This article possibly contains original research .(February 2019) |
In speculative fiction, a force field, sometimes known as an energy shield, force shield, energy bubble, or deflector shield, is a barrier produced by something like energy, negative energy, dark energy, electromagnetic fields, gravitational fields, electric fields, quantum fields, telekinetic fields, plasma, particles, radiation, solid light, magic, or pure force. It protects a person, area, or object from attacks or intrusions, or even deflects energy attacks back at the attacker. This fictional technology is created as a field of energy without matter that acts as a wall, so that objects affected by the particular force relating to the field are unable to pass through the field and reach the other side, instead being deflected or destroyed. Actual research in the 21st century has looked into the potential to deflect radiation or cosmic rays, as well as more extensive shielding.
This concept has become a staple of many science-fiction works, so much so that authors frequently do not even bother to explain or justify them to their readers, treating them almost as established fact and attributing whatever capabilities the plot requires. The ability to create force fields has become a frequent superpower in superhero media.
The concept of a force field goes back at least as far as early 20th century. The Encyclopedia of Science Fiction suggests that the first use of the term in science fiction was in 1931, in Spacehounds of IPC by E.E. 'Doc' Smith. [1]
An early precursor of what is now called "force field" may be found in William Hope Hodgson's The Night Land (1912), where the Last Redoubt, the fortress of the remnants of a far-future humanity, is kept safe by "The Air Clog" generated by the burning "Earth-Current". [2] [1] An even earlier precursor is Florence Carpenter Dieudonné's 1887 novel Rondah, or Thirty-Three Years in a Star, [1] where the far-off Sun Island is enclosed by a "wall in the air" that blocks access by land, sea and air, which is occasionally disabled. [3]
In Isaac Asimov's Foundation universe, personal shields have been developed by scientists specializing in the miniaturization of planet-based shields. As they are primarily used by Foundation Traders, most other inhabitants of the Galactic Empire do not know about this technology. In an unrelated short story Breeds There a Man...? by Asimov, scientists are working on a force field ("energy so channelled as to create a wall of matter-less inertia"), capable of protecting the population in case of a nuclear war. The force field demonstrated in the end is a solid hemisphere, apparently completely opaque and reflective from both sides. Asimov explores the force field concept again in the short story Not Final!.
The concept of force fields as a defensive measure from enemy attack or as a form of attack can be regularly found in modern video games as well as in film, such as in The War of the Worlds (1953, George Pál) and Independence Day .
The ability to create a force field has been a common superpower in comic books and associated media. While only a few characters have the explicit ability to create force fields (for example, the Invisible Woman of the Fantastic Four and Violet Parr from The Incredibles ), it has been emulated via other powers, such as Green Lantern's energy constructs, Jean Grey's telekinesis, and Magneto's manipulation of electromagnetic fields. Apart from this, its importance is also highlighted in Dr. Michio Kaku's books (such as Physics of the Impossible ).
Science fiction and fantasy avenues suggest a number of potential uses of force fields: [4]
The capabilities and functionality of force fields vary; in some works of fiction (such as in the Star Trek universe), energy shields can nullify or mitigate the effects of both energy and particle (e.g., phasers) and conventional weapons, as well as supernatural forces. In many fictional scenarios, the shields function primarily as a defensive measure against weapons fired from other spacecraft. Force fields in these stories also generally prevent transporting. There are generally two kinds of force fields postulated: one in which energy is projected as a flat plane from emitters around the edges of a spacecraft and another where energy surrounds a ship like a bubble.
The ability to create force fields has become a frequent superpower in superhero media. While sometimes an explicit power on their own, force fields have also been attributed to other fictional abilities. Marvel Comics' Jean Grey is able to use her telekinesis to create a barrier of telekinetic energy that acts as a force field by repelling objects. Similarly, Magneto is able to use his magnetism to manipulate magnetic fields into acting as shields. The most common superpower link seen with force fields is the power of invisibility. This is seen with Marvel Comics' Invisible Woman and Disney Pixar's Violet Parr.
Force fields often vary in what they are made of, though are commonly made of energy. The 2017 series The Gifted featured character Lauren Strucker who had the ability to create shields by pushing molecules together. This resulted in her being able to construct force fields out of air and water particles rather than energy.
In 2005, the NASA Institute for Advanced Concepts devised a way to protect from radiation by applying an electric field to spheres made of a thin, non-conductive material coated with a layer of gold with either positive or negative charges, which could be arranged to bend a stream of charged particles to protect from radiation. [5]
In 2006, a University of Washington group in Seattle had been experimenting with using a bubble of charged plasma, contained by a fine mesh of superconducting wire, to surround a spacecraft. [6] This would protect the spacecraft from interstellar radiation and some particles without needing physical shielding.
