Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from corsica.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl) (->ota+space.digests) ID ; Sat, 24 Jun 89 00:26:49 -0400 (EDT) Message-ID: <0Yckpuq00UkVIHzU4A@andrew.cmu.edu> Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sat, 24 Jun 89 00:26:35 -0400 (EDT) Subject: SPACE Digest V9 #507 SPACE Digest Volume 9 : Issue 507 Today's Topics: Re: Orbital Queries * SpaceNews 19Jun89 * Re: Outer Space Committee Jonathan's Space Report, forwarded Computers for the space station ---------------------------------------------------------------------- Date: 18 Jun 89 20:08:02 GMT From: att!tsdiag!ka2qhd!kd2bd@ucbvax.Berkeley.EDU (John Magliacane Wall Township NJ) Subject: Re: Orbital Queries References: <17665@louie.udel.EDU> Orbital inclination determines the apparent "direction" an earth satellite will move when viewed on a map of the world. Orbital inclination is defined as the angle between the orbital plane of a satellite and the equatorial plane of the earth (the equator). The inclination can vary between 0 and 180 degrees. A spacecraft will appear to move west-to-east if its orbital inclination is between 0 and 90 degrees, while a spacecraft having an orbital inclination between 90 and 180 degrees will appear to move east-to-west. For example, the US Space Shuttles are usually launched into orbits having inclinations between 28.5 and 57.0 degrees, and appear to move from west-to- east, while OSCAR-11, an Amateur Radio communications satellite, appears to move from east-to-west, since its orbital inclination is 98 degrees. Another interesting point to note is that US Space Shuttles are ALWAYS launched toward the East (over the Atlantic Ocean). This is the same direction as the Earth's rotation. Therefore, the Earth gives the Shuttle an extra "push" into orbit. Launching from the West coast would take a LOT more energy and fuel. Also, the minimum orbital inclination of a Shuttle mission is 28.5 degrees -- the latitude of the Kennedy Space Center. This orbit is generated if the orbiter is launched due East. If the Shuttle is launched either slightly North OR South of due East, then the inclination is ALWAYS greater than 28.5 degrees. -->> John A. Magliacane <<-- -- UUCP : ucbvax!rutgers!petsd!tsdiag!ka2qhd!kd2bd PACKET : KD2BD @ NN2Z (John) ..."There is no expedient to which a man will not resort to avoid the real labor of thinking." ....Sir Joshua Reynolds. ------------------------------ Date: 18 Jun 89 17:18:15 GMT From: att!tsdiag!ka2qhd!kd2bd@ucbvax.Berkeley.EDU (John Magliacane Wall Township NJ) Subject: * SpaceNews 19Jun89 * Bulletin ID: SPC90619 --------- SpaceNews --------- MONDAY JUNE 19, 1989 SpaceNews originates at KD2BD in Wall Township, NJ, and is distributed weekly around the world. It is available for UNLIMITED distribution. * OSCAR-9 NEWS * ---------------- It looks like OSCAR-9 will NOT be taking any CCD pictures for some time. A revised operating schedule was recently issued for OSCAR-9. Diary software reloads will still take place on Tuesdays. Digitalker telemetry will follow. The telemetry channels currently being downlinked via the Digitalker include: 08 : Battery Pack A Temperature (C) 18 : Battery Pack B Temperature (C) 22 : Battery Voltage +14V (Volts) 29 : Spacecraft -Y Facet Temperature (C) 35 : 145 MHz Beacon Output Power (UnCalibrateD) 39 : Spacecraft +Y Facet Temperature (C) 49 : Spacecraft +Z Facet Temperature (C) 59 : Spacecraft -Z Facet Temperature (C) From Thursday at around 12:00 UTC, the spacecraft will transmit the following sequence of data at 1200 bits/second: Telemetry : 60 seconds News Bulletin : 60 seconds Whole Orbit Data (WOD) : 150 seconds This will continue until 06:00 UTC on the following Tuesday when the beacon will switch off to help facilitate a software reload. The recent solar flare has greatly increased OSCAR-9's orbital decay rate. This means OSCAR-9 will come into range