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Alfred Korzybski | Further reading | Further reading
Kodish, Bruce. 2011. Korzybski: A Biography. Pasadena, CA: Extensional Publishing. softcover, 978-09700664-28 hardcover.
Kodish, Bruce and Susan Presby Kodish. 2011. Drive Yourself Sane: Using the Uncommon Sense of General Semantics, Third Edition. Pasadena, CA: Extensional Publishing.
Alfred Korzy... |
Alfred Korzybski | External links | External links
Alfred Korzybski and Gestalt Therapy Website
Australian General Semantics Society
Institute of General Semantics
Finding aid to Alfred Korzybski papers at Columbia University. Rare Book & Manuscript Library.
Category:1879 births
Category:1950 deaths
Category:Writers from Warsaw
Category:Clan Ab... |
Alfred Korzybski | Table of Content | Short description, Early life and career, General semantics, "To be", Anecdotes, Influence, Publications, See also, References, Further reading, External links |
Asteroids (video game) | Short description | Asteroids is a multidirectional shooter video game developed and published by Atari for arcades. It was designed by Lyle Rains and Ed Logg. The player controls a single spaceship in an asteroid field which is periodically traversed by flying saucers. The object of the game is to shoot and destroy the asteroids and sauc... |
Asteroids (video game) | Gameplay | Gameplay
thumb|left|A ship is surrounded by asteroids and a saucer.
The objective of Asteroids is to destroy asteroids and saucers. The player controls a triangular ship that can rotate left and right, fire shots straight forward, and thrust forward. Once the ship begins moving in a direction, it will continue in that ... |
Asteroids (video game) | Lurking exploit | Lurking exploit
In the original game design, saucers were supposed to begin shooting as soon as they appeared, but this was changed. Additionally, saucers can only aim at the player's ship on-screen; they are not capable of aiming across a screen boundary. These behaviors allow a "lurking" strategy, in which the playe... |
Asteroids (video game) | Development | Development
Asteroids was conceived by Lyle Rains and programmed by Ed Logg with collaborations from other Atari staff. Logg was impressed with the Atari Video Computer System (later called the Atari 2600), and he joined Atari's coin-op division to work on Dirt Bike, which was never released due to an unsuccessful fiel... |
Asteroids (video game) | Hardware | Hardware
Asteroids was implemented on hardware developed by Allen and is a vector game, in which the graphics are composed of lines drawn on a vector monitor. Rains initially wanted the game done in raster graphics, but Logg, experienced in vector graphics, suggested an XY monitor because the high image quality would p... |
Asteroids (video game) | Implementation | Implementation
Logg modeled the player's ship, the five-button control scheme, and the game physics after Spacewar!, which he had played as a student at the University of California, Berkeley, but made several changes to improve playability. The ship was programmed into the hardware and rendered by the monitor, and it ... |
Asteroids (video game) | Quirks | Quirks
Asteroids slows down as the player gains 50–100 lives, because there is no limit to the number of lives displayed. The game's code continues trying to draw them even if they fall outside the boundaries of the screen. After more than 250 lives are collected, the game slows down enough that the watchdog timer thin... |
Asteroids (video game) | Ports | Ports
Asteroids was released for the Atari VCS (later renamed Atari 2600) and Atari 8-bit computers in 1981. Programmers Brad Stewart and Bob Smith were unable to fit the Atari VCS port into a 4 KB cartridge. It became the first game for the console to use bank switching, a technique that increases ROM size from 4 KB t... |
Asteroids (video game) | Reception | Reception
Asteroids was immediately successful upon release. It displaced Space Invaders by popularity in the United States and became Atari's best selling arcade game of all time, with over 70,000 units sold. Atari earned an estimated $150 million in sales from the game, and arcade operators earned a further $500 mill... |
Asteroids (video game) | Legacy | Legacy |
Asteroids (video game) | Arcade sequels | Arcade sequels
Released in 1981, Asteroids Deluxe was the first sequel to Asteroids. Dave Shepperd edited the code and made enhancements to the game without Logg's involvement. The onscreen objects are tinted blue, and hyperspace is replaced by a shield that depletes when used. The asteroids rotate, and new "killer sat... |
Asteroids (video game) | Re-releases | Re-releases
The game is half of the Atari Lynx pairing Super Asteroids & Missile Command and included in the 1993 Microsoft Arcade compilation.
