What is the fastest we’ve ever gotten something with mass to go?
I think particle accelarators have gotten electrons (and other particles) up very close to the speed of light. The exact speed I don’t know, though.
A particle accelerator can get an electron up to very near the speed of light. Like, 99 percent or so. Anyone wanna do the math for how fast a 50 Gev electron is going?
If you are talking about a macroscopic object, Voyager 1 is hauling some serious booty at about 38,000 MPH with respect to the sun, or 84,000 MPH with respect to the earth.
Well, an electron has a rest energy of, IIRC, about .5 keV (too lazy to go for my books right now), so that’s a gamma of 10[sup]8[/sup]. gamma = 1/sqrt(1-v[sup]2[/sup]), so v = sqrt(1 - 1/gamma[sup]2[/sup]), or approximately, for large gamma, v = 1 - 2/gamma . This means that a 50 GeV electron would have to be going at 1 - 2*10[sup]-8[/sup] times the speed of light, or .99999998c . Fast enough for ya?
Er, that should be 0.511 MeV not keV. Otherwise you’d get pair production from soft X-rays. So it’s a gamma of 10[sup]5[/sup], or a speed is .99998c.
This seems as good a place as any to mention the fasted-moving particle with mass ever detected, as opposed to accelerated, by mankind: the so-called Oh-my-God Particle, an ordinary cosmic-ray proton travelling at 0.9999999999999999999999951 times c.
More information and some fascinating facts can be found at http://www.fourmilab.ch/documents/ohmygodpart.html. It makes you realise how slow our .5 MeV electrons in the big scheme of things.
Jason meant to post THIS link: The Oh-My-God Particle
Fastest a Human has ever travelled
24,791 mph (relative to the earth) by the crew of Apollo 10 in May, 1969.
Fastest Thing We’ve Ever Witnessed
(See link to Oh My God Particle in an earlier post above)
**Fastest Humans have Accelerated Anything **
(See posts on Particle Accelerators above)
Fastest Spacecraft
Not sure. I thought it was the Ulysses Space Probe but the only speed I could find for it was 34,000 mph which makes it slower than Voyager’s roughly 40,000 mph speed. I’m tired of looking so any help here would be appreciated.
Fastest Spacecraft on the Drawing Board
Due for launch in 2010 is an instellar probe that will travel 208,800 mph (58 miles per second or New York to LA in less than a minute). This is 5 times faster than Voyager and it will actually catch and pass Voyager in 2018 (going as far in 8 years as Voyager went in 41 years).
*Source: http://www.msfc.nasa.gov/NEWSROOM/news/releases/2000/00-150.html *
Jeff_42:
Hmph. Call me a grumpy prescriptivist grammarian, but the referenced article doesn’t suggest the sailcraft will be going to another star. Looks like it’s only going out 250 A.U.'s, which is significantly less than the distance to any other star.
I’d call it an extrasolar spacecraft.
[nitpick]
Well, if you want to nitpick I’d say that Nasa’s own document describes it as am “instellar” probe.
I’d also mention that to me the word “interstellar” translates as “between stars” which is exactly where that probe will be (that definition could also include me as well so I’ll expand it by saying that it has to be outside of our solar system to make the term meaningful).
Finally, although the probe may become worthless it will continue travelling well beyond 250 A.U. short of its destruction. So, barring a collision or a drop into a black hole (both very unlikely) that probe may well one day reach another star thus making it interstellar by your definition.
[/nitpick]
Make that…
Well, if you want to nitpick I’d say that Nasa’s own document describes it as an “interstellar” probe.
So who’s going to lay the smack down with the whole frame of reference thing?
Assuming that V1 is travelling along a vector pretty much in line with the solar plane, wouldn’t that last number (w/r/t/Earth) vary depending on what time of year it was? And in some cases be less than the first number? If so, are you quoting the maximum number?
Also, assuming the plane thing is not true, wouldn’t the two numbers be approximately the same?
So what’s the deal with this Oh-my-God Particle? How do they know it’s a proton, and not some other (possibly unknown) particle? I’ve looked over the Univeristy of Utah site, but couldn’t get an answer to how they determine the incoming particle. Unfortunately, the “Detected a Proton” link on Friedo’s correction to JasonFin’s link doesn’t work.
ok, we all know that light has mass, so the photon would be the fastest. Big F$%^en deal, traveling naturally at .0000000000001c faster then what we can push. but here’s the kicker, photons can and have proven to travel faster then c, reaching a speed about 1.7c . The process is microscopic tunneling and don’t know much about it.
Basically a photon is directed twards a high density material. most of the photons are absorbed/reflected but some travel to the far end at about 1.7c. I think it has to do with microscopic wormholes but that is just a guess
Where to begin, k2dave… First off, depending on your definition of “mass”, photons are massless. Seeing as the OP specified “with mass”, I think it’s safe to assume that he meant “rest mass”, in which case photons are out. Secondly, photons can not travel faster than c, as we’ve discussed at nauseating length already. I would provide links, or tell you to search, but there’s several threads about it in the first couple of pages of GQ. Read them. The summary is, that those experiments just showed what appeared in some respects to be a photon travelling at faster than c, not an actual fast photon.
IIRC, the Guinness Book of World’s Records states that the fastest that any solid visible object has been propelled (other than spacecraft) are plastic disks accelerated to 18,000 mph by explosive charges in a vacuum.
Sorry for not linking. I was going from the latest weekly report of Voyager available from JPL. Thus I wasn’t taking an average value, but rather a ‘June 30, 2000’ datapoint. They have posted the data for July 7 now.
As for your questions, yes I’m sure it varies quite a bit throughout the year. As for the plane of orbit, IIRC Voyager 1 turned ‘up’ when it hit Saturn, and Voyager 2 may similarly have diverged from the ecliptic. However, it would have to be at close to 90 degrees and very far away for Earth’s orbit to not have an effect. If it only turned out about 30 degrees or so, earth’s orbit will always have an effect on the relative velocity.
By the way, they list orbit information for Voyager at the site, but it is all in inclination and ephemeris and other orbital mechanics terms I’m not familiar with. Guess I should have gotten that double major in Astrophysics afterall.
we all know photons have mass and travel at c.
also I recall something like subatomic tunneling that would allow a few photons to travel through a dense material at about 1.7c. I think it has to do with tiny wormholes but not sure - just remember thaT the photons travel 1.7xthat of regular light through the atmosphere (I know that light through the atm goes a little slower then c, but close enough to say that this subatomic tunneling goes a heck of alot faster).
No, we don’t all know that photons have mass. Many of us know that photons do have a mass equivalent to their energy (sometimes called “relativistic mass”), and if you define “mass” that way, then photons have mass. However, by this definition, everything has mass, and it doesn’t make sense for the OP to ask specifically about things with mass. The more common definition of “mass” among physicists is rest mass, and a photon has zero rest mass. By this definition, the OP makes sense. As for the fast photons, I’ll say it again: We have never gotten photons to go faster than c, and it is extremely unlikely that we ever will. What we have done, however, is cause photons in some situations to appear to move faster than c. This is an illusion, not an actual effect. And quantum mechanical tunneling, btw, has absolutely nothing to do with wormholes. As of yet, there is no direct evidence for wormholes, and even if they exist (probable), it may very well be impossible to manage to get anything, even a single photon, through one. I would tell you to quit while you’re ahead, but you’re not.