Search This Blog

Friday, May 31, 2019

Comparison of Asian national space programs

From Wikipedia, the free encyclopedia

Several Asian countries have space programs and are actively competing to achieve scientific and technological advancements in space, a situation sometimes referred to as the Asian space race in the popular media as a reference to the earlier Space Race between the United States and the Soviet Union. Like the previous space race, issues involved in the current push to space include national security, which has spurred many countries to send artificial satellites as well as humans into Earth orbit and beyond. A number of Asian countries are seen as contenders in the ongoing race to be the pre-eminent power in space.

Asian space powers

Of the ten countries that have independently successfully launched a satellite into orbit, six are Asian: China, India, Israel, Japan, Iran and North Korea

China's first manned spacecraft entered orbit in October 2003, making China the first Asian nation to send a human into space. India expects to send Gaganauts to space in the Gaganyaan capsule by 2022.

While the achievements of space programs run by the main Asian space players (China, India, and Japan) pale in comparison to the milestones set by the former Soviet Union and the United States, some experts believe Asia may soon lead the world in space exploration. China has been the leader of Asia's space race since the beginning of the 21st century. The first Chinese manned spaceflight, in 2003, marked the beginning of a space race in the region. At the same time, the existence of a space race in Asia is still debated due to the non-concurrence of space milestone events like there was for the United States and the Soviet Union. Japan for example was the first power on Earth to get a sample return mission from an asteroid. There was however some concurrence between China and India to see which of those two could be the first to launch a probe to the Earth's moon back in the late 2000s decade. China, for example, denies that there is an Asian space race. In January 2007 China became the first Asian military-space power to send an anti-satellite missile into orbit, to destroy an aging Chinese Feng Yun 1C weather satellite in polar orbit. The resulting explosion sent a wave of debris hurtling through space at more than 6 miles per second. A month later, Japan's space agency launched an experimental communications satellite designed to enable super high-speed data transmission in remote areas.

After successful achievement of geostationary technology, India's ISRO launched its first Moon mission, Chandrayaan-1 in October 2008, which discovered ice water on the Moon. India then launched on 5 November 2013 its maiden interplanetary mission, the Mars Orbiter Mission. The primary objective is to determine Mars' atmospheric composition and attempt to detect methane. The spacecraft completed its journey on 24 September 2014 when it entered its intended orbit around Mars, making India the first Asian country to successfully place a Mars orbiter and the only country in history to do so in the first attempt. ISRO became the fourth space agency in the world to send a spacecraft to Mars, only behind NASA, ROSCOSMOS, and ESA.India carried out its Anti-satellite testing named 'Mission Shakti' in March 2019,thus making it fourth nation in the world to do so and have such missile technology. 

In addition to increasing national pride, countries are commercially motivated to operate in space. Commercial satellites are launched for communications, weather forecasting, and atmospheric research. According to a report by the Space Frontier Foundation released in 2006, the "space economy" is estimated to be worth about $180 billion, with more than 60% of space-related economic activity coming from commercial goods and services. China and India propose the initiation of a commercial launch service.

China

China has a space program with an independent human spaceflight capability. It has developed a sizable family of successful Long March rockets. It has launched two lunar orbiters, Chang'e 1 and Chang'e 2. On 2 December 2013, China launched a modified Long March 3B rocket, with Chang'e 3 Moon lander and its rover Yutu on-board toward the Moon and successfully performed soft landing and rover operations, becoming the third country to do so. It also has plans to retrieve samples by late 2017. In 2011, China embarked on a program to establish a manned space station, starting with the launch of Tiangong 1 and followed by Tiangong 2 in 2016. China attempted to send a Mars orbiter (Yinghuo-1) in 2011 on a joint mission with Russia, which failed to leave Earth orbit. Nevertheless, the 2020 Chinese Mars Mission with an orbiter, a lander and a rover has been approved by the government and is aiming a launch date in the year 2020. China has collaborative projects with Russia, ESA, and Brazil, and has launched commercial satellites for other countries. Some analysts suggest that the Chinese space program is linked to the nation's efforts at developing advanced military technology.

