text:
Talk:Software patent

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Article title
In my perception, the designation "software patent" is informal. Yes, imho there must be a Wikipedia artice under that name, simply because this (informal) designation is widely used. But at the same time, due to its informal nature, there is no reason to attempt a definition. The scope of the issue is best defined as: what patent applications may be affected by the exclusion in art. 52 EPC? For America, this definition may not be satisfactory, but then again in American patent law, software patentability never was an issue, at least not under this name. The Americans rather objected the patentability of "mathematical algorithms" for several decades.

There is reason to argue that "software patent" is not just informal, but even incorrect terminology at an "ontological" level. Because patent law basically only covers "tricks", not the resulting realisations, conceivably a patent may be implementable both in hardware and software. Rbakels (talk) 13:05, 28 May 2009 (UTC)

new zealand
Should we make a section that describes patent law in New Zealand and how software patents are illegal there by a recent law passed. —Preceding unsigned comment added by 122589423KM (talk • contribs) 03:34, 28 July 2010 (UTC)
 * Can you provide a source? GDallimore (Talk) 10:46, 28 July 2010 (UTC)

citations http://www.itwire.com/it-policy-news/government-tech-policy/40451-new-zealand-says-no-to-software-patents http://www.geekosystem.com/new-zealand-bans-software-patents/ http://www.cpaglobal.com/newlegalreview/4617/south_pacific_cousins_part_way http://www.tgdaily.com/business-and-law-features/50667-new-zealand-bans-software-patents —Preceding unsigned comment added by 122589423KM (talk • contribs) 12:58, 29 July 2010 (UTC)

Patent for fun?
From the Why software patents are a joke, literally article by Ed Burnette, it says that: A former Sun/Oracle employee admits that developers created patents in a contest to see who could get the goofiest patent through the system. Now Oracle is using patents from the same folks as the basis for its lawsuit against Google. How much that the software patent has a "knee-jerking" history. Perhaps there is a need to address this. Komitsuki (talk) 20:07, 24 August 2010 (UTC)

Earl Killian has 26 software patents and he's up for deletion
I think (my POV) that software patents are important -- that a patent in and of itself constitutes a valid secondary source since it's validation by a second (impartial) entity -- a government agency charged with saying that a method or process is new. If you are a software writer, patent attorney, or work in the computer industry or otherwise have a view on this, I urge you to weigh in on the discussion of Articles for deletion/Earl Killian.--Tomwsulcer (talk) 17:00, 27 November 2010 (UTC)
 * 846 patents might be notable. 26 isn't. GDallimore (Talk) 18:05, 27 November 2010 (UTC)
 * Respectfully disagree. One software patent would be notable depending on what it did. Where did you get the figure 846 from? Are you joking?--Tomwsulcer (talk) 21:27, 27 November 2010 (UTC)
 * Did you bother following the link I've provided? And, yes, one patent on one worthwhile invention could make someone notable, but you've failed to provide any evidence that any of these inventions are worthwhile or notable. GDallimore (Talk) 20:49, 28 November 2010 (UTC)
 * Maybe you have a different perspective if you are, in fact, a patent attorney. Perhaps for you patents are like chocolate bars or dimestore candy. But for the rest of us, you know, everyday people, a patent is a big thing -- a new invention, a new capability or process or method which advances human capability, a marker deeming an invention worthy of legal protection by the government. If somebody has 26 patents, I respect that. I believe the computer industry has been evolving at such a frantic pace that none of us knows what this means yet, but perhaps we will in time. What I am claiming is that a patent is, in and of itself, notable. I'm only a handyman so I doubt I could explain what Killian's inventions do; but I bet there are people reading this, here on this page, who could explain what Killian's inventions are and why they're significant. I followed your link and I was enlightened about the inventors with hundreds of inventions, led by Thomas Edison; thank you for sharing this. I still believe patents are an excellent example of Wikipedia's secondary sources -- one step removed, with an impartial referee looking at primary materials (inventions) and making a judgment -- an analytical claim. So I think it's perfectly reasonable to include computer scientists with multiple patents in Wikipedia. One other thing about Killian -- with two others, he founds a company (QED) -- a few years later, it's valued at several billion dollars (according to NY Times) -- isn't that notable?--Tomwsulcer (talk) 23:15, 28 November 2010 (UTC)
 * This thread is getting rather off-topic from software patents, but I should note that patents aren't secondary sources by any means, nor are they necessarily a "big thing". At the risk of over generalizing: anything that's new can be patented, even if it's inefficient, impractical, or downright idiotic. Second, patents don't comment on the invention or the inventor, they are drafted by the inventor or their agents and largely edited by the same and so would be primary sources. VernoWhitney (talk) 16:06, 29 November 2010 (UTC)

Comparison to Copyright
@GDallimore, RE: (→Overlap with copyright: "very" limited protection? POV and not correct - it's just less protection than patents, but that point is already being made in a more neutral way in the rest of this section. Discuss before adding these materials back). I have 3 points I ask you to reply to:

1) Instead of wholesale deletion, may I suggest that you correct what you believe to be biased? For example omit the word "very", that would still be satisfactory to this contributor.

2) Under copyright law, when a work is modified to a sufficient degree, for example symbol renaming and flow change, please clarify if it is your belief that the original author will have little or no difficulty proving the derivative work was their own.

3) In the contributions I made, and points you feel were redundant, please cite where in the topic those points were already made (

a) comparison to other copyright; b) ease of obfuscation to circumvent copyright; 3) advantages if any that patents offer given #b; — Preceding unsigned comment added by Kensystem (talk • contribs) 01:18, 25 February 2011 (UTC)

 * 1. I removed your edits sentence by sentence explaining why I thought they were appropriate. I could see nothing salvagable in them as they stood, but maybe some discussion here could lead to improvement before going back to amend the article. That is the typical approach to editing wikipedia see WP:BRD.
 * 2. "symbol derivation and flow change" is a very specific example of how code can be modified in what is intentionally a generalised section and just looked entirely wrong as an addition to the article from a verbiage perspective. In any event, the onus is not on be to confirm my belief, but on you to provide reliable sources to back up your edits. Also, the difficulties of proving copyright infringement are general to copyright as a whole and need not be discussed in detail here. Finally, given that proving patent infringement can take a multi-million pound law-suit, I don't think it's fair to suggest that proving patent infringement is "easy".
 * 3. From the article "[Copyright] allows the creator to prevent another entity from copying the program and there is generally no need to register code in order for it to be copyrighted. // Patents, on the other hand, give their owners the right to prevent others from using a claimed invention, even if it was independently developed and there was no copying involved." I think that says what you were trying to say in a more neutral manner.
 * a. There is no need to compare to "other" copyright. There is no difference in the way copyright protects one form of expression over another. And if there is, it does not appear to be relevant here. And even if it were, it would need a source, not just your opinion.
 * b. Even if it were particularly relevant to this article, it requires a source as discussed above.
 * I think that covers everything. The key thing is: don't just write stuff, find reliable sources relevant to the topic and add stuff based on those sources. GDallimore (Talk) 01:33, 25 February 2011 (UTC)

@GDallimore,

 * RE #2, If you feel it being a "specific example" warrants wholesale deletion from that section, then I ask you to a:: suggest where else in the Software Patents article to place the Copyright comparison, or b:: CHANGE the contribution to either show more generalized examples of how copyright can be circumvented or else add additional examples, so that the reader is certain to be aware of them.

 * RE #3, I respectfully disagree, nowhere in this article is it made clear that copying of source code then changing symbols and flow is one (possible of many) trivial and effective way to mask a plagiarism, and that this is a key reason inventors obtain software patents, and; b:: this section "comparison to copyrights" is appropriate to point out such a differentiation.

 * RE #3.a, Music, film and video, literature, software etc, are very different mediums, and each has very different means of expression by nature, and so the laws and tools for determining thresholds of copyright infringement differ: Authors of both Music and Software may desire to retain exclusive rights to their software, but the analysis to determine infringement/plagiarism are very, very different. Moreover modern obfuscation software make that analysis very difficult. See the 4th paragraph and points here: http://www.fair-opinion.com/Current%20Issues.shtml.

I also suggest that the inclusion of Music and other copyright expressions, is appropriate as it highlights to lay readers why Patents are generally applied to to technical creations, whereas Copyright may be sufficient for Music etc where non-specialist can determine if there is sufficient resemblance. — Preceding unsigned comment added by Kensystem (talk • contribs) 02:54, 25 February 2011 (UTC)

 * The link you provide is not to a reliable source, I'm afraid. GDallimore (Talk) 12:18, 25 February 2011 (UTC)

 * That link is a summary overview practical concerns of identifying plagiarism. Do you regard the following article, or prior case law withing it, as reliable references; and also that the general that software copyright infringement analysis is very different from other forms of expression, AND from patents)?:

http://www.ifosslr.org/ifosslr/article/download/30/54 pages 24-30 contains references to cases and also terms that address how software specifically is analyzed for copyright violation, and specific methods to determine to what degree "copied work" must be "substantially altered" before an infringer to claim separate authorship. Specifically:

Abstraction Filtration Comparison, Literal vs. Nonliteral Copying, Merger Exception. See also "Nimmer warns of the pitfalls in use of a 'look and feel' type of test"

Kensystem (talk) 16:06, 25 February 2011 (UTC)

 * This would make an excellent addition to an article about Copyright infringement of software, which needs a lot of work. But there's no mention of patents in that article, so no mention of how these trials and tribulations of copyright infringement relate to the corresponding issue of patent availability and infringement. GDallimore (Talk) 23:47, 25 February 2011 (UTC)

 * Perhaps Copyright infringement of software is one place for further elaboration, but since as you say it does not compare/contrast patents, and this article's Overlap with Copyright already does, I will suggest this location is most appropriate to list specific use-cases (libraries vs UI etc), case law, derived works, combination of user interface elements, and more general concerns and effects of Copyright's substantial modification limitation, obfuscation tools -- so that a reader can distinguish how patents and copyright differ in protection. To that end do you object to placing those points in this Overlap with Copyright section, or, to place it in a new section perhaps entitled Practical differences from copyright?

