A solar flare is a sudden brightening observed over the Sun surface or the solar limb, which is interpreted as a large energy release of up to 6 × 10²⁵ joules of energy (about a sixth of the total energy output of the Sun each second). The flare ejects clouds of electrons, ions, and atoms through the corona into space. These clouds typically reach the earth a day or two after the event. The term is also used to refer to similar phenomena in other stars, where the term stellar flare applies.

Solar flares affect all layers of the solar atmosphere (photosphere, chromosphere, and corona), when the medium plasma is heated to tens of millions of kelvins and electrons, protons, and heavier ions are accelerated to near the speed of light. They produce radiation across the electromagnetic spectrum at all wavelengths, from radio waves to gamma rays, although most of the energy goes to frequencies outside the visual range and for this reason the majority of the flares are not visible to the naked eye and must be observed with special instruments. Flares occur in active regions around sunspots, where intense magnetic fields penetrate the photosphere to link the corona to the solar interior. Flares are powered by the sudden (timescales of minutes to tens of minutes) release of magnetic energy stored in the corona. The same energy releases may produce coronal mass ejections (CME), although the relation between CMEs and flares is still not well established.

X-rays and UV radiation emitted by solar flares can affect Earth's ionosphere and disrupt long-range radio communications. Direct radio emission at decimetric wavelengths may disturb operation of radars and other devices operating at these frequencies.

Solar flares were first observed on the Sun by Richard Christopher Carrington and independently by Richard Hodgson in 1859 as localized visible brightenings of small areas within a sunspot group. Stellar flares have also been observed on a variety of other stars.

The frequency of occurrence of solar flares varies, from several per day when the Sun is particularly "active" to less than one every week when the Sun is "quiet", following the 11-year cycle (the solar cycle). Large flares are less frequent than smaller ones.

Cause

Flares occur when accelerated charged particles, mainly electrons, interact with the plasma medium. Scientific research has shown that the phenomenon of magnetic reconnection is responsible for the acceleration of the charged particles. On the Sun, magnetic reconnection may happen on solar arcades – a series of closely occurring loops of magnetic lines of force. These lines of force quickly reconnect into a low arcade of loops leaving a helix of magnetic field unconnected to the rest of the arcade. The sudden release of energy in this reconnection is in the origin of the particle acceleration. The unconnected magnetic helical field and the material that it contains may violently expand outwards forming a coronal mass ejection. This also explains why solar flares typically erupt from what are known as the active regions on the Sun where magnetic fields are much stronger on an average.

Although there is a general agreement on the flares' causes, the details are still not well known. It is not clear how the magnetic energy is transformed into the particle kinetic energy, nor it is known how the particles are accelerated to energies as high as 10 MeV (Mega Electronvolt) and beyond. There are also some inconsistencies regarding the total number of accelerated particles, which sometimes seems to be greater than the total number in the coronal loop. And we are far from being able to forecast flares.

Classification

Solar flares are classified as A, B, C, M or X according to the peak flux (in watts per square meter, W/m²) of 100 to 800 picometer X-rays near Earth, as measured on the GOES spacecraft. Each class has a peak flux ten times greater than the preceding one, with X class flares having a peak flux of order 10⁻⁴ W/m². Within a class there is a linear scale from 1 to 9, so an X2 flare is twice as powerful as an X1 flare, and is four times more powerful than an M5 flare. The more powerful M and X class flares are often associated with a variety of effects on the near-Earth space environment. This extended logarithmic classification is necessary because the total energies of flares range over many orders of magnitude, following a uniform distribution with flare frequency roughly proportional to the inverse of the total energy. Stellar flares and earthquakes show similar power-law distributions.

Another flare classification is based on Hα spectral observations. The scheme uses both the intensity and emitting surface. The classification in intensity is qualitative, referring the flares as: (f)aint, (n)ormal or (b)rilliant. The emitting surface is measured in terms of ''millionths'' of the hemisphere and is described below (The total hemisphere area ''A_H''=6.2 10¹² km².)

Classification !! Corrected Area
! !! [millionths of hemisphere]
S	< 100
1	100 - 250
2	250 - 600
3	600 - 1200
4	> 1200

A flare then is classified taking S or a number that represents its size and a letter that represents its peak intensity, v.g.: Sn is a ''normal subflare''.