Activision published an enhanced version of Asteroids for the PlayStation (1998), Nintendo 64 (1999), Microsoft Windows (1998), Game Boy Color (1999), and Mac (2000). The Ata... |
Asteroids (video game) | Clones | Clones
Quality Software's Asteroids in Space (1980) was one of the best selling games for the Apple II and voted one of the most popular software titles of 1978–80 by Softalk magazine. In December 1981, Byte reviewed eight Asteroids clones for home computers. Three clones for the Apple II were reviewed together in the ... |
Asteroids (video game) | Proposed film adaptation | Proposed film adaptation
In July 2009, Universal Pictures offered Roland Emmerich the option to direct the film adaptation of Asteroids, with Matt Lopez writing the script and Lorenzo di Bonaventura producing the film adaptation. Lopez and di Bonaventura were still attached to write and produce the film adaptation, res... |
Asteroids (video game) | In other media | In other media
The game has made cameo appearances in a number of films and music videos. An Asteroids machine appears in the music video for 38 Special's song Caught Up in You, and one is also briefly seen in the movie Pee-Wee's Big Adventure. |
Asteroids (video game) | World records | World records
On February 6, 1982, Leo Daniels of Carolina Beach, North Carolina, set a world record score of 40,101,910 points. On November 13 of the same year, 15-year-old Scott Safran of Cherry Hill, New Jersey, set a new record at 41,336,440 points. In 1998, to congratulate Safran on his accomplishment, the Twin Ga... |
Asteroids (video game) | References | References |
Asteroids (video game) | External links | External links
at Atari
Category:1979 video games
Category:Arcade video games
Category:Atari 2600 games
Category:Atari 7800 games
Category:Atari 8-bit computer games
Category:Atari arcade games
Category:Atari Lynx games
Category:Cancelled Atari 5200 games
Category:Cancelled Atari Jaguar games
Category:Ed ... |
Asteroids (video game) | Table of Content | Short description, Gameplay, Lurking exploit, Development, Hardware, Implementation, Quirks, Ports, Reception, Legacy, Arcade sequels, Re-releases, Clones, Proposed film adaptation, In other media, World records, References, External links |
Asparagales | Short description | Asparagales (asparagoid lilies) are a diverse order of flowering plants in the monocots. Under the APG IV system of flowering plant classification, Asparagales are the largest order of monocots with 14 families, 1,122 genera, and about 36,000 species, with members as varied as asparagus, orchids, yuccas, irises, onions... |
Asparagales | Description | Description
thumb | Seeds of Hippeastrum with dark phytomelan-containing coat
thumb | Tree-like habit created by secondary thickening in Beaucarnea recurvata
Although most species in the order are herbaceous, some no more than 15 cm high, there are a number of climbers (e.g., some species of Asparagus), as well as sev... |
Asparagales | Taxonomy | Taxonomy
As circumscribed within the Angiosperm Phylogeny Group system Asparagales is the largest order within the monocotyledons, with 14 families, 1,122 genera and about 25,000–42,000 species, thus accounting for about 50% of all monocots and 10–15% of the flowering plants (angiosperms). The attribution of botanical... |
Asparagales | History | History |
Asparagales | Pre-Darwinian | Pre-Darwinian
The type genus, Asparagus, from which the name of the order is derived, was described by Carl Linnaeus in 1753, with ten species. He placed Asparagus within the Hexandria Monogynia (six stamens, one carpel) in his sexual classification in the Species Plantarum. The majority of taxa now considered to con... |
Asparagales | Post-Darwinian | Post-Darwinian
The appearance of Charles Darwin's Origin of Species in 1859 changed the way that taxonomists considered plant classification, incorporating evolutionary information into their schemata. The Darwinian approach led to the concept of phylogeny (tree-like structure) in assembling classification systems, s... |
Asparagales | Twentieth century | Twentieth century
thumb|Longitudinal section of Narcissus poeticus, R Wettstein Handbuch der Systematischen Botanik 1901–1924In the twentieth century the Wettstein system (1901–1935) placed many of the taxa in an order called 'Liliiflorae'. Next Johannes Paulus Lotsy (1911) proposed dividing the Liliiflorae into a nu... |
Asparagales | Phylogenetics | Phylogenetics
The order Asparagales as currently circumscribed has only recently been recognized in classification systems, through the advent of phylogenetics. The 1990s saw considerable progress in plant phylogeny and phylogenetic theory, enabling a phylogenetic tree to be constructed for all of the flowering plan... |
Asparagales | Phylogeny and APG system | Phylogeny and APG system
The 2009 revision of the Angiosperm Phylogeny Group system, APG III, places the order in the clade monocots.