Kensystem (talk) 05:40, 26 February 2011 (UTC)

 * Yes, OVERLAP with patents. Since the source you cite doesn't mention patents, it can't comment on the overlap between the two forms of protection. I meant to add a link to that other article last night so that people can read more about copyright in software should they wish, but this article is primarily about patents, not copyright. GDallimore (Talk) 12:38, 26 February 2011 (UTC)

 * The source I cited makes clear through example and case law, the limits of copyrights. Currently there is NO MENTION that substantial similarity, and tools that facilitate overcoming it, are IMPORTANT considerations to authors when deciding how to protect their invention. Adding theses references provide literal examples to readers of where copyrights are limited.

 * Do you object to both, specific examples of copyright boundary, and to illustration of ways to overcome substantial similarity?

Kensystem (talk) 17:17, 26 February 2011 (UTC)

 * Using multiple accounts is liable to get you blocked from editing. GDallimore (Talk) 11:55, 1 March 2011 (UTC)

 * Hi GDallimore - What other account are you suggesting Kensystem is using? Also will you please reply to Kensystem's last question? Raymondjo (talk) 16:46, 3 March 2011 (UTC)

 * Stop protesting innocence. There is no answer to give to a question that doesn't make sense. Perhaps another editor would like to weigh in. GDallimore (Talk) 20:59, 3 March 2011 (UTC)

Every computer professional but only few patent attorney know that overlapping concurrent property rights are a threat to innovation. This is very clear since Samuelsonss Manifesto http://cseserv.engr.scu.edu/NQuinn/COEN288/Manifesto.pdf. If you read Kensystems sources in that light, no one needs to search for the literal words "patent" in these sources to reallize that these are examples for a concurrency that hurts. Swen (talk) 16:05, 4 March 2011 (UTC)

 * Ha! That just proves my point that the sourcing is inadequate. Swen reads them and sees an anti-patent message, but the edits in question were pro-patent (since copyright is inadequate). If two people are interpreting something in completely opposite ways, then better sources are clearly required. GDallimore (Talk) 16:50, 4 March 2011 (UTC)

 * Overlapping property rights occur all the time. For instance, both the translator and the original author have a copyright on a translated text. Trademarks may be protected both by copyright and trademark law. Having said that, "software patents" protect the underlying ideas and principles that are not protected by copyright in any jurisdiction.

 * Perhaps a more fundamental observation is that "software patents" is the name of a controversy more than a designation for a type of patents. Given that it is a controversy, non-neutral arguments are unavoidable, and the neutrality of the article is only achieved if the arguments pro and con a reasonably balanced. To start with, the very existence of swpats is questioned. For me, the practical defintion is: a software patent is a patent that passed the art. 52(2c+3) EPC test in Europe, or a patent that has something to do with software that passed the § 101 test in the US (and nobody knows what that test really is, now that the "machine or transformation" test has been rejected by the Supreme Court. — Preceding unsigned comment added by Rbakels (talk • contribs) 13:12, 23 July 2012 (UTC)

Yahoo patents could throw a monkey wrench into Facebook’s IPO hopes
http://venturebeat.com/2011/11/08/yahoo-facebook-patent-dispute/ Ottawahitech (talk) 00:47, 10 November 2011 (UTC)

Barnes & Noble Urges U.S. to Probe Microsoft on Patents
http://www.bloomberg.com/news/2011-11-08/barnes-noble-urges-u-s-regulators-to-probe-microsoft-on-mobile-patents.html

German software patents
There are many more software patent cases in Germany than tin the UK. Presently I do no have the time to write an article myself (and to risk that it will be removed because someone found "original research" or whatever). Rbakels (talk) 12:57, 23 July 2012 (UTC)

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Patent Commons
The hopeless Patent Commons stub needs a home, not necessarily here.–Be..anyone (talk) 03:18, 5 February 2014 (UTC)

Mass peer review, patent bounty
Without a separate article on each of mass peer review and patent bounty, it is going to be very difficult to describe what Peer to Patent means relative to software patents, nor how the risk of software patent ambiguity and applicability is managed by real attorneys.

Do some web searches and you'll realize very quickly that these are very widely used terms and at least need to be redirects to whatever article. Neither term is going away and both are fundamental to modern software patent practice, and not only in the US. — Preceding unsigned comment added by 24.142.57.99 (talk) 21:04, 28 December 2014 (UTC)

"Successfully enforced" in Japan?
In the section on Japan, a purported example is given of a software patent that was successfully enforced. However, the enforcement was overturned on appeal. I would hardly call that a "successful" enforcement! Are there any other examples? Hairy Dude (talk) 23:54, 1 June 2015 (UTC)

External links modified
Hello fellow Wikipedians,

I have just added archive links to 4 one external links on Software patent. Please take a moment to review my edit. If necessary, add after the link to keep me from modifying it. Alternatively, you can add to keep me off the page altogether. I made the following changes:
 * Added archive https://web.archive.org/20090327115425/http://www.europarl.eu.int/meetdocs/committees/itre/20030219/488498en.pdf to http://www.europarl.eu.int/meetdocs/committees/itre/20030219/488498en.pdf
 * Added archive https://web.archive.org/20070621083254/http://www.miplc.de/research/master_theses/2004_2005/abstracts/abstract_laub.pdf to http://www.miplc.de/research/master_theses/2004_2005/abstracts/abstract_laub.pdf
 * Added archive https://web.archive.org/20130604193602/http://swpat.ffii.org/patents/effects to http://swpat.ffii.org/patents/effects
 * Added archive https://web.archive.org/20130115203127/http://www.sun.com/smi/Press/sunflash/2005-01/sunflash.20050125.2.xml to http://www.sun.com/smi/Press/sunflash/2005-01/sunflash.20050125.2.xml

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"The (Relatively) Easy Case for Patents on Inventions" - does not apply to software/method patents?
At Arrow information paradox (should that page and/or this paper and/or the other, be linked from this WP article, maybe in "See also" (or from similar articles and/or the debate-one?)?), I came across:

 * Cornell Law School professor Oskar Liivak has written in a paper for a conference at Stanford University that Arrow's "paper has been one of the foundational theoretical pillars of the incentive based theory of patents as Arrow’s work is thought to rule out a strictly market-based solution."

That paper is this one: "The (Relatively) Easy Case for Patents on Inventions" that says:

"This article shows that, as to a market for technological ideas or information generally, those suspicions are likely correct, yet, the narrative introduced here focuses on something narrower: the voluntary market exchange of inventions. Inventions are special packages of information coupling technological and economic parameters into a modular thing that interfaces with the overall price system. This article shows that a patent system that supports such a market in inventions can be economically justified relatively unambiguously."

I still haven't read much further, just search for software patent, found noting except for software (only really this footnote): "14 See JAMES BOYLE, SHAMANS, SOFTWARE, AND SPLEENS 253 (1996) (describing support for the “current system” as “an article of religious faith”); see also BESSEN & MEURER, supra note 3 at 74(quoting James Boyle as discussing IP policy not on empirical evidence but instead on “faith-based” reasoning)." comp.arch (talk) 17:23, 13 January 2016 (UTC)

Search summary
When searched for in a Wikipedia search bar, the small blurb for this article reads "concept introduced to create an undue monopoly." Unsure where this content can be changed but I think it's clear it should be. 66.175.245.1 (talk) 16:29, 5 June 2018 (UTC)

Patent rights in software governed by copyright worries me
Especially the Apache mpl and gpl licenses now including patent grants to what are essentially only computer software in copyright only Slinkyw (talk) 18:05, 6 December 2021 (UTC)

Armenia
The Armenia paragraph does not make sense to me. I checked the source article, and the paragraph appears to quote the exact wording of the source article. I suspect a translation issue. Scott McNay (talk) 19:39, 8 April 2023 (UTC)

 * Thanks. I have removed the section. This cannot be true. Edcolins (talk) 17:14, 10 April 2023 (UTC)

title: Talk:Software patent


text:
Outer space

Outer space (or simply space) is the expanse that exists beyond Earth's atmosphere and between celestial bodies. It contains ultra-low levels of particle densities, constituting a near-perfect vacuum of predominantly hydrogen and helium plasma, permeated by electromagnetic radiation, cosmic rays, neutrinos, magnetic fields and dust. The baseline temperature of outer space, as set by the background radiation from the Big Bang, is 2.7255 K.

The plasma between galaxies is thought to account for about half of the baryonic (ordinary) matter in the universe, having a number density of less than one hydrogen atom per cubic metre and a kinetic temperature of millions of kelvins. Local concentrations of matter have condensed into stars and galaxies. Intergalactic space takes up most of the volume of the universe, but even galaxies and star systems consist almost entirely of empty space. Most of the remaining mass-energy in the observable universe is made up of an unknown form, dubbed dark matter and dark energy.

