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Sat-ND,
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"There was a technical glitch during the preparation for the launch," a spokesman for the Russian Space Agency was quoted as saying.
The launch from the Baikonur cosmodrome in Kazakhstan has been rescheduled for 0948 UTC on Friday. A Zenit-2 rocket is to put the Russian Resurs-O satellite and five smaller probes belonging to Australia, Chile, Germany, Israel and Thailand into orbit.
Hughes subsidiary DirecTV in a statement confirmed that a spacecraft control processor (SCP) aboard the DBS-1 satellite failed on July 4, 1998. "As designed, control of the HS 601-model satellite was automatically switched to the spare SCP and the spacecraft is currently operating normally. At no time did DirecTV's more than 3.7 million subscribers experience any loss of service," the company said.
"In the event that the back-up SCP on-board DBS-1 should also fail, DirecTV would immediately switch most of the affected programming services to the DBS-2 and DBS-3 satellites, which are collocated with DBS-1 at 101 degrees West. In addition, DirecTV continues to actively pursue other satellite back-up and fleet expansion strategies consistent with its long-term business plans," the statement went on.
DirecTV's problem followed a June 13 incident in which the primary control processor of Galaxy VII failed, causing service problems for several cable-television networks over several hours before the the backup processor was activated. Sat-ND has learnt that there was a power problem first, causing some C-band transponders to go off-line. When commanded back on, Hughes engineers reportedly found that the primary SCP was gone. That sounds just like electrostatic discharge caused by increased solar activity, which by the way has killed some birds (for instance Telstar 401) and partly disabled others (Tempo.)
In a conference call, Hughes told analysts that the problem might be rooted in processor wiring, and that electrostatic discharge from increased sunspot activity might be a contributing, though probably not a primary, factor.
On May 19, a similar failure occurred on Galaxy IV which had more severe consequences. The spacecraft went out of control after the backup SCP failed, knocking out service for as much as 85 percent of pagers in the USA. All three satellites are Hughes HS 601 models.
Of course, it's time for the inevitable 'analysts' again. Take for example a certain Vijay Jayant, analyst at Bear, Stearns & Co who noted that "PanAmSat has a huge exposure to Hughes-built HS 601s." So have other satellite operators--the HS 601 is the world's best-selling satellite.
"There's a concern that the HS 601s are failing about halfway through their 12-to-15-year lifespan." The concern seems rather unfounded as so far just one HS 601 has completely failed before reaching the end of its operational life, and that's Galaxy IV.
As a matter of fact, there are many satellite operators around the world who are not obliged to notify the public of important developments such as equipment anomalies. Personally, I think that many satellites actually do run on some backup system or another, starting of course with the travelling wave tube amplifiers. It is absolutely normal for a satellite to end its life with less operational transponders than there were when it took up service. It is also normal for the solar arrays and the on-board battery to get less efficient over the years.
It is, of course, a bit different with SCPs--if they fail, they fail completely but that's why there is a spare SCP on board. Same applies to other on-board systems. "We now have 82 active satellites in orbit, of which 35 are 601s," said Steven Dorfman, vice chairman of Hughes. "So when you have that many satellites in orbit working 24 hours a day, seven days a week, you have incidents, and that's why you have redundancy." It should be added that those spacecraft have to function in an extremely hostile environment.
Another analyst was quoted as saying that the failure of the same component on three satellites in three consecutive months "is too much of a coincidence to write off to a set of bad circumstances." Yes and no--it's a bit naive to think other satellite operators didn't experience similar troubles. As I said, don't expect them to tell the public unless they have to.
However, there actually seems to be a problem with Hughes' HS 601. According to Dorfman, "It's definitely a hardware problem on the satellite." The processor failures all "exhibit the characteristics of a short-circuit."
As could be expected, the latest problems with the Hughes 601 SCP were also the reason for the delay of the Galaxy X launch. Hughes will replace certain processor components on the satellite due to be launched August 3. Dorfman said the changes were intended to prevent a recurrence of the processor failures.
"It's the first time we had ever had a backup satellite in place. Without such a satellite, we would have had to wait as much as 12 to 15 months to get a launch time slot," said Gerald Dittberner, GOES programme manager at the U.S. National Oceanic and Atmospheric Administration. [In a similar case, they borrowed a European Meteosat.]
Normally there are two GOES satellites in use. GOES-10 was launched earlier and since then has been kept as an in-orbit spare.
The NOAA-15 spacecraft will improve weather forecasting and monitor environmental events around the world. NOAA-15 is the first in a series of five polar-orbiting satellites with improved imaging and sounding capabilities that will operate over the next twelve years.
