Probably because they used a Hp-15 back in the day...
Or Romulan scans. ;)
This might be over my head but I'm glad you posted. I'll bookmark for later. :)
Spacehead bump!!!!!!
I believe that this effect was confirmed during one of Cassini's earth flybys.
Some of these theories suggest that gravity might attract a little harder than expected at large distances or small accelerations, so the concept of dark matter may not even be necessary.
Is it possible/likely that the acceleration towards the sun could have been the result of a prolonged encounter with an asteroid, whose orbit took it close enough to Pioneer to affect its path.
Attempts to test the anomaly using other spacecraft such as Galileo and the Voyager probes have proved unsuccessful,
First off, let's be clear what these guys are talking about: the trajectory determination process has shown what appears to be an unexplained perturbation. Apparently the same perturbation has not been noted with Voyager.
Note that the data in question here are tracking data gathered using Very Long Baseline Interferometry.
While it's entirely possible that they're observing some real effect, the apparent lack of corroborating data for other deep space probes suggests to me that there's a subtle error somewhere in the ground system -- probably in the databases used for Pioneer trajectory processing.
It is not clear why the authors have tossed Galileo into this -- it was a Jupiter orbiter, far closer to the sun than the Pioneers and Voyagers, and its perturbation environment was much different. The effect, if real, is being detected outside the solar system.
My bet: it's something stupid and overlooked on the ground. It almost always is.
The tragectories have been effected by cloaked Romulin vessels observing us from the edge of the solar system.
For one thing, there almost can't be anything wrong with gravity. Any gravitational effect large enough to explain the anomaly would noticeably affect the ephemerises of the outer planets. Yes, it is mathematically possible to dream up some function whereby the probes are affected but Pluto and Neptune are not, but that's awfully contrived and poorly motivated.
My expectation is that the probes have acquired a significant electrical charge during their journey. This causes their trajectories to bend slightly as the probes pass through the sun's magnetic field (to say nothing of the local galactic magnetic field). This bending causes the probe to acquire a momentum component that is transverse to its direction of travel, but because its total momentum is roughly constant, its momentum along our line of sight (which is what the Doppler shift measures) is necessarily reduced. We have no way to measure the transverse momentum component.
If this idea has been rejected, I'd like to see a quantitative reason.
Does anyone know if the Mariner craft have exhibted any unpredicted orbital deviations? I think the Mariner craft are still in orbit around the Sun between Earth and Venus if I remember it correctly. Looks like I get to dig around NASA's sites a bit this evening. :-)
-ccm
Those with poor reading comprehension should note that they've just replied to a two year old thread. So don't write in, okay? ;')
But to FairOpinion, here's not one but two 2004 topics, related to each other, and you can write me any time (':
Gravitational anomalies: An invisible hand?
From The Economist print edition | Aug 19th 2004
Posted on 08/21/2004 4:31:57 AM EDT by ScuzzyTerminator
http://www.freerepublic.com/focus/f-news/1196132/posts
from 2004.
Comet's course hints at mystery planet [ from 2001 ]
Govert Schilling | last updated February 5th, 2002 | Govert Schilling
Posted on 08/18/2006 5:36:59 PM EDT by SunkenCiv
http://www.freerepublic.com/focus/f-chat/1686125/posts
