A laser broom is a proposed ground-based

laser A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of radi ...

beam-powered propulsion Beam-powered propulsion, also known as directed energy propulsion, is a class of aircraft or spacecraft propulsion that uses energy beamed to the spacecraft from a remote power plant to provide energy. The beam is typically either a microwave or a ...

system that sweeps

space debris Space debris (also known as space junk, space pollution, space waste, space trash, space garbage, or cosmic debris) are defunct human-made objects in spaceprincipally in Earth orbitwhich no longer serve a useful function. These include dere ...

out of the path of

artificial satellites A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation (GPS), broadcasting, scientifi ...

(such as the

International Space Station The International Space Station (ISS) is a large space station that was Assembly of the International Space Station, assembled and is maintained in low Earth orbit by a collaboration of five space agencies and their contractors: NASA (United ...

) to prevent collateral damage to space equipment. It heats up one side of the debris to shift its orbit trajectory, altering the path to hit the atmosphere sooner. Space researchers have proposed that a laser broom may help mitigate

Kessler syndrome The Kessler syndrome, also known as the Kessler effect, collisional cascading, or ablation cascade, is a scenario proposed by NASA scientists Donald J. Kessler and Burton G. Cour-Palais in 1978. It describes a situation in which the density of o ...

, a runaway cascade of collision events between orbiting objects. Additionally, laser broom systems mounted on satellites or space station have also been proposed.

Mechanism

Laser brooms are proposed to target space debris between in diameter. Collisions with these high-velocity debris not only cause considerable damage to the satellites but secondary fragmented debris from the collided satellite parts. A laser broom is intended to be used at a high power to penetrate through the atmosphere and

ablate Ablation ( – removal) is the removal or destruction of something from an object by vaporization, chipping, erosive processes, or by other means. Examples of ablative materials are described below, including spacecraft material for ascent and ...

material from the targeted debris. The ablating material imparts a small

thrust Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that ...

that lowers its orbital

perigee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides perta ...

towards the upper atmosphere, thereby increasing drag so that its remaining orbital life is cut short.Ivan Bekey,
Project Orion: Orbital Debris Removal Using Ground-Based Sensors and Lasers
.", ''Second European Conference on Space Debris'', 1997, ESA-SP 393, p. 699. The laser would operate in a pulsed fashion to avoid the target from self-shielding via its ablated plasma. The power levels of lasers in this concept are well below the power levels in concepts for more rapidly effective anti-satellite weapons. Research into this field reveal the precise physical constraints required, noting the significant relevance to the space debris's orientation and resultant trajectory of the ablated object. Using a laser guide star and adaptive optics, a sufficiently large ground-based laser (1 megajoule pulsed HF laser) can offset the orbits of dozens of debris daily at a reasonable cost.

History

The

Space Shuttle The Space Shuttle is a retired, partially reusable launch system, reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. ...

routinely showed evidence of "tiny" impacts upon post-flight inspection. ''Orion'' was a proposed ground-based laser broom project in the 1990s, estimated to cost $500 million. A space-based laser also called "Project Orion" was planned to be installed on the

in 2003. In 2015, Japanese researchers proposed adding laser broom capabilities to the Extreme Universe Space Observatory telescope, to be launched to the ISS in 2017. In 2014, the European CLEANSPACE project published a report studying a global architecture of debris tracking and removal laser stations.

References

External links

BBC News report on Laser broom

ABC

Agence France-Presse Agence France-Presse (; AFP) is a French international news agency headquartered in Paris, France. Founded in 1835 as Havas, it is the world's oldest news agency. With 2,400 employees of 100 nationalities, AFP has an editorial presence in 260 c ...

story via SpaceDaily
Orbiting Junk Continues to Threaten International Space Station
Space.com
Shuttle to test space junk broom
New Scientist

by Claude Phipps
Wired October 2011: Space Junk Crisis: Time to Bring in the Lasers
story on Wired
Removing Orbital Debris with Pulsed Lasers
Broom, laser Spacecraft propulsion Space debris

Mechanism

History

References

Further reading

External links