A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects, the word telescope now refers to a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors. The first known practical telescopes were refracting telescopes with glass lenses and were invented in the Netherlands at the beginning of the 17th century. They were used for both terrestrial applications and astronomy. The reflecting telescope, which uses mirrors to collect and focus light, was invented within a few decades of the first refracting telescope. In the 20th century, many new types of telescopes were invented, including radio telescopes in the 1930s and infrared telescopes in the 1960s. Etymology The word telescope was coined in 1611 by the Greek mathematician Giovanni Demisiani for one of Galileo Galilei's instruments...

The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most versatile, renowned both as a vital research tool and as a public relations boon for astronomy. The Hubble telescope is named after astronomer Edwin Hubble and is one of NASA's Great Observatories. The Space Telescope Science Institute (STScI) selects Hubble's targets and processes the resulting data, while the Goddard Space Flight Center (GSFC) controls the spacecraft.Hubble features a 2.4 m (7 ft 10 in) mirror, and its five main instruments observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. Hubble's orbit outside the distortion of Earth's atmosphere allows it to capture extremely high-resolution images with substantially lower background light than ground-based telescopes. It has recorded some of the most detailed visible light images, allowing a deep view into space. Many Hubble observations have led to breakthroughs in astrophysics, such as determining...

Blanca (meaning "white" in Spanish) may refer to: Locations United States Casa Blanca, California or Blanca, a former unincorporated community Blanca, Colorado, a Statutory Town Blanca Peak, a mountain in Colorado Blanca Wetlands, a protected area in Colorado La Blanca, Texas, a census-designated place one of many early names of Galveston Island, Texas - see History of Galveston, Texas Blanca Lake, a lake in WashingtonElsewhere La Blanca, an archeological site in Guatemala Blanca, Sevnica, a settlement in Slovenia Blanca, Murcia, a town in Spain Isla Blanca (disambiguation)People Blanca (given name) Nida Blanca (1936–2001), Filipina actress Blanca (musician), a contemporary Christian music artistOther uses Blanca (album), by Christian musician Blanca Blanca, a 1971 film by Walerian Borowczyk...

A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects, the word telescope now refers to a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors. The first known practical telescopes were refracting telescopes with glass lenses and were invented in the Netherlands at the beginning of the 17th century. They were used for both terrestrial applications and astronomy. The reflecting telescope, which uses mirrors to collect and focus light, was invented within a few decades of the first refracting telescope. In the 20th century, many new types of telescopes were invented, including radio telescopes in the 1930s and infrared telescopes in the 1960s. Etymology The word telescope was coined in 1611 by the Greek mathematician Giovanni Demisiani for one of Galileo Galilei's instruments...

Cassata or cassata siciliana ( kə-SAH-tə, Italian: [kasˈsaːta sitʃiˈljaːna], Sicilian: [kasˈsaːta sɪʃɪˈljaːna]) is a traditional cake from Sicily, Italy. Cassata consists of round sponge cake moistened with fruit juices or liqueur and layered with ricotta cheese and candied fruit, a filling also used with cannoli. Cassata has a shell of marzipan, pink and green coloured icing, and decorative designs. Cassata may also refer to a Neapolitan ice cream containing candied or dried fruit and nuts. Origin Cassata is believed to have originated in Palermo in the 10th century, when under Muslim rule. The word al-qaššāṭī (القشاطي, Arabic for ''the cassata-maker'') was first mentioned in Corleone in 1178.The Arabic word qas'ah, from which...

The Chokwe people, known by many other names (including Kioko, Bajokwe, Chibokwe, Kibokwe, Ciokwe, Cokwe or Badjok), are an ethnic group of Central and Southern Africa. They are found primarily in Angola, southwestern parts of the Democratic Republic of the Congo (Kinshasa to Lualaba), and northwestern parts of Zambia. Demographics and language Estimated to be about 1.3 million, their language is usually referred to as Chokwe (or Kichokwe, Tshokwe), a Bantu language in the Benue-Congo branch of Niger-Congo family of languages.Many also speak the official languages of their countries: English in Zambia, French in Democratic Republic of Congo, and Portuguese (as first or second language) in Angola. History The Chokwe were once one of the twelve clans of the great Lunda Empire of 17th- and 18th-century Angola. They were initially employed by Lunda nobles, eventually became independent when they refused to continue paying tribute to the Lunda emperor. Their successful trading and abundant resources caused them to be one...

Natural science is one of the branches of science concerned with the description, understanding and prediction of natural phenomena, based on empirical evidence from observation and experimentation. Mechanisms such as peer review and repeatability of findings are used to try to ensure the validity of scientific advances. Natural science can be divided into two main branches: life science and physical science. Life science is alternatively known as biology, and physical science is subdivided into branches: physics, chemistry, earth science, and astronomy. These branches of natural science may be further divided into more specialized branches (also known as fields). As empirical...

A biologist is a scientist who conducts research in biology. Biologists are interested in studying life on Earth, whether it is an individual cell, a multicellular organism, or a community of interacting populations. They usually specialize in a particular branch (e.g., molecular biology, zoology, and evolutionary biology) of biology and have a specific research focus (e.g., studying malaria or cancer).Biologists who are involved in basic research have the aim of advancing knowledge about the natural world. They conduct their research using the scientific method, which is an empirical method for testing hypotheses. Their discoveries may have applications for some specific purpose such as in biotechnology, which has the goal of developing medically useful products for humans.In modern times, most biologists have one or more academic degrees such as a bachelor's degree plus an advanced degree like a master's degree or a doctorate. Like other scientists, biologists can be found working in different...

Ionic bonding is a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions, or between two atoms with sharply different electronegativities, and is the primary interaction occurring in ionic compounds. It is one of the main types of bonding, along with covalent bonding and metallic bonding. Ions are atoms (or groups of atoms) with an electrostatic charge. Atoms that gain electrons make negatively charged ions (called anions). Atoms that lose electrons make positively charged ions (called cations). This transfer of electrons is known as electrovalence in contrast to covalence. In the simplest case, the cation is a metal atom and the anion is a nonmetal atom, but these ions can be of a more complex nature, e.g. molecular ions like NH+4 or SO2−...

International Organization is a quarterly peer-reviewed academic journal that covers the entire field of international affairs. It was established in 1947 and is published by Cambridge University Press on behalf of the International Organization Foundation. The editor-in-chief is Erik Voeten (Georgetown University). International Organization is considered the leading journal in the field of International Relations, and one of the top journals in political science. In a 2005 survey of international relations scholars on "which journals publish articles that have the greatest impact" in their field, about 70% included International Organization among the 4 "top journals", ranking it first among 28 journals. According to the Journal Citation Reports, the journal has a 2017 impact factor of 4.517, ranking it 2nd out of 169 journals in the category "Political Science" and 1st out of 85 journals in the category "International Relations".The journal was founded in 1947 by the World Peace Foundation, a philanthropic institution. In its early years, the journal focused on the United Nations, but expanded its scope...