China's advanced technology is the result of the integration of various related technological experiences. Early Chinese satellites, such as the FSW series, have undergone many atmospheric reentry tests. In the 1990s China had commercial launches, resulting in more launch experiences and a high success rate after the 1990s. China has aimed to undertake scientific development in fields like Solar System exploration. China's Shenzhou 7 spacecraft successfully performed an EVA in September 2008. China's Shenzhou 9 spacecraft successfully performed a manned docking in June 2012. Furthermore, China's Chang'e 2 explorer became the first object to reach Sun-Earth Lagrangian point in August 2011 and also the first probe to explore both Moon and asteroid by making a flyby of the asteroid 4179 Toutatis. China has launched DAMPE, the most capable dark matter explorer to date in 2015, and world's first quantum communication satellite QUESS in 2016.

India

India's interest in space travel began in the early 1960s, when scientists launched a Nike-Apache rocket from TERLS, Kerala. Under Vikram Sarabhai, the program focused on the practical uses of space in increasing the standard of living. Remote sensing and communications satellites were placed into orbit.

The first Indian to travel in space was Rakesh Sharma, who flew aboard Soyuz T-11, launched April 2, 1984, from erstwhile USSR.

Just a few days after China said that it would send a human into orbit in the second half of 2003, Indian Prime Minister Atal Bihari Vajpayee publicly urged his country's scientists to work towards sending a man to the Moon. It successfully sent its probe to the Moon in October 2008 and is planning its second Moon mission, Chandrayaan-2 for 2019.

ISRO launched its Mars Orbiter Mission on November 5, 2013 (informally called "Mangalyaan") which successfully entered into the orbit around Mars on 24 September 2014. India is the first in Asia and fourth in the world to perform a successful Mars mission. It is also the only one to do so on the first attempt and at a record low cost of $74 million.

ISRO has demonstrated its re-entry technology and till date has launched as many as 175 foreign satellites belonging to global customers from 20 countries including US, Germany, France, Japan, Canada, U.K. All of these have been launched successfully by PSLVs so far, gaining significant expertise in space technologies. In June 2016, India set a record by launching 20 satellites simultaneously. The PSLVs are also one of world's most reliable launch vehicles which clocked its 35th successful mission (39 total) in a row as of February 2017, thus having success rate of nearly 90%. 

India broke the world record by successfully placing 104 satellites (almost tripling the Russian record of 37) in Earth Orbit on 15 February 2017 on a single rocket launch (PSLV-C37).

Recent reports indicate that human spaceflight is planned with a spacecraft called Gaganyaan for December 2021 on a home-grown GSLV-III rocket. ISRO is also planning to send orbiters to Venus, Mars and Jupiter or comets and asteroids in the near future.India have successfully launched anti-satellite missile , becoming only the fourth country to do so.

Japan

The H-IIA F11 launch vehicle lifts off from Tanegashima Space Center in Japan
 
Japan has been cooperating with the United States on missile defence since 1999. North Korean nuclear and Chinese military programs represent a serious issue for Japan's foreign relations. Japan is working on military and civilian space technologies, developing missile defence systems, new generations of military spy satellites, and planning for manned stations on the Moon. Japan started to construct spy satellites after North Korea test fired a Taepodong missile over Japan in 1998. The North Korean government claimed the missile was merely launching a satellite to space, and accused Japan of causing an arms race. The Japanese constitution adopted after World War II limits military activities to defensive operations. On May 2007 Prime Minister Shinzo Abe called for a bold review of the Japanese Constitution to allow the country to take a larger role in global security and foster a revival of national pride. Japan has not yet developed its own manned spacecraft and does not have a program in place to develop one. The Japanese space shuttle HOPE-X, to be launched by the conventional space launcher H-II, was developed but the program was postponed and eventually cancelled. Then the simpler manned capsule Fuji was proposed but not adopted. Pioneer projects of single-stage to orbit, reusable launch vehicle horizontal takeoff and landing ASSTS and vertical takeoff and landing Kankoh-maru were developed but have not been adopted. A more conservative new (JAXA manned spacecraft) project is proposed to launch by 2025 as part of the Japanese plan to send manned missions to the Moon. Shin'ya Matsuura is doubtful about the Japanese manned Moon project, and suspects the project is a euphemism for participation in the American Constellation program. JAXA planned to send a humanoid robot (such as ASIMO) to the Moon.