The Rutherford Appleton Laboratory was in 2007 attempting to design an actual test satellite, which would orbit Earth with a charged plasma field around it. [7] [8] [9] [10]
In 2008, Cosmos Magazine reported on research into creating an artificial replica of Earth's magnetic field around a spacecraft to protect astronauts from dangerous cosmic rays. [11] British and Portuguese scientists used a mathematical simulation to prove that it would be possible to create a "mini-magnetosphere" bubble several hundred meters across, possibly generated by a small uncrewed vessel that could accompany a future crewed mission to Mars.
In 2014, a group of students from the University of Leicester released a study describing functioning of spaceship plasma deflector shields. [12]
In 2015, Boeing was granted a patent on a force field system designed to protect against shock waves generated by explosions. It is not intended to protect against projectiles, radiation, or energy weapons such as lasers. The field purportedly works by using a combination of lasers, electricity and microwaves to rapidly heat up the air creating a field of (ionised) superheated air-plasma which disrupts, or at least attenuates, the shock wave. As of March 2016, no working models were known to have been demonstrated. [13] [14]
In 2016, Rice University scientists discovered that Tesla coils can generate force fields able to manipulate matter (process called teslaphoresis). [15] [16] [17]
Spacecraft propulsion is any method used to accelerate spacecraft and artificial satellites. In-space propulsion exclusively deals with propulsion systems used in the vacuum of space and should not be confused with space launch or atmospheric entry.
The solar wind is a stream of charged particles released from the Sun's outermost atmospheric layer, the corona. This plasma mostly consists of electrons, protons and alpha particles with kinetic energy between 0.5 and 10 keV. The composition of the solar wind plasma also includes a mixture of particle species found in the solar plasma: trace amounts of heavy ions and atomic nuclei of elements such as carbon, nitrogen, oxygen, neon, magnesium, silicon, sulfur, and iron. There are also rarer traces of some other nuclei and isotopes such as phosphorus, titanium, chromium, and nickel's isotopes 58Ni, 60Ni, and 62Ni. Superimposed with the solar-wind plasma is the interplanetary magnetic field. The solar wind varies in density, temperature and speed over time and over solar latitude and longitude. Its particles can escape the Sun's gravity because of their high energy resulting from the high temperature of the corona, which in turn is a result of the coronal magnetic field. The boundary separating the corona from the solar wind is called the Alfvén surface.
An ion thruster, ion drive, or ion engine is a form of electric propulsion used for spacecraft propulsion. An ion thruster creates a cloud of positive ions from a neutral gas by ionizing it to extract some electrons from its atoms. The ions are then accelerated using electricity to create thrust. Ion thrusters are categorized as either electrostatic or electromagnetic.
A fusion rocket is a theoretical design for a rocket driven by fusion propulsion that could provide efficient and sustained acceleration in space without the need to carry a large fuel supply. The design requires fusion power technology beyond current capabilities, and much larger and more complex rockets.
An antimatter rocket is a proposed class of rockets that use antimatter as their power source. There are several designs that attempt to accomplish this goal. The advantage to this class of rocket is that a large fraction of the rest mass of a matter/antimatter mixture may be converted to energy, allowing antimatter rockets to have a far higher energy density and specific impulse than any other proposed class of rocket.
A tractor beam is a device that can attract one object to another from a distance. The concept originates in fiction: The term was coined by E. E. Smith in his novel Spacehounds of IPC (1931). Since the 1990s, technology and research have labored to make it a reality, and have had some success on a microscopic level. Less commonly, a similar beam that repels is known as a pressor beam or repulsor beam. Gravity impulse and gravity propulsion beams are traditionally areas of research from fringe physics that coincide with the concepts of tractor and repulsor beams.
Van Allen radiation belt is a zone of energetic charged particles, most of which originate from the solar wind, that are captured by and held around a planet by that planet's magnetosphere. Earth has two such belts, and sometimes others may be temporarily created. The belts are named after James Van Allen, who is often credited with their discovery.
Nuclear pulse propulsion or external pulsed plasma propulsion is a hypothetical method of spacecraft propulsion that uses nuclear explosions for thrust. It originated as Project Orion with support from DARPA, after a suggestion by Stanislaw Ulam in 1947. Newer designs using inertial confinement fusion have been the baseline for most later designs, including Project Daedalus and Project Longshot.
