Date: Thu, 3 Dec 92 05:00:28 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #488 To: Space Digest Readers Precedence: bulk Space Digest Thu, 3 Dec 92 Volume 15 : Issue 488 Today's Topics: Detonavion vs Deflagration (was Re: Shuttle replacement) Foreign Soil NASA has 5 hand grenades still on the moon from Apollo missions Shuttle replacement (5 msgs) Space probe to pass Earth spherical space structure STS-48 and "SDI": Oberg vs. Hoagland Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu", and (un)subscription requests of the form "Subscribe Space " to one of these addresses: listserv@uga (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle (THENET), or space-REQUEST@isu.isunet.edu (Internet). ---------------------------------------------------------------------- Date: Tue, 1 Dec 92 12:39:25 +0100 From: "John D. Boggs" Subject: Detonavion vs Deflagration (was Re: Shuttle replacement) Newsgroups: sci.space From article <1992Nov30.232333.1@stsci.edu>, by gawne@stsci.edu (): > At least in the language of supernovae research, a detonation involves > a flame front that propogates supersonically, whereas a deflagration has > a subsonically propogating flame front. In the case of supernovae you > get a VERY big ball of fire in the sky. Hmm. And just how fast *does* sound move in space? -John D. Boggs uunet!erato!jdb ------------------------------ Date: 2 Dec 92 13:43:45 GMT From: FRANK NEY Subject: Foreign Soil Newsgroups: talk.politics.guns,sci.space This is also one of the reasons why private space exploration/exploitation will never get off the ground, at least those attempts made by US citizens. The Commercial Space Launch Act requires $3 billion in Liability Insurance for a launch. I called the NY office of Lloyd's once to inquire on the rates for such a policy and was informed that they would not write one. Launching outside the US would not work, since the Foreign Practices Act enforces the Commercial Space Launch Act wherever a US citizen goes....even into outer space. Your only alternative is to renounce US citizenship. Frank Ney N4ZHG EMT-A NRA ILA GOA CCRTKBA "M-O-U-S-E" Commandant and Acting President, Northern Virginia Free Militia Send e-mail for an application and more information ---------------------------------------------------------------- "Whether the authorities be invaders or merely local tyrants, the effect of such [gun] laws is to place the individual at the mercy of the state, unable to resist." - Robert Heinlein, in a 1949 letter concerning "Red Planet" -- The Next Challenge - Public Access Unix in Northern Va. - Washington D.C. 703-803-0391 To log in for trial and account info. ------------------------------ Date: 2 Dec 92 13:13:47 GMT From: "H.S. Doyle" Subject: NASA has 5 hand grenades still on the moon from Apollo missions Newsgroups: sci.space In article , pgf@srl03.cacs.usl.edu ("Phil G. Fraering") writes: > >In article <1992Dec1.213904.2097@sunspot.noao.edu>, >bbbehr@sunspot.noao.edu (Bradford B. Behr) writes: >> In article <1992Dec1.152624.3587@pixel.kodak.com> >dj@ekcolor.ssd.kodak.com (Dave Jones) wrote: >>>Wasn't there an Urban Legend to the effect that Armstrong & Co. were >>>issued .45 automatics just in case? >> >> Just in case of bug-eyed moon monsters or giant mutant space goats or >> secret Nazi bases? Not likely. It is quite possible that they had >> sidearms in the command module in case they splashed/crashed down in >> the wilderness somewhere and had to hunt for food or defend themselves >> from ravenous but terran beasts. > >Ordinary firearms wouldn't work in a vacuum anyhow. >The gunpowder couldn't burn. The same might be true at high >altitudes on the Earth's surface, as I've heard that in a >particular South American city (I think it was La Paz, Bolivia), >there's not enough oxygen in the air for them to really require >a fire department. Gun propellant powder doesn't need oxygen to burn, it will explode quite happily in a vacuum. The chemical reaction isn't an oxygen-carbon one. I thought this would have been obvious due to the fact that the powder in a cartridge goes off when the bullet is still in the cartridge case and thus blocking it from the air! Harry. ------------------------------ Date: 2 Dec 92 01:58:05 GMT From: Rich Kolker Subject: Shuttle replacement Newsgroups: sci.space.shuttle,sci.space In article <70145@cup.portal.com> BrianT@cup.portal.com (Brian Stuart Thorn) writes: >>By the way Henry, I found out some interesting stuff there are three versions >>of the Saturn V first Stage. These are as follows >> >>S1C-T Test Stage for Manufacturing