Paul, You claim that "[Robert's] references to the direction of the Zenith and the Sun and the time of day for the launch are entirely spurious." Whilst I leave Robert to answer your posting, I just want to state that I did not myself understand the significance of the Zenith at dawn and noon until I went back and re-read the post. Robert is discussing here both the alleged rotation of the World and the alleged orbit of the World around the Sun. If you reconsider this fact I hope that you will see that there is nothing "entirely spurious" about the vector addition of the launch velocities and their would-be dependence upon time of day. Neville. Paul Deema <paul_deema@xxxxxxxxxxx> wrote: Robert B Catching up with PM From Robert Bennett Thu May 3 20:18:45 2007 Robert, a recent communication from you indicates that you are much more highly educated than I am; I discern that you may very well have a significantly greater intelligence than I possess; by your performance on this forum, you are undoubtedly more well read than I am. Why then do you make the kind of statements (out of deference to you, here included in blue) which at first glance seem almost designed to convey to the reader the impression that you are ignorant, slow, and unschooled? At dawn the site?s zenith would be directed in the orbital direction, boosting the launch speed 100 times more than the rotation speed! However, a noon launch would be pointed at the Sun, with no orbital boost. Most launches are shortly after dawn. Yet when the Pioneer third stage has fired, the speed is said to be only 10 to 15 km/s, which includes the rocket boost?.. What happened to the 30 km/s boost, MSers? In Fig 1 attached, the various velocities are shown from the heliocentric position. Though you've given heliocentric data, I'm aware that you are not a proponent of the heliocentric position -- not to put too fine a point on it, you never miss an opportunity to denigrate with sarcasm and ridicule (eg Cape Carnival) the whole model and the science which supports it. Though I regard this as poor form, none the less, I suppose it is your prerogative. But this, in my humble opinion, does not give you license to dismiss the model with what, having cognizance of your previously attested to qualities, I can only regard as deliberate misrepresentation. Challenge the model if you will, but do it honestly. You report the statement that the velocity of the vehicle is only 10 to 15 km/s as though this is an absolute value. You must know that this is relative to Earth. Indeed, the velocities you quote bracket that important parameter -- Earth escape velocity. As shown in the illustration, if this velocity is in the same direction as the Sun orbital velocity, then they add, and there is your 'missing' 30 km/s. Even if they subtract, still, there it is. True for all angles in all three planes. Your references to the direction of the Zenith and the Sun and the time of day for the launch are entirely spurious. I'm sure there are good and proper reasons why launches take place at the times they do, though they probably have more to do with lumping the major load on the day shift and thus avoiding excessive penalty rates to the 'after hours' support staff than anything to do with physics. But again, I believe you must be aware of the basics of Hohmann Transfer Orbits. With this knowledge, you must be aware that a launch can take place at almost any convenient time, leaving the vehicle in a parking orbit until convenient to give it that final push which will put it on a trajectory which intersects the orbit of the target body when the target body is nearby. Why then do you seek to confuse the issue? "Since the Pioneers are just remote satellites, their motion and the Earth?s also must be modeled in HC." Again having cognizance of your acknowledged qualities, you must know that, from the HC position at least (and I'd guess GS also) the Pioneers are definitely not remote satellites of Earth. One at least is no longer even a satellite of the Sun, but I'm not sure of the other. "...this must be used, since the Earth and Pioneer and all else orbit the Sun ? though relativity says it doesn?t matter. Right away, then, there?s a logical contradiction ? which MSP ignores, per usual." If you'll permit me a personal opinion here -- this, among others, is what I have come to regard as the 'Bennett Spin'. While I don't pretend to be able to usefully debate relativity, to be able to relate this given quantity relative to that location, does not change the reality that this body orbits that body. There is no contradiction to be ignored. "At Jupiter?s distance the angle between Sun and Earth is less than one degree ? usually much less." If I'm barking up the wrong tree here, please correct me, but at the moment, the way I figure it, it looks like this - Sun/Earth 93 * 10 ^ 6 mi Sun/Jupiter 483.9 * 10 ^ 6 mi asin(93 * 10 ^ 6 / 483.9 * 10 ^ 6) = 10.9 deg Still -- the error is only a little more than one order of magnitude. All up, you should be able to see why I would never quote you in an argument. Paul D --------------------------------- What kind of emailer are you? Find out today - get a free analysis of your email personality. Take the quiz at the Yahoo! 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