"Scientific" Dreams Of Travel To Stars Shattered: Mysterious Force Pulls Back NASA Probe In Deep Space

Orval Fairbairn wrote:

Could it be fluid dynamic drag, due to traveling through the miniscule
solar atmosphere way out there? There is, after all, some interstellar
gas there.

It's all moving away from the sun faster than the spacecraft is, isn't
it? That would tend to drag it *faster*.

Orval Fairbairn wrote:

Could it be fluid dynamic drag, due to traveling through the miniscule
solar atmosphere way out there? There is, after all, some interstellar
gas there.

What about cold dark matter?

In article ,
Orval Fairbairn wrote:
A space probe launched 30 years ago has come under the influence of a
force that has baffled scientists and could rewrite the laws of
physics...

Could it be fluid dynamic drag, due to traveling through the miniscule
solar atmosphere way out there? There is, after all, some interstellar
gas there.

Not enough -- by multiple orders of magnitude -- to have a detectable
effect, even one this small. Not via known mechanisms of drag, anyway.

There is currently some work underway (note that the quoted news report is
several years old) to try to define exactly what *direction* the
mysterious force is acting in: toward Earth, toward the Sun, along the
antenna axis, or against the direction of motion. (These are similar but
not quite identical directions.) This could reveal the general nature of
what's going on:

+ Toward Earth would almost certainly mean that the "force" is actually
some kind of error in the tracking or data analysis.

+ Toward the Sun would probably mean new (gravitational?) physics.

+ Along the antenna axis would almost certainly mean some kind of
engineering issue, like gas leakage or photon thrust from radiated heat.
Because the spacecraft spins around the antenna axis, most any force
produced by the spacecraft acts, on average, along that axis. Thrust from
radiated heat is a particularly contentious issue because modeling where
all the radiated heat goes is tricky; not everybody is convinced that this
explanation has been thoroughly ruled out.

+ Against the direction of motion would probably mean some kind of drag,
although heaven knows what would be doing it.
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |

: (Henry Spencer)
: There is currently some work underway (note that the quoted news
: report is several years old) to try to define exactly what *direction*
: the mysterious force is acting in: toward Earth, toward the Sun, along
: the antenna axis, or against the direction of motion.

How do you pick a "direction of motion"?
Or equivalently, how do you single out an inertial frame
in which to reckon this direction?

: + Against the direction of motion would probably mean some kind of
: drag, although heaven knows what would be doing it.

Ah. So presumably wrt some material presumed "at rest".
But then... dark matter, or something else exotic, might be flowing
differently than the mundane stuff we can measure, so... still seems
a problem. Most any of the "none of the above" directions could be
"the direction of motion", seems like.

Not that whatever direction is discovered wouldn't be interesting...


Wayne Throop http://sheol.org/throopw

"jonathan" wrote in message
. ..

wrote in message
ups.com...
raven1 wrote:
And your point is...?

Not that the probe has discovered where the dark matter starts... no,
but instead that when C. S. Lewis wrote about "God's quarantine
regulations", he didn't know the half of it!

God knows how clever humans are at getting around limits. After all, He
destroyed the Tower of Babel.

"Heaven, even the heavens, are Gods; the Earth He has given to the
children of men" - and so the probe is just now bumping into the
firmament!

Those Weekly World News stories about the Hubble Space Telescope taking
pictures of angels in Heaven, while perhaps not true, are, apparently,
not utterly implausible.



Interstellar travel is a waste of time, the only thing 'out there'
is the past.

You are kidding, aren't you?

GLB







John Savard

"raven1" wrote in message
...
On 5 Oct 2006 15:37:43 -0700, "Sound of Trumpet"
soundoftrumpet@


A space probe launched 30 years ago has come under the influence of a
force that has baffled scientists and could rewrite the laws of
physics.

And your point is...?

His point is this: "If science doesn't know everything, then science doesn't
really know anything. If scientists can still be surprised, then we don't
need to believe anything they say. Our book of fairy-tales could still be
true. God could still be there".

M.

G. L. Bradford wrote:
"jonathan" wrote in message
. ..

Interstellar travel is a waste of time, the only thing 'out there'
is the past.

You are kidding, aren't you?

No, I think that he's misinterpreting General Relativity.

- Jordan

Joe Strout wrote:
This is really exciting research. If the effect is real, it could
indicate the need for revision our theories of gravity -- and that, in
turn, is likely to have repercussions on other theories (dark matter
comes immediately to mind).

However, what's really astonishing is the level of ignorance required to
read this article, and then type a subject line like "Dreams Of Travel
To Stars Shattered". How can you read about an acceleration of 6 mph
per century, and not see that this would be absolutely no impediment to
interstellar travel?

It's _that_ weak a force? Then it could be dark matter, or it might
just be a thicker-than-expected concentration of interstellar dust or
gas producing _friction_.

I _do_ find it amusing that SOT didn't even bother to notice what the
force actually had accomplished.

The analogy would be mariners discovering the Gulf Stream and deciding
that "Dreams of Travelling to the New World" were "Shattered." Except
that, of course, the Gulf Stream is a relatively far greater force
compared to 15th-century sailing vessels than this force is compared to
even a drifting space probe.

- Jordan

In article .com,
"Sound of Trumpet" wrote:

Research to be published shortly in The Physical Review, a leading
physics journal, will show that the speed of the two probes is being
changed by about 6 mph per century - a barely-perceptible effect about
10 billion times weaker than gravity.

Yeah, that'll be SURE to keep us bottled up in the region for eternity.

--
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Atheist #1331 (the Palindrome of doom!)
BAAWA Knight! - One of those warm Southern Knights, y'all!
Charter member, SMASH!!
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Quotemeister since March 2002

In article ,
raven1 wrote:

A space probe launched 30 years ago has come under the influence of a
force that has baffled scientists and could rewrite the laws of
physics.

And your point is...?

Where else? At the top of his skull.

--
Nemo - EAC Commissioner for Bible Belt Underwater Operations.
Atheist #1331 (the Palindrome of doom!)
BAAWA Knight! - One of those warm Southern Knights, y'all!
Charter member, SMASH!!
http://home.earthlink.net/~jehdjh/Relpg.html
Draco Dormiens Nunquam Titillandus
Quotemeister since March 2002