and Ground firings >> This is the one at the Alabama Space & Rocket Center >> >>S1C-D Dynamic Test model. Was later scrapped at the end of >> the program. >> >>S1C-1,2,3.... Flight Saturn S1 C stages. >> > >I don't know the true designations, but I think that the S1C-D that you said >was scrapped is presently on display near the VAB at Kennedy Space Center. >It was part of the AS-500F vehicle used to test the Kennedy facilities in >1966. At least, I'm pretty sure that AS-500F is on display at the Cape. > >-Brian I checked this out a while back. The Apollo 19 Saturn is at KSC, the Apollo 20 Saturn is at JSC (I could check out the actual SV designations in Starges to Saturn, but you get the idea). The Saturn V at MSFC is the Engineering test model, not a flight article. ------------------------------------------------------------------- rich kolker rkolker@nuchat.sccsi.com It's been a long, long time -------------------------------------------------------------------- ------------------------------ Date: 2 Dec 92 02:14:19 GMT From: Rich Kolker Subject: Shuttle replacement Newsgroups: sci.space In article <1992Nov27.141645.24129@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: >In article henry@zoo.toronto.edu (Henry Spencer) writes: >>In article <1992Nov26.160614.19313@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: >>>>A bit less zenophobia please! what the hell do you think an airliner is? >>> >>>Something with *wings* on it. >> >>Just think of DC-1 as a high-performance helicopter. > >Even they have rotary wings. The reason I keep harping on this is that >landing *on* a ball of fire is too damn near landing *in* a ball of fire >for my tastes. I've been in a helicopter with in flight power failure; >I've been PIC of a fixed wing aircraft with in flight power failure; and >I walked away from both. I don't see any margin for error in setting down >on rocket exhaust. Either everything works perfectly and you survive, or >something fails and you topple over and burn, or if you're higher you >smack in hard and burn. > So long as your engines fire through the CG, the engine redundancy of DC-1 as currently planned (and understand the whole idea of X and Y is to change that paper design based on flight testing...like they do with aircraft) will not easily allow "topple over and burn" any more than a properly trained pilot will "spin out and burn" in a twin with an engine out. ------------------------------------------------------------------- rich kolker rkolker@nuchat.sccsi.com It's been a long, long time -------------------------------------------------------------------- ------------------------------ Date: 2 Dec 92 02:47:26 GMT From: Rich Kolker Subject: Shuttle replacement Newsgroups: sci.space In article <70618@cup.portal.com> BrianT@cup.portal.com (Brian Stuart Thorn) writes: >>Please dont confuse the re-entry phase from the landing hover phase. >>certainly a phine guidance error at re-entry results in hundreds of >>miles in terminal descent. but shuttle has that same problem and you >>dont seem to scream about that. the key point that DC-1 will have >>over STS is that when they punch out of the blackout zone they can >>get a guidance update from GPS,LORAN, Ground radar or visual and if they >>are significantly off course they cna look for a convenient emergency >>descent location and make a powered landing. > > The Space Shuttle no longer has a 'blackout zone'. The TDRS satellites > eliminated it. I don't know about the DC, but it probably will avoid > a blackout zone, too, if Mc-D leases TDRS space from NASA or something. > The space shuttle does too have a blackout zone. The Zone of Exclusion is over the Indian Ocean, and the exact size depends on shuttle altitude. In addition, the shuttle can be out of radio touch due to attitude requirements that block the Ku Band antenna. There is a blackout due to atmospheric ionization during reentry. Finally, during the entry after that point, there have been certain high inclination flights that, due to the approach path, have been out of comm range during much of the run across the US into KSC. ------------------------------------------------------------------- rich kolker rkolker@nuchat.sccsi.com It's been a long, long time -------------------------------------------------------------------- ------------------------------ Date: Wed, 2 Dec 1992 13:58:21 GMT From: "Allen W. Sherzer" Subject: Shuttle replacement Newsgroups: sci.space In article strider@clotho.acm.rpi.edu (Greg Moore) writes: >>Amounts to the same thing. Most of the Shuttle flights which