Hazards

Solar flares strongly influence the local space weather in the vicinity of the Earth. They can produce streams of highly energetic particles in the solar wind, known as a solar proton event, or "coronal mass ejection" (CME). These particles can impact the Earth's magnetosphere (see main article at geomagnetic storm), and present radiation hazards to spacecraft, astronauts and cosmonauts.

A massive solar flare could knock out electric power for months.

The soft X-ray flux of X class flares increases the ionization of the upper atmosphere, which can interfere with short-wave radio communication and can heat the outer atmosphere and thus increase the drag on low orbiting satellites, leading to orbital decay. Energetic particles in the magnetosphere contribute to the aurora borealis and aurora australis. Energy in the form of hard x-rays can be damaging to spacecraft electronics and are generally the result of large plasma ejection in the upper chromosphere.

The radiation risks posed by coronal mass ejections are a major concern in discussions of a manned mission to Mars, the moon, or other planets. Energetic protons can pass through the human body, causing biochemical damage, and hence present a hazard to astronauts during interplanetary travel. Some kind of physical or magnetic shielding would be required to protect the astronauts. Most proton storms take two or more hours from the time of visual detection to reach Earth's orbit. A solar flare on January 20, 2005 released the highest concentration of protons ever directly measured, taking only 15 minutes after observation to reach Earth, indicating a velocity of approximately one-third light speed, giving astronauts as little as 15 minutes to reach shelter.

Observations

Flares produce radiation across the Electromagnetic spectrum, although with different intensity. They are not very intense at ''white light'', but they can be very bright at particular atomic lines. They normally produce bremsstrahlung in X-Rays and synchrotron radiation in radio.

History

Optical Observations. Richard Carrington observed for the first time a flare on 1 September 1859 projecting the image produced by an optical telescope, without filters. It was an extraordinarily intense ''white light flare''. Since flares produce copious amounts of radiation at Hα, adding a narrow ( ≈1 Å) passband filter centered at this wavelength to the optical telescope, allows the observation of not very bright flares with small telescopes. For years Hα was the main, if not the only, source of information about solar flares. Other passband filters are also used.

Radio Observations. During World War II, on 25 and 26 February 1942, British radar operators observed radiation that Stanley Hey interpreted as solar emission. Their discovery did not go to public until the end of the conflict. The same year Southword also observed the Sun in radio, but as with Hey, his observations were only known after 1945. In 1943 Grote Reber was the first to report radioastronomical observations of the Sun at 160 MHz. The fast development of Radioastronomy revealed new peculiarities of the solar activity like ''storms'' and ''bursts'' related with the flares. Today ground based radiotelescopes observe the Sun from ~100 MHz up to 400 GHz.

Space Telescopes. Since the beginning of the Space exploration, satellites bring to space telescopes that work at wavelengths below the UV, which are completely absorbed by the Atmosphere, and where flares may be very bright. Since the 1970s, the GOES series of satellites observe the Sun at ''Soft'' X-Rays, and their observations became the ''standard measure'' of flares, relegating in some sense, the Hα classification. ''Hard'' X-Rays were observed by many different instruments, being today the most important the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). Nonetheless, UV observations are today the ''stars'' of the solar imaging with their incredible fine details that reveal the complexity of the Solar Corona. Spacecraft may bring also radio detectors at very very long wavelengths (as long as a few km) that cannot propagate through the Ionosphere.

Optical telescopes

Big Bear Solar Observatory - Located in Big Bear Lake, California (USA) and operated by the New Jersey Institute of Technology is a solar dedicated observatory with different instruments, and has a huge data bank of full disk Hα images.

Swedish 1-m Solar Telescope Operated by the Institute for Solar Physics (Sweden), is located in the Observatorio del Roque de los Muchachos on the island of La Palma (Spain).

Radio telescopes

Nançay Radioheliographe is an interferometer composed of 48 antennas observing at meter-decimeter wavelengths. The radioheliographe is installed at the Nançay Radio Observatory (France).

Owens Valley Solar Array is a radio interferometer operated by New Jersey Institute of Technology consisting of 7 antenas observing from 1 to 18 GHz in both left and right circular polarization. OVSA is located in Owens Valley, California, (USA), now is under reform, increasing to 15 the total number of antennas and upgrading its control system.

