Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from hogtown.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 ; Sun, 10 Feb 91 01:40:10 -0500 (EST) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sun, 10 Feb 91 01:40:04 -0500 (EST) Subject: SPACE Digest V13 #143 SPACE Digest Volume 13 : Issue 143 Today's Topics: MAJOR SOLAR FLARE ALERT - TWO EVENTS - 07 FEBRUARY Landsat Photographs Payload Summary for 01/17/91 (Forwarded) Galileo Update - 01/18/91 Payload Summary for 02/08/91 (Forwarded) GPS Satellite Gets 2nd Life Re: GPS Satellite Gets 2nd Life Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription requests, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- X-Delivery-Notice: SMTP MAIL FROM does not correspond to sender. Date: Fri, 8 Feb 91 01:38:47 MST From: std_oler%HG.ULeth.CA@vma.cc.cmu.edu (Cary Oler) Subject: MAJOR SOLAR FLARE ALERT - TWO EVENTS - 07 FEBRUARY X-St-Vmsmail-To: st%"space+@andrew.cmu.edu" -- MAJOR SOLAR FLARE ALERT -- FEBRUARY 07, 1991 Flare Event Summary Potential Impact Forecast -------- MAJOR ENERGETIC EVENT SUMMARY Two major flares erupted off the sun today. The first, rated a class M8.8/1F flare was spawned by departing Region 6471 (which has now rotated beyond view around the west limb). The flare began at 14:54 UT, peaked in intensity at 15:14 UT and ended at 15:40 UT on 07 February. The location of this flare was S10W86 and was associated with minor radio emissions. No sweeps were observed from this flare. The second major energetic event began at 21:18 UT, peaked in intensity at 21:23 UT reaching an x-ray level of M5.3 and ended at 22:46 UT. This flare was optically uncorrelated but is strongly suspected of being associated with departed Region 6471. Some significant radio emissions were observed from this flare, although no sweeps were detected. Radio emissions at 245 MHz reached 38,000 sfu. This flare was associated with a 1,900 sfu Tenflare at 21:20 UT, lasting 7 minutes. A third M-class event almost made the major-flare category today. At 17:12 UT, a class M4.9 x-ray flare (again, optically uncorrelated) was observed. However, unlike the second major flare, this event was not associated with any significant radio emissions or sweep frequency events. The effects from M-class flaring (and possible major flaring) may remain noticable for about the next 12 to 24 hours as Region 6471 continues to move beyond influential range. The effects of flaring behind the western limb will become unnoticable on 09 February. Other regions now worth noting are Regions 6480 (S10W15), 6484 (N14E25), and 6487 (N15E40). Region 6487 is perhaps the most newsworthy region currently visible. It has exploded in growth over the past 24 hours and has managed to spawn two low-level class M1 flares. This region is also the largest presently visible, now covering an area of 2,040 million square kilometers encompassing 22 spots within its boundaries. This region is presently holds a magnetic Beta configuration and is not regarded as a potential major flare producer yet. The optical configuration of this region is a type DKO group and has an angular extent of 8 degrees. The potential major flare warning remains in effect for 08 February. It will probably be cancelled on 09 February, unless the regions currently visible begin to exhibit potential major activity. The stratospheric warming alert remains in effect. Stratospheric warming is continuing over Siberia and is spreading polewards in the lower and middle stratosphere. The temperature gradient has reversed between 60 degrees north latitude and the pole. In addition, a weak mean zonal wind near 60 degrees north latitude is persisting. We are now into day 36 of this major stratospheric warming event. POTENTIAL TERRESTRIAL IMPACT PREDICTIONS Although flare activity was high today, none of the energetic events will have a terrestrial impact. A large polar coronal hole extension exists throughout much of the northern solar hemisphere. At the present time, the furthest southward extension of this hole occurs at N28W69, which appears to be the westernmost edge of the extension. No significant structural changes have been observed. However, grazing effects are possible. Geomagnetic activity is expected to increase to mostly Unsettled levels over the next two to four days. Auroral activity over high latitudes is likewise expected to increase. No significant auroral activity is expected over middle latitudes, although the notherly middle latitudes should witness the low to moderate auroral activity occurring over the high latitude zones. No geomagnetic or auroral storming is expected. ** End of Alert ** ------------------------------ Date: 8 Feb 91 03:30:05 GMT From: sun-barr!