have ever been >>scheduled have been cancled. That's not reliable service. > This comment bears a little explaining I think. What exactly has >beed cancled that has actually been scheduled... Check out the table in the Nov. 12, 1990 issue of Avation Week on Page 27. In ten years of operation this is the first year where Shuttle has gotten even close to projected flight rates. >However, if something DOES go wrong, or for some reason you want a >person on sight, then the shuttle wins. Maybe even not then. It depends on the cost of failure. >For something like Hubble, or >some other unique satellites, I'd prefer the Shuttle. One reason Hubble is unique is that Shuttle eats almost a third of NASA's budget. I hope you consider this when measuring Shuttle utility. If YOU where paying for Hubble, which would you pick? > Allen, they haven't made a profit in 6 years (since Challanger). Largely because they are forced to compete with government subsidized competition. The point still remains that the commercial providers are REDUCING the cost of access to space; Shuttle increases it. Commercial launchers spend investors money, Shuttle spends MY money. Given a choice between a cheaper option which costs me nothing and a more expensive one I need to pay for I would pick the former. How about you? >>But what would have happened if we developed a commercial based infrastructure >>back in 1980? Much furthur I'll bet. >Let's argue today, not the past. One thing we need to do to make progress is understand the mistakes of the past and then have the courage to correct them. Allen -- +---------------------------------------------------------------------------+ | Allen W. Sherzer | "A great man is one who does nothing but leaves | | aws@iti.org | nothing undone" | +----------------------143 DAYS TO FIRST FLIGHT OF DCX----------------------+ ------------------------------ Date: Wed, 2 Dec 1992 11:55:26 GMT From: Gary Coffman Subject: Shuttle replacement Newsgroups: sci.space Nonflamable materials only in this post. :-) In article <1992Nov30.011822.7870@iti.org> aws@iti.org (Allen W. Sherzer) writes: >In article steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes: > >>Now here's a question: How is the DC to be refuelled and reloaded >>between missions? That is, it won't necessarily land on a pad and it >>has no wheels (?) so how will the ground crew handle it? > >I believe current plans are to put weels on it after it lands and tow it >to a hanger or the launcher. Empty weight is only 80K pounds so this isn't >hard. What's the height/width of the projected DC? What I'm asking is how stable is this thing on just wheels? Would a bracing structure be helpful or required when moving it over ordinary rough concrete surfaces? >>Does it need a gantry to load heavy payloads or will a >>mobile crane be used? > >A mobile crane will be fine. Payload are put into a standard pallet and the >pallet has standard interfaces with the vehicle. This means that the complex >integration tasks can be done offline and payload/vehicle integration will >take a few hours at most. Max payload weight is 20K pounds so a mobile crane >is no problem. Are the payload/pallet integration costs included in DC flight costs, or are they offloaded onto the customer? Standards help, of course, but payload integration costs are a significant part of spaceflight costs. Also, I'd expect a mobile gantry platform would be better than having a ten ton pallet swaying on the end of a crane cable. Costs for a ten ton mobile gantry platform shouldn't be that high, just a glorified forklift. Gary ------------------------------ Date: Wed, 2 Dec 1992 01:04:18 GMT From: "Carlos G. Niederstrasser" Subject: Space probe to pass Earth Newsgroups: sci.space In article clarinews@clarinet.com (UPI) writes: > > PASADENA, Calif. (UPI) -- NASA's Galileo space probe will zip past > Earth and the moon next week to use the planet's gravity to fling it > toward an exploration of Jupiter beginning in three years, officials > said Tuesday. > ``We are now just one week from the Earth-II flyby, the gravity > assist, that will send Galileo to Jupiter,'' said project manager > William O'Neil during a briefing at NASA's Jet Propulsion Laboratory. > Galileo will pass within about 68,000 miles of Earth's moon at 10:58 > p.m. EST Dec. 7 and pass within 190 miles of Earth at 10:09 a.m. EST the > next day, he said. The pass will increase the probe's speed by 8,280 > mph, whipping it out toward the asteroid belt between Mars and Jupiter > at about 87,190 mph. > Scientists plan to use the pass by the