Nobeyama Radioheliograph is an interferometer installed at the Nobeyama Radio Observatory (Japan) formed by 84 small (80 cm) antennas, with receivers at 17 GHz (left and right polarization) and 34 GHz operating simultaneously. It observes continuously the Sun, producing daily snapshots. (See link)

Nobeyama Radio Polarimeters are a set of radio telescopes installed at the Nobeyama Radio Observatory that observes continuously the full Sun (no images) at the frequencies of 1, 2, 3.75, 9.4, 17, 35, and 80 GHz, at left and right circular polarization.

Solar Submillimeter Telescope is a single dish telescope, that observes continuously the Sun at 212 and 405 GHz. It is installed at Complejo Astronomico El Leoncito in Argentina. It has a focal array composed by 4 beams at 212 GHz and 2 at 405 GHz, therefore it can locate instantaneously the position of the emitting source. SST is the only solar submillimeter telescope currently in operation.

Space telescopes

The following spacecraft missions have flares as their main observation target.

Yohkoh - The Yohkoh (originally Solar A) spacecraft observed the Sun with a variety of instruments from its launch in 1991 until its failure in 2001. The observations spanned a period from one solar maximum to the next. Two instruments of particular use for flare observations were the Soft X-ray Telescope (SXT), a glancing incidence low energy X-ray telescope for photon energies of order 1 keV, and the Hard X-ray Telescope (HXT), a collimation counting instrument which produced images in higher energy X-rays (15-92 keV) by image synthesis.

Wind -The Wind spacecraft is devoted to the study of the interplanetary medium. Since the Solar Wind is its main driver, solar flares effects can be traced with the instruments aboard Wind. Some of the WIND experiments are: a very low frequency spectrometer, (WAVES), particles detectors (EPACT, SWE) and a magnetometer (MFI).

GOES - The GOES spacecraft are satellites in geostationary orbits around the Earth that have measured the soft X-ray flux from the Sun since the mid 1970s, following the use of similar instruments on the SOLRAD satellites. GOES X-ray observations are commonly used to classify flares, with A, B, C, M, and X representing different powers of ten — an X-class flare has a peak 1-8 Å flux above 0.0001 W/m².

RHESSI - The Reuven Ramaty High Energy Solar Spectral Imager is designed to image solar flares in energetic photons from soft X rays (~3 keV) to gamma rays (up to ~20 MeV) and to provide high resolution spectroscopy up to gamma-ray energies of ~20 MeV. Furthermore, it has the capability to perform spatially resolved spectroscopy with high spectral resolution.

SoHO - The Solar and Heliospheric Observatory is collaboration between the ESA and NASA which is in operation since December, 1995. It carries 12 different instruments, among them the Extreme Ultraviolet Imaging Telescope (EIT), the Large Angle and Spectrometric Coronagraph (LASCO) and the Michelson Doppler Imager (MDI).

TRACE - The Transition Region and Coronal Explorer is a NASA Small Explorer (SMEX) mission to image the solar corona and transition region at high angular and temporal resolution. It has passband filters at 173 Å, 195 Å, 284 Å, 1600 Å with a spatial resolution of 0,5 arc sec, thes best at these wavelengths.

SDO - The Solar Dynamics Observatory is a NASA project composed of 3 different instruments: The Helioseismic and Magnetic Imager (HMI), the Atmospheric Imaging Assembly (AIA) and the Extreme Ultraviolet Variability Experiment (EVE). It is in operation since February, 2010.

Hinode -The Hinode spacecraft, originally called Solar B, was launched by the Japan Aerospace Exploration Agency in September 2006 to observe solar flares in more precise detail. Its instrumentation, supplied by an international collaboration including Norway, the U.K., the U.S., and Africa focuses on the powerful magnetic fields thought to be the source of solar flares. Such studies shed light on the causes of this activity, possibly helping to forecast future flares and thus minimize their dangerous effects on satellites and astronauts.

