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GALEX J2339–0424
GALEX J2339–0424 (GALEX J233917.0–042425, GALEX J2339) is a white dwarf that is suspected to be polluted with material originating from an icy exomoon. This is evident from the first detection of beryllium in this white dwarf, together with GD 378. GALEX J2339 was first identified as a possible quasar with GALEX in 2007. It was identified as a white dwarf candidate from Gaia and virtual observatory data in 2018. In 2020 it was identified as a DBAZ: white dwarf, which means that it had helium, hydrogen and metal absorption lines. In 2021 the white dwarf was observed with Lick, Magellan 1 and Keck. The observations showed that the object had absorption due to hydrogen, helium, beryllium, oxygen, magnesium, silicon, calcium, titanium, chromium, manganese and iron. The oxygen is present in excess, which indicates a water ice-rich body. The accreted parent object had a chondrite-like composition and was 85% water ice in volume. The accretion event lasted for 2–4 Milli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magellan Telescopes
The Magellan Telescopes are a pair of optical telescopes located at Las Campanas Observatory in Chile. The two telescopes are named after the astronomer Walter Baade and the philanthropist Landon T. Clay. First light for the telescopes was on September 15, 2000 for the Baade, and September 7, 2002 for the Clay. A consortium consisting of the Carnegie Institution for Science, University of Arizona, Harvard University, the University of Michigan and the Massachusetts Institute of Technology built and operate the twin telescopes. The telescopes were named after the sixteenth-century Portuguese explorer Ferdinand Magellan. The Giant Magellan Telescope (GMT) is an extremely large telescope under construction, as part of the US Extremely Large Telescope Program. Current instruments on the Magellan Telescopes Baade telescope: * Inamori Magellan Areal Camera and Spectrograph (IMACS) * FourStar * Folded port InfraRed Echellette (FIRE) * Magellan Echellete (MagE) Clay telescope: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant Planet
A giant planet, sometimes referred to as a jovian planet (''Jove'' being another name for the Roman god Jupiter (mythology), Jupiter), is a diverse type of planet much larger than Earth. Giant planets are usually primarily composed of low-boiling point materials (volatile (astrogeology), volatiles), rather than rock (geology), rock or other solid matter, but massive solid planets can also exist. There are four such planets in the Solar System: Jupiter, Saturn, Uranus, and Neptune. Many exoplanet, extrasolar giant planets have been identified. Giant planets are sometimes known as gas giants, but many astronomers now apply the term only to Jupiter and Saturn, classifying Uranus and Neptune, which have different compositions, as ice giants. Both names are potentially misleading; the Solar System's giant planets all consist primarily of fluids above their critical point (thermodynamics), critical points, where distinct gas and liquid phases do not exist. Jupiter and Saturn are princip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosmic Ray Spallation
Cosmic ray spallation, also known as the x-process, is a set of naturally occurring nuclear reactions causing nucleosynthesis; it refers to the formation of chemical elements from the impact of cosmic rays on an object. Cosmic rays are highly energetic charged particles from beyond Earth, ranging from protons, alpha particles, and nuclei of many heavier elements. About 1% of cosmic rays also consist of free electrons. Cosmic rays cause spallation when a ray particle (e.g. a proton) impacts with matter, including other cosmic rays. The result of the collision is the expulsion of particles (protons, neutrons, and alpha particles) from the object hit. This process goes on not only in deep space, but in Earth's upper atmosphere and crustal surface (typically the upper ten meters) due to the ongoing impact of cosmic rays. The process Cosmic ray spallation is thought to be responsible for the abundance in the universe of some light elements—lithium, beryllium, and boron—as well ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceres (dwarf Planet)
Ceres (minor-planet designation: 1 Ceres) is a dwarf planet in the middle main asteroid belt between the orbits of Mars and Jupiter. It was the first known asteroid, discovered on 1 January 1801 by Giuseppe Piazzi at Palermo Astronomical Observatory in Sicily, and announced as a new planet. Ceres was later classified as an asteroid and then a dwarf planet, the only one not beyond Neptune's orbit. Ceres's diameter is about a quarter that of the Moon. Its small size means that even at its brightest it is too dim to be seen by the naked eye, except under extremely dark skies. Its apparent magnitude ranges from 6.7 to 9.3, peaking at opposition (planets), opposition (when it is closest to Earth) once every 15- to 16-month synodic period. As a result, its surface features are barely visible even with the most powerful telescopes, and little was known about it until the robotic NASA spacecraft Dawn (spacecraft), ''Dawn'' approached Ceres for its orbital mission in 2015. ''Dawn'' fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4 Vesta
Vesta (minor-planet designation: 4 Vesta) is one of the largest objects in the asteroid belt, with a mean diameter of . It was discovered by the German astronomer Heinrich Wilhelm Matthias Olbers on 29 March 1807 and is named after Vesta (mythology), Vesta, the virgin goddess of home and hearth from Roman mythology. Vesta is thought to be the second-largest asteroid, both by mass and by volume, after the dwarf planet Ceres (dwarf planet), Ceres. Measurements give it a nominal volume only slightly larger than that of 2 Pallas, Pallas (about 5% greater), but it is 25% to 30% more massive. It constitutes an estimated 9% of the mass of the asteroid belt. Vesta is the only known remaining rocky protoplanet of the kind that formed the terrestrial planets. Numerous fragments of Vesta were ejected by collisions one and two billion years ago that left two enormous craters occupying much of Vesta's southern hemisphere. Debris from these events has fallen to Earth as HED meteorite, howardi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chondrite