atomic-powered, $1.4 billion > spacecraft to calibrate the probe's instruments by using the various > sensors and cameras to study and photograph the Earth and moon. 190 miles ?!?! Isn't that even closer than the normal shuttle orbit? Are they missing a few zeroes? I mean, at 190 miles I would expect air resistance (considering the high speed) to be quite detrimental. And on a 'whine' note, once again the press trying to scare ignorant fools by stating that the spacecraft is atomic-powered. Was that reference really necessary in the context of the article? I think not! -- --------------------------------------------------------------------- | Carlos G. Niederstrasser | It is difficult to say what | | Princeton Planetary Society | is impossible; for the dream of | | | yesterday, is the hope of today | | | and the reality of tomorrow | | carlosn@phoenix.princeton.edu |---------------------------------| | space@phoenix.princeton.edu | Ad Astra per Ardua Nostra | --------------------------------------------------------------------- -- --------------------------------------------------------------------- | Carlos G. Niederstrasser | It is difficult to say what | | Princeton Planetary Society | is impossible; for the dream of | | | yesterday, is the hope of today | ------------------------------ Date: 2 Dec 92 04:12:38 EST From: andrew busigin Subject: spherical space structure Newsgroups: sci.space DW> But spherical shapes for space stations aren't as efficient as you might DW> hope. The thickness of the material that would be required for DW> the wall of a sphere containing a 20 kPa (or whatever) pressure DW> increases with the diameter of the sphere. If I remember aright, DW> directly proportional to the diameter, so a sphere 100 metres in DW> diameter, say, would need walls twice as thick as a 50m sphere. DW> Thus the mass of material needed for the walls would be directly DW> proportional to the volume of the sphere, rather than increasing DW> more slowly as you might expect and hope. DW> DW> Oh well... Perhaps you should re-examine your assumptions on efficiency, David. There is no geometric shape with 1 - a more efficient ratio of volume to surface area, or skin mass, in the case of a hollow spheriod. 2 - a greater strength to mass ratio, for a container under pressure. 3 - a simpler method of erection than inflation. (Please Mr. Lurker, restrain yourself! ) The fact is that space station freedom is based on technology anchored in lego blocks and mechano sets. Nature tends to use sacs to contain pressure. Hmmm... Examination of the technologies deemed critical for Freedom, revealed that they felt that structural members needed to be extruded on site. This manufacturing technique, together with the spelunkers' dream castle architechture, creates a formidable amount of construction effort in open space. Spheres, on the other hand, might be manufactured on earth, a number at a time, as large as football fields, and shuttled up. Reinforcing and insulative materials would ride up compressed, ie - honeycomb, resins, foils, and applied to a surface from inside, and perhaps outside. As for pressure, the spheroid would initially probably be fabric based, perhaps related to tevelec. The thickness of the skin could be built up in the same fashion that a Harrier Jet's Wing is constructed, from advanced composites. As for the pressures involved, the spheroid could be initially inflated to 1psi, rigidized, the skin built up, and gradually pressurized to 10psi as another post'r suggested is required for the N2 O2 mix now thought proper by NASA. One final, very important note. Your reaction, "Oh Well...", is a problem. Ceative thought must be encouraged especially in the science and space conferences. Good science demands that problems be exposed to the light of reality. But good scientists, and engineers can usually find their way around problems. We have to get the youngsters out there thinking! Between all the people in these conferences, we ARE capable of BUILDING on new ideas, not just critiqueing them. BTW, I do appreciate your post. Best Regards, ------------------------------ Date: 2 Dec 92 06:12:12 GMT From: Robert Sheaffer Subject: STS-48 and "SDI": Oberg vs. Hoagland Newsgroups: sci.skeptic,sci.astro,sci.space,alt.alien.visitors I am posting the following file that I received from James Oberg, a well-known writer on the space program. He is discussing the same videotaped footage from NASA's STS-48 mission that has been endlessly showen as a supposed "UFO." Richard Hoagland, a major promoter of the "Face On Mars," claims