Examples of large solar flares

The most powerful flare ever observed was the first one to be observed, on September 1, 1859, and was reported by British astronomer Richard Carrington and independently by an independent observer named Richard Hodgson. The event is named the Solar storm of 1859, or the "Carrington event". The flare was visible to a naked-eye (in ''white light''), and produced stunning auroras down to tropical latitudes such as Cuba or Hawaii, and set telegraph systems on fire. The flare left a trace in Greenland ice in the form of nitrates and beryllium-10, which allow its strength to be measured today (New Scientist, 2005). Cliver & Salvgaard (2004) reconstructed the effects of this flare and compared with other events of the last 150 years. In their words: ''While the 1859 event has close rivals or superiors in each of the above categories of space weather activity, it is the only documented event of the last ∼150 years that appears at or near the top of all of the lists''.

In modern times, the largest solar flare measured with instruments occurred on November 4, 2003. This event saturated the GOES detectors, and because of this its classification is only approximate. Initially, extrapolating the GOES curve, it was pegged at X28. Later analysis of the ionospheric effects suggested increasing this estimate to X45. This event produced the first clear evidence of a new spectral component above 100 GHz. Other large solar flares also occurred on April 2, 2001 (X20), October 28, 2003 (X17.2 & X10), September 7, 2005 (X17), February 17, 2011 (X2). and August 10, 2011 (X6.9). In 1989, during solar cycle 22 two large flares occurred on March 6 (X15) (see: ''March 1989 geomagnetic storm'') and August 16 (X20) causing disruptions in electric grids and computer systems. A complete list is available at http://www.spaceweather.com/solarflares/topflares.html

Flare Spray

Flare sprays are a type of eruption associated with solar flares. They involve faster ejections of material than eruptive prominences, and reach velocities of 500 to 1200 kilometers per second.

Prediction

Current methods of flare prediction are problematic, and there is no certain indication that an active region on the Sun will produce a flare. However, many properties of sunspots and active regions correlate with flaring. For example, magnetically complex regions (based on line-of-sight magnetic field) called delta spots produce most large flares. A simple scheme of sunspot classification due to McIntosh is commonly used as a starting point for flare prediction. Predictions are usually stated in terms of probabilities for occurrence of flares above M or X GOES class within 24 or 48 hours. The U.S. National Oceanic and Atmospheric Administration (NOAA) issues forecasts of this kind.

See also

Aurora (astronomy)

Coronal mass ejection

Flare star

Gamma Ray Burst

Geomagnetic storm

March 1989 geomagnetic storm

Magnetic reconnection

Solar wind

Solar storm of 1859

References

Mewaldt, R.A., ''et al.'' 2005. Space weather implications of the 20 January 2005 solar energetic particle event. Joint meeting of the American Geophysical Union and the Solar Physics Division of the American Astronomical Society. May 23–27. New Orleans. Abstract.

Solar Flares NASA Video from 2003

Solar Flares Solar & Heliospheric Observatory Video from 2002

External links

Solar Cycle 24 and VHF Aurora Website (www.solarcycle24.com)

Solar Weather Site

Current Solar Flare - and geomagnetic activity in dashboard style (www.solar-flares.info)

STEREO Spacecraft Site

Early BBC report on the November 4, 2003 flare

Later BBC report on the November 4, 2003 flare

NASA SOHO observations of flares

Stellar Flares - D. Montes, UCM.

The Sun - D. Montes, UCM.

ASC / Alliances Center for Astrophysical Thermonuclear Flashes

'The Sun Kings', lecture by Dr Stuart Clark on the discovery of solar flares given at Gresham College, 12 September 2007 (available as a video or audio download as well as a text file).

An X Class Flare Region on the Sun - NASA Astronomy Picture of the Day

Sun trek website An educational resource for teachers and students about the Sun and its effect on the Earth

NASA - Carrington Super Flare NASA May 6, 2008

Archive of the most severe solar storms

Animated explanation of Solar Flares from the Photosphere (University of Glamorgan)

Mini documentary: How big are solar flares? A simplified explanation of the size of solar flares as compared to Earth.

