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1999 In Science
The year 1999 in science and technology involved some significant events. Aeronautics * February 27 – While trying to circumnavigation, circumnavigate the world in a hot air balloon, Colin Prescot and Andy Elson set a new endurance record after being in their balloon for 233 hours and 55 minutes. * March 3–20 – Bertrand Piccard and Brian Jones (aeronaut), Brian Jones successfully complete a non-stop circumnavigation of the world in a hot air balloon. Astronomy and space exploration * January 31 – January 1999 lunar eclipse, A total penumbral lunar eclipse. * February 7 – ''Stardust (spacecraft), Stardust'' is launched on a mission to collect samples of a comet coma (cometary), coma, and return them to Earth. * February 16 – Solar eclipse of February 16, 1999, Annular solar eclipse, visible from Australia. * July 20 – Mercury program: ''Liberty Bell 7'' is raised from the Atlantic Ocean. * July 28 – July 1999 lunar eclipse, Partial lunar eclipse, visible fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar Prospector
''Lunar Prospector'' was a spacecraft that orbited the Moon for 19 months in 1998-99. From a low polar orbit, it mapped surface composition including lunar hydrogen deposits, measured magnetic and gravity fields, and studied lunar outgassing events. The mission ended July 31, 1999, when the orbiter was deliberately crashed into a crater near the lunar south pole. Data from the mission provided detailed mapping of the surface composition of the Moon, and helped to improve understanding of the origin, evolution, current state, and resources of the Moon. The mission identified the presence of hydrogen, implying deposits of ice on the Moon. Several articles on the scientific results were published in the journal ''Science''. ''Lunar Prospector'' was the third mission selected by NASA for full development and construction as part of the Discovery Program. It was managed by NASA Ames Research Center with the prime contractor being Lockheed Martin; it cost $62.8 million. The Prin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M–sigma Relation
The M–sigma (or ''M''–''σ'') relation is an empirical correlation between the stellar velocity dispersion ''σ'' of a galaxy bulge and the mass M of the supermassive black hole at its center. The ''M''–''σ'' relation was first presented in 1999 during a conference at the Institut d'Astrophysique de Paris in France. The proposed form by David Merritt of the relation, which was called the "Faber–Jackson law for black holes", was : \frac \approx 3.1\left(\frac\right)^4. where M_\odot is the solar mass. Publication of the relation in a refereed journal, by two groups, took place the following year. One of many recent studies, based on the growing sample of published black hole masses in nearby galaxies, givesMcConnell, N. J. et al. (2011) Two ten-billion-solar-mass black holes at the centres of giant elliptical galaxies ''Nature'', 480, 215–218 : \frac \approx 1.9\left(\frac\right)^. Earlier work demonstrated a relationship between galaxy luminosity and black hol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetus Dwarf
Cetus Dwarf is a dwarf spheroidal galaxy. It lies approximately 2.46 Million light-years from Earth. It is an isolated galaxy of the Local Group, which also contains the Milky Way. All of the most readily observable stars in the galaxy are red giants. History The Cetus Dwarf was discovered in 1999 by Alan B. Whiting, George Hau and Mike Irwin and was found to be a member of the Local Group. Characteristics As of 2000, no known neutral hydrogen The hydrogen line, 21 centimeter line, or H I line is a spectral line that is created by a change in the energy state of solitary, electrically neutral hydrogen atoms. It is produced by a spin-flip transition, which means the directio ... gas has been found that is related to the Cetus dwarf galaxy. References External links * {{DEFAULTSORT:Cetus Dwarf Dwarf spheroidal galaxies Local Group Cetus 3097691 Astronomical objects discovered in 1999 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mauna Kea Observatory
The Mauna Kea Observatories (MKO) are a group of independent astronomical research facilities and large telescope observatories that are located at the summit of Mauna Kea on Hawaiʻi, United States. The facilities are located in a 525-acre (212 ha) special land use zone known as the "Astronomy Precinct", which is located within the 11,228-acre (4,544 ha) Mauna Kea Science Reserve. The Astronomy Precinct was established in 1967 and is located on land protected by the Historical Preservation Act for its significance to Hawaiian culture. The presence and continued construction of telescopes is highly controversial due to Mauna Kea's centrality in native Hawaiian religion and culture, as well as for a variety of environmental reasons. The location is near ideal because of its dark skies from lack of light pollution, good astronomical seeing, low humidity, high elevation of , position above most of the water vapor in the atmosphere, clean air, good weather and low latit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reflecting Telescope
A reflecting telescope (also called a reflector) is a telescope that uses a single or a combination of curved mirrors that reflect light and form an image. The reflecting telescope was invented in the 17th century by Isaac Newton as an alternative to the refracting telescope which, at that time, was a design that suffered from severe chromatic aberration. Although reflecting telescopes produce other types of optical aberrations, it is a design that allows for very large diameter Objective (optics), objectives. Almost all of the major telescopes used in astronomy research are reflectors. Many variant forms are in use and some employ extra optical elements to improve image quality or place the image in a mechanically advantageous position. Since reflecting telescopes use mirrors, the design is sometimes referred to as a catoptrics, catoptric telescope. From the time of Newton to the 1800s, the mirror itself was made of metalusually speculum metal. This type included Newton's first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gemini Telescope
