Voyager Close to the Edge

Voyager Pushes for Deep Space

The Voyager 1 probe is getting very close to the edge of the Solar System. Launched in 1977, the craft is now some 14 billion km (8.7 billion miles) from the Sun and on the cusp of deep space.

American space agency (Nasa) scientists told a conference in New Orleans on Tuesday that Voyager was moving through a region known as the heliosheath.

This is a vast, turbulent expanse where the Sun's influence ends and particles blown off its surface crash into the thin gas that drifts between the stars.

Soon - researchers cannot be sure when - the probe will break into deep space.
"Voyager 1 has entered the final lap on its race to the edge of interstellar space," said Dr Edward Stone, Voyager project scientist at the California Institute of Technology in Pasadena, US.

Last November, scientists debated whether Voyager had reached the so-called termination shock region. This is where the "wind" of electrically charged particles coming off the Sun is slowed by pressure from the sparse gas found between the stars.

At the termination shock, the solar wind slows abruptly from a speed that ranges from 1.1-2.4 million km/h (700,000 to 1.5 million mph) and becomes denser and hotter. Some researchers thought the probe had arrived at the shock; others thought it still had some way to go.

Now, at the 2005 Joint Assembly meeting organised by the American Geophysical Union, space scientists say they are confident - and agreed - that Voyager has gone beyond the termination shock and is flirting with deep space. Predicting the location of the termination shock was hard, the researchers say, because the precise conditions in interstellar space are unknown.

Also, changes in the speed and pressure of the solar wind cause the termination shock to expand, contract and ripple.

The most persuasive evidence that Voyager 1 has crossed the termination shock is its measurement of a sudden increase in the strength of the magnetic field carried by the solar wind, combined with an inferred decrease in its speed. This happens whenever the solar wind slows down.

Voyager 1 was initially given a mission life of five years but has continued to perform spectacularly.

The craft is carrying a time capsule in the form of a golden gramophone record, complete with stylus, which contains a recording of greetings from Earth in different languages as well as samples of music ranging from Mozart to singer Blind Willie Johnson.

Its twin, Voyager 2, launched a couple of weeks before Voyager 1, is moving on a different trajectory and is some 10.4 billion km (6.5 billion miles) away.

Check out this cool graphic from BBC:



I'm excited and all about this, but the truth is that we are not going to make any extraterrestrial contact until we can produce a warp signature. I'm not sure what part of that is unclear to NASA. This has been a fabulous experimental, but a grand failure. We need to focus our resources on warp technology so that we can get the attention of more advanced aliens who occaisionally pass by.