From the Dahlgren system of 1985 onwards, studies based mainly on morphology had identified the Asparagales as a distinct group, but had also included groups now located in Liliales, Pa... |
Asparagales | Subdivision | Subdivision
A phylogenetic tree for the Asparagales, generally to family level, but including groups which were recently and widely treated as families but which are now reduced to subfamily rank, is shown below.
The tree shown above can be divided into a basal paraphyletic group, the 'lower Asparagales (asparagoids... |
Asparagales | Changes to family structure in APG III | Changes to family structure in APG III
The APG III system when it was published in 2009, greatly expanded the families Xanthorrhoeaceae, Amaryllidaceae, and Asparagaceae. Thirteen of the families of the earlier APG II system were thereby reduced to subfamilies within these three families. The expanded Xanthorrhoeacea... |
Asparagales | Structure of Asparagales | Structure of Asparagales |
Asparagales | Orchid clade | Orchid clade
Orchidaceae is possibly the largest family of all angiosperms (only Asteraceae might – or might not – be more speciose) and hence by far the largest in the order. The Dahlgren system recognized three families of orchids, but DNA sequence analysis later showed that these families are polyphyletic and so sho... |
Asparagales | Boryaceae to Hypoxidaceae | Boryaceae to Hypoxidaceae
The four families excluding Boryaceae form a well-supported clade in studies based on DNA sequence analysis. All four contain relatively few species, and it has been suggested that they be combined into one family under the name Hypoxidaceae sensu lato. The relationship between Boryaceae (whic... |
Asparagales | Ixioliriaceae to Xeronemataceae | Ixioliriaceae to Xeronemataceae
The relationship shown between Ixioliriaceae and Tecophilaeaceae is still unclear. Some studies have supported a clade of these two families, others have not. The position of Doryanthaceae has also varied, with support for the position shown above, but also support for other positions.
... |
Asparagales | Asphodelaceae + 'core Asparagales' | Asphodelaceae + 'core Asparagales'
The next node in the tree (Xanthorrhoeaceae sensu lato + the 'core Asparagales') has strong support. 'Anomalous' secondary thickening occurs among this clade, e.g. in Xanthorrhoea (family Asphodelaceae) and Dracaena (family Asparagaceae sensu lato), with species reaching tree-like pro... |
Asparagales | Evolution | Evolution
Several studies have attempted to date the evolution of the Asparagales, based on phylogenetic evidence. Earlier studies generally give younger dates than more recent studies, which have been preferred in the table below.
+ Approx. date inMillions of Years Ago Event 133-120 Origin of Asparagales, i.e. firs... |
Asparagales | Comparison of family structures | Comparison of family structures
The taxonomic diversity of the monocotyledons is described in detail by Kubitzki. Up-to-date information on the Asparagales can be found on the Angiosperm Phylogeny Website.
The APG III system's family circumscriptions are being used as the basis of the Kew-hosted World Checklist o... |
Asparagales | Uses | Uses
The Asparagales include many important crop plants and ornamental plants. Crops include Allium, Asparagus and Vanilla, while ornamentals include irises, hyacinths and orchids. |
Asparagales | See also | See also
Taxonomy of Liliaceae |
Asparagales | Notes | Notes |
Asparagales | References | References |
Asparagales | Bibliography | Bibliography |
Asparagales | Books | Books
contents
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Asparagales | Chapters | Chapters
in
in
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in
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Asparagales | Articles | Articles
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Asparagales | APG | APG
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Asparagales | Historical sources | Historical sources
digital edition by the University and State Library Düsseldorf
1st ed. 1901–1908; 2nd ed. 1910–1911; 3rd ed. 1923–1924; 4th ed. 1933–1935
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Asparagales | Websites | Websites
: Families included in the checklist
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Asparagales | Reference materials | Reference materials
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Asparagales | External links | External links
Biodiversity Heritage Library
Category:Angiosperm orders
Category:Extant Late Cretaceous first appearances |
Asparagales | Table of Content | Short description, Description, Taxonomy, History, Pre-Darwinian, Post-Darwinian, Twentieth century, Phylogenetics, Phylogeny and APG system, Subdivision, Changes to family structure in APG III, Structure of Asparagales, Orchid clade, Boryaceae to Hypoxidaceae, Ixioliriaceae to Xeronemataceae, Asphodelaceae + 'core Asp... |
Alismatales | Short description | thumb|220px|Snake lily (Dracunculus vulgaris) of family Araceae in Crete, Greece.