The Gemini Observatory comprises two 8.1-metre (26.6 ft) telescopes, Gemini North and Gemini South, situated in Hawaii and Chile, respectively. These twin telescopes offer extensive coverage of the northern and southern skies and rank among the most advanced optical/infrared telescopes available to astronomers. ''(See List of largest optical reflecting telescopes)''. The observatory is owned and operated by the National Science Foundation (NSF) of the United States, the National Research Council of Canada, CONICYT of Chile, MCTI of Brazil, MCTIP of Argentina, and Korea Astronomy and Space Science Institute (KASI) of Republic of Korea. The NSF is the primary funding contributor, providing about 70% of the required resources. The Association of Universities for Research in Astronomy (AURA) manages the operations and maintenance of the observatory through a cooperative agreement with the NSF, acting as the Executive Agency on behalf of the international partners. NSF's NOIRLa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subaru (telescope)
is the telescope of the National Astronomical Observatory of Japan, located at the Mauna Kea Observatory on Hawaii. It is named after the open star cluster known in English as the Pleiades. It had the largest monolithic primary mirror in the world from its commissioning until the Large Binocular Telescope opened in 2005. Overview The Subaru Telescope is a Ritchey-Chretien reflecting telescope. Instruments can be mounted at a Cassegrain focus below the primary mirror; at either of two Nasmyth focal points in enclosures on the sides of the telescope mount, to which light can be directed with a tertiary mirror; or at the prime focus in lieu of a secondary mirror, an arrangement rare on large telescopes, to provide a wide field of view suited to deep wide-field surveys. In 1984, the University of Tokyo formed an engineering working group to develop and study the concept of a telescope. In 1985, the astronomy committee of Japan's science council gave top priority to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars Polar Lander
The Mars Polar Lander, also known as the Mars Surveyor '98 Lander, was a 290-kilogram uncrewed spacecraft lander launched by NASA on January 3, 1999, to study the soil and climate of Planum Australe, a region near the south pole on Mars. It formed part of the Mars Surveyor '98 mission. On December 3, 1999, however, after the descent phase was expected to be complete, the lander failed to reestablish communication with Earth. A post-mortem analysis determined the most likely cause of the mishap was premature termination of the engine firing prior to the lander touching the surface, causing it to strike the planet at a high velocity. The total cost of the Mars Polar Lander was US$165 million. Spacecraft development cost US$110 million, launch was estimated at US$45 million, and mission operations at US$10 million. Mission background History As part of the Mars Surveyor '98 mission, a lander was sought as a way to gather climate data from the ground in conjunction with an orb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars Climate Orbiter
The ''Mars Climate Orbiter'' (formerly the Mars Surveyor '98 Orbiter) was a robotic space probe launched by NASA on December 11, 1998, to study the Martian climate, Martian atmosphere, and surface changes and to act as the communications relay in the Mars Surveyor '98 program for Mars Polar Lander. However, on September 23, 1999, communication with the spacecraft was permanently lost as it went into orbital insertion. The spacecraft encountered Mars on a trajectory that brought it too close to the planet, and it was destroyed in the atmosphere. An investigation attributed the failure to a measurement mismatch between two measurement systems: SI units (metric) by NASA and US customary units by spacecraft builder Lockheed Martin. Mission background History After the loss of '' Mars Observer'' and the onset of the rising costs associated with the future International Space Station, NASA began seeking less expensive, smaller probes for scientific interplanetary missions. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars
Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmospheric pressure is a few thousandths of Earth's, atmospheric temperature ranges from and cosmic radiation is high. Mars retains some water, in the ground as well as thinly in the atmosphere, forming cirrus clouds, frost, larger polar regions of permafrost and ice caps (with seasonal snow), but no liquid surface water. Its surface gravity is roughly a third of Earth's or double that of the Moon. It is half as wide as Earth or twice the Moon, with a diameter of , and has a surface area the size of all the dry land of Earth. Fine dust is prevalent across the surface and the atmosphere, being picked up and spread at the low Martian gravity even by the weak wind of the tenuous atmosphere. The terrain of Mars roughly follows a north-south ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gamma-ray Bursts
In gamma-ray astronomy, gamma-ray bursts (GRBs) are extremely energetic events occurring in distant galaxies which represent the brightest and most powerful class of explosion in the universe. These extreme electromagnetic emissions are second only to the Big Bang as the most energetic and luminous phenomenon ever known. Gamma-ray bursts can last from a few milliseconds to several hours. After the initial flash of gamma rays, a longer-lived afterglow is emitted, usually in the longer wavelengths of X-ray, ultraviolet, optical, infrared, microwave or radio frequencies. The intense radiation of most observed GRBs is thought to be released during a supernova or superluminous supernova as a high-mass star implodes to form a neutron star or a black hole. Short-duration (sGRB) events are a subclass of GRB signals that are now known to originate from the cataclysmic merger of binary neutron stars. The sources of most GRB are billions of light years away from Earth, implying that the e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
