Quote:
|
Originally Posted by John T
The explanation appears to be that spacecraft such as Soho, Ulysses etc soon become very highly negatively charged with respect to the surrounding space plasma and in addition to being embedded within the "solar wind", the combined effect causes these slow-drifting electrons to remain virtually undetectable.
Charged in this way, the velocity of these spacecraft through the plasma/solar wind would also have little effect in the detection of any accumulated electrons, as the spacecraft are also highly charged.
If it were possible, it seems that only a specially designed spacecraft sent sufficiently close to the sun (perhaps near the corona), could actually detect these incoming electrons.
|
I don't buy it. If Cassini were highly negatively charged, our instrument (INMS - Ion and Neutral Mass Spectrometer) wouldn't work properly, nor would most of the other plasma and fields instruments. We'd all notice when the voltages on our electronics went out of spec. There
is some negative charging due to the solar plasma, but (from what I understand) it is on the order of a few volts. Not enough to push electrons away if they are approaching the sun with any appreciable velocity, which they would have to be (see below).
Also, we are heading straight into this supposed electron flow, but CAPS's ELS (ELectron Spectrometer) doesn't see them. When it looks away from the sun, there is essentially nothing to see. The low energy "glow" is that slight negative charging that the spacecraft has and can be seen no matter where CAPS is looking.
http://nis-www.lanl.gov/nis-projects..._anl_tool.html
And don't expect anything else back from Pioneer: the last signals from 10 and 11 were recieved one and 7 years ago respectively.
http://spaceprojects.arc.nasa.gov/Sp...er/PNStat.html
And anyway, how would you explain the massive number of electrons leaving the sun? How do these slow moving inbound electrons (to complete the "circuit") get past that, if they can't get past the few volts on a spacecraft? They'd have to be moving quickly, but we don't see them, so that explanation doesn't work.