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Dragon C2+
SpaceX COTS Demo Flight 2 (COTS 2), also known as Dragon C2+, was the second test-flight for SpaceX's uncrewed Cargo Dragon spacecraft, launched on the third flight of the company's two-stage Falcon 9 launch vehicle. The flight was performed under a funded agreement from NASA as the second Dragon demonstration mission in the Commercial Orbital Transportation Services (COTS) program. The purpose of the COTS program is to develop and demonstrate commercial sources for cargo re-supply of the International Space Station (ISS). The Dragon C2+ spacecraft was the first American vehicle to visit the ISS since the end of the Space Shuttle program. It was also the first commercial spacecraft to rendezvous and berth with another spacecraft. Initially, the objectives of the C2+ mission were to have been accomplished by two separate missions; Dragon C2 would have carried out a fly-by of the ISS, practiced rendezvous maneuvers and communications with the station, before returning to Earth. A second mission, Dragon C3, would have been the first mission to berth with the station. In July 2011, NASA gave tentative approval to combine the objectives of the two missions. In December 2011, NASA formally approved the merger of the COTS 2 and 3 missions into the Dragon C2+ flight. There were several launch delays, the last one occurring on 19 May 2012, due to a launch abort during the last second before liftoff. Dragon C2+ successfully launched from Cape Canaveral on 22 May 2012. During the mission's first three days all of the COTS 2 objectives were successfully completed. The mission's COTS 3 phase began on 25 May when Dragon rendezvoused again with the ISS and then was successfully captured using the Canadarm2. It was berthed to the station later that day, using the robotic arm. Dragon stayed for almost six days during which the astronauts unloaded cargo, and then reloaded Dragon with Earth-bound cargo. On 31 May, Dragon unberthed from the ISS, its capsule landed in the Pacific Ocean off the California coast and was recovered. All the objectives of the mission were successfully completed, and the Falcon 9-Dragon system became certified to start regular cargo delivery missions to the ISS under the Commercial Resupply Services program.
  • 2.3K
  • 04 Nov 2022
Topic Review
Western European Colonialism and Colonization
File:SierraLeoneHofstra3.1.tiff European colonialism and colonization was the policy or practice of acquiring full or partial political control over other societies and territories, creating a colony, occupying it with settlers, and exploiting it economically. Research suggests, the current conditions of postcolonial countries have roots in colonial actions and policies. For example, colonial policies, such as the type of rule implemented, the nature of investments, and identity of the colonizers, are cited as impacting postcolonial states. Examination of the state-building process, economic development, and cultural norms and mores shows the direct and indirect consequences of colonialism on the postcolonial states.
  • 5.0K
  • 04 Nov 2022
Topic Review
Strain
In chemistry, a molecule experiences strain when its chemical structure undergoes some stress which raises its internal energy in comparison to a strain-free reference compound. The internal energy of a molecule consists of all the energy stored within it. A strained molecule has an additional amount of internal energy which an unstrained molecule does not. This extra internal energy, or strain energy, can be likened to a compressed spring. Much like a compressed spring must be held in place to prevent release of its potential energy, a molecule can be held in an energetically unfavorable conformation by the bonds within that molecule. Without the bonds holding the conformation in place, the strain energy would be released.
  • 4.8K
  • 04 Nov 2022
Topic Review
Sheela Na Gig
Sheela na gigs are figurative carvings of naked women displaying an exaggerated vulva. They are architectural grotesques found all over Europe on churches, castles, and other buildings. The highest concentrations can be found in Ireland, Great Britain, France and Spain, sometimes together with male figures. Ireland has the greatest number of surviving sheela na gig carvings; McMahon and Roberts cite 101 examples in Ireland and 45 examples in Britain. One of the best examples may be found in the Round Tower at Rattoo, in County Kerry, Ireland. There is a replica of the Round Tower sheela na gig in the County Museum in Tralee town. Another well-known example may be seen at Kilpeck in Herefordshire, England. The carvings may have been used to ward off death and evil. Other grotesques, such as gargoyles and hunky punks, were frequently part of church decorations all over Europe. It is commonly said that their purpose was to keep evil spirits away (see apotropaic magic). They often are positioned over doors or windows, presumably to protect these openings.
