Two American launches and a Russian space walk top the week's news. A Proton launch that will bring the Iridium constellation to near completion was delayed twice during the week. The space station passed several milestones while Mars Global Surveyor has begun its interim science mission.
Highlights of the week of April 3 include:
Columbia is on Pad 39B awaiting its April 16 launch of STS-90 and the start of the Neurolab mission. The Flight Readiness Review has been completed and the Orbiter has been cleared for launch. Launch countdown will begin April 13 at 2 AM EST. The flight will be commanded by Richard Searfoss (Lieutenant Colonel USAF) and piloted by Scott Alman (Lieutenant Commander USN). Other crew includes Kay Hire, Richard Linnehan, Dave Williams, Jay Buckey Jr., and James Pawelczyk (NASA; Flatoday).
The Neurolab mission will study the effects of microgravity on the human brain and the nervous system. The sixteen-day flight is being billed as the most complex science mission ever undertaken on the Shuttle. In addition to the human crew, the Orbiter will contain the largest menagerie of animals sent into space. Neurological research utilizing these animals will help scientists understand how the nervous system develops and operates in a microgravity environment. Other studies will look at how the astronauts themselves adapt to the stresses of space. James Pawelczyk, a specialist in autonomic neurophysiology, will conduct four experiments on blood pressure regulation and orthostatic intolerance (Flatoday; NASA; SpaceCast).
While Mir cosmonauts Talgat Musabayev and Nikolai Budarin had some trouble opening the hatch locks, they left the station only fifteen minutes late on their April 1 spacewalk. Problems developed while attaching a handrail and a foot rest. At one point Musabayev accidentally switched off the power in his suit, but was able to turn it back on and continue with the mission. The work reinforcing the damaged solar panel was left undone when the walk was brought to a close by the limits imposed by the seven hours of air in the suit's tanks. Total duration of the spacewalk was 6 hours 40 minutes. During the space walk, astronaut Andy Thomas filmed the Russian pair from within the space station. Walks are scheduled for April 6, 11, 16, & 21 to stabilize the broken solar panel and to replace an orientation engine (AP; Chris v.d. Berg).
The Russian space agency has recently changed their policy towards journalists. Citing problems with the press exaggerating problems with the aging Mir station, the agency has restricted direct access to communications between the station and mission control. During the April 1 mission, audio feed available to journalists was intermittent at the control center. Instead, reporters were given periodic briefings on the progress of the space walk (AP).
Despite news that the station may be as much as $6 billion over budget, progress continues in the manufacture and integration of space station components and modules. Boeing recently delivered the last of forty remote power control modules (RPCM) that will be used in the US Lab. These multi-channel, high-power circuit breakers will provide fault protection and secondary power switching. Within the Lab will be twenty four racks--eleven devoted to power, and environmental controls and thirteen containing science experiments. The first of these, a 545-kg electrical supply rack was recently installed in the Lab. All eleven system racks will be installed before launch. The Lab will be shipped to Kennedy Space Center in August. The US Lab is currently slated to be launched on flight 5A in May of 1999. Six of the science racks will be installed in orbit during STS-99, the following flight (Boeing pr; NASA).
At 10:02 pm PST, March 30, a Delta II rocket was launched from Vandenberg AFB carrying five Iridium satellites. The launch was twice delayed due to unfavorable wind. The launch occurred with a five-second launch window. The successful deployment of the five 657-kg satellites around 80 minutes after launch brings the total number of Iridium satellites in orbit to fifty six--half of which were launched on Boeing Delta II rockets (Iridium PR; Boeing PR).
The launch of a Proton rocket carrying seven Iridium satellites has been delayed twice this past week. The most recent launch attempt on Friday was delayed due to electronic issues related to rainfall at the launch site. The launch has been tentatively rescheduled for no earlier than April 4 (Flatoday).