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!dsinc!bagate!cbmvax!amix!undrground!seanp@apple.com (Sean Petty) Subject: Landsat Photographs Does anyone know where (or if) any Landsat Photographs are available via anon FTP... Or better yet, is there a government office that makes these available (at a cost, of course!) ? I am interested in obtaining some of these, but am unsure where to start. Any help is greatly appreciated... Sean ---- undrground!seanp@amix.commodore.com ------------------------------ Date: 18 Jan 91 18:45:33 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: Payload Summary for 01/17/91 (Forwarded) Payload Status Report Kennedy Space Center Thursday, January 17, 1990 George Diller 407/867-2468 FTS 823-2468 TETHERED SATELLITE (TSS) STS-46/Discovery The Tethered Satellite has been undergoing receiving inspection and initial tests in an off-line laboratory of the payload Operations and Checkout building. Hardware associated with the TSS deployer is currently being integrated onto the pallet as well as integrating some associated experiments onto the mission peculiar support structure (MPESS). The first fit check of the satellite with the deployer is scheduled to occur Friday and will last about a week. A second fit check will also be scheduled for later this month or during February. GAMMA RAY OBSERVATORY (GRO) STS-37/Atlantis Yesterday the alignment of the spacecraft's two sun sensors was accomplished. Fueling of GRO for its on-orbit activity was completed late last last week as scheduled. A total of 4200 pounds of monomethyl hydrazine was loaded aboard (three to four times more fuel than is required by most spacecraft). This large quantity of fuel will permit extended mission operations. On Monday and Tuesday, work was performed to remove the spacecraft's test batteries and then reinstall the six nickel cadmium flight batteries which are housed in two modular power supply units (MPS). The MPS units were installed on the spacecraft yesterday and then the batteries were charged. Today the spacecraft is being powered up. The Instrument Switching Unit (ISU) which was removed on December 23, shipped to TRW, repaired and then retested, was reinstalled on the spacecraft yesterday. Integration and system tests are scheduled to start Friday. The ISU contains circuitry which controls electrical signals to various equipment throughout the Observatory. GRO is scheduled to be moved from its current location at the Payload Hazardous Servicing Facility (PHSF) to the Vertical Processing Facility (VPF) on Feb. 6 where final tests will be performed and work will be done to prepare it for integration with the Space Shuttle Atlantis. TDRS-E/IUS-15 (STS-43/Discovery) Final assembly, functional testing, and rf system testing of the Inertial Upper Stage for TDRS-E has been completed by the Air Force/Boeing test team on Cape Canaveral Air Force Station. IUS buildup operations are scheduled to be completed in mid-February. Due to possible limited availability of military aircraft given the current international circumstances, TDRS-E may be shipped early to KSC from the TRW plant in California. ------------------------------ Date: 18 Jan 91 18:57:30 GMT From: elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@decwrl.dec.com (Ron Baalke) Subject: Galileo Update - 01/18/91 GALILEO STATUS REPORT January 18, 1991 The status of the Galileo spacecraftas of end of day January 17 is as follows: o System Power Margin - 66 watts o Spin Configuration - All-Spin - cruise mode o Spin Rate/Sensor - 2.89rpm/star scanner o Spacecraft Attitude Sun Point Angle - approximately 1.7 degrees plus or minus 0.3 degree o Downlink telemetry rate/antenna - 40 bps (uncoded)/LGA-2 (Low Gain Antenna) o General Thermal Control - all temperatures within acceptable range o RPM (Retro Propulsion Module) Tank Pressures - all within acceptable range Yesterday on the Galileo spacecraft, the CDS "B" (Command Data Subsystem) memory copy activity was successfully completed; spot-check memory readouts indicated no anomalies or parity errors. Today, cruise science memory readouts were completed for the EUV (Extreme Ultraviolet Spectrometer), MAG (Magnetometer) and DDS (Dust Detector) instruments. In addition to the science readouts, a planned sun acquisition was successfully completed. A total of 2950 real-time commands have been transmitted to Galileo. Of these, 1557 have been pre-planned in the sequence design and 1393 were not. In the past week, a total of 149 real time commands were sent; 141 were preplanned and 8 were unplanned. Over the coming weekend, spacecraft activity will be limited to a planned radio science calibration on Saturday and a sun acquisition on Sunday. