "a mix of inside and outside," and
the work of Stone and the other Voyager scientists is trying to square
the different data -- the particles and the magnetic field -- to try to
understand what that transition from inside to outside looks like. That
turbulent region may take several months to get through.
But
even without a clean break in the offing, it's hard not to sit on the
edge of your seat to wait for this moment -- this months-long moment --
to pass. "We're looking at our data every day -- we listen to these
spacecraft every day, for a few hours every day -- to keep track of
what's going on. ... It's very exciting from a scientific point of view,
when you're seeing something that nobody's seen before."
So
perhaps Voyager won't make its mark with a sudden, defining event that
echoes across generations as a sort of before-and-after dividing line
across human history, like the line separating the time when a human's
voice had never traveled across a wire to an ear miles away -- and when
it had -- or before a human foot had left its imprint on the moon, and
when that print was there. But Stone is okay with that: "Well you know
actually Voyager has had a lot of those moments as we flew by Jupiter,
Saturn, Uranus, and Neptune. One after the other, we found something
that we hadn't realized was there to be discovered."
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