thumb|220px|Ottelia alismoides from family Hydrocharitaceae in Hyderabad, India.
The Alismatales (alismatids) are an order of flowering plants including about 4,500 species. Plants assigned to this order are mostly tropical or aquatic. S... |
Alismatales | Description | Description
The Alismatales comprise herbaceous flowering plants of often aquatic and marshy habitats, and the only monocots known to have green embryos other than the Amaryllidaceae. They also include the only marine angiosperms growing completely submerged, the seagrasses. The flowers are usually arranged in inflores... |
Alismatales | Taxonomy | Taxonomy
The Alismatales contain about 165 genera in 13 families, with a cosmopolitan distribution. Phylogenetically, they are basal monocots, diverging early in evolution relative to the lilioid and commelinid monocot lineages. Together with the Acorales, the Alismatales are referred to informally as the alismatid mon... |
Alismatales | Early systems | Early systems
The Cronquist system (1981) places the Alismatales in subclass Alismatidae, class Liliopsida [= monocotyledons] and includes only three families as shown:
Alismataceae
Butomaceae
Limnocharitaceae
Cronquist's subclass Alismatidae conformed fairly closely to the order Alismatales as defined by APG, minus... |
Alismatales | Angiosperm Phylogeny Group | Angiosperm Phylogeny Group
The Angiosperm Phylogeny Group system (APG) of 1998 and APG II (2003) assigned the Alismatales to the monocots, which may be thought of as an unranked clade containing the families listed below. The biggest departure from earlier systems (see below) is the inclusion of family Araceae. By its ... |
Alismatales | Phylogeny | Phylogeny
Cladogram showing the orders of monocots (Lilianae sensu Chase & Reveal) based on molecular phylogenetic evidence: |
Alismatales | References | References |
Alismatales | Further reading | Further reading
B. C. J. du Mortier 1829. Analyse des Familles de Plantes : avec l'indication des principaux genres qui s'y rattachent. Imprimerie de J. Casterman, Tournay
W. S. Judd, C. S. Campbell, E. A. Kellogg, P. F. Stevens, M. J. Donoghue, 2002. Plant Systematics: A Phylogenetic Approach, 2nd edition. Sinaue... |
Alismatales | External links | External links
Category:Angiosperm orders |
Alismatales | Table of Content | Short description, Description, Taxonomy, Early systems, Angiosperm Phylogeny Group, Phylogeny, References, Further reading, External links |
Apiales | Short description | The Apiales are an order of flowering plants, included in the asterid group of dicotyledons. Well-known members of Apiales include carrots, celery, coriander, parsley, parsnips, poison hemlock, ginseng, ivies, and pittosporums.
Apiales consist of nine families, with the type family being the celery, carrot or parsley ... |
Apiales | Taxonomy | Taxonomy
There are nine accepted families within the Apiales, though there is some slight variation and in particular, the Torriceliaceae may also be divided.
Apiaceae (carrot family)
Araliaceae (ginseng family)
Griseliniaceae
Myodocarpaceae
Pennantiaceae
Pittosporaceae
Torricelliaceae
The present understandin... |
Apiales | Gynoecia | Gynoecia
The largest and obviously closely related families of Apiales are Araliaceae, Myodocarpaceae and
Apiaceae, which resemble each other in the structure of their gynoecia. In this respect however, the Pittosporaceae is notably distinct from them.