Last week's suspension of aerobraking occurred a little after 1:00 AM PST on March 27. At that point Mars Global Surveyor fired its engines at the high point of its orbit for 6.6 seconds. This caused the low point of the orbit to be raised from 125 km to 170.6 km. The new stable orbit is 11 hours and 38 seconds long. Later the same day during orbit 202, the science payload was activated, including the Magnetometer, Mars Orbiter Camera, and the Mars Orbiter Laser Altimeter. Two days later the Thermal Emission Spectrometer was activated. Aerobraking will resume Sept 11 and continue until Feb 1999 when orbital periods will be reduced to less than two hours (NASA).
Commercial usage of the Global Positioning System (GPS) will be improved by two additional civilian signals. Currently the GPS system produces two military and one civilian signal. The two new civilian signals will be added to improve positioning and timing services. Vice President Gore made the announcement Monday, March 30 that the second civilian signal will be in place by 2005. The seven-year lead time is necessary to build the additional signal capability into the next generation of GPS satellites (DOT PR).
Celcom (Malaysia) Sdn Bhd, an Orbcomm licensee has been authorized by the Malaysian Department of Telecommunications to provide full commercial service. This is the first such authorization outside the United States. Celcom will have exclusive rights to market Orbcomm services in Malaysia, Singapore and Brunei. Construction of ground-based infrastructure will begin in the second quarter of 1998 (Launch Space).
Orbcomm Global has also announced that it has signed a satellite service agreement with Loxley Public Company Ltd. of Thailand. Loxley will form an operating company named ORBCOMM Thailand. This marks ORBCOMM's thirteenth licensing agreement covering ninety-seven countries (ORBCOMM PR).
The USAF recently awarded Raytheon Systems Company a contract for the software sustainment and operations support of the USAF MILSTAR Extremely High Frequency satellite communications terminal, associated systems and facilities. The system has more than 120 fielded airborne and ground-based terminals. The initial contract is for $3.9 million but could rise to as much as $11.7 million with the exercising of options. The award dovetails with another $11.3 million contract awarded to Raytheon for the MILSTAR modem and processor upgrades. MILSTAR is a tri-service global communications system designed to provide strategic and tactical information while being highly resistant to a variety of threats (Raytheon PR).
The American Mobile Satellite company recently completed the acquisition of ARDIS--Americas largest ground-based wireless communications system. The move places American Mobile in a position to seamlessly integrate its satellite services with existing wireless communications services in order to meet accelerating market demands for wireless services. These services range from voice dispatch communications, two-way messaging, maritime and emergency response, and telemetry. The joined company has 80,000 subscribers with an income of $60 million (SpaceCast).
The FCC has granted E-SAT authorization for the construction, launch and operation of a constellation of six LEO satellites. The system has targeted automatic electric meter reading applications for utility companies initially in the US. E-SAT is owned by DBS Industries (20%) and by EchoStar (80%) (LaunchSpace).
The first SPOT-4 images were received on March 27 only three days after the craft achieved orbit. The images of the Danube River were transmitted to one of two receiving stations at Issus-Aussaguel. The on-orbit checkout is proceeding faster than anticipated which may allow the satellite to be declared operational earlier than the two months previously expected. The Spot Earth observation system was developed by the French space agency in partnership with Sweden and Belgium (LS).
President Clinton has established a panel to help resolve an interagency ideological dispute between the State and Commerce Departments concerning the export of commercial imaging satellites and related technology. National security is at the heart of the debate (Space News).
The population of space remains at the base line of three--all on board the Mir space station. The Mir crews include two Russians and one Australian-born US astronaut. This marks the completion of 3131 days of continuous human presence in space since the reoccupation of Mir on Sept 8, 1989. Only 87 days remain until the currently scheduled launch of the first element of the International Space Station. (http://uttm.com/space/statisti cs.html).
Dale M. Gray is a frontier historian working for GCM Services in Montana and Idaho. Frontier Status reports are a weekly annotated index chronicling progress of the emerging space frontier. Editorial assistance by Rick Bier. Timeline computation courtesy of Simone Cortesi. Send comments/corrections or subscription requests (subscribe FS or unsubscribe FS). Previous postings are archived at the Interglobal Space Lines web site.
(c) Copyright Dale M. Gray April 3, 1998.