--------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F4B00003 Date: 04/06/98 From: MIKE ROSS Time: 01:23am \/To: A.G.G. (Read 1 times) Subj: Are atoms expanding? Well, I've just come across some interesting news relating to what AGG said was my "ad hoc" explanation on whether atoms are expanding: > New scientist 28 March 1998 reports that a group of scientists have > reported possible time-dependence of the fine structure constant > after studying the spectra of quasars. The fine structure constant is a dimensionless ratio relating the electron's orbital velocity to the speed of light. If this value was significantly different, a lot of our biochemistry would be different. This value is roughly about 1/137. This ratio however varies with changes in momentum and of course with changes in the speed of light. Of interest with the latter is that the speed of light can change in the presence of strong electromagnetic or gravitational fields as stated by QED. This effect was in fact observed in the 1930's. The effect is negligible on the Earth or even near the Sun but it is appreciable near neutron stars and BH's which have enormously intense fields. Now the above report states that this constant is tied to the arrow of time. Since we know that time flows at different rates this means that the fine structure constant was different in the past or in other words in very distant objects and atoms may in fact be a different size there. --- Blue Wave/DOS v2.30 * Origin: Juxtaposition BBS. Lasalle, Quebec, Canada (1:167/133) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F4B00004 Date: 04/03/98 From: JIM VAN NULAND Time: 04:36pm \/To: TIM EDWARDS (Read 1 times) Subj: Star Constellations >I found a fine ShareWare program some years back, and saw to it that it >was posted to the local Astro-club BBS, as well as bringing disks (copy >charge priced) to public events... Deep Space 3D. It's now sold as a CD. This one has a happy ending: the person publishing the CD is the original author -- he did NOT sell it to anyone. And the shareware version is still available on a number of shareware sites. * SLMR 2.1a * Open mouth, insert foot, echo internationally.... --- Maximus/2 3.01 * Origin: [PC-TIE BBS] (1:143/11) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F4B00005 Date: 04/05/98 From: BARTON PAUL LEVENSON Time: 06:15am \/To: LANCE REYNOLDS (Read 1 times) Subj: ASTEROID PASSING CLOS BPL> No, this is just quantitatively wrong. The impulse would be BPL> enough to radically change the orbit, the earlier the wider. BPL> Do the math. LR> Ok, I'll bite. What is quantitativly wrong? My point was about being LR> able to make the roid into pieces small enough to not hurt when they LR> hit. I didn't think of just knocking it off its path. LR> And as a point of order, some of us (still mostly useful human beings) LR> weren't lucky or talented enough to acquire the math that you so LR> blithely rubbed in my face. If you don't understand the math, you don't understand the problem, and therefore have no right to an opinion on the subject. LR> Perhaps, if you could come down off your pedestal long enough, you LR> could explain the math, or some rudimentary portion thereof, to one LR> less fortunate than your lofty (somewhat snooty) self. Sure. Kinetic energy E(k) = 1/2 m v^2 in a Newtonian framework, where m is mass in kilograms, v velocity in meters per second and energy comes out in Joules. Nuclear explosive power is gauged relative to the explosive power of the chemical explosive, 2,4,6-trinitrotoluene (TNT). A gram of TNT yields 4,200 Joules of explosive energy. Say you want to increase, or decrease, the velocity of an asteroid by a given amount, enough to miss the Earth. Let's say the asteroid is traveling at 30,000 meters per second, a representative speed for Earth-crossers. If detected on a collision course from say, 10,000,000,000 meters away, and given that Earth's diameter is 6,378,040 meters (I'm using the equatorial figure), a velocity difference of about 0.06% would be of the right order of magnitude to avoid hitting the Earth. More precise calculations