Cosmos 1

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This article is about the solar sail. For Cosmos 1 from the Cosmos series, see Sputnik 11.

An artist's rendering of Cosmos 1 orbiting the Earth.

Cosmos 1 was a project by The Planetary Society to test a solar sail in space. As part of the project, an unmanned solar sail spacecraft was launched into space at 15:46:09 EDT (19:46:09 UTC) on June 21, 2005, from the submarine Borisoglebsk in the Barents Sea. However, a rocket failure prevented it from reaching its intended orbit. Once in orbit, the spacecraft was supposed to deploy a large sail, upon which photons from the Sun would push, thereby increasing the spacecraft's velocity (the contributions from the solar wind are similar, but of much smaller magnitude).

Had the mission been successful, it would have been the first-ever orbital use of a solar sail to speed up a spacecraft, as well as the first space mission by a space advocacy group. The project budget was USD $4 million.

1 Current status
2 Planned mission profile
- 2.1 Possible beam propulsion
- 2.2 Tracking
3 Physics
4 Other aspects
5 Latest news
6 References
7 External links

[edit] Current status

2005-June 21 15:46:09 EDT (19:46:09 UTC) The Cosmos 1 sail was launched.

Initially, the first few ground stations did not report a signal from the spacecraft, raising fears that the spacecraft was lost on launch.

2005-June-21 14:00 PDT (21:00 UTC), the Russian news agency Interfax reported that the spacecraft failed to reach orbit at the expected time.

2005-June-21 15:13 PDT (22:13 UTC), the Russian news agency ITAR-TASS reported "the engine of the first stage of a Volna booster spontaneously stopped working at the 83rd second of the flight" (Report), (in Russian)

2005-June 22 21:40 PDT (04:40 UTC), the Planetary Society announced, "We have found what we believe are spacecraft signals in the data recorded at [several] tracking stations...If confirmed, these data will indicate that Cosmos 1 made it to orbit, albeit possibly an incorrect orbit. (Press release)

2005-June-22 10:30 PDT (17:30 UTC), the Planetary Society issued a statement that "the Russian space agency (RKA) has made a tentative conclusion that the Volna rocket carrying Cosmos 1 failed during the firing of the first stage. This would mean that Cosmos 1 is lost," but data "might indicate that Cosmos 1 made it into orbit, but probably a lower one than intended. The project team now considers this to be a very small probability."

2005-June 23 17:10 PDT (10:10 GMT), the Russian space agency said the Volna rocket booster carrying the spacecraft had failed 83 seconds after launch due to a problem with the first stage engine of the three-stage booster. "The booster's failure means that the solar sail vehicle was lost," said agency spokesperson Vyacheslav Davidenko. "The Russian navy is searching the area for the debris of the booster and the vehicle."^[1]

2005-July 20, the Planetary Society issued a statement that The Volna Failure Review Board convened by the Makeev Rocket Design Bureau, manufacturers of the Volna launch vehicle, has made its final report to the Russian space agency, Roskosmos, concerning the attempted June 21 launch of the Cosmos 1 spacecraft. They concluded that the telemetry data from the launch vehicle was sufficient to determine that the launch failed due to a premature shut-down of the first-stage engine (82.86 s of expected ~100 seconds burn) caused by a “critical degradation in operational capability of the engine turbo-pump.”. The Planetary Society was not invited to be part of the failure review and they received a warning from the U.S. State Department reminding that, under International Arms Traffic Regulations (ITAR), they were not allowed to participate in a launch failure review without U.S.S.D. approval. But even before the failure review, there was a serious lack of communication and coordination with the project and launch vehicle teams.^[2]

2005-September 30, the Planetary Society stated that Cosmos 1 did not reach orbit, because the Volna rocket selected had not been upgraded to correct a known failure mode. Telemetry data showed that the assembly vibrated abnormally at a frequency consistent with its rotor failing. The Planetary Society is now ready to find a new launch vehicle, establish better launch vehicle interfaces, and try again to fly the first solar sail spacecraft.^[3]

[edit] Planned mission profile

To test the solar sail concept, the Cosmos 1 project launched an orbital spacecraft with a full complement of eight sail blades on June 21, 2005 — the summer solstice. The spacecraft had a mass of 100 kg (220 lb) and consisted of eight triangular sail blades which would be deployed from a central hub after launch by the inflating of structural tubes. The sail blades were each 15 m long, had a total surface area of 600 square meters, and were made of aluminized reinforced PET film.

The spacecraft was launched on a Volna rocket (a converted SS-N-18 ICBM) from a Russian Delta III submarine, the Borisoglebsk, submerged in the Barents Sea. The spacecraft's initial circular orbit would have been at an altitude of about 800 km, where it would have unfurled the sails. The sails would then have gradually raised the spacecraft to a higher earth orbit. "Cosmos 1 might boost its orbit 31 to 62 miles [50 to 100 km] over the expected 30-day life of the mission," said Louis Friedman of the Planetary Society.^[4]^[5]

The mission was expected to end within a month of launch as the Mylar of the blades would degrade in sunlight.

[edit] Possible beam propulsion

The solar sail craft could also have been used to measure the effect of artificial microwaves aimed at it from a radar installation. A 70 m dish at the Goldstone facility of NASA's Deep Space Network would have been used to irradiate the sail with a 450 kW beam. This experiment in beam-powered propulsion would only have been attempted after the prime mission objective of controlled solar sail flight was achieved.

[edit] Tracking

The craft would have been visible to the naked eye from most of the Earth's surface: the planned orbit had an inclination of 80°, so it would have been visible from latitudes of up to approximately 80° north and south.

A network of tracking stations around the world tried to maintain contact with the solar sail during the mission. Tracking stations included the Tarusa station, 75 miles (120 km) south of Moscow, and the Space Sciences Laboratory at the University of California-Berkeley. Mission control was based primarily at the Russian company NPO Lavochkin in Moscow — a centre that the Planetary Society calls Mission Operations Moscow (MOM).

[edit] Physics

The craft would have been gradually accelerating during each orbit as a result of the radiation pressure of photons colliding with the sails. As photons reflect off the surface of the sails, they transfer momentum to the object. As there would be no air resistance to oppose the velocity of the spacecraft, acceleration is proportional to the number of photons colliding with it per unit time. Sunlight amounts to a tiny 5×10^-4 m/s² acceleration in the vicinity of the Earth. Over one day, its speed would reach 45 m/s (100mph); in 100 days its speed would be 4,500 m/s (10,000 mph), in 2.74 years 45,000 m/s (100,000 mph).

At that speed, a craft would reach Pluto, a very distant dwarf planet in the Solar System, in less than five years.^[6] Even this tiny acceleration is larger than that of some other propulsion techniques; for example, the ion thruster-propelled SMART-1 spacecraft has a maximum acceleration of 2×10^-4 m/s², allowing SMART-1 to achieve lunar orbit in 2004-November.

[edit] Other aspects

Besides the main spacecraft, launched in June 2005, the Cosmos 1 project has funded two other craft:

A suborbital test was attempted in 2001 with only two sail blades. The spacecraft failed to separate from the rocket.
A second orbital spacecraft is under construction, but the launch date (if any) has not been set.

One of Cosmos 1's solar sail blades was displayed at the Rockefeller Center office complex in New York City in 2003.

[edit] Latest news

Planetary Society's solar sail updates and press releases - current information about the Cosmos 1 project.
Planetary Society's Cosmos 1 weblog, updated daily until launch, and then as events warrant.