Other players

Iran

Iranian Simorgh (rocket) SLV
 
Iran has developed its own satellite launch vehicle, named the Safir SLV, based on the Shahab series of IRBMs. On 2 February 2009, Iranian state television reported that Iran's first domestically made satellite Omid (from the Persian امید, meaning "Hope") had been successfully launched into low Earth orbit by a version of Iran's Safir rocket, the Safir-2. The launch coincided with the 30th anniversary of the Iranian Revolution. Iran is also developing a new launch vehicle Simorgh (rocket).

Israel

Shavit, the Israeli orbital launch system
 
Israel became the tenth country in the world to build its own satellite and launch it with its own launcher on 19 September 1988. Israel launched its first satellite, Ofeq-1, using an Israeli-built Shavit three-stage launch vehicle. The launching was the high point of a process that began in 1983 with the establishment of the Israel Space Agency under the aegis of the Ministry of Science. Space research by university-based scientists began in the 1960s, providing a ready-made pool of experts for Israel's foray into space. Since then, local universities, research institutes, and private industry, backed by the Israel Space Agency, have made progress in space technology. The agency's role is to support "private and academic space projects, coordinate their efforts, initiate and develop international relations and projects, head integrative projects involving different bodies, and create public awareness for the importance of space development."

North Korea

North Korea has many years of experience with rocket technology, which it has passed along to Pakistan and other countries. On December 12, 2012, North Korea placed its first satellite in orbit with the launch of Kwangmyŏngsŏng-3 Unit 2. On 12 March 2009 North Korea signed the Outer Space Treaty and the Registration Convention, after a previous declaration of preparations for the launch of Kwangmyongsong-2. North Korea twice announced satellite launches: Kwangmyŏngsŏng-1 on 31 August 1998 and Kwangmyŏngsŏng-2 on 5 April 2009. Neither of these claims were confirmed by the rest of the world, but the United States and South Korea believe there were tests of military ballistic missiles. The North Korean space agency is the Korean Committee of Space Technology, which operates the Musudan-ri and Tongch'ang-dong Space Launch Center rocket launching sites and has developed the Baekdusan-1 and Unha (Baekdusan-2) space launchers and Kwangmyŏngsŏng satellites. In 2009 North Korea announced several future space projects, including manned space flights and the development of a manned partially reusable launch vehicle. The successor to the Korean Committee of Space Technology, National Aerospace Development Administration (NADA) successfully launched an Unha-3 launch vehicle in February 2016, placing the Kwangmyŏngsŏng-4 satellite in orbit.

South Korea

South Korea is a newer player in the Asian space race. In August 2006 South Korea launched its first military communications satellite, the Mugunghwa-5. The satellite was placed in geosynchronous orbit and collects surveillance information about North Korea. The South Korean government is spending hundreds of millions of dollars in space technology and was due to launch its first space launcher, the Korea Space Launch Vehicle, in 2008. South Korea's government justifies the cost for reasons of long-term commercial benefits and national pride. South Korea has long seen North Korea's significantly longer missile range as a serious threat to its national security. With the nation's first astronaut launched into space, Lee So-yeon, South Korea gained confidence in entering the Asian space race. They have completed the construction of Naro Space Center. South Korea is now attempting to build satellites and rockets with local technology. South Korea is pursuing a space program that could defend the peninsula while lessening their dependency on the United States.

Turkey

As of 2012 Turkey was developing its own military satellite. The first Göktürk satellite is planned to be launched in 2013. The Turkish satellite is planned to be capable of taking satellite images of greater than two meters per pixel resolution, thus making Turkey the second nation in the world capable of such a feat, after the United States. Turkey is also developing an orbital launch system known as UFS.

Other nations and regions

Other minor space fairing countries are Bangladesh Indonesia, Malaysia and Pakistan. LAPAN is responsible for long-term civilian and military aerospace research Indonesia. For over two decades, it has managed satellites and domain-developed small scientific-technology satellites Lapan and telecommunication satellites Palapa, which were built by Hughes (now Boeing Satellite Systems) and launched from the US on Delta rockets or from French Guiana using Ariane 4 and Ariane 5 rockets. It has also developed sounding rockets and has been trying to develop small orbital space launchers. The LAPAN A1 in 2007 and LAPAN A2 satellites were launched by India in 2015. Indonesia has undertaken programs to develop and use their own small space launch vehicle Pengorbitan (RPS-420).