that NASA cameras accidentally caught a secret "star wars test". Here is Oberg's rebuttal. James Oberg, Rt 2 Box 350, Dickinson, TX 77539 Re: Did STS-48 view a "Star Wars" test? The STS-48 mission was the 43rd shuttle launch, the 13th flight of OV-103 Discovery, with the Upper Atmosphere Research Satellite (UARS). The crew was John Creighton, Ken Reightler, Jim Buchli, Mark Brown, and Sam Gemar. It was launched from KSC Pad A at 2311GMT Sep 12, 1991 (twilight),landed at EAFB on Sep 18, 0738GMT (night), duration 5d08h27m. The orbit was inclined 57 degrees to the equator at an altitude of about 570 km, second only to the 616 km altitude of the Hubble deploy mission a year and a half earlier. Due to radar experiments with the deployed UARS satellite, I was present in the control room for two planning shifts (my job was as "Guidance and Procedures Officer" for actions related to orbital rendezvous, such as the planned checkout of the radar which had shown performance anomalies on several earlier missions). I have reviewed the videotape by Richard Hoagland alleging that the notorious STS-48 videotape shows a "Star Wars" weapons test against a target drone with astounding propulsion. In my judgment, the facts, analysis, and conclusions presented by Mr. Hoagland are entirely wrong. Is the object really very far away? Hoagland's argument depends on proving that the object is at or beyond the physical horizon, "1713 miles away". Proving this depends on optical analysis of the image and of its motion. All of Hoagland's analysis is invalid. First, Hoagland alleges that the videotape shows the object suddenly appearing at the edge of the Earth, as if it had popped up from behind the horizon. But a more cautious viewing of the tape shows this is not accurate. The object does NOT rise from "behind the horizon". It appears (arguably, it becomes sunlit) at a point below the physical horizon, just slightly below, to be sure, but measurably below the edge of the Earth (the "limb"). It has been suggested (Dipietro) that the object's sudden appearance is due to sunrise. This is plausible. I suggest a variation on this, that the object became visible when it moved up out of the shuttle's shadow just after sunrise. Since the video was taken near sunrise, the shuttle's shadow was pointing back nearly parallel to Earth's horizon, and the ground was still dark (bright ground reflection later lights up debris even if they are in the shuttle's sun shadow). This would require that it be close to the shuttle. The proximity to the horizon line would be coincidental. Note that the bright light in upper left is some sort of camera anomaly and is not an electronic horizon marker as alleged by Hoagland. There is no such thing as an electronic horizon marker. Is the object behind the atmosphere? Hoagland argues that analysis of the imagery shows the object is physically behind the atmosphere. But I disagree. It is NOT seen through the atmosphere: First, consider the brightening effect. Computer analysis is shown which alleges that the brightening of the object while below the airglow layer is analogous to the brightening of stars setting behind the airglow layer. This allegedly implies that the object, like the stars, is behind the airglow layer. This argumentation is false because it posits the wrong causation mechanism for brightening ("passage of the light through atmosphere"). This should be obvious since at the airglow altitude (40-60 miles) the atmosphere is already extremely thin and the lapse rate (the drop in pressure per rise in altitude) is already much reduced over the value at lower altitudes (that is, crossing the "airglow boundary" does NOT significantly change the atmospheric density the light ray is passing through). If density WERE the true cause of brightening, the effect would markedly peak at a lower altitude (as soon as the beam rose above total obscuration), then drop rapidly as atmospheric density dropped, and show NO NOTICEABLE CHANGE in dimunition rate as it crossed the airglow layer because the density of traversed air wouldn't change much either at that region. The actual connection for the object's brightening is the absolute brightness of the airglow layer in the background. The object is brighter when it is against a bright background, just as stars are brighter. This is not an effect of a light ray transiting the airglow region and somehow being strengthened. Instead, I believe it is an effect on the camera optics of the summing, pixel by pixel, of all brightness within the field of view. A bright object with