Outer space does not begin at a definite altitude above Earth's surface. The Kármán line, an altitude of 100 km above sea level, is conventionally used as the start of outer space in space treaties and for aerospace records keeping. Certain portions of the upper stratosphere and the mesosphere are sometimes referred to as "near space". The framework for international space law was established by the Outer Space Treaty, which entered into force on 10 October 1967. This treaty precludes any claims of national sovereignty and permits all states to freely explore outer space. Despite the drafting of UN resolutions for the peaceful uses of outer space, anti-satellite weapons have been tested in Earth orbit.

The concept that the space between the Earth and the Moon must be a vacuum was first proposed in the 17th century after scientists discovered that air pressure decreased with altitude. The immense scale of outer space was grasped in the 20th century when the distance to the Andromeda galaxy was first measured. Humans began the physical exploration of space later in the same century with the advent of high-altitude balloon flights. This was followed by crewed rocket flights and, then, crewed Earth orbit, first achieved by Yuri Gagarin of the Soviet Union in 1961. The economic cost of putting objects, including humans, into space is very high, limiting human spaceflight to low Earth orbit and the Moon. On the other hand, uncrewed spacecraft have reached all of the known planets in the Solar System. Outer space represents a challenging environment for human exploration because of the hazards of vacuum and radiation. Microgravity has a negative effect on human physiology that causes both muscle atrophy and bone loss.

Terminology
The use of the short version space, as meaning 'the region beyond Earth's sky', predates the use of full term "outer space", with the earliest recorded use of this meaning in an epic poem by John Milton called Paradise Lost, published in 1667.

The term outward space existed in a poem from 1842 by the English poet Lady Emmeline Stuart-Wortley called "The Maiden of Moscow", but in astronomy the term outer space found its application for the first time in 1845 by Alexander von Humboldt. The term was eventually popularized through the writings of H. G. Wells after 1901. Theodore von Kármán used the term of free space to name the space of altitudes above Earth where spacecrafts reach conditions sufficiently free from atmospheric drag, differentiating it from airspace, identifying a legal space above territories free from the sovereign jurisdiction of countries.

"Spaceborne" denotes existing in outer space, especially if carried by a spacecraft; similarly, "space-based" means based in outer space or on a planet or moon.

Formation and state

The size of the whole universe is unknown, and it might be infinite in extent. According to the Big Bang theory, the very early universe was an extremely hot and dense state about 13.8 billion years ago which rapidly expanded. About 380,000 years later the universe had cooled sufficiently to allow protons and electrons to combine and form hydrogen—the so-called recombination epoch. When this happened, matter and energy became decoupled, allowing photons to travel freely through the continually expanding space. Matter that remained following the initial expansion has since undergone gravitational collapse to create stars, galaxies and other astronomical objects, leaving behind a deep vacuum that forms what is now called outer space. As light has a finite velocity, this theory constrains the size of the directly observable universe.

The present day shape of the universe has been determined from measurements of the cosmic microwave background using satellites like the Wilkinson Microwave Anisotropy Probe. These observations indicate that the spatial geometry of the observable universe is "flat", meaning that photons on parallel paths at one point remain parallel as they travel through space to the limit of the observable universe, except for local gravity. The flat universe, combined with the measured mass density of the universe and the accelerating expansion of the universe, indicates that space has a non-zero vacuum energy, which is called dark energy.

Estimates put the average energy density of the present day universe at the equivalent of 5.9 protons per cubic meter, including dark energy, dark matter, and baryonic matter (ordinary matter composed of atoms). The atoms account for only 4.6% of the total energy density, or a density of one proton per four cubic meters. The density of the universe is clearly not uniform; it ranges from relatively high density in galaxies—including very high density in structures within galaxies, such as planets, stars, and black holes—to conditions in vast voids that have much lower density, at least in terms of visible matter. Unlike matter and dark matter, dark energy seems not to be concentrated in galaxies: although dark energy may account for a majority of the mass-energy in the universe, dark energy's influence is 5 orders of magnitude smaller than the influence of gravity from matter and dark matter within the Milky Way.

Environment
Outer space is the closest known approximation to a perfect vacuum. It has effectively no friction, allowing stars, planets, and moons to move freely along their ideal orbits, following the initial formation stage. The deep vacuum of intergalactic space is not devoid of matter, as it contains a few hydrogen atoms per cubic meter. By comparison, the air humans breathe contains about 1025 molecules per cubic meter. The low density of matter in outer space means that electromagnetic radiation can travel great distances without being scattered: the mean free path of a photon in intergalactic space is about 1023 km, or 10 billion light years. In spite of this, extinction, which is the absorption and scattering of photons by dust and gas, is an important factor in galactic and intergalactic astronomy.

Stars, planets, and moons retain their atmospheres by gravitational attraction. Atmospheres have no clearly delineated upper boundary: the density of atmospheric gas gradually decreases with distance from the object until it becomes indistinguishable from outer space. The Earth's atmospheric pressure drops to about 0.032Pa at 100 km of altitude, compared to 100,000 Pa for the International Union of Pure and Applied Chemistry (IUPAC) definition of standard pressure. Above this altitude, isotropic gas pressure rapidly becomes insignificant when compared to radiation pressure from the Sun and the dynamic pressure of the solar wind. The thermosphere in this range has large gradients of pressure, temperature and composition, and varies greatly due to space weather.

The temperature of outer space is measured in terms of the kinetic activity of the gas, as it is on Earth. The radiation of outer space has a different temperature than the kinetic temperature of the gas, meaning that the gas and radiation are not in thermodynamic equilibrium. All of the observable universe is filled with photons that were created during the Big Bang, which is known as the cosmic microwave background radiation (CMB). (There is quite likely a correspondingly large number of neutrinos called the cosmic neutrino background. ) The current black body temperature of the background radiation is about 2.7 K. The gas temperatures in outer space can vary widely. For example, the temperature in the Boomerang Nebula is 1 K, while the solar corona reaches temperatures over 1,200,000 - 2,600,000 K.

Magnetic fields have been detected in the space around just about every class of celestial object. Star formation in spiral galaxies can generate small-scale dynamos, creating turbulent magnetic field strengths of around 5–10 μG. The Davis–Greenstein effect causes elongated dust grains to align themselves with a galaxy's magnetic field, resulting in weak optical polarization. This has been used to show ordered magnetic fields that exist in several nearby galaxies. Magneto-hydrodynamic processes in active elliptical galaxies produce their characteristic jets and radio lobes. Non-thermal radio sources have been detected even among the most distant high-z sources, indicating the presence of magnetic fields.

Outside a protective atmosphere and magnetic field, there are few obstacles to the passage through space of energetic subatomic particles known as cosmic rays. These particles have energies ranging from about 106 eV up to an extreme 1020 eV of ultra-high-energy cosmic rays. The peak flux of cosmic rays occurs at energies of about 109 eV, with approximately 87% protons, 12% helium nuclei and 1% heavier nuclei. In the high energy range, the flux of electrons is only about 1% of that of protons. Cosmic rays can damage electronic components and pose a health threat to space travelers. According to astronauts, like Don Pettit, space has a burned/metallic odor that clings to their suits and equipment, similar to the scent of an arc welding torch.

Effect on biology and human bodies

Despite the harsh environment, several life forms have been found that can withstand extreme space conditions for extended periods. Species of lichen carried on the ESA BIOPAN facility survived exposure for ten days in 2007. Seeds of Arabidopsis thaliana and Nicotiana tabacum germinated after being exposed to space for 1.5 years. A strain of Bacillus subtilis has survived 559 days when exposed to low Earth orbit or a simulated Martian environment. The lithopanspermia hypothesis suggests that rocks ejected into outer space from life-harboring planets may successfully transport life forms to another habitable world. A conjecture is that just such a scenario occurred early in the history of the Solar System, with potentially microorganism-bearing rocks being exchanged between Venus, Earth, and Mars.

Vacuum
The lack of pressure in space is the most immediate dangerous characteristic of space to humans. Pressure decreases above Earth, reaching a level at an altitude of around 19.14 km that matches the vapor pressure of water at the temperature of the human body. This pressure level is called the Armstrong line, named after American physician Harry G. Armstrong. At or above the Armstrong line, fluids in the throat and lungs boil away. More specifically, exposed bodily liquids such as saliva, tears, and liquids in the lungs boil away. Hence, at this altitude, human survival requires a pressure suit, or a pressurized capsule.

Out in space, sudden exposure of an unprotected human to very low pressure, such as during a rapid decompression, can cause pulmonary barotrauma—a rupture of the lungs, due to the large pressure differential between inside and outside the chest. Even if the subject's airway is fully open, the flow of air through the windpipe may be too slow to prevent the rupture. Rapid decompression can rupture eardrums and sinuses, bruising and blood seep can occur in soft tissues, and shock can cause an increase in oxygen consumption that leads to hypoxia.

As a consequence of rapid decompression, oxygen dissolved in the blood empties into the lungs to try to equalize the partial pressure gradient. Once the deoxygenated blood arrives at the brain, humans lose consciousness after a few seconds and die of hypoxia within minutes. Blood and other body fluids boil when the pressure drops below 6.3 kPa, and this condition is called ebullism. The steam may bloat the body to twice its normal size and slow circulation, but tissues are elastic and porous enough to prevent rupture. Ebullism is slowed by the pressure containment of blood vessels, so some blood remains liquid.

