root@decwrl.UUCP (01/11/84)
From: dvinci::fisher (Burns Fisher, MRO3-1/E13, 231-4108) > ...in 1988 the Voyager 1 satellite will become the first to cross the > orbits of all nine planets...Pioneer 10 (somehow missed) Pluto. 1) Voyager is not a satellite...it is going fast enough so that it is not in orbit. That is why it is leaving the solar system! 2) How can a probe which was launched from the third planet to the fifth cross the orbits of the first and second? It could have made a funny energy-change maneuver by grazing the sun or one of the inner planets, but it did not. Therefore, I contend that V 1 will only cross the orbits of 6 planets, having started at the orbit of a seventh (Earth). 3) For the next point, let's define "cross the orbit of" to mean "exceed in distance from the sun the mean radius of the orbit of". If you actually insist that cross means "occupy the same volume of space that <planet> will at some point in its orbit" I suspect the crossings would be very few. In any case, then, I don't see how P10 can avoid crossing the orbit of Pluto at some point! I think the writer got a bit confused about the fact that Pluto was closer to the sun than Uranus when P10 crossed U's orbit. P10 still will cross, or already has crossed (depending on which side of the solar system it is on) Pluto's orbit. End of obnoxious nitpicking. Does anyone know if NASA plans to leave any of P10's (and the other 3 probes as well) equipment on as it leaves communication range? Maybe a beacon to help some interstellar voyager find them later? If so, how long will the nuclear generators last to keep the beacon running? Burns UUCP: ... decvax!decwrl!rhea!dvinci!fisher or ...allegra!decwrl!rhea!dvinci!fisher or ... ucbvax!decwrl!rhea!dvinci!fisher ARPA: decwrl!rhea!dvinci!fisher@Berkeley or decwrl!rhea!dvinci!fisher@SU-Shasta