On 7 June 1962, with the launch of the Rehbar-I rocket, Pakistan became the tenth country in the world to successfully conduct the launch of an unmanned spacecraft. SUPARCO has launched a number of sounding rockets. Pakistan's first satellite, Badr-I was launched from China in 1990, Badr-B in 2001 from Baikonur Cosmodrome using a Ukrainian Zenit-2 rocket, followed by Paksat-1R in 2011 which was contracted and actually built and launched by China, was Pakistan's first communication satellite. Under its Space programme 2040, Pakistan aims to operate five geostationary and six low earth orbit satellites. Development of any satellite launch vehicle is not planned. 

With the launch of Bangabandhu-1 satellite purchased abroad, Bangladesh began operating its first communication satellite in 2018. Bangladesh Space Agency intends to launch satellites after 2020. Bangladesh's government has stressed that the country seeks an "entirely peaceful and commercial" role in space.

NewSpace

From Wikipedia, the free encyclopedia

NewSpace, or new space, is a movement and philosophy encompassing a globally emerging private spaceflight industry. Specifically, the term is used to refer to a global sector of new aerospace companies and ventures working independently of governments and traditional major contractors to develop faster, better, and cheaper access to space and spaceflight technologies, driven by commercial, as distinct from political or other, motivations to broader, more socioeconomically-oriented, ends.
 
Investment bank Morgan Stanley expects 2019 to show "key milestones and catalysts [in the new space sector]" and advises its customers to "pay attention to space companies".

Meaning of "NewSpace"

The term NewSpace has clearly meant somewhat different things to various people over the years of the 2000s when the term picked up usage.

Satsearch conducted research to better understand how the term NewSpace is used across the space industry and in popular understanding globally during 2018–19. They reported that the common consensus is that "NewSpace is an approach that focuses on lowering the barriers to entry to space industry, by providing cheaper access to space [and] more high-quality and affordable data from space that can be put to use here on Earth, for the benefit of scientists and the general public. ... [One] of the major characteristics of the NewSpace era [is the] the fundamental shift from an industry which was heavily dependent on government agencies (and taxpayers’ money) to a more agile and an independent private sector that relies on innovation, working with much smaller budgets than the early space industry.

HobbySpace, awarded the 2007 ‘Best Presentation of Space’ by the Space Frontier Foundation, came up with the following:
list of characteristics which would help determine whether a particular endeavor is considered as a NewSpace approach. They mainly include the following:
  1. Focus on cost reductions
  2. An assurance that the low costs will pay off
  3. Ensuring incremental development
  4. Foray into commercial markets with high-consumer rates
  5. Primary emphasis on optimizing operations
  6. At the heart of it all, innovation

History

The Space Race, which began in the mid-1950s and gave birth in earnest to spaceflight, was famously a manifestation of the then larger politico-economic competition between capitalism (represented by the United States) and communism (represented by the former Soviet Union). For this reason, from the very beginning, the American business establishment—particularly those bellwether private firms directly involved in the U.S. space program—has championed the private development of space and space activity. In 1961, writing as one of the deans of the American business establishment, Ralph J. Cordiner, then chairman of General Electric (a blue-chip, charter-prime contractor to NASA and the U.S. space program), contributed a chapter titled "Competitive Private Enterprise in Space" to the anthology Peacetime Uses of Outer Space. While recognizing at the time the realities of having to initially rely on the U.S. government's vast and convenient organization, resources, and power in order to effectively address the immediate Soviet space challenge, Cordiner nonetheless advocated private sector dominance—ultimately—of space activity, consistent with textbook American capitalist ideals.

Syncom, Hughes Aircraft Company's commercial communications satellite system, was originally conceived as a direct competitive response by American private industry to the Soviets' successful deployment of Sputnik in 1957, the Cold War event that triggered the Space Race. While Syncom was eventually successfully deployed in 1963, Dr. Harold Rosen, the Hughes engineer responsible for developing, championing, and spearheading Syncom (also brother of Ben Rosen, a pioneering Silicon Valley venture capitalist and entrepreneur, and Wall Street technology analyst), cited a general lack of confidence in the U.S. government's early launch capabilities. He later explained the Syncom project's lengthy gestation period:
This was not the most auspicious time [late 1950s] to propose a commercial space program...The most vivid impression most people then had of space-related activities was of rockets blowing up at Cape Canaveral.