Flare Category:Stellar phenomena Category:Space plasmas Category:Plasma physics

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Coordinates	21°58′29″N159°21′56″N
name	Michio Kaku
birth date	January 24, 1947
birth place	San Jose, California, United States
residence	New York City, New York, United States
nationality	American
field	Theoretical physics
work institutions	City University of New YorkNew York UniversityInstitute for Advanced Study
alma mater	Harvard University (B.S., 1968)University of California, Berkeley (Ph.D.,1972)
doctoral advisor	Stanley Mandelstam
known for	String field theory, Popular science
footnotes	}}

is an American theoretical physicist, the Henry Semat Professor of Theoretical Physics in the City College of New York of City University of New York, the co-founder of string field theory, and a "communicator" and "popularizer" of science. He has written several books on physics and related topics, he has made frequent appearances on radio, television, and film, and he writes extensive online blogs and articles.

Early life and education

Kaku was born in San Jose, California to Japanese immigrant parents. His grandfather came to the United States to take part in the clean-up operation after the 1906 San Francisco Earthquake. His father was born in California but was educated in Japan and spoke little English. Both his parents were put in the Tule Lake War Relocation Center, where they met and where his two brothers were born.

At Cubberley High School in Palo Alto, Kaku assembled an atom smasher in his parent's garage for a science fair project. At the National Science Fair in Albuquerque, New Mexico, he attracted the attention of physicist Edward Teller, who took Kaku as a protégé, awarding him the Hertz Engineering Scholarship. Kaku graduated ''summa cum laude'' from Harvard University in 1968 and was first in his physics class. He attended the Berkeley Radiation Laboratory at the University of California, Berkeley and received a Ph.D. in 1972, and in 1972 he held a lectureship at Princeton University.

During the Vietnam War, Kaku completed his U.S. Army basic training at Fort Benning, Georgia and his advanced infantry training at Fort Lewis, Washington. However, the Vietnam War ended before he was deployed as an infantryman.

Academic career

Kaku became a visiting professor at the Institute for Advanced Study in Princeton, and New York University. He currently holds the Henry Semat Chair and Professorship in theoretical physics at the City College of New York.

Kaku has had over 70 articles published in physics journals such as Physical Review, covering topics such as superstring theory, supergravity, supersymmetry, and hadronic physics. In 1974, along with Prof. Keiji Kikkawa of Osaka University, he authored the first papers describing string theory in a field form.

Kaku is the author of several textbooks on string theory and quantum field theory.

Popular science

Kaku is most widely known as a popularizer of science. He has written books and appeared on many television programs as well as film. He also hosts a weekly radio program.

Books

Kaku is the author of various popular science books.

''Physics of the Future''

''Physics of the Impossible''

''Hyperspace''

''Einstein's Cosmos''

''Parallel Worlds''

''Beyond Einstein'' (with Jennifer Thompson)

''Hyperspace'' was a best-seller and was voted one of the best science books of the year by both ''The New York Times'' and ''The Washington Post''. ''Parallel Worlds'' was a finalist for the Samuel Johnson Prize for non-fiction in the UK.

Radio

Kaku is the host of the weekly, one-hour radio program ''Explorations'', produced by the Pacifica Foundation's WBAI in New York. "Explorations" is syndicated to community and independent radio stations and makes previous broadcasts available on the program's website. Kaku defines the show as dealing with the general topics of science, war, peace, and the environment.

In April 2006, Kaku began broadcasting ''Science Fantastic'' on 90 commercial radio stations, the only nationally syndicated science program on commercial radio in the United States. It is syndicated by Talk Radio Network and now reaches 130 radio stations and America's Talk on XM. The program is formatted as a live listener call-in show, focusing on "futurology," which he defines as the future of science. Featured guests include Nobel laureates and top researchers on the topics of string theory, time travel, black holes, gene therapy, aging, space travel, artificial intelligence, and SETI. When Kaku is busy filming for television, ''Science Fantastic'' goes on hiatus, sometimes for several months. Kaku is also a frequent guest on many programs, where he is outspoken in all areas and issues he considers of importance, such as the program "Coast to Coast AM," where on 30 November 2007, he reaffirmed his belief that there is a 100% probability of extraterrestrial life in the universe.

Kaku has appeared on ''The Opie and Anthony Show'' a number of times, discussing popular fiction such as ''Back to The Future'', ''Lost,'' and the theories behind time-travel that these and other fictional entertainment focus on. Steven G. Spruill's novel ''The Janus Equation'', which describes the time travel of a post-op transsexual mating with her past self and thereby becoming father and mother to her present self, prompted Dr. Kaku's comment: "Well, you're in deep doo doo if that happens."