a few minutes before your predicted times of AOS. Here is element set 588 for UO-9 as issued by NASA on 13Jun89: Epoch : 89 161.08290495 Incli : 97.5527 RAAN : 214.2327 Eccen : 3.717E-04 ArgPer : 153.8947 MeanAn : 206.2960 MeanMo : 15.59543431 Decay : 8.6255E-04 RevNum : 42788 * UoSAT-D NEWS * ---------------- Harold Price, NK6K has been performing some performance tests on the UoSAT-D PCE, the Microsat CPU, and other machines. The results are summarised below. Using a dhryston C benchmark from Sept. '86 DDJ p.88, here are some performance numbers (using a 6MHz AT as the index). The same compiler and options were used (/AS /Ze /Zp /Ot /Gs ). /Gs (no stack checking) was used because the S/C stack check is different than the dos version. Normally /G1 (80186 instruction set) would be used for S/C programs. The RIC is the PC card we're using for the simulator and for SW development. Device CPU Clock dhrystons/sec index Toshiba 3200 80286 12 MHz 3762 2.03 AT Clone 80286 8 MHz 2145 1.16 IBM AT 80286 6 MHz 1850 1.00 UoSAT PCE 80C186 7.3728 MHz 1398 + 0.75 RIC 80186 7.3728 MHz 1391 + 0.75 AMSAT proto V40 7.372 MHz 861 0.47 AMSAT flight V40 4.608 MHz 538* 0.29* IBM PC 8088 4.77 MHz 1531 0.29 + The timer resolution of 10ms gives an uncertainty of +/-14 counts, these numbers are equivalent. * calculated based on clock speed difference from wirewrap. The RIC, Microsat Prototype, and UoSAT tests were done under the kernal, so clock and scheduler overhead are included. Zero wait states were used. [Story via OSCAR-9] * OSCAR-11 NEWS * ----------------- A new binary dump format is now operating in the Forth Diary cycle. The general format of the packet is as follows: Sync 1 - 50H Sync 2 - 41H Frame Count MSW Frame Count LSW ...64 bytes of data... Checksum MSW Checksum LSW - 16 bit addition of all bytes excluding syncs. This data is transmitted for 15 seconds after the news bulletin, between the Single Event Upset (SEU) dump and the Whole Orbit Data (WOD) dump in the current schedule, and contains engineering data. It is anticipated that WOD using this "packet" format will be introduced into the Diary schedule soon. * OSCAR-13 SCHEDULE * --------------------- Date : 14Jun89 until 16Aug89 | 16Aug89 until 16Nov89 Attitude: 180/0 | 210/0 Mode-B : MA 0 to MA 110 | MA 3 to MA 160 Mode-JL : MA 110 to MA 145 | MA 160 to MA 200 Mode-B : MA 145 to MA 255 | MA 200 to MA 240 OFF : % | MA 240 to MA 3 Mode-S : MA 150 to MA 160 | MA 210 to MA 222 Also, for a trial period the OMNI-directional 70cm antenna will be connected to the Mode-B RCVR from MA 20 to MA 40. These changes have been introduced to enable stations who have access around perigee to experiment with perigee operation. Mode S unchanged. 14May89: BLON/BLAT 212.0/+2.4 with a drift rate of 0.016/-0.061 deg/day, respectively. Transponders will be in operation during the whole orbit from June 14 until Aug 16 due to excellent sunangle and power budget. No perigee operation between August and November due to perigee solar eclipses! * FEEDBACK WELCOMED * --------------------- Feedback regarding SpaceNews can be directed to the author (John) via any of the following paths: UUCP : ucbvax!rutgers!petsd!tsdiag!ka2qhd!kd2bd PACKET : KD2BD @ NN2Z * SOURCES * ----------- Some of the news contained in this SpaceNews issue was obtained via OSCAR-9, OSCAR-11 and the KA2QHD and NN2Z PBBSs. * AMATEUR RADIO: A Natural Resource * -- UUCP : ucbvax!rutgers!petsd!tsdiag!ka2qhd!kd2bd PACKET : KD2BD @ NN2Z (John) ..."There is no expedient to which a man will not resort to avoid the real labor of thinking." ....Sir Joshua Reynolds. ------------------------------ Date: 19 Jun 89 14:59:36 GMT From: bunny!hhd0@husc6.harvard.edu (Horace Dediu) Subject: Re: Outer Space Committee In article <610774.890618.KFL@AI.AI.MIT.EDU>, KFL@AI.AI.MIT.EDU ("Keith F. Lynch") writes: > > The Committee on the Peaceful Uses of Outer Space ... > > With China, the USSR Cuba, and other butchers