would involve the asteroid's actual path and the angle at which its orbit will cross ours, but we can leave that aside for the moment. Say the asteroid is 1,000 meters in diameter and roughly spherical, with a density equivalent to that of surface rocks on the Earth (about 2,800 kilograms per cubic meter). The volume of a sphere is (4/3) pi r^3, or here about 5.236 x 10^8 m^3, giving it a mass of around 1.4661 trillion kilograms. With the velocity cited earlier, the kinetic energy is 6.5974 x 10^20 Joules. A difference of 3.9584 x 10^17 Joules must be made in its kinetic energy. By the conversion factor cited, this is about 94 megatons of explosive energy. Assuming no conversion of the bombs into shaped charges, the efficiency of transfer would probably be low, perhaps 10%. Therefore 940 1-megaton bombs would be needed. Since we and the Russians between us have about 50,000 warheads available, many in that yield range, deflecting the asteroid is well within our capabilities. --- Maximus 3.01 * Origin: SoundingBoard, Pittsburgh PA (1:129/26) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F4B00006 Date: 04/05/98 From: BARTON PAUL LEVENSON Time: 06:26am \/To: BOB KING (Read 1 times) Subj: S of L. BK> Hi, > Huh? Mass is a property of some elementary particles. > There's no arguing > that mass doesn't exist. BK> So how do the experts reason that you can have a massless particle? BK> sig rex Some particles, not all particles. Quarks have mass, leptons have mass, but photons and gravitons, and perhaps the neutrino, don't. --- Maximus 3.01 * Origin: SoundingBoard, Pittsburgh PA (1:129/26) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F4B00007 Date: 04/05/98 From: BARTON PAUL LEVENSON Time: 06:29am \/To: EARL TRUSS (Read 1 times) Subj: our moon ET> Below is what Encarta has to say about Pluto. From this, it does not ET> sound like Pluto's "moon" is oddly-shaped since they refer to its ET> "diameter". Were you thinking of the moons of Mars? They are efinitely ET> odd-shaped and less than 100 km at their widest points. The diameter is twice the radius of a sphere. Charon is 635 km. in radius and 1270 km. in diameter, and very close to a sphere. --- Maximus 3.01 * Origin: SoundingBoard, Pittsburgh PA (1:129/26) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F4B00008 Date: 04/05/98 From: BARTON PAUL LEVENSON Time: 06:33am \/To: MARTYN HARRISON (Read 1 times) Subj: BB & apology First, the apology -- I'm sorry for jumping all over you the way I've been doing. I've just come off a year of debating Big Bang v. Steady State on the AOL astronomy boards, and I'm still in nuke-the-opposition/take-no-prisoners mode. I'll try to calm down. MH> rate was increasing, we could reverse the expansion process back to the MH> point where the expansion rate was zero. This *is* *not* what would be MH> the case in a big bang origin, although this seems to have avoided MH> scrutiny. The big bang was, of course, the explanation for why the MH> universe is expanding. Now if we know it can expand on it's own, we MH> don't need it (but it's become entrenched). MH> Ho hum, it'll probably be retracted soon. I think you're assuming above that the expansion rate has to be zero at the moment of the Big Bang. I don't think that's needed. If you extrapolate back the current expansion rate, depending on what model you're using, everything fits together 10-20 billion years ago, which is evidence for the Big Bang. --- Maximus 3.01 * Origin: SoundingBoard, Pittsburgh PA (1:129/26) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F4B00009 Date: 04/05/98 From: BARTON PAUL LEVENSON Time: 06:36am \/To: MARTYN HARRISON (Read 1 times) Subj: A 5th force? MH> Einstein was wrong, and his presumption that the universe was steady MH> state is still wrong. His fudge factor is wrong. MH> Whoever invented this notion that the fudge factor is equivalent to the MH> fifth force is also wrong, they're two entirely different fudge factors, MH> one is designed to "correct" maths which point towards an expanding MH> universe, the other is in response to the finding that the expansion MH> rate is