Swelling and ebullism can be reduced by containment in a pressure suit. The Crew Altitude Protection Suit (CAPS), a fitted elastic garment designed in the 1960s for astronauts, prevents ebullism at pressures as low as 2 kPa. Supplemental oxygen is needed at 8 km to provide enough oxygen for breathing and to prevent water loss, while above 20 km pressure suits are essential to prevent ebullism. Most space suits use around 30 - 39 kPa of pure oxygen, about the same as the partial pressure of oxygen at the Earth's surface. This pressure is high enough to prevent ebullism, but evaporation of nitrogen dissolved in the blood could still cause decompression sickness and gas embolisms if not managed.

Weightlessness and radiation
Humans evolved for life in Earth gravity, and exposure to weightlessness has been shown to have deleterious effects on human health. Initially, more than 50% of astronauts experience space motion sickness. This can cause nausea and vomiting, vertigo, headaches, lethargy, and overall malaise. The duration of space sickness varies, but it typically lasts for 1–3 days, after which the body adjusts to the new environment. Longer-term exposure to weightlessness results in muscle atrophy and deterioration of the skeleton, or spaceflight osteopenia. These effects can be minimized through a regimen of exercise. Other effects include fluid redistribution, slowing of the cardiovascular system, decreased production of red blood cells, balance disorders, and a weakening of the immune system. Lesser symptoms include loss of body mass, nasal congestion, sleep disturbance, and puffiness of the face.

During long-duration space travel, radiation can pose an acute health hazard. Exposure to high-energy, ionizing cosmic rays can result in fatigue, nausea, vomiting, as well as damage to the immune system and changes to the white blood cell count. Over longer durations, symptoms include an increased risk of cancer, plus damage to the eyes, nervous system, lungs and the gastrointestinal tract. On a round-trip Mars mission lasting three years, a large fraction of the cells in an astronaut's body would be traversed and potentially damaged by high energy nuclei. The energy of such particles is significantly diminished by the shielding provided by the walls of a spacecraft and can be further diminished by water containers and other barriers. The impact of the cosmic rays upon the shielding produces additional radiation that can affect the crew. Further research is needed to assess the radiation hazards and determine suitable countermeasures.

Boundary

The transition between Earth's atmosphere and outer space lacks a well-defined physical boundary, with the air pressure steadily decreasing with altitude until it mixes with the solar wind. Various definitions for a practical boundary have been proposed, ranging from 30 km out to 1600000 km.

High-altitude aircraft, such as high-altitude balloons have reached altitudes above Earth of up to 50 km. Up until 2021, the United States designated people who travel above an altitude of 50 mi as astronauts. Astronaut wings are now only awarded to spacecraft crew members that "demonstrated activities during flight that were essential to public safety, or contributed to human space flight safety."

In 2009, scientists used a Supra-Thermal Ion Imager to measure the direction and speed of ions in the atmosphere. They discovered that 118 km above Earth was the midpoint for charged particles transitioning from the gentle winds of the Earth's atmosphere to the more extreme flows of outer space, which can reach velocities well over 268 m/s.

Spacecraft have entered into a highly elliptical orbit with a perigee as low as 80 to 90 km, surviving for multiple orbits. At an altitude of 120 km, descending spacecraft such as NASA's Space Shuttle begin atmospheric entry (termed the Entry Interface), when atmospheric drag becomes noticeable, thus beginning the process of switching from steering with thrusters to maneuvering with aerodynamic control surfaces.

The Kármán line, established by the Fédération Aéronautique Internationale, and used internationally by the United Nations, is set at an altitude of 100 km as a working definition for the boundary between aeronautics and astronautics. This line is named after Theodore von Kármán, who argued for an altitude where a vehicle would have to travel faster than orbital velocity to derive sufficient aerodynamic lift from the atmosphere to support itself, which he calculated to be at an altitude of about 83.8 km, distinguishing space below as the space of aerodynamics and airspace, and above as the space of astronautics and free space.

There is no internationally recognized legal altitude limit on national airspace, although the Kármán line is the most frequently used for this purpose. Objections have been made to setting this limit too high, as it could inhibit space activities due to concerns about airspace violations. It has been argued for setting no specified singular altitude in international law, instead applying different limits depending on the case, in particular based on the craft and its purpose. Spacecraft have flown over foreign countries as low as 30 km, as in the example of the Space Shuttle.

Legal status
The Outer Space Treaty provides the basic framework for international space law. It covers the legal use of outer space by nation states, and includes in its definition of outer space, the Moon, and other celestial bodies. The treaty states that outer space is free for all nation states to explore and is not subject to claims of national sovereignty, calling outer space the "province of all mankind". This status as a common heritage of mankind has been used, though not without opposition, to enforce the right to access and shared use of outer space for all nations equally, particularly non-spacefaring nations. It prohibits the deployment of nuclear weapons in outer space. The treaty was passed by the United Nations General Assembly in 1963 and signed in 1967 by the Union of Soviet Socialist Republics (USSR), the United States of America (USA), and the United Kingdom (UK). As of 2017, 105 state parties have either ratified or acceded to the treaty. An additional 25 states signed the treaty, without ratifying it.

Since 1958, outer space has been the subject of multiple United Nations resolutions. Of these, more than 50 have been concerning the international co-operation in the peaceful uses of outer space and preventing an arms race in space. Four additional space law treaties have been negotiated and drafted by the UN's Committee on the Peaceful Uses of Outer Space. Still, there remains no legal prohibition against deploying conventional weapons in space, and anti-satellite weapons have been successfully tested by the USA, USSR, China, and in 2019, India. The 1979 Moon Treaty turned the jurisdiction of all heavenly bodies (including the orbits around such bodies) over to the international community. The treaty has not been ratified by any nation that currently practices human spaceflight.

In 1976, eight equatorial states (Ecuador, Colombia, Brazil, The Republic of the Congo, Zaire, Uganda, Kenya, and Indonesia) met in Bogotá, Colombia: with their "Declaration of the First Meeting of Equatorial Countries", or the Bogotá Declaration, they claimed control of the segment of the geosynchronous orbital path corresponding to each country. These claims are not internationally accepted.

An increasing issue of international space law and regulation has been the dangers of the growing number of space debris.

Earth orbit
A spacecraft enters orbit when its centripetal acceleration due to gravity is less than or equal to the centrifugal acceleration due to the horizontal component of its velocity. For a low Earth orbit, this velocity is about 7800 m/s; by contrast, the fastest piloted airplane speed ever achieved (excluding speeds achieved by deorbiting spacecraft) was 2200 m/s in 1967 by the North American X-15.

To achieve an orbit, a spacecraft must travel faster than a sub-orbital spaceflight along an arcing trajectory. The energy required to reach Earth orbital velocity at an altitude of 600 km is about 36 MJ/kg, which is six times the energy needed merely to climb to the corresponding altitude. The escape velocity required to pull free of Earth's gravitational field altogether and move into interplanetary space is about 11200 m/s.

Orbiting spacecraft with a perigee below about 2000 km are subject to drag from the Earth's atmosphere, which decreases the orbital altitude. The rate of orbital decay depends on the satellite's cross-sectional area and mass, as well as variations in the air density of the upper atmosphere. At altitudes above 800 km, orbital lifetime is measured in centuries. Below about 300 km, decay becomes more rapid with lifetimes measured in days. Once a satellite descends to 180 km, it has only hours before it vaporizes in the atmosphere.

Regions near the Earth
Space in proximity to the Earth is physically similar to the remainder of interplanetary space, but is home to a multitude of Earth–orbiting satellites and has been subject to extensive studies. For identification purposes, this volume is divided into overlapping regions of space.

 is the region of space extending from low Earth orbits out to geostationary orbits. This region includes the major orbits for artificial satellites and is the site of most of humanity's space activity. The region has seen high levels of space debris, sometimes dubbed space pollution, threatening any space activity in this region. Some of this debris re-enters Earth's atmosphere periodically. Although it meets the definition of outer space, the atmospheric density inside low-Earth orbital space, the first few hundred kilometers above the Kármán line, is still sufficient to produce significant drag on satellites.

Geospace is a region of space that includes Earth's upper atmosphere and magnetosphere. The Van Allen radiation belts lie within the geospace. The outer boundary of geospace is the magnetopause, which forms an interface between the Earth's magnetosphere and the solar wind. The inner boundary is the ionosphere.

The variable space-weather conditions of geospace are affected by the behavior of the Sun and the solar wind; the subject of geospace is interlinked with heliophysics—the study of the Sun and its impact on the planets of the Solar System. The day-side magnetopause is compressed by solar-wind pressure—the subsolar distance from the center of the Earth is typically 10 Earth radii. On the night side, the solar wind stretches the magnetosphere to form a magnetotail that sometimes extends out to more than 100–200 Earth radii. For roughly four days of each month, the lunar surface is shielded from the solar wind as the Moon passes through the magnetotail.

Geospace is populated by electrically charged particles at very low densities, the motions of which are controlled by the Earth's magnetic field. These plasmas form a medium from which storm-like disturbances powered by the solar wind can drive electrical currents into the Earth's upper atmosphere. Geomagnetic storms can disturb two regions of geospace, the radiation belts and the ionosphere. These storms increase fluxes of energetic electrons that can permanently damage satellite electronics, interfering with shortwave radio communication and GPS location and timing. Magnetic storms can be a hazard to astronauts, even in low Earth orbit. They create aurorae seen at high latitudes in an oval surrounding the geomagnetic poles.

xGeo space is a concept used by the US to refer to space of high Earth orbits, ranging from beyond geosynchronous orbit (GEO) at approximately 35786 km, out to the L2 Earth-Moon Lagrange point at 448900 km. This is located beyond the orbit of the Moon and therefore includes cislunar space. Translunar space is the region of lunar transfer orbits, between the Moon and Earth. Cislunar space is a region outside of Earth that includes lunar orbits, the Moon's orbital space around Earth and the Lagrange points.