Television and film

Kaku has appeared in many forms of media and on many programs and networks, including ''Good Morning America'', ''The Screen Savers'', ''Larry King Live'', ''60 Minutes'', ''Nightline'', ''20/20'', ''Naked Science'', CNN, ABC News, CBS News, NBC News, Al Jazeera English, Fox News Channel, The History Channel, ''Conan'', The Science Channel, The Discovery Channel, TLC, ''Countdown with Keith Olbermann'', ''The Colbert Report'', ''The Art Bell Show'' and its successor, ''Coast To Coast AM'', ''BBC World News America'', ''The Opie & Anthony Show'', ''The Covino & Rich Show'', ''Head Rush'', ''The Late Show with David Letterman'', and ''Real Time with Bill Maher.

We Are the Guinea Pigs (1980)

Borders (1989)

''Synthetic Pleasures'' (1995)

Einstein Revealed (1996)

''Future Fantastic'' (1996)

''Stephen Hawking's Universe'' (1997)

Bioperfection: Building a New Human Race (1998)

Exodus Earth (1999)

Me & Isaac Newton (1999)

Space: The Final Junkyard (1999)

''Big Questions'' (2001)

''Parallel Universes'' (2001)

''Horizon'': "Time travel" (2003)

Robo sapiens (2003)

Brilliant Minds: Secret Of The Cosmos (2003)

''Nova'': "The Elegant Universe" (2003)

''Hawking'' (2004)

''The Screen Savers'' (2004)

''Unscrewed with Martin Sargent'' (2004)

''Alien Planet (2005)

''ABC News'' "UFOs: Seeing Is Believing" (2005)

''HARDtalk Extra'' (2005)

''Last Days on Earth'' (2005)

Obsessed & Scientific (2005)

''Horizon'': "Einstein's Unfinished Symphony" (2005)

Prophets of Science Fiction (2006)

''Time'' (2006)

''2057'' (2007)

''The Universe'' (2007)

Futurecar (2007)

''Attack of the Show!'' (2007)

''Visions of the Future'' (2008)

''Horizon'': "The President's Guide to Science" (2008)

Stephen Hawking: Master of the Universe (2008)

''Horizon'': "Who's Afraid of a Big Black Hole" (2009–2010)

''Sci Fi Science: Physics of the Impossible'' (2009–2010)

''Horizon'': "What Happened Before the Big Bang?" (2010)

''GameTrailers TV With Geoff Keighley'': "The Science of Games" (2010)

''How the Universe Works'' (2010)

''Through the Wormhole'' (2011)

In 1999, Kaku was one of the scientists profiled in the feature-length film ''Me and Isaac Newton'', directed by Michael Apted. It played theatrically in the United States, was later broadcast on national TV, and won several film awards.

In 2005, Kaku appeared in the short documentary ''Obsessed & Scientific.'' The film is about the possibility of time travel and the people who dream about it. It screened at the Montreal World Film Festival and a feature film expansion is in development talks. Kaku also appeared in the ABC documentary ''UFOs: Seeing Is Believing'', in which he suggested that while he believes it is extremely unlikely that extraterrestrials have ever actually visited Earth, we must keep our minds open to the possible existence of civilizations a million years ahead of us in technology, where entirely new avenues of physics open up. He also discussed the future of interstellar exploration and alien life in the Discovery Channel special ''Alien Planet'' as one of the multiple speakers who co-hosted the show, and Einstein's Theory of Relativity on The History Channel.

In February 2006, Kaku appeared as presenter in the BBC-TV four-part documentary ''Time'' which seeks to explore the mysterious nature of time. Part one of the series concerns personal time, and how we perceive and measure the passing of time. The second in the series deal with cheating time, exploring possibilities of extending the lifespan of organisms. The geological time covered in part three explores the ages of the earth and the sun. Part four covers the topics of cosmological time, the beginning of time and the events that occurred at the instant of the big bang.

On January 28, 2007, Kaku hosted the Discovery Channel series ''2057.'' This three-hour program discussed how medicine, the city, and energy could change over the next 50 years.

