Voyager says Goodbye

[gurnemanz]

As I ponder getting our car repaired (following a mishap involving other half's driving), I hear that the Voyager spacecraft launched 35 years ago and now 11 billion miles from the Earth and hurtling ever further away at a rate of 10 miles per second is about to leave the Solar System. The "Pale Blue Dot" photo it took of our planet helps to put the annoyances of daily life into perspective.

[aka Calum Da Jazbo]

[kernelbogey]

I have participated several times in an experiential exercise called The Earth as a Peppercorn. You lay out in a line objects representing the sun and planets of a size in proportion to the earth represented by a peppercorn - e.g. a walnut for Jupiter. You start with a ball or balloon about eight inches in diameter to represent the sun, then pace out the intervals between the planets in proportion. By the time you've got to Pluto, you're about half a mile from the 'sun', by now scarcely visible.

If the edge of our solar system - where Voyager now is - lies half-way between the sun and the next nearest star, Alpha Centauri, where is that edge on the same scale? The answer is - as far as Moscow is from London.

This is a terrific exercise for anyone to do and a good education for kids. Reading about it (e.g. this post) is nothing like the experience of doing it. The distances and dimensions may be approximate, but most of us have no means of conceptualising the distances involved.

[Roehre]

....
If the edge of our solar system - where Voyager now is - lies half-way between the sun and the next nearest star, Alpha Centauri, where is that edge on the same scale? .....

Alpha Centauri is at 4 light years distance, I'm afraid

[Roehre]

I have participated several times in an experiential exercise called The Earth as a Peppercorn. You lay out in a line objects representing the sun and planets of a size in proportion to the earth represented by a peppercorn - e.g. a walnut for Jupiter. You start with a ball or balloon about eight inches in diameter to represent the sun, then pace out the intervals between the planets in proportion. By the time you've got to Pluto, you're about half a mile from the 'sun', by now scarcely visible.

You can do a solar system walk along the Brienzer and Thun lakes in Switzerland. Walking at normal pace you still travel much faster than the speed of light within that model of the solar system. And it still takes the best part of a day to walk between the sun and Pluto.

[kernelbogey]

Roehre - do look at the link. I'm trying to convey the big picture here....

[johncorrigan]

Roehre - do look at the link. I'm trying to convey the big picture here....

Thanks for all that - especially 'the earth as a peppercorn' - any idea how far Voyager 1 and 11 are from each other?

[Jonathan]

Isn't Proxima centauri the nearest star to us at (IIRC) 4.2 Light years?

[Eine Alpensinfonie]

Thanks for all that - especially 'the earth as a peppercorn' - any idea how far Voyager 1 and 11 are from each other?

Presumably they're continuing to move apart, travelling in quite different directions.

[Eine Alpensinfonie]

One of the fascinating things about the Voyager missions was the confirmation of many of the hypotheses of Arthur C. Clarke in his book 2001 - A Space Odyssey. N.B. I do mean the book, and not the rather crazy film that people rave about, and then say how marvellous it is, because they can't understand it. The book makes it all perfectly clear and is the better for it.

[secret squirrel]

Eric Idle summed it up very nicely in "the Meaning of Life"'s Galaxy song:

Just remember that you're standing on a planet that's evolving
And revolving at nine hundred miles an hour,
That's orbiting at nineteen miles a second, so it's reckoned,
A sun that is the source of all our power.
The sun and you and me and all the stars that we can see
Are moving at a million miles a day
In an outer spiral arm, at forty thousand miles an hour,
Of the galaxy we call the 'Milky Way'.
Our galaxy itself contains a hundred billion stars.
It's a hundred thousand light years side to side.
It bulges in the middle, sixteen thousand light years thick,
But out by us, it's just three thousand light years wide.
We're thirty thousand light years from galactic central point.
We go 'round every two hundred million years,
And our galaxy is only one of millions of billions
In this amazing and expanding universe.

The universe itself keeps on expanding and expanding
In all of the directions it can whizz
As fast as it can go, at the speed of light, you know,
Twelve million miles a minute, and that's the fastest speed there is.
So remember, when you're feeling very small and insecure,
How amazingly unlikely is your birth,
And pray that there's intelligent life somewhere up in space,
'Cause there's bugger all down here on Earth.

I bought myself a 6" telescope in the Spring, and while it has been a delight to use, no-one pointed out the "this will make your brain hurt" side-effect...

For example, looking at the Andromeda Galaxy that is (I am informed) approx 2.5M Light Years away... owch, that hurts!

[Resurrection Man]

I rather like this sequence http://www.youtube.com/watch?v=9e6xkrj8eKI

[johncorrigan]

Presumably they're continuing to move apart, travelling in quite different directions.

Seems as of March 2012, Voyager 1 was at a distance of 17.9 Billion Kilometers (119.9 AU) from the sun and Voyager 2 at a distance of 14.7 Billion kilometers (98.3 AU) heading for the heliopause. I'll need to get the slide rule out.

http://voyager.jpl.nasa.gov/mission/interstellar.html

[Boilk]

Eric Idle summed it up very nicely in "the Meaning of Life"'s Galaxy song:

The universe itself keeps on expanding and expanding

I'm not sure that is the prevailing scientific thought, a few decades on.

The rate at which it is expanding is observably decreasing. Eventually the expansion will grind to a halt and, due to the gravitational attraction between objects (which was always there but overpowered by the Big Bang explosion), there will supposedly eventually be an accelerating contraction of all matter to a single mass.

One then wonders if it's an alternating cycle of big bangs and contractions.

[Flay]

.One then wonders if it's an alternating cycle of big bangs and contractions.

Bang and gnab.