The region where a body's gravitational potential remains dominant against gravitational pontentials from other bodies, is the body's sphere of influence or gravity well, mostly described with the Hill sphere model. In the case of Earth this includes all space from the Earth to a distance of roughly 1% of the mean distance from Earth to the Sun, or 1.5 e6km. Beyond Earth's Hill sphere extends along Earth's orbital path its orbital and co-orbital space. This space is co-populated by groups of co-orbital Near-Earth Objects (NEOs), such as horseshoe librators and Earth trojans, with some NEOs at times becoming temporary satellites and quasi-moons to Earth.

Deep space is defined by the United States government as all of outer space which lies further from Earth than a typical low-Earth-orbit, thus assigning the moon to deep-space. Other definitions vary the starting point of deep-space from, "That which lies beyond the orbit of the moon," to "That which lies beyond the farthest reaches of the Solar System itself." The International Telecommunication Union responsible for radio communication, including with satellites, defines the beginning of deep-space as, "That which lies further than 2 e6km from Earth, which is about five times the Moon's orbital distance, but which distance is also far less than the distance between Earth and any adjacent planet.

Interplanetary space

Interplanetary space within the Solar System is the space between the eight planets, the space between the planets and the Sun, as well as that space beyond the orbit of the outermost planet Neptune where the Solar wind remains active. The Solar wind is a continuous stream of charged particles emanating from the Sun which creates a very tenuous atmosphere (the heliosphere) for billions of kilometers into space. This wind has a particle density of 5–10 protons/cm3 and is moving at a velocity of 350 - 400 km/s. Interplanetary space extends out to the heliopause where the influence of the galactic environment starts to dominate over the magnetic field and particle flux from the Sun. The distance and strength of the heliopause varies depending on the activity level of the solar wind. The heliopause in turn deflects away low-energy galactic cosmic rays, with this modulation effect peaking during solar maximum.

The volume of interplanetary space is a nearly total vacuum, with a mean free path of about one astronomical unit at the orbital distance of the Earth. This space is not completely empty, and is sparsely filled with cosmic rays, which include ionized atomic nuclei and various subatomic particles. There is gas, plasma and dust, small meteors, and several dozen types of organic molecules discovered to date by microwave spectroscopy. A cloud of interplanetary dust is visible at night as a faint band called the zodiacal light.

Interplanetary space contains the magnetic field generated by the Sun. There are magnetospheres generated by planets such as Jupiter, Saturn, Mercury and the Earth that have their own magnetic fields. These are shaped by the influence of the solar wind into the approximation of a teardrop shape, with the long tail extending outward behind the planet. These magnetic fields can trap particles from the solar wind and other sources, creating belts of charged particles such as the Van Allen radiation belts. Planets without magnetic fields, such as Mars, have their atmospheres gradually eroded by the solar wind.

Interstellar space

Interstellar space is the physical space outside of the bubbles of plasma known as astrospheres, formed by stellar winds originating from individual stars, or formed by Solar wind emanating from the Sun. It is the space between the stars or stellar systems within a nebula or galaxy. Interstellar space contains an interstellar medium of sparse matter and radiation. The boundary between an astrosphere and interstellar space is known as an astropause. For the Sun, the astrosphere and astropause are called the heliosphere and heliopause.

Approximately 70% of the mass of the interstellar medium consists of lone hydrogen atoms; most of the remainder consists of helium atoms. This is enriched with trace amounts of heavier atoms formed through stellar nucleosynthesis. These atoms are ejected into the interstellar medium by stellar winds or when evolved stars begin to shed their outer envelopes such as during the formation of a planetary nebula. The cataclysmic explosion of a supernova propagates shock waves of stellar ejecta outward, distributing it throughout the interstellar medium, including the heavy elements previously formed within the star's core. The density of matter in the interstellar medium can vary considerably: the average is around 106 particles per m3, but cold molecular clouds can hold 108–1012 per m3.

A number of molecules exist in interstellar space, which can form dust particles as tiny as 0.1 μm. The tally of molecules discovered through radio astronomy is steadily increasing at the rate of about four new species per year. Large regions of higher density matter known as molecular clouds allow chemical reactions to occur, including the formation of organic polyatomic species. Much of this chemistry is driven by collisions. Energetic cosmic rays penetrate the cold, dense clouds and ionize hydrogen and helium, resulting, for example, in the trihydrogen cation. An ionized helium atom can then split relatively abundant carbon monoxide to produce ionized carbon, which in turn can lead to organic chemical reactions.

The local interstellar medium is a region of space within 100 pc of the Sun, which is of interest both for its proximity and for its interaction with the Solar System. This volume nearly coincides with a region of space known as the Local Bubble, which is characterized by a lack of dense, cold clouds. It forms a cavity in the Orion Arm of the Milky Way galaxy, with dense molecular clouds lying along the borders, such as those in the constellations of Ophiuchus and Taurus. (The actual distance to the border of this cavity varies from 60 to 250 pc or more.) This volume contains about 104–105 stars and the local interstellar gas counterbalances the astrospheres that surround these stars, with the volume of each sphere varying depending on the local density of the interstellar medium. The Local Bubble contains dozens of warm interstellar clouds with temperatures of up to 7,000 K and radii of 0.5–5 pc.

When stars are moving at sufficiently high peculiar velocities, their astrospheres can generate bow shocks as they collide with the interstellar medium. For decades it was assumed that the Sun had a bow shock. In 2012, data from Interstellar Boundary Explorer (IBEX) and NASA's Voyager probes showed that the Sun's bow shock does not exist. Instead, these authors argue that a subsonic bow wave defines the transition from the solar wind flow to the interstellar medium. A bow shock is a third boundary characteristic of an astrosphere, laying outside the termination shock and the astropause.

Intergalactic space

Intergalactic space is the physical space between galaxies. Studies of the large-scale distribution of galaxies show that the universe has a foam-like structure, with groups and clusters of galaxies lying along filaments that occupy about a tenth of the total space. The remainder forms cosmic voids that are mostly empty of galaxies. Typically, a void spans a distance of 7–30 megaparsecs.

Surrounding and stretching between galaxies, there is a rarefied plasma that is organized in a galactic filamentary structure. This material is called the intergalactic medium (IGM). The density of these filaments of intergalactic medium is about one atom per cubic meter, which is 5–200 times the average density of the universe after including the cosmic voids. The IGM is inferred to be mostly primordial in composition, with 76% hydrogen by mass, and enriched with higher mass elements from high-velocity galactic outflows.

As gas falls into the intergalactic medium from the voids, it heats up to temperatures of 105 K to 107 K. Hence, collisions between atoms have enough energy to cause the bound electron to escape from the hydrogen nuclei; this is why the IGM is ionized. At these temperatures, it is called the warm–hot intergalactic medium (WHIM). (Although the plasma is very hot by terrestrial standards, 105 K is often called "warm" in astrophysics.) Computer simulations and observations indicate that up to half of the atomic matter in the universe might exist in this warm–hot, rarefied state. When gas falls from the filamentary structures of the WHIM into the galaxy clusters at the intersections of the cosmic filaments, it can heat up even more, reaching temperatures of 108 K and above in the so-called intracluster medium (ICM).

History of discovery
In 350 BCE, Greek philosopher Aristotle suggested that nature abhors a vacuum, a principle that became known as the horror vacui. This concept built upon a 5th-century BCE ontological argument by the Greek philosopher Parmenides, who denied the possible existence of a void in space. Based on this idea that a vacuum could not exist, in the West it was widely held for many centuries that space could not be empty. As late as the 17th century, the French philosopher René Descartes argued that the entirety of space must be filled.

In ancient China, the 2nd-century astronomer Zhang Heng became convinced that space must be infinite, extending well beyond the mechanism that supported the Sun and the stars. The surviving books of the Hsüan Yeh school said that the heavens were boundless, "empty and void of substance". Likewise, the "sun, moon, and the company of stars float in the empty space, moving or standing still".

The Italian scientist Galileo Galilei knew that air had mass and so was subject to gravity. In 1640, he demonstrated that an established force resisted the formation of a vacuum. It would remain for his pupil Evangelista Torricelli to create an apparatus that would produce a partial vacuum in 1643. This experiment resulted in the first mercury barometer and created a scientific sensation in Europe. Torricelli suggested that since air has weight, then air pressure should decrease with altitude. The French mathematician Blaise Pascal proposed an experiment to test this hypothesis. In 1648, his brother-in-law, Florin Périer, repeated the experiment on the Puy de Dôme mountain in central France and found that the column was shorter by three inches. This decrease in pressure was further demonstrated by carrying a half-full balloon up a mountain and watching it gradually expand, then contract upon descent.

In 1650, German scientist Otto von Guericke constructed the first vacuum pump: a device that would further refute the principle of horror vacui. He correctly noted that the atmosphere of the Earth surrounds the planet like a shell, with the density gradually declining with altitude. He concluded that there must be a vacuum between the Earth and the Moon.