In 2008, Kaku hosted the three-hour BBC-TV documentary ''Visions of the Future'', on the future of computers, medicine, and quantum physics, and he appeared in several episodes of the History Channel's ''Universe'' series.

On December 1, 2009, he began hosting a 12-episode weekly TV series for the Science Channel at 10 pm, called ''Sci Fi Science: Physics of the Impossible'', based on his best-selling book. Each 30-minute episode discusses the scientific basis behind imaginative schemes, such as time travel, parallel universes, warp drive, star ships, light sabers, force fields, teleportation, invisibility, death stars, and even superpowers and flying saucers. Each episode includes interviews with the world's top scientists working on prototypes of these technologies, interviews with sci-fi fans, clips from science fiction movies, and special effects and computer graphics. Although these inventions are impossible today, the series discusses when these technologies might become feasible in the future.

In 2010, he began to appear in a series on the website Gametrailers.com called ''Science of Games'', discussing the scientific aspects of various popular video games such as ''Mass Effect 2'' and ''Star Wars: The Force Unleashed''.

Kaku is popular in mainstream media because of his knowledge and his accessible approach to presenting complex subjects in science. While his technical writings are confined to theoretical physics, his public speaking and media appearances cover a broad range of topics, from the Kardashev scale to more esoteric subjects such as wormholes and time travel. In January 2007, Kaku visited Oman. While there, he talked at length to select members of that country's decision makers. In an interview with local media, Dr Kaku elaborated on his vision of mankind's future. Kaku considers climate change and terrorism as serious threats in man's evolution from a Type 0 civilization to Type 1.

On October 11, 2010, Michio Kaku appeared in the BBC program "What Happened Before the Big Bang" (along with Laura Mersini-Houghton, Andrei Linde, Roger Penrose, Lee Smolin, Neil Turok, and other notable cosmologists and physicists), where he propounded his theory of the universe created out of nothing.

Social policy advocacy

Kaku has publicly stated his concerns over matters including the anthropogenic cause of global warming, nuclear armament, nuclear power and the general misuse of science. He was critical of the Cassini–Huygens space probe because of the of plutonium contained in the craft for use by its radioisotope thermoelectric generator. Conscious of the possibility of casualties if the probe's fuel were dispersed into the environment during a malfunction and crash as the probe was making a 'sling-shot' maneuver around earth, Kaku publicly criticized NASA's risk assessment. He has also spoken on the dangers of space junk and called for more and better monitoring. Kaku is generally a vigorous supporter of the exploration of outer space, believing that the ultimate destiny of the human race may lie in extrasolar planets; but he is critical of some of the cost-ineffective missions and methods of NASA.

Kaku credits his anti-nuclear war position to programs he heard on the Pacifica Radio network, during his student years in California. It was during this period that he made the decision to turn away from a career developing the next generation of nuclear weapons in association with Edward Teller and focused on research, teaching, writing and media. Kaku joined with others such as Helen Caldicott, Jonathan Schell, Peace Action and was instrumental in building a global anti-nuclear weapons movement that arose in the 1980s, during the administration of U.S. President Ronald Reagan.

Kaku was a board member of Peace Action and on the board of radio station WBAI-FM in New York City where he originated his long running program, ''Explorations,'' that focused on the issues of science, war, peace and the environment.

His remark from an interview in support of SETI, "We could be in the middle of an intergalactic conversation...and we wouldn't even ''know''.", is used in the third Symphony of Science installment "Our Place in the Cosmos".

Personal life

Kaku is married to Shizue Kaku and has one daughter.

Bibliography

References

External links

Getting Physical: Dr. Michio Kaku Explains Einstein's Genius

Russia Takes Aim at Asteroids, op-ed on asteroid defense, Wall St. Journal, Jan. 5, 2010

''The Skeptics' Guide To The Universe'' interview

Michio Kaku on National Public Radio

Category:City College of New York faculty Category:American physicists Category:American radio personalities Category:City University of New York faculty Category:Princeton University faculty Category:Futurologists Category:Harvard University alumni Category:American academics of Japanese descent Category:American people of Japanese descent Category:Japanese-American civil rights activists Category:Pacifica Radio Category:String theorists Category:Theoretical physicists Category:University of California, Berkeley alumni Category:People from San Jose, California Category:1947 births Category:Living people

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