Let's argue that point
Not you Sean, I'm having a go at NASA.
Hands up who believes Voyager has entered interstellar space?
I think they need to come up with a better term of where it is, after all, it's still under the sun's gravitational influence so I don't see how this can be classed as interstellar space.
.
I much prefer the way Fred Watson described on tv today.
Anyway, I'll pop here my facebook post that I did just earlier for the IceInSpace page as it's got some terrific links including the Fred Watson interview.....
It's for real this time. Yesterday, the 12th of September, 2013 NASA announced the news with the headline: "NASA Spacecraft Embarks on Historic Journey Into Interstellar Space".
Looking back at their data over the last year has revealed that this event took place in August 2012.
Professor Fred Watson was on ABC1's "Midday Report" today giving an interview on it. I have to admit, I much prefer his description: "Voyager 1 spacecraft has left the solar system, crossing the boundary between the solar system and interstellar space."
It can be viewed here (perhaps only viewable in Australia):
http://www.abc.net.au/iview/#/search/midday%20report
Let's make something clear here though as I can see much confusion arising- it still has NOT left the Sun's gravitational influence.
From NASA's article, "How Do We Know When Voyager Has Entered Interstellar Space":
"Stone called three meetings of the Voyager team. They had to decide how to define the boundary between our solar bubble and interstellar space and how to interpret all the data Voyager 1 had been sending back. There was general agreement Voyager 1 was seeing interstellar plasma, based on the results from Gurnett and Kurth, but the sun still had influence. One persisting sign of solar influence, for example, was the detection of outside particles hitting Voyager from some directions more than others. In interstellar space, these particles would be expected to hit Voyager uniformly from all directions."
Read More:
http://1.usa.gov/188Trvn
"Voyager 1 does not have a working plasma sensor, so scientists needed a different way to measure the spacecraft's plasma environment to make a definitive determination of its location. A coronal mass ejection, or a massive burst of solar wind and magnetic fields, that erupted from the sun in March 2012 provided scientists the data they needed. When this unexpected gift from the sun eventually arrived at Voyager 1's location 13 months later, in April 2013, the plasma around the spacecraft began to vibrate like a violin string. On April 9, Voyager 1's plasma wave instrument detected the movement. The pitch of the oscillations helped scientists determine the density of the plasma. The particular oscillations meant the spacecraft was bathed in plasma more than 40 times denser than what they had encountered in the outer layer of the heliosphere. Density of this sort is to be expected in interstellar space.
The plasma wave science team reviewed its data and found an earlier, fainter set of oscillations in October and November 2012. Through extrapolation of measured plasma densities from both events, the team determined Voyager 1 first entered interstellar space in August 2012.
"We literally jumped out of our seats when we saw these oscillations in our data -- they showed us the spacecraft was in an entirely new region, comparable to what was expected in interstellar space, and totally different than in the solar bubble," Gurnett said. "Clearly we had passed through the heliopause, which is the long-hypothesized boundary between the solar plasma and the interstellar plasma."
The new plasma data suggested a timeframe consistent with abrupt, durable changes in the density of energetic particles that were first detected on Aug. 25, 2012. The Voyager team generally accepts this date as the date of interstellar arrival. The charged particle and plasma changes were what would have been expected during a crossing of the heliopause."
Read More:
http://1.usa.gov/17uWBwu
If you want more information, Sydney Morning Herald also did a very good article this morning (a great little video included) which can be viewed here:
http://bit.ly/15o4y77
Voyager 1 is expected to keep sending back data - with a 23-watt transmitter, about the equivalent of a refrigerator light bulb - until roughly 2025.