In the 15th century, German theologian Nicolaus Cusanus speculated that the universe lacked a center and a circumference. He believed that the universe, while not infinite, could not be held as finite as it lacked any bounds within which it could be contained. These ideas led to speculations as to the infinite dimension of space by the Italian philosopher Giordano Bruno in the 16th century. He extended the Copernican heliocentric cosmology to the concept of an infinite universe filled with a substance he called aether, which did not resist the motion of heavenly bodies. English philosopher William Gilbert arrived at a similar conclusion, arguing that the stars are visible to us only because they are surrounded by a thin aether or a void. This concept of an aether originated with ancient Greek philosophers, including Aristotle, who conceived of it as the medium through which the heavenly bodies move.

The concept of a universe filled with a luminiferous aether retained support among some scientists until the early 20th century. This form of aether was viewed as the medium through which light could propagate. In 1887, the Michelson–Morley experiment tried to detect the Earth's motion through this medium by looking for changes in the speed of light depending on the direction of the planet's motion. The null result indicated something was wrong with the concept. The idea of the luminiferous aether was then abandoned. It was replaced by Albert Einstein's theory of special relativity, which holds that the speed of light in a vacuum is a fixed constant, independent of the observer's motion or frame of reference.

The first professional astronomer to support the concept of an infinite universe was the Englishman Thomas Digges in 1576. But the scale of the universe remained unknown until the first successful measurement of the distance to a nearby star in 1838 by the German astronomer Friedrich Bessel. He showed that the star system 61 Cygni had a parallax of just 0.31 arcseconds (compared to the modern value of 0.287″). This corresponds to a distance of over 10 light years. In 1917, Heber Curtis noted that novae in spiral nebulae were, on average, 10 magnitudes fainter than galactic novae, suggesting that the former are 100 times further away. The distance to the Andromeda Galaxy was determined in 1923 by American astronomer Edwin Hubble by measuring the brightness of cepheid variables in that galaxy, a new technique discovered by Henrietta Leavitt. This established that the Andromeda galaxy, and by extension all galaxies, lay well outside the Milky Way.

The modern concept of outer space is based on the "Big Bang" cosmology, first proposed in 1931 by the Belgian physicist Georges Lemaître. This theory holds that the universe originated from a state of extreme energy density that has since undergone continuous expansion.

The earliest known estimate of the temperature of outer space was by the Swiss physicist Charles É. Guillaume in 1896. Using the estimated radiation of the background stars, he concluded that space must be heated to a temperature of 5–6 K. British physicist Arthur Eddington made a similar calculation to derive a temperature of 3.18 K in 1926. German physicist Erich Regener used the total measured energy of cosmic rays to estimate an intergalactic temperature of 2.8 K in 1933. American physicists Ralph Alpher and Robert Herman predicted 5 K for the temperature of space in 1948, based on the gradual decrease in background energy following the then-new Big Bang theory.

Exploration

For most of human history, space was explored by observations made from the Earth's surface—initially with the unaided eye and then with the telescope. Before reliable rocket technology, the closest that humans had come to reaching outer space was through balloon flights. In 1935, the American Explorer II crewed balloon flight reached an altitude of 22 km. This was greatly exceeded in 1942 when the third launch of the German A-4 rocket climbed to an altitude of about 80 km. In 1957, the uncrewed satellite Sputnik 1 was launched by a Russian R-7 rocket, achieving Earth orbit at an altitude of 215 - 939 km. This was followed by the first human spaceflight in 1961, when Yuri Gagarin was sent into orbit on Vostok 1. The first humans to escape low Earth orbit were Frank Borman, Jim Lovell and William Anders in 1968 on board the American Apollo 8, which achieved lunar orbit and reached a maximum distance of 377349 km from the Earth.

The first spacecraft to reach escape velocity was the Soviet Luna 1, which performed a fly-by of the Moon in 1959. In 1961, Venera 1 became the first planetary probe. It revealed the presence of the solar wind and performed the first fly-by of Venus, although contact was lost before reaching Venus. The first successful planetary mission was the 1962 fly-by of Venus by Mariner 2. The first fly-by of Mars was by Mariner 4 in 1964. Since that time, uncrewed spacecraft have successfully examined each of the Solar System's planets, as well their moons and many minor planets and comets. They remain a fundamental tool for the exploration of outer space, as well as for observation of the Earth. In August 2012, Voyager 1 became the first man-made object to leave the Solar System and enter interstellar space.

Application
Outer space has become an important element of global society. It provides multiple applications that are beneficial to the economy and scientific research.

The placing of artificial satellites in Earth orbit has produced numerous benefits and has become the dominating sector of the space economy. They allow relay of long-range communications like television, provide a means of precise navigation, and permit direct monitoring of weather conditions and remote sensing of the Earth. The latter role serves a variety of purposes, including tracking soil moisture for agriculture, prediction of water outflow from seasonal snow packs, detection of diseases in plants and trees, and surveillance of military activities. They facilitate the discovery and monitoring of climate change influences. Satellites make use of the significantly reduced drag in space to stay in stable orbits, allowing them to efficiently span the whole globe, compared to for example stratospheric balloons or high-altitude platform stations, which have other benefits.

The absence of air makes outer space an ideal location for astronomy at all wavelengths of the electromagnetic spectrum. This is evidenced by the spectacular pictures sent back by the Hubble Space Telescope, allowing light from more than 13 billion years ago—almost to the time of the Big Bang—to be observed. Not every location in space is ideal for a telescope. The interplanetary zodiacal dust emits a diffuse near-infrared radiation that can mask the emission of faint sources such as extrasolar planets. Moving an infrared telescope out past the dust increases its effectiveness. Likewise, a site like the Daedalus crater on the far side of the Moon could shield a radio telescope from the radio frequency interference that hampers Earth-based observations.

The deep vacuum of space could make it an attractive environment for certain industrial processes, such as those requiring ultraclean surfaces. Like asteroid mining, space manufacturing would require a large financial investment with little prospect of immediate return. An important factor in the total expense is the high cost of placing mass into Earth orbit: $–$ per kg, according to a 2006 estimate (allowing for inflation since then). The cost of access to space has declined since 2013. Partially reusable rockets such as the Falcon 9 have lowered access to space below 3500 dollars per kilogram. With these new rockets the cost to send materials into space remains prohibitively high for many industries. Proposed concepts for addressing this issue include, fully reusable launch systems, non-rocket spacelaunch, momentum exchange tethers, and space elevators.

Interstellar travel for a human crew remains at present only a theoretical possibility. The distances to the nearest stars mean it would require new technological developments and the ability to safely sustain crews for journeys lasting several decades. For example, the Daedalus Project study, which proposed a spacecraft powered by the fusion of deuterium and helium-3, would require 36 years to reach the "nearby" Alpha Centauri system. Other proposed interstellar propulsion systems include light sails, ramjets, and beam-powered propulsion. More advanced propulsion systems could use antimatter as a fuel, potentially reaching relativistic velocities.

From the Earth's surface, the ultracold temperature of outer space can be used as a renewable cooling technology for various applications on Earth through passive daytime radiative cooling. This enhances longwave infrared (LWIR) thermal radiation heat transfer through the amosphere's infrared window into outer space, lowering ambient temperatures. Photonic metamaterials can be used to suppress solar heating.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Outer space


text:
J. R. D. Tata

Jehangir Ratanji Dadabhoy Tata (29 July 1904 – 29 November 1993) was an Indian industrialist, philanthropist, aviator and chairman of Tata Group.

Born into the Tata Family of India, he was the son of noted businessman Ratanji Dadabhoy Tata and his wife Suzanne Brière. He is best known for being the founder of several industries under the Tata Group, including Tata Consultancy Services, Tata Motors, Titan Industries, Tata Salt, Voltas and Air India. In 1983, he was awarded the French Legion of Honour and in 1955 and 1992, he received two of India's highest civilian awards: the Padma Vibhushan and the Bharat Ratna. These honours were bestowed on him for his contributions to Indian industry.

Early life
J. R. D. Tata was born on 29 July 1904 to an Indian Parsi family in Paris, France. He was the second child of businessman Ratanji Dadabhoy Tata and his French wife, Suzanne "Sooni" Brière. His father was the first cousin of Jamsetji Tata, a pioneer industrialist in India. He had one elder sister Sylla, a younger sister Rodabeh and two younger brothers Darab and Jamshed (called Jimmy) Tata. His sister, Sylla, was married to Dinshaw Maneckji Petit, the third baronet of Petits. His sister's sister-in-law, Rattanbai Petit, was the wife of Muhammad Ali Jinnah, who later became the founder of Pakistan in August 1947. Jinnah and Rattanbai's daughter Dina Jinnah, was married to Bombay Dyeing chairman Neville Wadia who was the son of Sir Ness Wadia and Lady Eveylne Clara Powell Wadia. Neville and Dina had two children, Nusli Wadia and Diana N Wadia. Nusli is the current chairman of the Wadia Group. Nusli married Maureen Waida and they have two children, Jehangir Wadia and Ness Wadia.

As his mother was French, he spent much of his childhood in France and as a result, French was his first language. He attended the Janson De Sailly School in Paris. One of the teachers at that school used to call him L'Egyptien.

He attended the Cathedral and John Connon School, Bombay. Tata was educated in London, Japan, France and India. When his father joined the Tata company he moved the whole family to London. During this time, J. R. D.'s mother died at the age of 43 while his father was in India and his family was in France.