1980s: U.S. commercial space policy and enabling legislation

Notwithstanding the free-enterprise sentiments and preferences of American industry, space remained a firmly government-controlled and -directed endeavor well after the capstone Apollo moon landing in 1969. The term "alt.space" was first used in the early 1980s to describe companies that were at last beginning to take up Cordiner's mantle and make serious efforts to reach outer space without needing or relying on the cooperation of NASA or other governmental agencies (or, by extension, even their major contractors); efforts which were catalyzed by an historic shift in U.S. policy favoring private space activity, culminating in the landmark Commercial Space Launch Act of 1984. Beyond the terminology—"alt.space", "private space", "NewSpace," or "new space"—since the 1980s, the philosophy of various organizations (such as the Space Frontier Foundation in the United States) has been one of "extolling the virtues of Solar System settlement and operating independent of bureaucratic government programs".

1990s: Post-Soviet U.S.-Russian private space ventures

The seeds of today's NewSpace were brought to fruition by the collapse of the former Soviet Union in 1991 and the releasing of that former rival-superpower's iconic, state-owned, and otherwise mature and proven space assets, technologies, capabilities, and services onto the world's private markets with the assistance of a handful of largely American private firms; notably these core-four: International Launch Services (f/k/a Lockheed-Khrunichev-Energia Int'l; Lockheed Martin JV; Proton; est. 1993); Commercial Space Management Co. (CSMC; Energia, Zenit, RD-170; est. 1993); Sea Launch (Boeing JV; Zenit; est. 1995); and MirCorp (Mir, Soyuz, Progress; est. 1999). Until that moment in world industrial history, no private business enterprise or entrepreneur could rightly conceive of, for example, leasing—or possibly owning and operating—an orbiting space station, such as Mir, or even just ordering a space launch in the ordinary course of business.

(Until then, even for a telecommunications giant, like AT&T, placing a commercial communications satellite in orbit, for example, was a fairly monumental undertaking. Contrast that with today, when a $100 million space launch vehicle can now be specified, built, priced, ordered, and eventually even launched online through, for example, United Launch Alliance's RocketBuilder website.)

Once that industry-wide mental block was removed—once the ease (relatively speaking) and normalization of planning and conducting space activities began to dawn on private industry—the animal spirits of aerospace capitalism were roused, entrepreneurial vision and imagination started to abound, and NewSpace began to take shape in earnest. This set off today's competitive, industry-wide, virtuous cycle of "faster, better, cheaper" (a project and systems management philosophy pioneered in the space field by NASA); and otherwise paved the way to today's generally far more vibrant and conducive space-business environment—whether or not involving Russian space resources, at this point—where entrepreneurs, investors, regulators, lawmakers, supranational organizations, non-governmental organizations (NGOs), the media, and other key ecosystem participants are now able to deal with privately conducted, for-profit space activity more rationally, practically, and cost-efficiently than ever before. (Wernher von Braun summed up the historical institutional-bureaucratic cautiousness toward space activity in general by famously quipping, "We can lick gravity, but sometimes the paperwork is overwhelming.")

In his 2016 Wall Street Journal review of Julian Guthrie's book How to Make a Spaceship: A Band of Renegades, an Epic Race, and the Birth of Private Spaceflight, Gregg Easterbrook highlighted the seminal importance of these often overlooked post-Soviet private space efforts in enabling and shaping today's NewSpace. How to Make a Spaceship centers largely around the efforts of space entrepreneur, Peter Diamandis, and his Ansari X Prize won in 2004 by the SpaceShipOne team led by American aerospace engineer Burt Rutan, and funded by Microsoft co-founder and billionaire Paul Allen (SpaceShipTwo was then funded by British billionaire and industrialist Sir Richard Branson and his Virgin Galactic). To set the stage, Guthrie retraces the private space industry's development path; however, according to Easterbrook:
Mr. Diamandis wasn't the sole entrepreneur to pursue private space flight [early on]. Ms. Guthrie covers other, peculiar attempts.... Neglected in Ms. Guthrie's account is Sea Launch [archetypal post-Soviet Boeing JV with Russians and others], the first private project to send heavy objects into orbit, including, in 2001, the big satellites Rock and Roll, the initial broadcast towers of XM Radio. Every bit as eccentric as the efforts that How to Make a Spaceship describes, Sea Launch fired large [Russian Zenit] rockets from a ship at the equator—equatorial water is the ideal position for space access—compiling a record of 32 successes, three failures and one satellite functioning but in the wrong orbit.
In 2001, the FAA/AST confirmed that NewSpace pioneer Sea Launch was indeed "[t]he first privately financed, working launch system and infrastructure...".