Typical syncarpous gynoecia exhibit four vertical zones, determine... |
Apiales | References | References
Category:Angiosperm orders
Category:Taxa named by Takenoshin Nakai |
Apiales | Table of Content | Short description, Taxonomy, Gynoecia, References |
Asterales | Short description | Asterales ( ) is an order of dicotyledonous flowering plants that includes the large family Asteraceae (or Compositae) known for composite flowers made of florets, and ten families related to the Asteraceae. While asterids in general are characterized by fused petals, composite flowers consisting of many florets create... |
Asterales | Taxonomy | Taxonomy
The name and order Asterales is botanically venerable, dating back to at least 1926 in the Hutchinson system of plant taxonomy when it contained only five families, of which only two are retained in the APG III classification. Under the Cronquist system of taxonomic classification of flowering plants, Astera... |
Asterales | Phylogeny | Phylogeny
Although most extant species of Asteraceae are herbaceous, the examination of the basal members in the family suggests that the common ancestor of the family was an arborescent plant, a tree or shrub, perhaps adapted to dry conditions, radiating from South America. Less can be said about the Asterales thems... |
Asterales | Biogeography | Biogeography
The core Asterales are Stylidiaceae (six genera), APA clade (Alseuosmiaceae, Phellinaceae and Argophyllaceae, together seven genera), MGCA clade (Menyanthaceae, Goodeniaceae, Calyceraceae, in total twenty genera), and Asteraceae (about sixteen hundred genera). Other Asterales are Rousseaceae (four genera),... |
Asterales | Uses | Uses
The Asterales, by dint of being a super-set of the family Asteraceae, include some species grown for food, including the sunflower (Helianthus annuus), lettuce (Lactuca sativa) and chicory (Cichorium). Many are also used as spices and traditional medicines.
Asterales are common plants and have many known uses. Fo... |
Asterales | References | References |
Asterales | Further reading | Further reading
W. S. Judd, C. S. Campbell, E. A. Kellogg, P. F. Stevens, M. J. Donoghue (2002). Plant Systematics: A Phylogenetic Approach, 2nd edition. pp. 476–486 (Asterales). Sinauer Associates, Sunderland, Massachusetts. .
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Asterales | External links | External links
Category:Angiosperm orders |
Asterales | Table of Content | Short description, Taxonomy, Phylogeny, Biogeography, Uses, References, Further reading, External links |
Asteroid | Short description | An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the inner Solar System or is co-orbital with Jupiter (Trojan asteroids). Asteroids are rocky, metallic, or icy bodies with no atmosphere, and are broadly classified into C-type (carbonaceo... |
Asteroid | Terminology{{anchor | Terminology
In 2006, the International Astronomical Union (IAU) introduced the currently preferred broad term small Solar System body, defined as an object in the Solar System that is neither a planet, a dwarf planet, nor a natural satellite; this includes asteroids, comets, and more recently discovered classes. Acc... |
Asteroid | History of observations | History of observations
Despite their large numbers, asteroids are a relatively recent discovery, with the first one—Ceres—only being identified in 1801. Only one asteroid, 4 Vesta, which has a relatively reflective surface, is normally visible to the naked eye in dark skies when it is favorably positioned. Rarely, s... |
Asteroid | Discovery of Ceres | Discovery of Ceres
In 1772, German astronomer Johann Elert Bode, citing Johann Daniel Titius, published a numerical procession known as the Titius–Bode law (now discredited). Except for an unexplained gap between Mars and Jupiter, Bode's formula seemed to predict the orbits of the known planets. He wrote the following ... |
Asteroid | Further search | Further search
thumb|left|Sizes of the first ten discovered asteroids, compared to the Moon
Three other asteroids (2 Pallas, 3 Juno, and 4 Vesta) were discovered by von Zach's group over the next few years, with Vesta found in 1807. No new asteroids were discovered until 1845. Amateur astronomer Karl Ludwig Hencke sta... |
Asteroid | 19th and 20th centuries | 19th and 20th centuries
thumb|Cumulative discoveries of just the near-Earth asteroids known by size, 1980–2024
In the past, asteroids were discovered by a four-step process. First, a region of the sky was photographed by a wide-field telescope or astrograph. Pairs of photographs were taken, typically one hour apart.... |
Asteroid | Naming | Naming
thumb|right|2013 EC, shown here in radar images, has a provisional designation
By 1851, the Royal Astronomical Society decided that asteroids were being discovered at such a rapid rate that a different system was needed to categorize or name asteroids. In 1852, when de Gasparis discovered the twentieth aster... |
Asteroid | Symbols | Symbols
The first asteroids to be discovered were assigned iconic symbols like the ones traditionally used to designate the planets. By 1852 there were two dozen asteroid symbols, which often occurred in multiple variants.