as members. Right. And Romania too, holy cow! The bandits of the world telling us how to behave! > I hope the US isn't involved. > ...Keith Me too. -- Horace Dediu Goodbye, cruel world. GTE Laboratories (617) 466-4111 #cd /;rm -Rf * & 40 Sylvan Road UUCP: ...!harvard!bunny!hhd0 Waltham, MA 02254 Internet: hhd0@gte.com or hhd0%gte.com@relay.cs.net ------------------------------ Date: 15 Jun 89 18:10:31 GMT From: usc!orion.cf.uci.edu!uci-ics!zardoz!tgate!ka3ovk!drilex!axiom!linus!alliant!merk!spdcc!ftp!poopsie!seth@apple.com (Seth D. Hollub) Subject: Jonathan's Space Report, forwarded Jonathan's Space Report Jun 15, 1989 (no. 18) Hello again girls and boys, I'm semi-back! We still dont have the usenet back after our system upgrade, so I'm asking a friend to post this. I wont see the net for another week or so, so email me questions rather than post them. --------------------------------------------------------------------- OV-102 Columbia due to be moved to the VAB on Jun 29 Launches: I'll be chronological for a change... USA-37, launched May 10 by Titan 34D/Transtage, is a Vortex telemetry intelligence satellite according to AvLeak, rather than a pair of comsats as reported earlier. It is now in geostationary orbit. Kosmos-2020, launched May 17 by RN Soyuz from Baykonur, is a GRU recon satellite expected to remain in orbit until mid-July. Kosmos-2021, launched May 24 by RN Soyuz from Plesetsk, is another GRU recon satellite, probably a Vostok-class payload, and probably landed around Jun 7. Meanwhile, Kosmos-2019 landed on May 18 after a 13 day flight. The first Resurs-F satellite, launched May 25 also by RN Soyuz from Plesetsk, is another Vostok-class payload, this time for earth resources photography. The data is used by the 'Priroda' center. Other satellites in the same series have flown under the Kosmos name, like Kosmos-2000 earlier this year; civilian applications are slowly being declassified and removed from the Kosmos series. Pravda reports that two separable 'Pion' air density research subsatellites were carried into orbit with Resurs-F. The satellites, built by students at the Korolev Aviation Institute in Kubyshev, have not yet been catalogued by NORAD. Three GLONASS navigation satellites, Kosmos-2022,2023,2024, were launched on May 31 by RN Proton from Baykonur into 19000 km orbits. Yet another recon satellite, Kosmos-2025, orbited Jun 1 from Plesetsk; no details yet on Kosmos-2026 launched Jun 7. The first launch of the 44L version of Ariane 4 was successful on Jun 5. The payloads were Superbird 1, a commercial Japanese comsat, and Kopernikus/DFS, a West German TV (Deutsche FernSehen) satellite. Jun 8 saw the launch of the 38th Molniya-3 satellite by RN Molniya from Plesetsk, into a 12 hour elliptical orbit. The second Delta II launch finally got off the ground on Jun 10, from pad 17 at Cape Canaveral, placing a USAF Navstar navigation satellite (USA-38) in orbit. Finally, on Jun 14 the first Titan IV was launched from pad 41 at Cape Canaveral, carrying the first of a new generation of early warning satellites toward geostationary orbit. .----------------------------------------------------------------. | Jonathan McDowell | phone : (617)495-7144 | | Center for Astrophysics | uucp: husc6!harvard!cfa200!mcdowell | | 60 Garden Street | bitnet : mcdowell@cfa.bitnet | | Cambridge MA 02138 | inter : mcdowell@cfa.harvard.edu | | USA | span : cfa::mcdowell | | | telex : 92148 SATELLITE CAM | | | FAX : (617)495-7356 | '----------------------------------------------------------------' -- "Segments: Just Say No!", "Whadya mean there's no control key?" seth@vax.ftp.com, ...ftp!poopsie!seth, 18 Rindge Av, Camb. Ma, 02140 USA Earth ------------------------------ Date: Mon, 19 Jun 89 15:06:47 EDT From: John Roberts Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. Subject: Computers for the space station There is at least one reason to hope that the "PC compatible" machines