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Success of solar sail launch unknown BY STEPHEN CLARK SPACEFLIGHT NOW Posted: June 21, 2005 Update for June 22 @ 1 a.m. EDT: Mission controllers revealed a short time ago that weak blips of data believed transmitted from the Cosmos 1 spacecraft have been found in recordings at tracking station passes immediately after launch. The Planetary Society originally said that no signals were heard. If the new revelation is true, it suggests that the solar sail did reach some sort of orbit around Earth despite what Russian media reports indicate was a rocket engine problem during ascent. However, the U.S. military's space tracking network has not found the craft and its current orbit is unknown. "So now we search. It could take days to find," the Society said in a statement. Below is our earlier story based on information as provided following the launch:
Russian sailors launched the world's first solar sail from a nuclear submarine today, but the Cosmos 1 craft went missing a short time later and has not been located in orbit. Russian news services reported the rocket's first stage experienced an engine problem, suggesting that the sail either shot into the wrong orbital perch or never achieved orbit at all. The Volna rocket -- a converted ballistic missile -- blasted out of its launch tube aboard the Borisoglebsk at 1946 GMT (3:46 p.m. EDT). The Russian Navy submarine was stationed underwater in the Barents Sea offshore Russia's northern coast. The Planetary Society responsible for the mission provided online updates as reports came into their project operations center in Pasadena, California, this afternoon. The day began with nervous optimism, but that evolved into frustration and confusion following the launch. Officials had set up two portable UHF communication stations at Petropavlovsk on the Kamchatka peninsula in far eastern Russia and on the island of Majuro in the Pacific's Marshall Islands. Neither facility reported any direct telemetry contact with the spacecraft during the first half-hour after launch. However, a Doppler tracking signal did momentarily track the spacecraft at Petropavlovsk a little over ten minutes into the flight. The signal was then lost, possibly due to the planned burn of the orbital injection kick motor. "They have analyzed the Petropavlovsk data and all indications are that the spacecraft was running its program as expected, at least at the beginning of the Kamchatka contact," officials said. Project Director Louis Friedman -- watching the events unfold from mission control in Moscow -- said the Doppler data also indicated the kick motor did fire for the planned duration. But now that seems uncertain. Further analysis of the tracking information shows what appears to be acceleration as the engine burn begins, however, the signal gets "noisy" and difficult to understand. "Indications are that (the) orbit burn was received over Kamchatka. That data cuts off. This could be normal, related to the rocket firing; or it could indicate an anomaly. This is unknown," Friedman said. "It looks like it may be a long night here in Moscow and a long day in Pasadena." A later communications opportunity via permanent ground stations over 90 minutes after launch also turned up no news on the fate of Cosmos 1. The Tarusa UHF station and the Bear Lakes S-band antenna near Moscow, along with another pair of UHF and S-band antennas at Panska Ves in the Czech Republic, were to have had marginal views of the spacecraft at low elevations near the horizon. As the intermittent Volna rocket telemetry was further analyzed, officials noted potential problems during the launch phase. "There is some that doesn't appear quite right," said Emily Lakdawalla, Project Operations Assistant and Image Processing Coordinator for Cosmos 1. "At the same point, there is this apparent indication of an orbit insertion motor firing at about the right time. But nothing happened after that, except the data went noisy, and we don't know," she reported shortly after 2200 GMT (6:00 p.m. EDT). Attempts to track the spacecraft by the U.S. military also revealed no evidence of the craft in orbit. That indicated the solar sail was either shot into the wrong orbital perch or never achieved orbit at all. A shortened firing by the first stage would explain either scenarios. "Negative news is not good news," said Planetary Society Chairman Bruce Murray. "On the other hand, we do not have direct evidence for failure. This is not what we'd hoped to have happen." The next communications passes at Tarusa and Bear Lakes are slated for about 0423 GMT (12:23 a.m. EDT) Wednesday morning. But that timing assumes the spacecraft is flying in the intended orbit. The potential that Cosmos is even circling the planet tonight is questionable, based on a Russian news story that quotes the Northern Fleet as saying the first stage engine experienced "a spontaneous stoppage" 83 seconds into launch. The vehicle was allowed to continue flying because it lacked a destruct system. But there has been no further confirmation of the report. If the Volna did fail, it would be the second launch mishap of the day for the Russian space program. A military communications