In 1851, after the fifteenth asteroid, Eunomia, had been discovered, Johann Franz Encke made ... |
Asteroid | Formation | Formation
Many asteroids are the shattered remnants of planetesimals, bodies within the young Sun's solar nebula that never grew large enough to become planets. It is thought that planetesimals in the asteroid belt evolved much like the rest of objects in the solar nebula until Jupiter neared its current mass, at wh... |
Asteroid | Distribution within the Solar System | Distribution within the Solar System
thumb|A top view of asteroid group location in the inner solar system|350x350px
thumb|A map of planets and asteroid groups of the inner solar system. Distances from sun are to scale, object sizes are not.
Various dynamical groups of asteroids have been discovered orbiting in the... |
Asteroid | Asteroid belt | Asteroid belt
The majority of known asteroids orbit within the asteroid belt between the orbits of Mars and Jupiter, generally in relatively low-eccentricity (i.e. not very elongated) orbits. This belt is estimated to contain between 1.1 and 1.9 million asteroids larger than in diameter, and millions of smaller one... |
Asteroid | Trojans | Trojans
Trojans are populations that share an orbit with a larger planet or moon, but do not collide with it because they orbit in one of the two Lagrangian points of stability, and , which lie 60° ahead of and behind the larger body.
In the Solar System, most known trojans share the orbit of Jupiter. They are div... |
Asteroid | Near-Earth asteroids | Near-Earth asteroids
Near-Earth asteroids, or NEAs, are asteroids that have orbits that pass close to that of Earth. Asteroids that actually cross Earth's orbital path are known as Earth-crossers. , a total of 28,772 near-Earth asteroids were known; 878 have a diameter of one kilometer or larger.
A small number of ... |
Asteroid | Martian moons | Martian moons
It is unclear whether Martian moons Phobos and Deimos are captured asteroids or were formed due to impact event on Mars.Burns, Joseph A. (1992). "Contradictory Clues as to the Origin of the Martian Moons" in Mars, H. H. Kieffer et al., eds., Tucson: University of Arizona Press, Tucson Phobos and Deimo... |
Asteroid | Characteristics | Characteristics |
Asteroid | Size distribution | Size distribution
thumb|The asteroids of the Solar System, categorized by size and number|300x300px
Asteroids vary greatly in size, from almost for the largest down to rocks just 1 meter across, below which an object is classified as a meteoroid. The three largest are very much like miniature planets: they are roug... |
Asteroid | Largest asteroids | Largest asteroids
Three largest objects in the asteroid belt, Ceres, Vesta, and Pallas, are intact protoplanets that share many characteristics common to planets, and are atypical compared to the majority of irregularly shaped asteroids. The fourth-largest asteroid, Hygiea, appears nearly spherical although it may hav... |
Asteroid | Rotation | Rotation
Measurements of the rotation rates of large asteroids in the asteroid belt show that there is an upper limit. Very few asteroids with a diameter larger than 100 meters have a rotation period less than 2.2 hours. For asteroids rotating faster than approximately this rate, the inertial force at the surface is... |
Asteroid | Color | Color
Asteroids become darker and redder with age due to space weathering. However evidence suggests most of the color change occurs rapidly, in the first hundred thousand years, limiting the usefulness of spectral measurement for determining the age of asteroids. |
Asteroid | Surface features | Surface features
thumb|Cratered terrain on 4 Vesta
Except for the "big four" (Ceres, Pallas, Vesta, and Hygiea), asteroids are likely to be broadly similar in appearance, if irregular in shape. 253 Mathilde is a rubble pile saturated with craters with diameters the size of the asteroid's radius. Earth-based observa... |
Asteroid | Composition | Composition
Asteroids are classified by their characteristic emission spectra, with the majority falling into three main groups: C-type, M-type, and S-type. These describe carbonaceous (carbon-rich), metallic, and silicaceous (stony) compositions, respectively. The physical composition of asteroids is varied and in m... |
Asteroid | Water | Water
Scientists hypothesize that some of the first water brought to Earth was delivered by asteroid impacts after the collision that produced the Moon. In 2009, the presence of water ice was confirmed on the surface of 24 Themis using NASA's Infrared Telescope Facility. The surface of the asteroid appears completel... |