  • 2.4K
  • 04 Nov 2022
Topic Review
Unilalianism
Unilalianism (/junɨˈleɪ.li.ən.ɪzəm/) is an satirical internet-based art and aesthetic movement, social theory, speculative philosophy, and countercultural thread of post-conceptualism pioneered by tens of indigenous artists who claim to be guided by one central motivation – the deconstruction of the object as an organizing principle of perception. It refers to both a particular subcultural network of performance and multimedia creatives, practicing primarily in one neighborhood within Washington state, as well an ontological reorientation towards decolonization rooted in semiotics, Debordian logic, linguistic theory a la Julia Kristeva's signifiance, theatre, and most generally, gnosticism. Unilalian works of satire often involve adaptations of the Letterist technique of détournement in tandem with demonstrations of psychogeography, typically expressed as deliberate interactions with the public milieu that appeal to themes consistent with unitary urbanism, culture jamming, and durative displays reminiscent of the Situationist Internationale and the Cacophony Society. Unilalianism's etymology is related to Charles Richet's 1905 coinage of xenolalia, the linguistic phenomenon of echolalia, and the religious preoccupation and putative observation of glossolalia. In the case of all three, speech and language lie at the center of attention, providing insight into the direction of Unilalian inquiry.
  • 1.7K
  • 04 Nov 2022
Topic Review
Postcrossing
Postcrossing is an online project that allows its members to send and receive postcards from all over the world. The project's tag line is "send a postcard and receive a postcard back from a random person somewhere in the world!” Its members, also known as postcrossers, send postcards to other members and receive postcards back from other random postcrossers. Where the postcards come from is always a surprise. Postcrossing is the union of the words "postcard" and "crossing" and its origin "is loosely based on the Bookcrossing site". However, the "crossing" or exchange of postcards works in a different way. A member sends a postcard to another postcrosser and receives a postcard back from a random postcrosser. Exchanges between the same two members only occur once; although direct swaps between members happen, they are not part of the official happenings on the site. The project is completely free and anyone with an address can create an account. The postcards and postage fees to mail them are the responsibility of each user. By February 2018 Postcrossing had more than 719,000 members in 212 countries who had registered and exchanged over 45 million postcards that traveled over 229 billion kilometers. The highest concentration of Postcrossing members reside (in order) in Russia, Taiwan, China, the United States, Germany, the Netherlands, Poland, Belarus, Ukraine, Finland and the Czech Republic, each with over 20,000 members. Globally, most postcrossers reside in North America, Europe and East Asia. Of particular note, Postcrossing is popular in eastern European and former-Soviet states. As of January 2012, more than a quarter of the combined total of postcards were sent from Finland, Russia, Estonia, Latvia, Lithuania, Belarus and Ukraine.
  • 1.8K
  • 04 Nov 2022
Topic Review
Wegman Report
The Wegman Report (officially called the Ad Hoc Committee Report on the 'Hockey Stick' Global Climate Reconstruction) was prepared in 2006 by three statisticians led by Edward Wegman at the request of Rep. Joe Barton of the United States House Committee on Energy and Commerce to validate criticisms made by Stephen McIntyre and Ross McKitrick of reconstructions of the temperature record of the past 1000 years, in particular the reconstructions by Mann, Bradley and Hughes which had become the focus of the hockey stick controversy.
  • 1.8K
  • 08 Nov 2022
Topic Review
The Hook
The Hook, or The Hookman, is an urban legend about a killer with a pirate-like hook for a hand attacking a couple in a parked car. The story is thought to date from at least the mid-1950s, and gained significant attention when it was reprinted in the advice column Dear Abby in 1960. It has since become a morality archetype in popular culture, and has been referenced in various horror films.
  • 11.5K
  • 03 Mar 2023
Topic Review
Mozilla Public License
The Mozilla Public License (MPL) is a free and open-source weak copyleft license for most Mozilla Foundation software such as Firefox and Thunderbird The MPL license is developed and maintained by Mozilla, which seeks to balance the concerns of both open-source and proprietary developers; it is distinguished from others as a middle ground between the permissive software BSD-style licenses and the General Public License. So under the terms of the MPL, it allows the integration of MPL-licensed code into proprietary codebases, but only on condition those components remain accessible. MPL has been used by others, such as Adobe to license their Flex product line, and The Document Foundation to license LibreOffice 4.0 (also on LGPL 3+). Version 1.1 was adapted by several projects to form derivative licenses like Sun Microsystems' Common Development and Distribution License. It has undergone two revisions: the minor update 1.1, and a major update version 2.0 nearing the goals of greater simplicity and better compatibility with other licenses.
  • 4.8K
  • 04 Nov 2022
Topic Review
Stewart's Wilt
Stewart's wilt is a serious bacterial disease of corn caused by the bacterium Pantoea stewartii. This bacterium affects plants, particularly types of maize such as sweet, flint, dent, flower, and popcorn. The disease is also known as bacterial wilt or bacterial leaf blight and has shown to be quite problematic in sweet corn. The disease is endemic in the mid-Atlantic and Ohio River Valley regions and in the southern portion of the Corn Belt.
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  • 04 Nov 2022
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