Near the end of the 1990s, favored by strong public policy, and spurred on by the foundational success of these post-Soviet U.S.-Russian private space ventures, there was a dramatic increase in companies engaging in this process, leading to common usage of the phrase "new space companies." "NewSpace" (most prominently), "entrepreneurial space," and "commercial space" are now the most commonly used terms, though "alt.space" was still seen occasionally as late as 2011.

2000s: Silicon Valley-style entrepreneurial space initiatives

Things changed further in the early 2000s as Elon Musk formed SpaceX with significantly more private capital while he articulated a strong and consistent vision of the "colonization of space, beginning with Mars."

However, one company in a worldwide milieu of government-driven spaceflight activities simply did not cement a movement. This began to change with the increasingly public revelations and pronouncements of Blue Origin after 2014. Even though the company was formed about the same time as SpaceX, it had maintained a very low profile in its first decade-and-a-half of existence. By 2016, both of these private companies, with billion-US-dollar-plus backing by committed investors, were successfully vertically landing and reusing space launch vehicles. Both companies are building large reusable orbital launch systems that will utilize currently-under-development rocket engines that are each at least four years along in development, and are already in use or under development test on ground test stands, all with a focus on radically lowering the price of carrying people and cargo to space.

Beginning on November 23, 2015, Blue Origin successfully demonstrated the repeated reuse of a rocket for the first time ever, by completing five suborbital, vertical takeoff and landing (VTOL) flights of the same New Shepard rocket; a feat for which Blue Origin was awarded the prestigious 2016 Robert J. Collier Trophy.

On March 30, 2017, SpaceX successfully relaunched a previously flown orbital-class rocket (Falcon 9) for the first time in history, an achievement many compare in significance to that of the Wright brothers' first flight. Celebrated astrophysicist Neil deGrasse Tyson described the underlying economic importance of SpaceX's otherwise technical milestone:
Any demonstration of rocket reusability is a good thing. [...] When we fly on a Boeing 747 across great distances, we don't throw it away and roll out a new one. Reusability is arguably the most fundamental feature of affordable expensive things.
Echoing deGrasse Tyson's post-flight sentiments, former NASA official (and current engineering dean at the University of Colorado Boulder) Bobby Braun "compared the [Falcon 9] rocket to the first successful commercial airliner, the Boeing 707, which ushered in the jet age".

Industry verticals

While NewSpace is currently a primarily horizontal market phenomenon or force which cuts across or "converges" many traditional, existing space-industry "verticals" (i.e., vertical markets)—including spacecraft, launch vehicles and services, scientific research, etc.—the ultimate promise of NewSpace is that it can become a true general purpose technology (or meta-technology), uniquely enabling the creation of new, emerging, and even once-unimaginable verticals, including:

Governmental environment

Regulatory schemes

In the United States, NewSpace firms and activities are primarily regulated by the FAA's Office of Commercial Space Transportation (generally referred to as FAA/AST). However, given the intersection of potentially many and varied agency-interests at stake in any NewSpace venture (e.g., FAA, FCC, NOAA, DOD, NASA, FDA, DOE, DOC, etc.), and the sheer infancy of NewSpace as an industry, it appears a comprehensive and userfriendly U.S. regulatory scheme has yet to be developed and put into place to the general satisfaction of NewSpace players:
Right now there are significant gaps in the U.S. government's regulatory authority and licensing process for newly emerging commercial space ventures [i.e., NewSpace firms and projects]. Processes exist for some ventures, but not for others. [...] In many cases, it's not clear what agency, if any, a commercial firm should go through to get approval. [...] The lack of clear rules, authorities, and process is needlessly driving up risk for these firms. Worse yet, it may lead some of them to move to countries where there is greater regulatory clarity or less oversight.

Laws and regulations

International treaties

Business ecosystem

Active companies

Dormant or defunct companies (e.g., industry pioneers)

Other organizations

Governing bodies

Academic institutions

Media and events

Algorithmic information theory

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Algorithmic_information_theory ...