will not be the ones in charge of critical functions such as life support. In the past, NASA has tended to use specialized custom computers in its spacecraft, with one result being that they pretty much had control over any software that the machines could use. In the PC world, there are hundreds or thousands of people hard at work writing and spreading software to damage or scramble PCs and their memory systems. In the scenario described earlier, one of the astronauts smuggles aboard a copy of "Star Trek" downloaded from a BBS, which contains a virus. Or someone gets the bright idea that the station computers should be linked via radio to a terrestrial network, from which they are attacked by a worm. The interconnectivity of the proposed computers implies that a virus on one machine could propagate its effects to all the other machines. Imagine the astronauts finding out that their system has crashed, and having to wait several hours for a reboot before they can adjust their atmosphere (though there are hopefully manual overrides for such situations). Alternatively, suppose a robot arm holding a long, heavy rod goes berserk and starts flailing it around until it punches a hole through a wall. Of course, it may be possible to guard against such occurrences by stringent safeguards to prevent the introduction of harmful software. There have been several complaints about the choice of the Posix operating system, on the grounds that it would be an exotic and expensive system, and "plain old Unix" would be just as good. As I understand it, Posix is just an attempt by the federal government, in light of the many operating systems and many versions of Unix available, to come up with a standard which can be specified in procurement orders, so the users will know what they are getting. It is generally expected that within a few years, most or all government computer orders for Unix-like operating systems will include Posix specifications, so from this viewpoint it makes sense for the space station computers to be expected to meet this standard. In the debate on the choice of Ada for much of the software, I would like to point out that saying "Ada is undesirable because not many programmers I know program in Ada" is not entirely reasonable, because Ada is a young language, and because not many programmers write software for the applications that are the strong points of Ada. It has been claimed that a major purpose behind the creation of Ada was to produce reliable software for real-time control in a multiprocessor environment. If so, the space station should be a nearly ideal environment for the use of Ada, assuming the computers are used largely to control experimental processes. Though the speed and space efficiency of the earliest compilers and compiled code were not impressive, they have continued to improve, though it is not clear how far this improvement can go. Dale Amon writes: >...ADA is probably a mistake. ...Object oriented languages are the way the >(non-government) world is going. I have talked with several people who have studied Ada, and they claim that object oriented programming is one of the major points of emphasis in the design of the language. There is a set of articles in the June 1 issue of Computer Design describing changes in military procurement of mil-spec and off-the-shelf equipment and relevant issues, plus the evolution and current status of Ada. Incidentally, one application for which rapid response would be desirable is maneuvers to avoid known large pieces of debris in orbit. Are there any proposals on this subject? I presume the simplest approach would be to use earth-based tracking and computers to decide when there might be a hazard. Low earth orbits continually change due to atmospheric drag, so periodic inspection will be necessary in any event. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ End of SPACE Digest V9 #507 *******************