Por si a alguien le interesa, ayer hicieron un AMA en reddit los responsables del proyecto Voyager. Contestaron entre otras cosas a esa duda que tenéis sobre dónde acaba el sistema solar y dónde empieza el espacio exterior.
http://www.reddit.com/r/IAmA/comments/1m9wke/were_scientists_and_engineers_on_nasas_voyager/
Q: I'm curious as to what establishes the distinction between Interstellar space and space considered to belong to our Solar system. In other words, what boundary was crossed that you can tell that V'Ger is now in Interstellar space, where previously it was not.
A: Matt Hill: This is not at all obvious...we're still trying to work this out ourselves. We are currently going with the particle and plasma based definition. Voyager 1 is currently surrounded by particles that came from other stars, not from our sun. Before it crossed it was surrounded by material from the sun. Other definitions have included requirements on changes in magnetic field orientation.
Q: Are you aware that, despite no where in the official press release talking about 'leaving the solar system', that that is still the headline for CNN, BBC, and a host of other prominent outlets? It obviously should be, "Voyager now in interstellar space." Do you plan to address the difference between the two? Because it appears the media sure doesn't know.
A: It's a very fine point and many people don't realize the Oort cloud is in interstellar space AND it's considered part of the solar system. We knew many media would make the error and we tried to make it clear in interviews. And you're right -- none of our materials say we've exited the solar system. Thankfully, some media have recognized the distinction. Mashable.com has a good story that explained the difference. http://mashable.com/2013/09/12/voyager-1-interstellar-space/ It's actually a cool factoid that the public could learn about our solar system. @VeronicaMcg Social Media Team