Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Wed, 2 Jan 1991 03:39:35 -0500 (EST) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Wed, 2 Jan 1991 03:38:55 -0500 (EST) Subject: SPACE Digest V12 #716 SPACE Digest Volume 12 : Issue 716 Today's Topics: Re: space news from Nov 5 AW&ST Heat loss through radiation NASA Headline News for 12/19/90 (Forwarded) Re: space news from Nov 19 AW&ST Galileo Update - 12/18/90 Re: MIR lottery (erh sweepstakes) Ulysses Update - 12/18/90 Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription notices, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: 19 Dec 90 19:04:29 GMT From: usc!elroy.jpl.nasa.gov!swrinde!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!dali.cs.montana.edu!ogicse!emory!emcard!wa4mei!ke4zv!gary@ucsd.edu (Gary Coffman) Organization: Gannett Technologies Group Subject: Re: space news from Nov 5 AW&ST References: <20699@crg5.UUCP>, , <20714@crg5.UUCP> Sender: space-request@andrew.cmu.edu To: space@andrew.cmu.edu In article <20714@crg5.UUCP> szabo@crg5.UUCP (Nick Szabo) writes: > >OSC and Hercules are the only U.S. aerospace companies since the >Shuttle to development a totally new, successful orbital launcher. >They did it for 1/50th (2%) of what it cost to develop the first Shuttle. >Unlike the major Shuttle contractors, they have carried a loss on the >project (in other words risked their own money) eying future commercial >markets. These are encouraging facts not gripes. Sorry I sounded like >such a sourpuss over such a happy event. :-) The fact that a little 400 kilo payload launcher cost 2% of what the vastly bigger and more complex shuttle cost is, in itself, shocking. What are the hard numbers on development costs? Gary ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: Tue, 18 Dec 90 22:32:32 EST From: John Roberts Organization: National Institute of Standards and Technology formerly National Bureau of Standards Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. To: space@andrew.cmu.edu Subject: Heat loss through radiation >From: ogicse!unicorn!n9020351@uunet.uu.net (james d. Del Vecchio) >Subject: Re: A human being in vacuum > dsr@mir.mitre.org (Douglas S. Rand) writes: >>Radiational cooling is pretty effective, especially when >>the surrounding black body temperature is 3 or 4 degrees K. If the >>person in the vacuum is in shadow they could probably freeze in just >>a few minutes. If they're in direct sunlight then they might boil on >>one side and freeze on the other (lots of fun). > -------- >I don't have a clear idea of how that would work. If the heat in your >body isn't going _into_ something (like air), then where is it going? As others have pointed out, heat loss would be through thermal radiation into "infinity". The rate of heat loss can be roughly calculated: The formula for energy transfer per second through heat flow for a "black body" (ideal) radiator is E = k * (T^4 - T0^4), where T is the temperature of the radiating body in Kelvins, T0 is the temperature of the surroundings, and k is 5.6696E-8 W / (m^2 * Kelvin^4). Therefore, the heat loss to open space of a blackbody object at 98.6 F would be about 520 W/m^2, at 40 F would be 335 W/m^2, at 0 F would be 240 W/m^2, and so on. I believe the effective radiating surface of a human body is about 1 to 1.4 m^2, and that a human is capable of generating at least 750 W for short periods of time, probably 200-300 W for extended periods, and perhaps 75-100 W at rest. It would seem then, that heat loss would be a problem. Mitigating factors: - The skin temperature is lower than the core body temperature, thus reducing heat loss somewhat. - If you were near a large warm object such as a spacecraft or a metal plate heated by the sun, then the solid angle of exposure to open space would be reduced, and again heat loss would drop. - You wouldn't be naked in space, or you'd better not be. Insulating clothing would reduce heat loss, as would the helmet material (transparent, but not at human thermal wavelengths). - Good reflectors make poor radiators, and vice versa. The above formula is for an ideal black, nonreflecting surface. You may have noticed that most manmade objects in space are painted brilliant white wherever possible. This reduces radiative heat loss in shadow, and also reduces heating in sunlight. (Most white surfaces actually have poor reflectivity at thermal infrared wavelengths, so the reduction in heat loss would not be too pronounced, but but I believe the energy in sunlight is mostly centered around near-visible wavelengths, so reduction of solar heating should be quite significant.) I suppose the underside of the Shuttle is black partly to help it radiate heat during atmospheric reentry. Radiative cooling can be observed on the earth. Air (except for the greenhouse gases) is not very good at blocking thermal infrared, so a clear night sky allows the surface of the earth to radiate heat into outer space very rapidly. (That's part of what makes amateur astronomy one of the coldest sports. :-) A cloud layer tends to reduce the cooling effect. The air doesn't radiate much infrared, so it may remain fairly warm while the surface gets cold. This effect has traditionally been used in the Middle East to produce ice even when the air temperature is above freezing. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: 19 Dec 90 20:53:49 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Organization: NASA Ames Research Center, Moffett Field, CA Subject: NASA Headline News for 12/19/90 (Forwarded) Sender: space-request@andrew.cmu.edu To: space@andrew.cmu.edu Headline News Internal Communications Branch (P-2) NASA Headquarters Wednesday, December 19, 1990 Audio Service: 202 / 755-1788 This is NASA Headline News for Wednesday, December 19, 1990 A new Office of Exploration and a new Office of Human Resources will be established within NASA, Administrator Richard H. Truly announced yesterday in a holiday message to employees. The creation of the two new offices was a rapid response to recommendations made by the Advisory Committee on the Future of the U.S. Space program. Truly noted that the initial duty of the Exploration Office would be to provide "well thought-out" options to meet the challenges of returning to the moon and and exploring Mars. The Human Resources Office would insure that NASA has the engineering, scientific and administrative talent necessary to fulfill its civil space mission. Truly also said that NASA would place considerable emphasis on initiating the committee's recommendation to develop a heavy lift launch vehicle and to insure the robustness of the U.S. civil space transportation system. * * * * * * * * * * * * * * * * * * * * * * * * * * Fog in Texas and Louisiana delayed this morning's takeoff of the Space Shuttle Columbia and its 747 carrier from Kelly AFB, San Antonio, Texas. Wheels up time for today's leg of the ferry flight to KSC was 9:44 a.m. Eastern time, with Barksdale AFB, Shreveport, Louisiana the planned next stop. A fly-over of the Johnson Space Center, Houston, was also planned. A weather front over the Florida panhandle make arrival time at KSC uncertain, and the possibility exists that an interim overnight stop at Eglin AFB, Florida, or at some other appropriate location may occur, due to weather. * * * * * * * * * * * * * * * * * * * * * * * * * * * Test firing of a modified Space Shuttle main engine has been tentatively rescheduled for 3:00 p.m. EST, Thursday, Dec. 20th, at Marshall Space Flight Center. Engineers said a problem with the test facility's computer during the final countdown caused the postponement of the test, originally scheduled for Tuesday afternoon, and they are still trying to determine the exact cause of the difficulty. The test is the first of a series to better understand the internal operating environment of the shuttle main engine. * * * * * * * * * * * * * * * * * * * * * * * * * * * At Kennedy Space Center, the Space Shuttle Discovery's right- hand OMS pod has been installed and its plumbing and electrical connections are being secured. Installation of the Forward Reaction Control system is scheduled for tomorrow evening. Carbon brake modifications on Atlantis are expected to be completed tomorrow. Here's the broadcast schedule for Public Affairs events on NASA Select TV. All times are Eastern. **indicates a live program. Wednesday, 12/19/90 12:00 noon Administrator's holiday message to employees 12:30 pm The Year In Review from NASA Centers 1:00 pm **Galileo Press Conference from JPL 6:00 pm Replay of Administrator's holiday message and The Year In Review from NASA Centers Thursday, 12/20/90 11:30 am NASA Update 2:00 pm **STS-35 Crew Post-Flight Press Conference from JSC All events and times may change without notice. This report is filed daily, Monday through Friday, at 12:00 pm, EST. It is a service of Internal Communications Branch at NASA Headquarters. Contact: CREDMOND on NASAmail or at 202/453-8425. NASA Select TV: Satcom F2R, Transponder 13, C-Band, 72 degrees West Longitude, Audio 6.8, Frequency 3960 MHz. ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: 18 Dec 90 03:46:33 GMT From: zephyr.ens.tek.com!tektronix!sequent!crg5!szabo@beaver.cs.washington.edu (Nick Szabo) Organization: Sequent Computer Systems, Inc Subject: Re: space news from Nov 19 AW&ST References: <1990Dec13.062441.16545@zoo.toronto.edu> Sender: space-request@andrew.cmu.edu To: space@andrew.cmu.edu In article <1990Dec13.062441.16545@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes: >... >US and Canadian electric utilities discuss rapid development and launch of >a solar-storm-warning satellite to help protect power-distribution networks >against high solar activity. The utilities fear possible repetitions >of the 13 March 1989 storm, which plunged Quebec into a nine-hour blackout, >nearly blacked out the entire US Eastern Seaboard as well, and caused >serious malfunctions and significant equipment damage in many areas. >A small satellite would be parked in a halo orbit around the Earth-Sun >L1 point [where ISEE-3 was stationed for some years]. It would be >quite simple, carrying a UCLA magnetometer and an LANL plasma analyzer. >The utilities hope that it could be up by 1992, given rapid commercial >development, launch on Pegasus, and commercial funding throughout. The >utilities hope that NOAA would