Space weather is a branch of space physics and aeronomy, or heliophysics, concerned with the varying conditions within the Solar System and its heliosphere. This includes the effects of the solar wind, especially on the Earth's magnetosphere, ionosphere, thermosphere, and exosphere. Though physically distinct, space weather is analogous to the terrestrial weather of Earth's atmosphere. The term "space weather" was first used in the 1950s and popularized in the 1990s. Later, it prompted research into "space climate", the large-scale and long-term patterns of space weather.
The plasma window is a technology that fills a volume of space with plasma confined by a magnetic field. With current technology, this volume is quite small and the plasma is generated as a flat plane inside a cylindrical space.
Space environment is a branch of astronautics, aerospace engineering and space physics that seeks to understand and address conditions existing in space that affect the design and operation of spacecraft. A related subject, space weather, deals with dynamic processes in the solar-terrestrial system that can give rise to effects on spacecraft, but that can also affect the atmosphere, ionosphere and geomagnetic field, giving rise to several other kinds of effects on human technologies.
A particle-beam weapon uses a high-energy beam of atomic or subatomic particles to damage the target by disrupting its atomic and/or molecular structure. A particle-beam weapon is a type of space-based directed-energy weapon, which directs focused energy toward a target using atomic scale particles. Some particle-beam weapons have potential practical applications, e.g. as an antiballistic missile defense or detection system. They have been known by several names: particle accelerator guns, ion cannons, proton beams, lightning rays, rayguns, etc.
The plasmasphere, or inner magnetosphere, is a region of the Earth's magnetosphere consisting of low-energy (cool) plasma. It is located above the ionosphere. The outer boundary of the plasmasphere is known as the plasmapause, which is defined by an order of magnitude drop in plasma density. In 1963 American scientist Don Carpenter and Soviet astronomer Konstantin Gringauz proved the plasmasphere and plasmapause's existence from the analysis of very low frequency (VLF) whistler wave data. Traditionally, the plasmasphere has been regarded as a well behaved cold plasma with particle motion dominated entirely by the geomagnetic field and, hence, co-rotating with the Earth.
A plasma propulsion engine is a type of electric propulsion that generates thrust from a quasi-neutral plasma. This is in contrast with ion thruster engines, which generate thrust through extracting an ion current from the plasma source, which is then accelerated to high velocities using grids/anodes. These exist in many forms. However, in the scientific literature, the term "plasma thruster" sometimes encompasses thrusters usually designated as "ion engines".
Heliophysics is the physics of the Sun and its connection with the Solar System. NASA defines heliophysics as "(1) the comprehensive new term for the science of the Sun - Solar System Connection, (2) the exploration, discovery, and understanding of Earth's space environment, and (3) the system science that unites all of the linked phenomena in the region of the cosmos influenced by a star like our Sun."
The Van Allen Probes, formerly known as the Radiation Belt Storm Probes (RBSP), were two robotic spacecraft that were used to study the Van Allen radiation belts that surround Earth. NASA conducted the Van Allen Probes mission as part of the Living With a Star program. Understanding the radiation belt environment and its variability has practical applications in the areas of spacecraft operations, spacecraft system design, mission planning and astronaut safety. The probes were launched on 30 August 2012 and operated for seven years. Both spacecraft were deactivated in 2019 when they ran out of fuel. They are expected to deorbit during the 2030s.
Astronautical hygiene evaluates, and mitigates, hazards and health risks to those working in low-gravity environments. The discipline of astronautical hygiene includes such topics as the use and maintenance of life support systems, the risks of the extravehicular activity, the risks of exposure to chemicals or radiation, the characterization of hazards, human factor issues, and the development of risk management strategies. Astronautical hygiene works side by side with space medicine to ensure that astronauts are healthy and safe when working in space.
Health threats from cosmic rays are the dangers posed by cosmic rays to astronauts on interplanetary missions or any missions that venture through the Van-Allen Belts or outside the Earth's magnetosphere. They are one of the greatest barriers standing in the way of plans for interplanetary travel by crewed spacecraft, but space radiation health risks also occur for missions in low Earth orbit such as the International Space Station (ISS).
Energetic Neutral Atom (ENA) imaging is a technology used to create global images of otherwise invisible phenomena in the magnetospheres of planets and throughout the heliosphere.
The space-opera blockbuster, Star Wars franchise has borrowed many real-life scientific and technological concepts in its settings. In turn, Star Wars has depicted, inspired, and influenced several futuristic technologies, some of which are in existence and others under development. In the introduction of the Return of the Jedi novelization, George Lucas wrote: "Star Wars is also very much concerned with the tension between humanity and technology, an issue which, for me, dates back even to my first films. In Jedi, the theme remains the same, as the simplest of natural forces brought down the seemingly invincible weapons of the evil Empire."