Voyager 1 Confirmed to have Left Solar System Last Summer, New Reasearch Shows

originally posted by: wildespace
So the hypothetical Oort cloud is located in the interstellar medium, as opposed to being part of the Solar System? I don't consider the Voyager to have left the Solar System until it passes through the Oort cloud.

Voyager is in interstellar space -- not "outside the solar system".

But then again, "interstellar space" is just a term with a made-up definition (not exactly an arbitrary definition, but a definition controlled by the humans who invented it), so it is what it is.

a reply to: Soylent Green Is People

I think the media and (unfortunately) scientists are placing undue emphasis on such tag-phrases like "left the Solar System" and "entered interstellar medium", as if they are commenting about a sports event or an expedition into a dangerous region.

The Voyager is still in the Solar System, if we are to include the Oort cloud, and like you said the "interstellar medium" is a vague term. Rather, it would be more appropriate to concentrate on the actual milestones, such as various "layers" of space around the Sun.

originally posted by: wildespace
a reply to: Soylent Green Is People

I think the media and (unfortunately) scientists are placing undue emphasis on such tag-phrases like "left the Solar System" and "entered interstellar medium", as if they are commenting about a sports event or an expedition into a dangerous region.

The Voyager is still in the Solar System, if we are to include the Oort cloud, and like you said the "interstellar medium" is a vague term. Rather, it would be more appropriate to concentrate on the actual milestones, such as various "layers" of space around the Sun.

The Oort Cloud is not really considered part of the Solar System. The Kuiper Belt, yes but the Oort Cloud is considered interstellar space.

It's more like the left over debris from the stellar nursery that the Solar System was born from which became gravitationally bound to it combined with other stuff picked up along the way as the solar system moves in a circular orbit around the Milky Way galaxy.

The Oort Cloud is a massive spherical cloud; the size of this cloud is disputed by different astronomers. Some believe that it begins at 2000 or 5000 astronomical units–an astronomical unit (AU) equals the distance between the Earth and the Sun–and ends at 50,000 AU, which is almost a light-year. Others think that it may extend to over 100,000 AU, which would mean its edge would extend to nearly the end of the Solar System.

More here: solarsystem.nasa.gov...

a reply to: JadeStar

Interesting, I have never seen the notion that the Oort cloud is not part of the Solar System before. As far as I'm aware, it's part of the outer Solar System, and is gravitationally bound to the Sun. Wikipedia states, "The outer limit of the Oort cloud defines the cosmographical boundary of the Solar System and the region of the Sun's gravitational dominance."

Your quote from www.universetoday.com...: "Others think that it may extend to over 100,000 AU, which would mean its edge would extend to nearly the end of the Solar System."

But seeing how this is all hypothetical and tenuous, we might be merely arguing semantics.

I have also never come across the notion of the Solar System picking stuff up as it moves through the Milky Way (although I can imagine that some comets may originate from other systems).

Could you please link any relevant material about the Oort cloud not being considered part of the Solar System, and about the Solar System picking stuff up on its way through the galaxy?

P.S. Interesting factoid: Sedna, with its aphelion of 937 AU, crosses well beyond the heliopause (which only extends to about 200 AU maximum), meaning that, in the same terms as are applied to the Voyager, it leaves the Solar System and enters the interstellar medium on a regular basis. At 128 AU from the Sun, the Voyager 1 is well within Sedna's orbit, and hasn't even reached Sedna's semi-major axis (its average distance from the Sun).

So, to me at least, there are more reasons to conclude that the Voyager is still deep within the Solar System, than to regard it to have left it.

a reply to: wildespace
P.S. Not being a native English speaker, I used the wrong word, "factoid". I thought it meant a little and curious fact, but have since learned that it means something else. Oops!

originally posted by: wildespace
So the hypothetical Oort cloud is located in the interstellar medium, as opposed to being part of the Solar System? I don't consider the Voyager to have left the Solar System until it passes through the Oort cloud.

the Oort cloud consists mostly of stuff that got expelled when the local group of stars were forming their planetary systems and stuff that got expelled later. so the Oort clouds actually intermingle. also the Oort cloud can have cold Y type brown dwarfs and orphan planets as well as orphan dwarf planets and asteroids of various sizes as well as comets.

understanding the Oort cloud is important to interstellar travel planning because of the impact hazard and possible in situ resources for resupply. also for proper exploitation and exploration even before we can go interstellar.

imagine we find a terrestrial class planet out in the Oort but near enough we could probe it or even consider a manned expedition to it? potentially we could find frozen alien life.

the inner boundary of the Oort cloud or even it's very existence are disputed. some say it might begin as close as .25 LY out or as far out as 1 LY. i kind of hope it is the closer estimate. it would give us a reason to push out into interstellar space even with slow propulsion methods that we have already or are within a decade of creating.

Since Nasa in the beginning claimed that voyager WILL change magnetic field direction, when voyager moves out solar system, something that didnt happened yet.... Since NASA later on, announced that voyager moved out solar system (1 year ago), but it didnt changed magnetic field direction - they canceled themselves from the original statement... And now they claim, that voyager moved out but it actually didnt and it will move out in 30.000 years... Interesting.
Nasa doesn't know how much is 1+1, what about what is beyond...

The only interesting part in the whole thing is
1) magnetic field direction havent changed
2) the density of the plasma increasing

Maybe thats why 1 year ago, NASA claimed gizadeathstar.com...

and 1 week after that statement, they said : it moved out

originally posted by: MDDoxs
reply to post by Soylent Green Is People

 

In any case, I hope it doesn't return to earth like in the star trek film. Err actually I hope it does! I am off to watch the movie now!

Science fiction is the precursor of future events. I would not be surprised that V-ger returns.....