contribute some money -- and indeed, both >NOAA and the USAF are interested -- but government budgeting is too slow >for the perceived urgent need. >... This is a great example of why lowering the entry-level costs of space by a factor of 5 -- even if the cost/kg is higher -- is a good business proposition. All of a sudden, we are seeing new industries emerge, in little niches here and there. Solar storm warning was previously a government monopoly for government purposes. Now, companies can afford to launch satellites to suit their own needs. Over the long term, IMHO the number of organizations with access to space will rise by an order of magnitude due to Pegasus. I predict that once consciousness of cheap space access reaches the business community, we will be seeing many more new, small industries like this one emerge. Not all of these will remain small. Way to go OSC and Hercules! -- Nick Szabo szabo@sequent.com "For historical reasons, this feature is unintelligible" The above opinions are my own and not related to those of any organization I may be affiliated with. ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: 18 Dec 90 20:48:15 GMT From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@ucsd.edu (Ron Baalke) Organization: Jet Propulsion Laboratory, Pasadena, CA. Subject: Galileo Update - 12/18/90 Sender: space-request@andrew.cmu.edu To: space@andrew.cmu.edu GALILEO STATUS REPORT December 18, 1990 Yesterday, the Galileo spacecraft successfully completed a 5-degree SITURN which resulted in the spacecraft leading the sun by about 2.5 degrees. In addition to the SITURN, the scan platform calibration activity was successfully performed. Today, the sequence memory load for TCM-9A (Trajectory Correction Maneuver) will be sent to the spacecraft. The TCM will be executed tomorrow and it is designed to change the spacecraft's velocity by about 5.3 m/sec. The resetting of the CDS (Command Data Subsystem) critical controller 2A POR (Power-On Reset) Telemetry indication will be performed today. This action was reported erroneously as being performed yesterday. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: 19 Dec 90 15:20:37 GMT From: swrinde!zaphod.mps.ohio-state.edu!ub!acsu.buffalo.edu@ucsd.edu (Maurice Volaski) Organization: SUNY Buffalo Subject: Re: MIR lottery (erh sweepstakes) References: <9012181903.AA00726@tilde>, <20773@crg5.UUCP> Sender: space-request@andrew.cmu.edu To: space@andrew.cmu.edu Yesterday's New York Times carried an article on the sweepstakes. One interesting statement made was that no one living in New York, Florida, or Rhode Island was eligible for the flight for legal reasons. Does any one know what law this is referring to? Maurice Volaski ------------------------------ Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Date: 19 Dec 90 18:56:18 GMT From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@ucsd.edu (Ron Baalke) Organization: Jet Propulsion Laboratory, Pasadena, CA. Subject: Ulysses Update - 12/18/90 Sender: space-request@andrew.cmu.edu To: space@andrew.cmu.edu ULYSSES STATUS REPORT December 18, 1990 As of 9 AM (PST), December 17, 1990, the Ulysses spacecraft is 42,947,521 miles (69,117,336 km) from Earth, and 388,420,334 miles (625,101,935 km) from Jupiter. The spacecraft is traveling at 75,539 mph (121,568 kph) relative to the Sun, and 34,970 mph (56,278 kph) relative to the Earth. On December 17, a further Conscan operation was carried out in telemetry Engineering Mode to make an accurate assessment of the actual hydrazine fuel usage. As Ulysses approaches Opposition, the Solar Aspect Angle is reducing which is in turn reducing the solar energy acting on the axial boom which is thought to be inducing the nutation-like motion. The axial boom will fall into complete shadow on about December 21. Routine operations have continued, with experiment monitoring and on December 12 a matrix re-configuration of the BAM (Solar Wind Plasma experiment) took place. Since the DSN (Deep Space Network) was able to provide virtually complete 24 hour coverage during this reporting period, no tape recorder operations have taken place. On December 18, further radio science testing will be carried out. On December 19-20, a GRU (Cosmic Dust) noise test will take place. Also on December 20, a STO (Radio and Plasma Wave) PFR command uploading together with radio science testing and KEP (Energetic Particles experiment) re-configuration will occur. KEP re-configuration will continue on December 21. The decision may be taken to switch off the S-band downlink on December 21. This will place the spacecraft in the foreseen routine downlink configuration. Following the Nutation Investigation Team meeting on December 18 further tests may be carried out to investigate the nutation-like behaviour. Since the DSN is able to supply almost complete telemetry coverage during the next reporting period, tape recorder operations are not foreseen. The DSN performance has been nominal during the reporting period. Extra support has been provided to maximize on the amount of real-time data acquired. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ End of SPACE Digest V12 #716 *******************