After his mother's death, Ratanji Dadabhoy Tata decided to move his family to India and sent J. R. D. to England for higher studies in October 1923. He was enrolled in a grammar school, and was interested in studying engineering at Cambridge University. However, as a citizen of France J. R. D. had to enlist in the army for at least a year. In between grammar school and his time in the army, he spent a brief spell at home in Bombay. After joining the French Army he was posted into a regiment of spahis. Upon discovering Tata could not only read and write French and English, but could type as well, a colonel had him assigned as a secretary in his office. After his time in the French Army, his father decided to bring him back to India and he joined the Tata Company.

In 1929, Tata renounced his French citizenship and became an Indian citizen. In 1930 Tata married Thelma Vicaji, the niece of Jack Vicaji, a colourful lawyer whom he hired to defend him on a charge of driving his Bugatti too fast along Bombay's main promenade, Marine Drive. Previously he had been engaged to Dinbai Mehta, the future mother of The Economist editor Shapur Kharegat.

While he was born to a Parsi father, and his French mother converted to Zoroastrianism, J. R. D. was agnostic. He found some Parsi religious customs like their funeral rites and their exclusiveness irksome. He adhered to the three basic tenets of Zoroastrianism, which were good thoughts, good words, and good deeds, but he did not profess belief or disbelief in God.

Career
When Tata was in tour, he was inspired by his friend's father, aviation pioneer Louis Blériot, the first man to fly across the English Channel, and took to flying. On 10 February 1929, Tata obtained the first license issued in India. He later came to be known as the "Father of Indian civil aviation". He founded India's first commercial airline, Tata Airlines in 1932, which became Air India in 1946, now India's national airline. He and Nevill Vintcent worked together in building Tata Airlines. They were also good friends. In 1929, J. R. D. became one of the first Indians to be granted a commercial's license. In 1932 Tata Aviation Service, the forerunner to Tata Airline and Air India, took to the skies. That same year he flew the first commercial mail flight to Juhu, in a de Havilland Puss Moth.

The first flight in the History of Indian aviation lifted off from Drigh in Karachi to Madras with J. R. D. at the controls of a Puss on 15 October 1932. J. R. D. nourished and nurtured his airline baby through to 1953, when the government of Jawaharlal Nehru nationalised Air India. It was a decision J. R. D. had fought against tooth and nail.

He joined Tata Sons as an unpaid apprentice in 1925. In 1938, at the age of 34, Tata was elected Chairman of Tata Sons making him the head of the largest industrial group in India. He took over as Chairman of Tata Sons from his second cousin Nowroji Saklatwala. For decades, he directed the huge Tata Group of companies, with major interests in steel, engineering, power, chemicals and hospitality. He was famous for succeeding in business while maintaining high ethical standards – refusing to bribe politicians or use the black market.

Under his chairmanship, the assets of the Tata Group grew from US$100 million to over US$5 billion. He started with 14 enterprises under his leadership and half a century later on 26 July 1988, when he left, Tata Sons was a conglomerate of 95 enterprises which they either started or in which they had controlling interest.

He was the trustee of the Sir Dorabji Tata Trust from its inception in 1932 for over half a century. Under his guidance, this Trust established Asia's first cancer facility, the Tata Memorial Centre for Cancer, Research and Treatment, Bombay in 1941. He also founded the Tata Institute of Social Sciences (TISS, 1936), the Tata Institute of Fundamental Research (TIFR, 1945), and the National Center for Performing Arts.

In 1945, he founded Tata Motors. In 1948, Tata launched Air India International as India's first international airline. In 1953, the Indian Government appointed Tata as Chairman of Air India and a director on the Board of Indian Airlines – a position he retained for 25 years. For his crowning achievements in aviation, he was bestowed with the title of Honorary Air Commodore of India.

Tata cared greatly for his workers. In 1956, he initiated a programme of closer 'employee association with management' to give workers a stronger voice in the affairs of the company. He firmly believed in employee welfare and espoused the principles of an eight-hour working day, free medical aid, workers' provident scheme, and workmen's accident compensation schemes, which were later, adopted as statutory requirements in India.

He was also a founding member of the first Governing Body of NCAER, the National Council of Applied Economic Research in New Delhi, India's first independent economic policy institute established in 1956. In 1968, he founded Tata Consultancy Services as Tata Computer Centre. In 1979, Tata Steel instituted a new practice: a worker being deemed to be "at work" from the moment he leaves home for work until he returns home from work. This made the company financially liable to the worker for any mishap on the way to and from work. In 1987, he founded Titan Industries. Jamshedpur was also selected as a UN Global Compact City because of the quality of life, conditions of sanitation, roads and welfare that were offered by Tata Steel.

Support of emergency powers in 1975
Tata was also supportive of the declaration of emergency powers by Prime Minister Indira Gandhi, in 1975. He is quoted to have told a reporter of the Times, "things had gone too far. You can't imagine what we've been through here—strikes, boycotts, demonstrations. Why, there were days I couldn't walk out of my house into the streets. The parliamentary system is not suited to our needs."

Awards and honours
Tata received a number of awards. He was conferred the honorary rank of group captain by the Indian Air Force in 1948, was promoted to the Air Commodore rank (equivalent to Brigadier in the army) on 4 October 1966, and was further promoted on 1 April 1974 to the Air Vice Marshal rank. Several international awards for aviation were given to him – the Tony Jannus Award in March 1979, the Gold Air Medal of the Fédération Aéronautique Internationale in 1985, the Edward Warner Award of the International Civil Aviation Organisation, Canada in 1986 and the Daniel Guggenheim Medal in 1988. He received the Padma Vibhushan in 1955. The French Legion of Honour was bestowed on him in 1983. In 1992, because of his selfless humanitarian endeavours, Tata was awarded India's highest civilian honour, the Bharat Ratna. In his memory, the Government of Maharashtra named its first double-decker bridge the Bharatratna JRD Tata Overbridge at Nasik Phata, Pimpri Chinchwad.

Following Prime Minister Indira Gandhi's 1975-1977 Emergency, in which she controversially pursued forced sterilizations as a form of population control, Tata built on these efforts by ordering Tata Steel to open nine family planning centers in 1984. Employees and their non-employee partners were compensated for undergoing sterilization, and factory plant departments were awarded for achieving the lowest fertility rate. While such incentives arguably violated the medical ethics principle of personal bodily autonomy, Tata was awarded the 1992 United Nations Population Award for his efforts.

Death and legacy
Tata died in Geneva, Switzerland of a kidney infection on 29 November 1993, at the age of 89. He said a few days before his death: "Comme c'est doux de mourir" ("How gentle it is to die").

Upon his death, the Indian Parliament was adjourned in his memory, an honour not usually given to persons who are not members of parliament. He was buried at the Père Lachaise Cemetery in Paris.

In 2012, Tata was ranked the sixth "The Greatest Indian" in an Outlook magazine poll, "conducted in conjunction with CNN-IBN and History18 Channels with BBC."

title: J. R. D. Tata


text:
David M. Brown

David McDowell Brown (April 16, 1956 – February 1, 2003) was a United States Navy captain and NASA astronaut. He died on his first spaceflight, when the Space Shuttle Columbia (STS-107) disintegrated during orbital reentry into the Earth's atmosphere. Brown became an astronaut in 1996 but had not served on a space mission prior to the  Columbia disaster. He was posthumously awarded the Congressional Space Medal of Honor.

Education

 * Attended McKinley Elementary, Arlington, Virginia
 * Attended Swanson Middle, Arlington, Virginia
 * 1974: Graduated from Yorktown High School, Arlington, Virginia
 * 1978: Received bachelor of science degree in biology from the College of William and Mary
 * 1982: Received a doctorate in medicine from Eastern Virginia Medical School

Organizations

 * Active in the Boy Scouts of America, where Brown achieved its second-highest rank, Life Scout.
 * Past President, International Association of Military Flight Surgeon Pilots
 * Associate Fellow, Aerospace Medical Association
 * Society of U.S. Naval Flight Surgeons.

Military career
Brown joined the U.S. Navy after his internship at the Medical University of South Carolina. Upon completion of flight surgeon training in 1984, Brown reported to the Navy Branch Hospital in Adak, Alaska, as Director of Medical Services. He was then assigned to Carrier Air Wing Fifteen which deployed aboard the aircraft carrier USS Carl Vinson (CVN-70) in the Western Pacific. In 1988, Brown became the only flight surgeon in a 10-year period to be chosen for pilot training. He was ultimately designated a Naval Aviator in 1990 at NAS Chase Field in Beeville, Texas, ranking number one in his class. Brown was then sent for training and carrier qualification in the A-6E Intruder. In 1991, he reported to the Naval Strike Warfare Center at NAS Fallon, Nevada, serving as a Strike Leader Attack Training Syllabus Instructor and a Contingency Cell Planning Officer. Brown was also qualified in the F/A-18 Hornet and deployed from Japan in 1992 aboard USS Independence (CV-62) flying the A-6E with VA-115. In 1995, he reported to the U.S. Naval Test Pilot School at NAS Patuxent River, Maryland as their flight surgeon, where Brown also flew the T-38 Talon.

Brown logged over 2,700 flight hours with 1,700 in high-performance military aircraft. He was qualified as the first pilot in NASA T-38 aircraft and held a Federal Communications Commission (FCC) issued Technician Class amateur radio license with the call sign KC5ZTC.

NASA career
Selected by NASA in April 1996, Brown reported to the Johnson Space Center in August 1996. He completed two years of training and evaluation and was qualified for flight assignment as a mission specialist. Brown was initially assigned to support payload development for the International Space Station, followed by the astronaut support team responsible for orbiter cockpit setup, crew strap-in, and landing recovery.