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ Date: 8 Feb 91 19:28:13 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: Payload Summary for 02/08/91 (Forwarded) GRO Status Report Kennedy Space Center February 8, 1991 George Diller 407/867-2468 FTS 823-2468 GAMMA RAY OBSERVATORY/STS-37 (Atlantis-April, 1991) The Gamma Ray Observatory began its 1-mile trip from the Payload Hazardous Servicing Facility to the Vertical Processing Facility (VPF) at 5:00 a.m. Thursday morning as scheduled. It arrived at the VPF air lock about one hour later and was moved into the high bay at 8:30 a.m. Work was completed by early afternoon to remove the protective covers and the anti-static liner over the spacecraft. Preparations are being made today for hoisting the Observatory into the west test cell. The actual crane operation is scheduled for Saturday morning. Next week, on Feb. 12 a two-day stand alone Observatory functional test will be conducted. The following week the integrated electrical tests are scheudled to start, beginning with the Interface Verification Test on Feb. 19 to verify the GRO's electrical compatability with the orbiter. The end-to-end test will follow on approximately Feb. 21 to verify communications between the Observatory and the Payload Operations Control Center at Goddard. The payload will go to the pad on or about Mar. 6. ------------------------------ Date: Sat, 09 Feb 91 12:27:29 AST From: Richard Langley Subject: GPS Satellite Gets 2nd Life PRN 9, one of the Block I GPS satellites, developed problems last December that have resulted in the loss of use of its momentum wheels. The GPS satellites are 3-axis stabilized by the use of these wheels. However, with the pressing need for the use of all available satellites for the Gulf war, the satellite controllers have ingeniously spin-stabilized the satellite. By spinning, the satellite acts like a gyroscope so that its spin axis (aligned with its antenna boresight) is more or less fixed in space. In this way, the satellite's antennas will point towards the earth for a period of time on each orbit, giving two useful periods of operation each day. The controllers have arranged the orientation of the satellite so that during one of these periods, the satellite is visible from the Gulf. On 8 February, PRN 9 was forecast to be usable from 05:30 to 07:30 UT when the satellite is visible from western North America, and 17:39 to 20:04 UT when the satellite is visible from the Gulf. These times should advance by 4 minutes each day. Another Block I satellite, PRN 6, is currently being switched off for two hours each day, from 08:00 to 10:00 UT, for some unknown reason. ============================================================================== Richard B. Langley BITnet: LANG@UNB.CA or SE@UNB.CA Geodetic Research Laboratory Phone: (506) 453-5142 Dept. of Surveying Engineering Telex: 014-46202 University of New Brunswick FAX: (506) 453-4943 Fredericton, N.B., Canada E3B 5A3 ============================================================================== ------------------------------ Date: Sat, 09 Feb 91 14:30:01 AST From: LANG%unb.ca@UNBMVS1.csd.unb.ca To: "NTP List" , CANSPACE@unb.ca, "Space Digest" , "Miranda Chin -- GPS Bulletin" , "TS Kelso" , "Carey Noll" , "James Stowell -- UNAVCO" , BUDDEN@MANTA.NOSC.MIL(REX A. BUDDENBERG) Subject: Re: GPS Satellite Gets 2nd Life On Sat, 09 Feb 91 12:31:00 AST Richard Langley writes: > Another Block I satellite, PRN 6, is currently being switched off for > two hours each day, from 08:00 to 10:00 UT, for some unknown reason. Seems that PRN 6 is in eclipse season and since its batteries and solar arrays have marginal performance, the transmitter shut down could be a power conservation move. ============================================================================== Richard B. Langley BITnet: LANG@UNB.CA or SE@UNB.CA Geodetic Research Laboratory Phone: (506) 453-5142 Dept. of Surveying Engineering Telex: 014-46202 University of New Brunswick FAX: (506) 453-4943 Fredericton, N.B., Canada E3B 5A3 ============================================================================== ------------------------------ End of SPACE Digest V13 #143 *******************