The Znamya project was a series of experimental orbital mirrors, designed to beam solar power

Solar power

Solar energy, radiant light and heat from the sun, has been harnessed by humans since ancient times using a range of ever-evolving technologies. Solar radiation, along with secondary solar-powered resources such as wind and wave power, hydroelectricity and biomass, account for most of the available...

 to Earth by reflecting sunlight

Sunlight

Sunlight, in the broad sense, is the total frequency spectrum of electromagnetic radiation given off by the Sun. On Earth, sunlight is filtered through the Earth's atmosphere, and solar radiation is obvious as daylight when the Sun is above the horizon.When the direct solar radiation is not blocked...

. It consisted of two experiments - the Znamya 2 experiment, and the failed Znamya 2.5 - and the proposed Znamya 3. The project was abandoned by the Russian Federal Space Agency

Russian Federal Space Agency

The Russian Federal Space Agency , commonly called Roscosmos and abbreviated as FKA and RKA , is the government agency responsible for the Russian space science program and general aerospace research. It was previously the Russian Aviation and Space Agency .Headquarters of Roscosmos are located...

 after the failed deployment of the Znamya 2.5.

Znamya 2

The Znamya 2 was a 20-metre wide space solar mirror

Solar mirror

A solar mirror is a reflective surface used for gathering and reflecting solar energy in a system being powered by solar energy. It comprises a substrate with a reflective layer for reflecting the solar energy, and in most cases an interference layer...

. Znamya-2 was launched aboard Progress M-15

Progress M-15

Progress M-15 was a Russian unmanned cargo spacecraft which was launched in 1992 to resupply the Mir space station. The thirty-third of sixty-four Progress spacecraft to visit Mir, it used the Progress-M 11F615A55 configuration, and had the serial number 215...

 from Baikonur

Baikonur Cosmodrome

The Baikonur Cosmodrome , also called Tyuratam, is the world's first and largest operational space launch facility. It is located in the desert steppe of Kazakhstan, about east of the Aral Sea, north of the Syr Darya river, near Tyuratam railway station, at 90 meters above sea level...

 on 27 October 1992. After visiting the EO-12 crew aboard the Mir

Mir

Mir was a space station operated in low Earth orbit from 1986 to 2001, at first by the Soviet Union and then by Russia. Assembled in orbit from 1986 to 1996, Mir was the first modular space station and had a greater mass than that of any previous spacecraft, holding the record for the...

 space station

Space station

A space station is a spacecraft capable of supporting a crew which is designed to remain in space for an extended period of time, and to which other spacecraft can dock. A space station is distinguished from other spacecraft used for human spaceflight by its lack of major propulsion or landing...

 the Progress T-15 then undocked and deployed the reflector from the end of the Russian progress spacecraft

Progress spacecraft

The Progress is a Russian expendable freighter spacecraft. The spacecraft is an unmanned resupply spacecraft during its flight but upon docking with a space station, it allows astronauts inside, hence it is classified manned by the manufacturer. It was derived from the Soyuz spacecraft, and is...

 on February 4, 1993, next to the Russian Mir

Mir

Mir was a space station operated in low Earth orbit from 1986 to 2001, at first by the Soviet Union and then by Russia. Assembled in orbit from 1986 to 1996, Mir was the first modular space station and had a greater mass than that of any previous spacecraft, holding the record for the...

 space station. The mirror deployed successfully, and, when illuminated, produced a 5 km wide bright spot, which traversed Europe from southern France

France

The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

 to western Russia

Russia

Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

 at a speed of 8 km/second.http://www.space-frontier.org/Events/Znamya/ The bright spot had a luminosity

Luminosity

Luminosity is a measurement of brightness.-In photometry and color imaging:In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre.The luminosity function...

 equivalent to approximately that of a full moon

Full moon

Full moon lunar phase that occurs when the Moon is on the opposite side of the Earth from the Sun. More precisely, a full moon occurs when the geocentric apparent longitudes of the Sun and Moon differ by 180 degrees; the Moon is then in opposition with the Sun.Lunar eclipses can only occur at...

.http://www.triz-journal.com/archives/2002/06/e/index.htm Although clouds covered much of Europe that morning, a few ground observers reported seeing a flash of light as the beam swept by.

The mirror was de-orbited after several hours, and burned up in atmospheric reentry

Atmospheric reentry

Atmospheric entry is the movement of human-made or natural objects as they enter the atmosphere of a celestial body from outer space—in the case of Earth from an altitude above the Kármán Line,...

 over Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

.

The Znamya mirror had originally been designed as a prototype of a solar sail

Solar sail

Solar sails are a form of spacecraft propulsion using the radiation pressure of light from a star or laser to push enormous ultra-thin mirrors to high speeds....

 propulsion system , but was repurposed as a space mirror for illumination when interest in solar sails flagged.

Znamya 2.5

The Znamya 2.5 was a successor to the Znamya 2, which was deployed on February 5, 1999. It had a diameter of 25 m, and was expected to produce a bright spot 7 km in diameter, with luminosity between five and ten full moons. However, soon after deployment, the mirror caught on an antenna on Mir

Mir

Mir was a space station operated in low Earth orbit from 1986 to 2001, at first by the Soviet Union and then by Russia. Assembled in orbit from 1986 to 1996, Mir was the first modular space station and had a greater mass than that of any previous spacecraft, holding the record for the...

, and ripped. After several vain attempts by Russian mission control

Mission Control Center

A mission control center is an entity that manages aerospace vehicle flights, usually from the point of lift-off until the landing or the end of the mission. A staff of flight controllers and other support personnel monitor all aspects of the mission using telemetry, and send commands to the...

 to free the mirror from the antenna, the Znamya 2.5 was de-orbited, and burned up upon reentry

Atmospheric reentry

Atmospheric entry is the movement of human-made or natural objects as they enter the atmosphere of a celestial body from outer space—in the case of Earth from an altitude above the Kármán Line,...

.http://news.bbc.co.uk/2/hi/science/nature/273220.stm, http://www.triz-journal.com/archives/2002/06/e/index.htm.

Znamya 3

The Znamya 3 was intended to be a scaled-up version of the previous two Znamyas, with a diameter of 60-70 metres. It was never built, as the project was abandoned after the failure of the Znamya 2.5. http://www.space-frontier.org/Events/Znamya/

External links

• "Space Mirror, N.Shpakovsky.