v1la

Voyager 1 May Have Left the Solar System

8 Oct , 2012 by

Number of particles from the Sun hitting Voyager 1. Credit: NASA

While there’s no official word from NASA on this, the buzz around the blogosphere is that Voyager 1 has left the Solar System. The evidence comes from this graph, above, which shows the number of particles, mainly protons, from the Sun hitting Voyager 1 across time. A huge drop at the end of August hints that Voyager 1 may now be in interstellar space. The last we heard from the Voyager team was early August, and they indicated that on July 28, the level of lower-energy particles originating from inside our Solar System dropped by half. However, in three days, the levels had recovered to near their previous levels. But then the bottom dropped out at the end of August.

The Voyager team has said they have been seeing two of three key signs of changes expected to occur at the boundary of interstellar space. In addition to the drop in particles from the Sun, they’ve also seen a jump in the level of high-energy cosmic rays originating from outside our Solar System.

The third key sign would be the direction of the magnetic field. No word on that yet, but scientists are eagerly analyzing the data to see whether that has, indeed, changed direction. Scientists expect that all three of these signs will have changed when Voyager 1 has crossed into interstellar space.

“These are thrilling times for the Voyager team as we try to understand the quickening pace of changes as Voyager 1 approaches the edge of interstellar space,” said Edward Stone, the Voyager project scientist for the entire mission, who was quoted in early August. “We are certainly in a new region at the edge of the solar system where things are changing rapidly. But we are not yet able to say that Voyager 1 has entered interstellar space.”

Stone added that the data are changing in ways that the team didn’t expect, “but Voyager has always surprised us with new discoveries.”

Voyager 1 launched on Sept. 5, 1977, is approximately 18 billion kilometers (11 billion miles) from the Sun. Voyager 2, which launched on Aug. 20, 1977, is close behind, at 15 billion km (9.3 billion miles) from the Sun.

Sources: NASA, Eric Berger/ Houston Chronicle, Scientific American

, ,



Sort by:   newest | oldest | most voted
kkt
Member
kkt
October 8, 2012 11:11 PM

Godspeed, Voyager!

Kevin Frushour
Guest
October 8, 2012 11:17 PM

ELVIS HAS LEFT THE BUILDING!

???????? ????????????
Guest
October 9, 2012 12:24 AM

I can’t beleive it! Is it true yet? Wish Carl Sagan was here to comment on this!

MVJ
Guest
MVJ
October 9, 2012 3:05 AM

That’s the first time I’ve seen a distance of 3 billion km described as “close”.

Gozlemci
Member
October 9, 2012 4:17 AM

It may depend on the definition : “The boundry of the Solar System”; before Oort or after it !

Kevin Frushour
Guest
October 9, 2012 5:01 AM

I’m assuming the come-and-go pattern we’ve been seeing are fluctuations of the heliosphere as it passes to and fro over Voyager.

Queequeg de la Pequod
Guest
Queequeg de la Pequod
October 9, 2012 4:44 PM

The last I knew, the Oort is theory. There aren’t enough icy body trajectories for mathematical proof yet. Let’s keep holding our breath because the idea of our sun’s gravitational influence out to one light year is, what did Carl say, “Extraordinary claims require extraordinary evidence”.

Torbjorn Larsson OM
Member
Torbjorn Larsson OM
October 9, 2012 8:11 PM

Maybe it is a language issue, but the mathematical methods on theories (and observations) are statistical hypothesis testing. The only way the Oort cloud won’t remain a future theory is if it fails a test.

The larger issue then is if the Oort cloud is well tested or not. It is the simplest source for long-period comets. The immediate issue is if it is the consensus, and that it is.

As for gravitational influence, in itself it is not an extraordinary prediction in the same sense that the long-period comet source is not. (Eg they are the simplest predictions.) Sagan’s comment is entirely misplaced here.

Torbjorn Larsson OM
Member
Torbjorn Larsson OM
October 9, 2012 9:18 AM

The consistent solar wind drop all the way looks convincing enough for me.

Mike Lorrey
Guest
October 9, 2012 6:24 PM

So, when do we get the invitation to join the galactic federation?

krenshala
Guest
krenshala
October 9, 2012 7:22 PM

My understanding is that we have to drop off a form at the office near Proxima. wink

ITSki
Guest
ITSki
October 9, 2012 3:48 PM

Actually, I think that you have to mail the form in. If the reply from the federation is in your mailbox by the time that you get home from mailing the form, then congratulations, you’re a member.

magnus.nyborg
Guest
magnus.nyborg
October 9, 2012 6:54 PM

Bye Bye Birdie

wpDiscuz