being added to, not merely draining away due to gravity. But they're not. A positive cosmological constant = a force expanding the Universe. If lambda is positive, there's a fifth force. (If it's negative there's also a fifth force, but attractive instead of repulsive). --- Maximus 3.01 * Origin: SoundingBoard, Pittsburgh PA (1:129/26) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F4B00010 Date: 04/05/98 From: JOHN PAZMINO Time: 09:02pm \/To: TIM EDWARDS (Read 1 times) Subj: Star Constellations TE> JK> TE> Read the documentation. Shareware is a distribution method for TE> JK> TE> comercial software. Use of shareware beyond the trial period TE> TE> JK>Actually, he is right. Shareware is *not* commercial software, it is privat TE> TE> ??? Compare the last distribution of Procomm before they converted from TE> ShareWare to ShrinkWrap, and you will see that successful ShareWare is of TE> far higher quality than most products sold on Hype, such as Windows. This is the exception. Virtually all shareware ends up ultimately as, well, shareware. Oh!, what about sellware that turns into freeware? Look at STK. Price went from, um, $8,000 -- NO!, I don't make up this stuff! -- to zero. SO I called the publisher and, yes, it shot off the CD to me. Just like that. If I called but two weeks earlier, I'd be living today in a refirgerator crate. And!, this past Christmas I get a lovely, like LOVELY, desk calendar from the STK people with gorgeous printouts from STK as the pictures for the monthly sheets. All for being a valued 'customer'. TE> JK>And for the record, any shareware which we have used and found acceptable--a TE> JK>use regularly--has had the shareware fees paid at The Northland Connection. TE> JK>Now, can we get back to talking about astronomy again, please? TE> TE> I found a fine ShareWare program some years back, and saw to it that it TE> was posted to the local Astro-club BBS, as well as bringing disks (copy TE> charge priced) to public events... Deep Space 3D. It's now sold as a CD. It's still freely distribuible. Look in almost any astro software library. In fact, the CD of Deep Space 3D (which I did eventually purchase) has the free passalong edition on it. --- RoseReader 2.52 P005004 * Origin: MoonDog BBS Brooklyn,NY 718 692-2498 (1:278/15) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F4B00011 Date: 04/05/98 From: JOHN PAZMINO Time: 09:08pm \/To: MARK KAYE (Read 1 times) Subj: Tasco Buys Celestron MK> Tasco is going to buy Celstron International. This is good news for all MK> amateur astronomers as now all C8s through C14s will come shipped with three MK> quality Huygens oculars and a 3X barlow! Old news. Tasco makes the Celestron 'First Scope'. Actually the theory is that Tasco is a front for a cabal made of Celestron and Meade. They let Tasco sell the trasco scopes, get the revenue from the sales. And sit back and watch the hordes come crawling to them directly for real and proper telescopes. And they collect revenue from these new sales, too. --- RoseReader 2.52 P005004 * Origin: MoonDog BBS Brooklyn,NY 718 692-2498 (1:278/15) --------------- FIDO MESSAGE AREA==> TOPIC: 180 ASTRONOMY Ref: F4B00012 Date: 04/05/98 From: JOHN PAZMINO Time: 09:12pm \/To: JIM VAN NULAND (Read 1 times) Subj: Where? JV> > > easy info about astronomy on internet? And, what books will be good JV> > > to start with? I'm not intersted in getting something like a JV> > > telescope if I don't know in what use it. JV> JV> You need to get in touch with your local astronomy club. They may be JV> running a beginner's class! Hit your library and look for the back-file JV> of Sky & Telescope magazine, or of Astronomy. They used to have have JV> lists of clubs: the May issue of Astronomy, and the September issue of JV> S&T. Call the nearest if none of them are handy by, as there are other JV> clubs not listed, but are usually known by their neighbors. A bit out of date. The two zines dropped their club rosters two years ago! But you do note the ebsites, which do continue the roster. --- RoseReader 2.52 P005004 * Origin: MoonDog BBS Brooklyn,NY 718 692-2498 (1:278/15)