On April 21, 2001, Brown appeared on ESPN as an expert on g-force loading on the human body that led to the cancellation of the Firestone Firehawk 600 CART race.

Brown flew aboard Space Shuttle Columbia on STS-107, logging 15 days, 22 hours, and 20 minutes in space from January 16 to February 1, 2003. The flight was a dedicated science and research mission. Working 24 hours a day, in two alternating shifts, the crew successfully conducted approximately 80 experiments. The mission ended abruptly on February 1, 2003, when Columbia's crew perished during entry, 16 minutes before the scheduled landing.

Personal life
The only unmarried member of the STS-107 crew, Brown had previously been romantically involved with NASA engineer Ann Micklos. The couple ended their relationship shortly before the mission and remained close friends until his death. The crew of STS-107 had formed a close friendship during their training, and Brown had been preparing a video to commemorate this once they returned from the mission. He is buried in Arlington National Cemetery.

Awards and honors
Brown, the 1986 recipient of the Navy Operational Flight Surgeon of the Year award, received numerous decorations including:

Qualification insignia

 * Naval Aviator
 * Naval Astronaut
 * Naval Flight Surgeon

Personal decorations

 * Defense Distinguished Service Medal †
 * Meritorious Service Medal
 * Navy and Marine Corps Achievement Medal
 * National Defense Service Medal
 * Congressional Space Medal of Honor †
 * NASA Distinguished Service Medal †
 * NASA Space Flight Medal †

The † symbol indicates a posthumous award.

Tributes

 * Asteroid 51825 Davidbrown was named in honor of Brown.
 * Lunar crater D. Brown is named after Brown.
 * Brown Hall, in the Columbia Village apartments, at the Florida Institute of Technology is named after him.
 * He is the first person ever to be posthumously awarded the William & Mary Alumni Association's, Alumni Medal.
 * The Laurel B. Clark and David M. Brown Aerospace Medicine Academic Center, located at the Naval Aerospace Medical Institute, is named after him.
 * The Captain David Brown Aerospace and Medical Research Endowment was established in his memory to help deserving students attending Eastern Virginia Medical School.
 * The planetarium of Arlington Public Schools was renamed the David M. Brown Planetarium.
 * The Dave Brown Memorial Park in Friendswood, Texas, is named after him.
 * The annual Astronaut Dave Brown Memorial gymnastics meet is held at the College of William & Mary in his honor, where Dave Brown was a gymnast.
 * Yorktown High School Crew Team Men's Varsity 8 boat name Captain David M. Brown - c. 2003
 * Circle Oil Hill Elementary of Circle USD 375 in Kansas grants a scholarship each year - David Brown Hopes & Dreams Scholarship. This scholarship was first awarded in 2005.

title: David M. Brown


text:
Wikipedia:Libel

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title: Wikipedia:Libel


text:
Laurel Clark

Laurel Blair Clark (née Salton; March 10, 1961 – February 1, 2003) was an American NASA astronaut, medical doctor, United States Navy captain, and Space Shuttle mission specialist. She died along with her six fellow crew members in the Space Shuttle Columbia disaster. Clark was posthumously awarded the Congressional Space Medal of Honor.

Early and personal life
Clark was born in Ames, Iowa, but considered Racine, Wisconsin her hometown. Clark was a member of the Gamma Phi Beta sorority at the University of Wisconsin–Madison and held a Federal Communications Commission (FCC) issued Technician Class amateur radio license with the call sign KC5ZSU.

Clark is survived by her husband fellow former U.S. Navy captain and NASA flight surgeon Dr. Jonathan Clark (who was part of an official NASA panel that prepared the final 400-page report about the Space Shuttle Columbia disaster), and son Iain who was born in 1996.

Education

 * 1979: Graduated from William Horlick High School, Racine, Wisconsin
 * 1983: Received Bachelor of Science degree in Zoology from the University of Wisconsin–Madison
 * 1987: Received doctorate in Medicine from the University of Wisconsin–Madison

Organizations
Clark was a member of the Aerospace Medical Association and the Society of U.S. Naval Flight Surgeons. She was also a member of the Olympia Brown Unitarian Universalist Church in Racine, Wisconsin.

Military career
During medical school, Clark did active duty training with the Diving Medicine Department at the United States Navy Experimental Diving Unit in March 1987. After completing medical school, she underwent postgraduate medical education in pediatrics from 1987 to 1988 at the National Naval Medical Center. The following year, Clark completed Navy undersea medical officer training at the Naval Undersea Medical Institute in Groton, Connecticut, and diving medical officer training at the Naval Diving and Salvage Training Center in Panama City, Florida. She was designated a Radiation Health Officer and Undersea Medical Officer. Clark was then assigned as the Submarine Squadron 14 Medical Department Head in Holy Loch, Scotland. During that assignment, she dove with Navy divers and Naval Special Warfare Unit Two SEALs and performed many medical evacuations from US submarines. After two years of operational experience, Clark was designated as a Naval Submarine Medical Officer and Diving Medical Officer.

Clark underwent six months of aeromedical training at the Naval Aerospace Medical Institute at NAS Pensacola in Pensacola, Florida, and was designated as a Naval Flight Surgeon. She was stationed at MCAS Yuma, Arizona, and assigned as Flight Surgeon Marine Attack Squadron 211 (VMA-211), a Marine Corps AV-8B Harrier squadron. Clark made several deployments, including one overseas to the Western Pacific, practiced medicine in austere environments, and flew on multiple aircraft. Her squadron won the Marine Attack Squadron of the Year award for its successful deployment. Clark was then assigned as the Group Flight Surgeon for Marine Aircraft Group 13 (MAG-13).

Before her selection as an astronaut candidate, Clark served as a Flight Surgeon for Training Squadron 86 (VT-86), the Naval Flight Officer advanced training squadron for tactical jets at NAS Pensacola. She was Board Certified by the National Board of Medical Examiners and held a Wisconsin Medical License, and her military qualifications included Radiation Health Officer, Undersea Medical Officer, Diving Medical Officer, Submarine Medical Officer, and Naval Flight Surgeon. Clark was also a Basic Life Support Instructor, Advanced Cardiac Life Support Provider, Advanced Trauma Life Support Provider, and Hyperbaric Chamber Advisor.

NASA career
Selected by NASA in April 1996, Clark reported to the Johnson Space Center in Houston, Texas, in August 1996. After completing two years of training and evaluation, she was qualified for flight assignment as a mission specialist. From July 1997 to August 2000, Clark worked in the Astronaut Office Payloads/Habitability Branch. She flew aboard STS-107, logging 15 days, 22 hours and 21 minutes in space.

Space flight experience

STS-107 Columbia – The 16-day flight was a dedicated science and research mission. Working 24 hours a day, in two alternating shifts, the crew successfully conducted approximately 80 experiments. Clark's bioscience experiments included gardening in space, as she discussed only days before her death in an interview with Milwaukee media near her Wisconsin hometown. The STS-107 mission ended abruptly on February 1, 2003, when Columbia disintegrated and her crew perished during re-entry, 16 minutes before scheduled landing.

Clark also recorded inside the cockpit during Columbia's descent into the Earth's atmosphere on a small digital camera.

Clark's final message to her friends and family was through an email sent from Columbia. In the released text of the email, Clark called the planet magnificent, and explained that while she spends much of the time working back in Spacehab and away from the sights of Earth, "whenever I do get to look out, it is glorious." Clark found that taking photos of the Earth was challenging, "Keeping my fingers crossed that they're in sharp focus." Clark also shared some of the intriguing effects of micro gravity on human physiology, such as constant challenge to stay adequately hydrated due to an "almost non-existent" sense of thirst.

Awards and decorations
Clark was awarded numerous insignia and personal decorations including:

Qualification insignia

 * Naval Astronaut/Flight Surgeon
 * Naval Flight Surgeon
 * Diving Medical Officer
 * Submarine Medical Officer

Personal decorations

 * Defense Distinguished Service Medal †
 * Navy and Marine Corps Commendation Medal with 2 gold award stars (3 awards)
 * Congressional Space Medal of Honor †
 * NASA Distinguished Service Medal †
 * NASA Space Flight Medal †
 * National Defense Service Medal
 * Overseas Service Ribbon

The † symbol indicates a posthumous award.

Tributes

 * Asteroid 51827 Laurelclark was named for Clark.
 * Clark Hill in the Columbia Hills on Mars was named for Clark.
 * L. Clark, an interior crater of the lunar crater Apollo, was named for Clark.
 * Clark Hall, in the Columbia Village Suites at the Florida Institute of Technology, is named after her. The apartments were initially planned to be named the Crane Creek Suites, but were renamed in 2008 to commemorate the Columbia crew.
 * The Laurel Salton Clark Memorial Fountain in Racine, Wisconsin is named for her.
 * In 2004, the Naval Aerospace Medicine Institute named its Aerospace Medicine Academic Center in Pensacola after Clark and David M. Brown
 * Clark Auditorium at Walter Reed National Military Medical Center, Bethesda, Maryland is named for her and displays uniforms, training manuals, and personal items that belonged to her.
 * The Scottish band Runrig pays tribute to Clark on the 2016 album The Story. The final track, "Somewhere", ends with a recording of her voice. Clark was a Runrig fan and had a wake up call with Runrig's "Running to the Light". She took their 2001 The Stamping Ground CD into space with her. When the shuttle disintegrated the CD was found back on Earth, and was presented to the band by her family.
 * Northrop Grumman named a Cygnus cargo spacecraft S.S. Laurel Clark.

title: Laurel Clark