satellite crashed back to Earth this morning after its Molniya rocket failed to deliver the craft to orbit. See our separate story on that botched mission here. The three stages of the liquid-fueled Volna booster were to have completed their job just over six minutes after liftoff. The third stage was then to have jettisoned, followed by the release of the protective payload fairing that shielded the Cosmos 1 spacecraft during its launch through the lower atmosphere. Thrusters were then slated to fire to spin up the solar sail to about 22.5 revolutions per minute for stabilization prior to the orbital injection kick motor's ignition to inject Cosmos 1 into its 500-mile high orbit. That was expected to come at a point 15 minutes, 45 seconds into the flight, while cutoff was programmed to occur almost four minutes later. Plans then called for the spacecraft to spin down, followed by the separation of Cosmos 1 from its kick motor. Four electricity-producing solar panels were expected to deploy about 44 minutes after liftoff to relieve the strain on batteries that powered the craft during the initial portion of the flight. Solar sails could play a key role in future long-distance space missions because they are able to utilize the Sun's light pressure by essentially unfurling large lightweight structures that can reflect light. This lessens the need to carry large amounts of massive chemical rocket fuels for maneuvering thrusters. Developed and built by Russia's NPO Lavochkin firm at a factory outside Moscow, Cosmos 1 was largely funded by The Planetary Society members, private donors, and a science media venture known as Cosmos Studios. Cosmos 1 draws upon decades of research and testing of the solar sail concept, but this mission marks the first time such a craft has ever been sent into orbit to demonstrate the ability to use particles sunlight known as photons as a means of propulsion. Deployment tests on the ground and in space have been carried out over the past few years by space agencies around the world, but Cosmos 1 will be the first to fully incorporate a solar sail structure to attempt to demonstrate the feasibility of its use as a propulsion system. Ground controllers at the primary operations center in Russia will verify the performance of all aspects of the spacecraft before going ahead with the deployment of eight ultra-thin sail blades a few days after launch. Each blade is composed of a reinforced mylar material that measures just five microns thick, or about a quarter of the thickness of a normal household trash bag. They were compactly folded and housed inside containers for launch. From its perch some 500 miles high, Cosmos 1 is expected to be visible to skywatchers around the world after it unfurls its eight solar sail blades no earlier than Sunday in pairs of four at a time. Each blade is about 50 feet in length, and the entire structure will span about 100 feet tip-to-tip. The eight blades will cover a surface area of about 6,500 square feet. This is well over the size of a regulation basketball court. The Planetary Society is seeking input from amateur observers throughout the mission to help determine just how bright and reflective the sails are. It is believed Cosmos 1 will be one of the brightest satellites crossing the night sky. Enthusiasts can also submit photos of the craft passing high above for entry into a contest. More elaborate observations of Cosmos 1 will come from the United States Air Force Maui Optical and Supercomputing Site in Hawaii. High resolution cameras will attempt to gather detailed images of the spacecraft soon after the sails spring into action. Once the sails are stabilized after the deployment, officials will attempt to rotate the blades and use the sail to control the orientation of the spacecraft. The blades are mounted on a fixture that can be moved to shift the angle of the sail to the Sun. After several weeks, it is hoped that tracking data will reveal the affects of light pressure from the Sun propelling the sails into a higher orbit around Earth. Officials would consider such information as proof that the experiment was a success. Cameras aboard Cosmos 1 will also capture images to downlink to Earth from shortly after launch and through the deployment of the solar sail to get an up-close view of how the spacecraft is functioning. The 220-pound Cosmos 1 had to clear many hurdles before finally being shipped from its NPO Lavochkin factory to the Russian naval port at Severmorsk on the Barents Sea inside the Arctic Circle. A testbed of the craft launched aboard another Volna rocket in July 2001 on a suborbital test flight, but a separation mechanism failed. The demonstrator likely crashed in Russia's far east and was never recovered. Russian officials put the Volna system through an extended series of tests to determine and fix the problem that plagued not only the Cosmos 1 test flight, but also the mission of an inflatable heat shield demonstrator in 2002. The rocket was finally cleared in late 2003 allowing the final assembly of the spacecraft to be completed through the following year prior to the transfer of the satellite to Severmorsk last month. |
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