NASA engineers successfully performed a series of over 300 on-orbit verification tests since the May 13, 1998 launch to establish a satellite performance baseline designed to characterise all aspects of instrument and spacecraft operation. The resulting information provides NOAA with a database to support product development and performance monitoring during the operational phase of the mission. This same data provides NASA with valuable insight into overall spacecraft subsystem and instrument interaction, so that enhancements and/or ground test modifications may be applied, if appropriate, to the follow on satellites, NOAA-L, M, N, and N Prime.
More information on the polar-orbiting programme can be found on the Internet at:
http://poes2.gsfc.nasa.gov/
and
http://www.2.ncdc.noaa.gov/doc/intro.htm
The hard-line Islamic Taleban militia will probably not ban radio as the decree, which also comprises satellite dishes, was announced on Radio Shariat. "These video recorders and television are the cause of corruption in this society," said Mohammed Qalamuddin, deputy head of the Taleban's Religious Ministry. [Not only in that society.]
Anyone who defies the ban will be punished in line with Islamic law, although Qalamuddin didn't specify what that might be. [Usually it's something like a hand, or something else, being chopped off; or being buried under a brick wall.] The ban is rather logical as the country's only TV station was shut down in 1996.
The BBC news site quoted correspondents as saying hundreds of households still secretly watch television through satellite dishes made from bicycle wheels, cooking pots or electric fans. [Up to you to believe that.] In addition, Indian and Japanese videos were being smuggled into the country--a practice that so far seems to have been tolerated.
Apart from that, here's a bit of Afghan folklore: Women must wear the all-enveloping burqua. They must not work, girls must not attend school. First floor windows should be paibnted black so the women inside cannot be seen from the outside. Men are beaten if they trim their beards. Most forms of light entertainment and music other than religious music are outlawed.
Now really, my dear friends in the U.S.: wouldn't it have been better to let the Russians stay in Afghanistan back in the early eighties instead of supporting the so-called "freedom fighters" of the Taleban? Just wondering. At least, you would've been able to export some TV programming to Afghanistan nowadays.
Oh well, and this is not exactly what I would call unbiased Anglo-Saxon journalism anyway: http://news.bbc.co.uk/hi/english/world/south_asia/newsid_128000/128921.stm
A review by the National Security Agency found no evidence of wrongdoing by Chinese authorities: "It is highly unlikely that the devices survived the crash because of the crash impact and high temperatures produced by burning rocket propellants." However, from earlier reports it looks as though some parts of the satellite were indeed found in a state that at least allowed for their identification.
US officials told a congressional hearing last month that Chinese authorities had stolen the circuit boards after the Chinese rocket carrying the US$200-million Intelsat 708 exploded in mid-air and crashed in February 1996.
For five hours after the crash U.S. officials were not allowed near the wreckage, arousing suspicion. However, most of the up to 200 people who got killed following crash died of poisonous gases and not of the direct impact of debris--which casually explains why the crash area had to be sealed off for five hours.
"Call this whatever you want, but it hardly qualifies as a success story in the making"--that's how Commerce Committee chairman Sen. John McCain summarised the hearing.
"We face problems beyond our control," said Gregory Schmidt, general counsel of LIN Television Corp., who was testifying on behalf of the National Association of Broadcasters. "Cable carriage of digital TV is uncertain at best and consumers' purchase of digital TV sets will be frustrated by uncertainty about these sets working with cable and about their ability to receive and display DTV (digital TV) signals, both via cable and over-the-air."
The problems seem to be mainly in the area of High-Definition TV (HDTV) broadcasting [probably because there's no real demand for it anywhere.] It will be possible with DTV which allows for up to six usual channels or one HDTV channel broadcast via a terrestrial TV transmitter, but early HDTV sets will not be able to connect to cable boxes or digital VCRs.
The problem is of course that HDTV are still quite expensive. Too expensive even for 'early adopters' actually, if they can receive just a few terrestrial channels.
Another problem is that cable systems might be required by law to carry all digital programming as well in addition to analogue 'must carry' channels. For some years, both technologies will co-exist, which could lead to a shortage of space that might result in dropping cable-only channels.
"If we don't do it right the first time, I think the technology will fail," warned Montana Republican Sen. Conrad Burns. [And I hope so.]
Business segments to be combined in the Motorola Communications Enterprise include cellular, space, land mobile, and messaging, information and media, which together accounted for about two-thirds of Motorola's $28.9 billion in sales in 1997. The remaining third of Motorola's 1997 sales were from its Semiconductor Products Sector and Automotive, Component, Computer and Energy Sector.
"Our recent financial results highlight the need for change in our communications businesses," said Christopher B. Galvin, Chief Executive Officer of Motorola.
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