throopw@dg_rtp.UUCP (Wayne Throop) (10/23/86)
NOTE: followup-to set to sci.astro A recent issue of Science News had a bit on the apparent "FTL" gas/plasma jets that occur now and then. They invoked special relativity as the favored explanation, saying something like "The jets are moving FTL in *our* frame, but they are moving STL in their *own* frame." This seems to be nearly pure male bovine excrement. SR says that *nothing* can move FTL as measured from *any* frame. Further, the speed of anything at all "in its own frame" is zero, so that isn't an explanation of anything. The last time I heard this discussed, it was purely an optical illusion having nothing to do with SR, but rather to do with the angle at which we are observing the gas jet, so that we are (in essence) seeing its lifetime in "fast motion". Can anybody say if the reporter mangled the story into unrecognizability, or just what is going on here? Just what *is* the current idea about these "FTL" jets? -- You run and you run to catch up with the sun, but it's sinking, racing around to come up behind you again. The sun is the same in a relative way, but you're older, shorter of breath and one day closer to death. --- Pink Floyd -- Wayne Throop <the-known-world>!mcnc!rti-sel!dg_rtp!throopw