a dark background will not throw as many photons on the individual pixels of the camera as would a bright object with a half-bright background. The camera's vidicon system will respond to light in the background by brightening the small point-source objects observed in that region, either lying behind or crossing in front of that background. Repeat: crossing in front of that airglow. This is confirmed by other checks. Observers can note that other drifting point-source objects, clearly starting well below the horizon line, also brighten as they traverse the airglow region. NOTE: Hoagland's argument that the dimming beyond the airglow disproves NASA's contention that the object is nearby and sunlit, since as it gradually rose "higher into the sunlight" it should brighten, not dim, is false. Once in full sunlight, no further brightening occurs. Sunrise only lasts as long as it takes for the sun (0.5 degrees wide) to rise above the horizon, at the orbital angular rate of 4 degrees per minute (that is, 360 degrees in a 90-minute orbit), which comes to just 7-8 seconds, which anybody should have been able to figure out. Of course this is different from ground rates, which depends for the sun's angular motion on earth's rotation rate (4 minutes per degree, 16 times slower than spaceship orbital rate). This argument reveals Hoagland's unfamiliarity with basic orbital flight conditions and implications. Notice that no mention is made by Hoagland of the clear absence of expected refractive effects of being behind the atmosphere. As is known by anybody who's watched sunset/moonset at a flat horizon, the atmosphere creates significant distortion in the bottom .2-.4 degrees of the image. The lowest layers demonstrate a vertical compression of 2:1 or greater. This is also shown on pictures of "moonset" from orbit. If the STS-48 object were really travelling nearly parallel to the horizon but somewhere behind the atmosphere, this would be visible by analyzing its flight path. As it rose its line of travel would markedly change as atmospheric refractive effects disappeared. This does not happen, which strongly suggests that the object is NOT behind the atmosphere. Since the arguments for great range to the object all fail, the conclusions based on angular motion converted to physical motion also fail. What is the "flare" in the camera that precedes the change in motion of all the objects? I believe the flare in the lower left camera FOV is an RCS jet firing, not per Hoagland an electromagnetic pulse effect. There are several reasons: it does not look like any known electromagnetic video interference; it looks just like previously seen RCS flares; and the Hoagland counterargument about an alleged need for pointing changing is not valid. First, while it is true that EMI can affect electrical equipment, such pulses would not lie in any localized region of a television screen but would blitz the whole image. Anybody whose TV has ever been blitzed by lightning knows that the effect does not confine itself to the corner nearest the lightning. Also, far more sensitive electronic equipment aboard the shuttle, including computers which were counting the pulses of individual cosmic rays striking their circuits, were not affected by the event (otherwise, the entire television transmission would have been knocked out). So Hoagland's explanation is magical and unrealistic. Second, the optical appearance of RCS jet firings is well known and familiar to experienced observers, and they look just like the flash in question. These have been observed and videotaped on every shuttle mission, from the crew cabin, from payload bay and RMS cameras, and from cameras on nearby free-flying satellites, and from ground optical tracking cameras as well. Third, Hoagland's argument that the line of travel of stars down to the horizon should have been kinked by the jet firing is plain ignorant. During attitude hold coast periods, the shuttle autopilot maintains a "deadband" of several degrees, slowly drifting back and forth and, when the attitude exceeds the deadband limit, a jet is pulsed to nudge (NOT "shove") the spaceship back toward the center of the deadband. The angular rates induced by these 80-msec pulses are as follows: ROLL .07 deg/sec PITCH .10 deg/sec YAW .05 deg/sec Note that the star motion would have changed direction ONLY IF the orbiter's pointing attitude was shifted to the right or left. If shifted up or down, only a slight change in star motion rate would occur (this appears to be the way the jet plume is actually directed) but so