A chondrite is a stony (non-metallic) meteorite that has not been modified by either melting or planetary differentiation, differentiation of the parent body. They are formed when various types of dust and small grains in the early Solar System accreted to form primitive asteroids. Some such bodies that are captured in the planet's gravity well become the most common type of meteorite by arriving on a trajectory toward the planet's surface. Estimates for their contribution to the total meteorite population vary between 85.7% and 86.2%. Their study provides important clues for understanding the origin and age of the Solar System, the synthesis of organic compounds, the Abiogenesis, origin of life and the presence of water on Earth. One of their characteristics is the presence of chondrules (from the Ancient Greek χόνδρος ''chondros'', grain), which are round grains formed in space as molten or partially molten droplets of distinct minerals. Chondrules typically constitute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's outer and inner core. It is the fourth most abundant element in the Earth's crust, being mainly deposited by meteorites in its metallic state. Extracting usable metal from iron ores requires kilns or furnaces capable of reaching , about 500 °C (900 °F) higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BC and the use of iron tools and weapons began to displace copper alloys – in some regions, only around 1200 BC. That event is considered the transition from the Bronze Age to the Iron Age. In the modern world, iron alloys, such as steel, stainless steel, cast iron and special steels, are by far the most common industrial metals, due to their mechan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese
Manganese is a chemical element; it has Symbol (chemistry), symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese was first isolated in the 1770s. It is a transition metal with a multifaceted array of industrial alloy uses, particularly in stainless steels. It improves strength, workability, and resistance to wear. Manganese oxide is used as an oxidising agent, as a rubber additive, and in glass making, fertilisers, and ceramics. Manganese sulfate can be used as a fungicide. Manganese is also an essential human dietary element, important in macronutrient metabolism, bone formation, and free radical defense systems. It is a critical component in dozens of proteins and enzymes. It is found mostly in the bones, but also the liver, kidneys, and brain. In the human brain, the manganese is bound to manganese metalloproteins, most notably glutamine synthetase in astrocytes. Manganese is commonly found in labo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromium
Chromium is a chemical element; it has Symbol (chemistry), symbol Cr and atomic number 24. It is the first element in Group 6 element, group 6. It is a steely-grey, Luster (mineralogy), lustrous, hard, and brittle transition metal. Chromium is valued for its high corrosion resistance and hardness. A major development in steel production was the discovery that steel could be made highly resistant to corrosion and discoloration by adding metallic chromium to form stainless steel. Stainless steel and chrome plating (electroplating with chromium) together comprise 85% of the commercial use. Chromium is also greatly valued as a metal that is able to be highly polishing, polished while resisting tarnishing. Polished chromium reflects almost 70% of the visible spectrum, and almost 90% of infrared, infrared light. The name of the element is derived from the Ancient Greek, Greek word χρῶμα, ''chrōma'', meaning color, because many chromium compounds are intensely colored. Indust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanium
Titanium is a chemical element; it has symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in sea water, aqua regia, and chlorine. Titanium was discovered in Cornwall, Great Britain, by William Gregor in 1791 and was named by Martin Heinrich Klaproth after the Titans of Greek mythology. The element occurs within a number of minerals, principally rutile and ilmenite, which are widely distributed in the Earth's crust and lithosphere; it is found in almost all living things, as well as bodies of water, rocks, and soils. The metal is extracted from its principal mineral ores by the Kroll and Hunter processes. The most common compound, titanium dioxide (TiO2), is a popular photocatalyst and is used in the manufacture of white pigments. Other compounds include titanium tetrachloride (TiCl4), a component of smoke screens and cata ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium
Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to its heavier homologues strontium and barium. It is the fifth most abundant element in Earth's crust, and the third most abundant metal, after iron and aluminium. The most common calcium compound on Earth is calcium carbonate, found in limestone and the fossils of early sea life; gypsum, anhydrite, fluorite, and apatite are also sources of calcium. The name comes from Latin ''calx'' " lime", which was obtained from heating limestone. Some calcium compounds were known to the ancients, though their chemistry was unknown until the seventeenth century. Pure calcium was isolated in 1808 via electrolysis of its oxide by Humphry Davy, who named the element. Calcium compounds are widely used in many industries: in foods and pharmaceuticals for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
