Voyager approaches boundary of the Solar System

[Incognito]

I'm a great fan of the Voyager project - I personally consider it to be the leading modern wonder of scientific and technical development by humanity.

And now, still working after nearly 30 years, the Voyagers are closing on the boundary of the Solar System itself - where the Sun's influence fades and interstellar space itself is encountered. Truly exciting stuff - even overtaken the Pioneers.

Here's something from the New Scientist site:

http://www.newscientist.com/news/news.jsp?id=ns99994354

excerpt:

Voyager says goodbye to Solar System

The most distant man-made object - the Voyager 1 spacecraft - is finally leaving the Solar System. Astronomers think the probe has reached a boundary where the Sun's influence starts to wane.

The spacecraft has just entered a region no one has ever explored before, according to Voyager project scientist Edward Stone, at the California Institute of Technology in Pasadena. "This is a very exciting time," he told a NASA news conference in Washington DC. "Voyager is beginning to explore the final frontier of the Solar System."

Voyager 1 and its companion Voyager 2 were launched on a journey to the outer planets in 1977. Voyager 1 is now about 90 astronomical units from the Sun (one AU is the distance between the Earth and the Sun). It is the most distant spacecraft in the Solar System, having overtaken the Jupiter probe Pioneer 10 in 1998. Voyager 2 lags behind, at about 73 AU (see graphic).

For years, scientists thought Voyager 1 must be getting close to the Solar System's "termination shock". This is the region where supersonic particles streaming out from the Sun plough into interstellar particles and slow down to subsonic speeds. This region, often considered to mark the Solar System's edge, should energise lots of particles and have a strong magnetic field.

...

Around 2020, Voyager 1 is expected to reach the heliopause at roughly 135 AU. This is where the Sun's influence fades away entirely and interstellar space begins. Astronomers will then get their first chance to measure the magnetic fields and energetic particles of interstellar space.

And from the BBC website:

http://news.bbc.co.uk/1/hi/sci/tech/3245677.stm

excerpt:

Scientists say the Voyager 1 spacecraft is near the outer limit of the Solar System, 26 years after its US launch.


The boundary is a region called "termination shock" where particles from the Sun begin to slow down and clash with atomic matter from deep space.

Nasa says Voyager 1 is about 13.5bn kilometres from Earth and will not reach another system for 40,000 years.

The spacecraft carries greetings in 55 languages and audiovisual materials depicting life on Earth.




Beyond the ever-shifting termination shock boundary, lies a region called the heliopause, that marks the beginning of interstellar space.

Whether Voyager 1 has reached the first boundary or is still on approach remains unclear as, scientists provided evidence for both possibilities on Wednesday.

And love the graphic at the BBC page:

[littlemissattitude]

I just love the idea of those craft out there, heading out for wherever they end up. Each of them is so little, compared to the huge expanse of space. But they are there, our first material representatives to the larger universe (not the first overall - there are all those radio and tv broadcasts that have been streaming out for years and years now. I just love the idea of some alien civilization discovering "I Love Lucy"). It's so cold out there, and so quiet, but those two little parts of us, all of us, carry on into the void, full of purpose and full of the promise of perhaps someday being found by something intelligent enough to know that what they have stumbled on comes from another place, another time, confirmation that we have been here and have thought about them, out there.

[Incognito]

Same here - I just find the whole Voyager concept so mind blowing.

The way they have single-handedly changed our perception of the Solar System - not least its planets and moons - is just staggering. Perhaps they can even teach us something about interstellar space itself. The thought of that - of human-made objects entering the gulf between stars - I find simply staggering. Humanity makes its tentative mark on the galaxy.

[Fijimand]

Now that it has reached out this far maybe it will answer questions that astronomers have had, about comets and why the course change happens, or why pluto's orbit is so strange or why the galaxy goes from rocky planets to gasous to rock material again

[I, Brian]

Absolutely - I hope it begins to answer quite a lot of questions about it all. Why break good habits?