would horizon motion, so it would have to measured as absolute screen position. If shifted in or out, no change at all would be observable. This is all based on pure geometric considerations overlooked by Hoagland. After ten seconds, even in the worst case (pitch motion inducing pure crossways angular motion), the star track would only have diverged a single degree from the former straight line. This is visually undetectable on the images shown by Hoagland. So the fact that he sees no change in the star motion tracks does not disprove that the pulse was an RCS jet. Video Encryption: Hoagland alleges that since STS-48, all external STS video has been encrypted and will be viewed only after NASA review and approval. I have checked with a NASA Public Affairs official, and have personally verified, that things (as usual) are not quite what Richard Hoagland alleges. On STS-42, the second flight after STS-48 (the STS-44 DoD mission went between them), the International Microgravity Laboratory (Spacelab) science group requested that medical video imagery from the cardiological studies (sonogram images) be treated as privileged medical information, as all previous audio conversations with doctors had been. NASA discovered that having to continuously reconfigure the White Sands TDRSS site and the TDRSS satellites back and forth for encrypted video transmission was a laborous process. Rather than spend all that time, it was decided to go into encrypted mode continuously and decrypt the raw video at NASA Goddard for immediate release over the "NASA Select" circuit. Normally, when there was shuttle video, the White Sands to Goddard raw video link had been unencrypted, and the Goddard relay to "NASA Select" required no further processing; but when medically-privileged video was to be transmitted (a new innovation on STS-42, planned for years), complex encryption processes had to be initiated on the shuttle, on the TDRS satellites, at White Sands, and at Goddard. The procedure for constant encryption was implemented to avoid the cost of many switchovers between modes. But the NASA Select video from Goddard was to continue to be decrypted except for the medical transmissions, which were to be openly announced on the audio feed, just not piped into a million homes and schools nationwide. Since then, the NASA Select video (originating at NASA Goddard, and containing other sources of video, too) has continued to be transmitted as before, with the only change that the White Sands to Goddard link (which viewers could previously observe when it was active) is now encrypted. There is no hint from air-to-ground conversations that anything other than the new (and long scheduled) medical video imagery is being interrupted. And although it is encrypted, the White Sands raw feed can be observed to tell if there is a video signal or not on the feed, so I am told. Conclusion: The standing explanation, that the objects are near the shuttle, are sunlit, and are affected by the plume field of an RCS jet firing, remains valid. P.S. Hoagland made a number of other factually erroneous comments about live planetary image transmissions. He says that all previously NASA planetary probes transmitted live imagery. Actually, only fly-by probes did that, particularly the fly-by probes which had slow transmission rates which took many minutes to build up each image. Probes orbiting other planets (Venus and Mars, for example), do not (and I believe, never HAVE) transmitted live imagery, since they are frequently occulted by the planet's mass. Each orbit's imagery is stored and dumped over a short portion of each orbit, and the imagery data is initially decoded over the next hours and days. Live coverage of the actual image transmission would usually be blank, but for a few minutes every few hours would show images flipping across the screen at a very fast rate, if there was enough computer power to decode them in this "real time" speed. There is no practical reason why computers have to be built so powerful to keep up with the high- speed dump rate for a few minutes, then rest idle for the next several hours. Outside of avoiding whines about censorship, there's no reason to do so. -- Robert Sheaffer - Scepticus Maximus - sheaffer@netcom.com Past Chairman, The Bay Area Skeptics - for whom I speak only when authorized! "Mystical explanations are considered deep. The truth is that they are not even superficial." - Friedrich Nietzsche (The Gay Science: 126) ------------------------------ End of Space Digest Volume 15 : Issue 488 ------------------------------