Krypton (comics)

Krypton is a fictional planet in the DC Universe and the native world of Superman. In some stories, it is also the native world of Supergirl, Krypto the Superdog, and Power Girl (in her case, an alternate-universe version designated "Krypton-Two"). Krypton has been consistently described as having been destroyed just after Superman's flight from the planet, though the exact details of its destruction vary by time period, writers, and franchise. Kryptonians were the dominant species on Krypton.

The planet was created by Jerry Siegel and Joe Shuster, and was first referred to in Action Comics #1 (June 1938). The planet made its first full appearance in Superman #1 (Summer 1939).

Overview

Krypton is usually portrayed in comics as having exploded as a result of a nuclear chain reaction caused by the planet's unstable radioactive core (which created Kryptonite, which is deadly to Superman). As originally depicted, all the civilizations and races of Krypton perished in the explosion, with one exception: the baby Kal-El who was placed in an escape rocket by his father, Jor-El, and sent to the planet Earth, where he grew up to become Superman.

Krypton (disambiguation)

Krypton is a chemical element.

Krypton may also refer to:

Crypton may refer to:

See also

Krypton-85

Krypton 85 (⁸⁵Kr) is a radioisotope of krypton.

It has a half-life of 10.756 years and a maximum decay energy of 687 keV. It decays into stable, non-radioactive rubidium-85. Its most common decay (99.57%) is by beta particle emission with maximum energy of 687 keV and an average energy of 251 keV. The second most common decay (0.43%) is by beta particle emission (maximum energy of 173 keV) followed by gamma ray emission (energy of 514 keV).

Other decay modes have very small probabilities and emit less energetic gammas. There are 33 other known isotopes of krypton.

In terms of radiotoxicity, 440 Bq of Kr-85 is equivalent to 1 Bq of radon-222, without considering the rest of the radon decay chain.

Krypton-85 is produced in small quantities by the interaction of cosmic rays with stable krypton-84 in the atmosphere. Natural sources maintain an equilibrium inventory of about 0.09 PBq in the atmosphere.

Isotopes of krypton

There are 33 known isotopes of krypton (Kr) with atomic mass numbers from 69 through 101. Naturally occurring krypton is made of six stable isotopes, two of which might theoretically be slightly radioactive, plus traces of radioisotopes that are produced by cosmic rays in the atmosphere.

The spectral signature of krypton can be observed to have several very sharp lines. When krypton is placed into an electric discharge tube, it emits visible light with a distinctive orange-red color.

Krypton-86 was formerly used to define the meter from 1960 until 1983, when the definition of the meter was the wavelength of the 605 nm (orange) spectral line of a krypton-86 atom.

Radioactive krypton-81 is the product of reactions with cosmic rays that strike the atmosphere, along with some of the other isotopes of krypton. Krypton-81 has a half-life of about 229,000 years.

Krypton-81 has been used for dating old (50,000- to 800,000-year-old) groundwater.

Krypton-85 is a radioisotope of krypton that has a half-life of about 10.75 years. This isotope is produced by the nuclear fission of uranium and plutonium in nuclear weapons testing and in nuclear reactors, as well as by cosmic rays. An important goal of the Limited Nuclear Test Ban Treaty of 1963 was to eliminate the release of such radioisotopes into the atmosphere, and since 1963 much of that krypton-85 has had time to decay. However, it is inevitable that krypton-85 is released during the reprocessing of fuel rods from nuclear reactors.

Planet Mu

Planet Mu is an English electronic music record label run by Mike Paradinas (also known as µ-Ziq). It was based in Worcester until March 2007, then moved to London and has recently relocated to Broadstairs, Kent. The label started out as a subsidiary of Virgin Records, until in 1998 Mike Paradinas set up the label independent of Virgin and was distributed through SRD.

Artists

Planets in astrology

Planets in astrology have a meaning different from the modern astronomical understanding of what a planet is. Before the age of telescopes, the night sky was thought to consist of two very similar components: fixed stars, which remained motionless in relation to each other, and "wandering stars" (Ancient Greek: ἀστέρες πλανῆται asteres planetai), which moved relative to the fixed stars over the course of the year.

To the Greeks and the other earliest astronomers, this group comprised the five planets visible to the naked eye, and excluded the Earth. Although strictly the term "planet" applied only to those five objects, the term was latterly broadened, particularly in the Middle Ages, to include the Sun and the Moon (sometimes referred to as "Lights"), making a total of seven planets. Astrologers retain this definition today.

To ancient astrologers, the planets represented the will of the gods and their direct influence upon human affairs. To modern astrologers the planets represent basic drives or urges in the unconscious, or energy flow regulators representing dimensions of experience. They express themselves with different qualities in the twelve signs of the zodiac and in the twelve houses. The planets are also related to each other in the form of aspects.

Planet (magazine)

Planet is a quarterly cultural and political magazine that looks at Wales from an international perspective, and at the world from the standpoint of Wales.

The magazine publishes high-quality writing, artwork and photography by established and emerging figures, and covers subjects across politics, the arts, literature, current events, social justice questions, minority language and culture, the environment and more.

Planet enjoys a vibrant and diverse international readership and is read by key figures in the Welsh political cultural scene.

The magazine was originally set up as a bi-monthly publication by Ned Thomas in 1970, and was published continually until 1979. This followed a decision in 1967 to devolve the function of The Arts Council of Great Britain in Wales to the Welsh Arts Council. Thomas explained that "The arts council's literature director, Meic Stephens, had a vision of creating a publishing base in Wales that hadn't existed before". The magazine was renamed Planet: the Welsh Internationalist in 1977.