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Sutter's Mill Meteorite
The Sutter's Mill meteorite is a carbonaceous chondrite which entered the Earth's atmosphere and broke up at about 07:51 Pacific Time on April 22, 2012, with fragments landing in the United States. The name comes from Sutter's Mill, a California Gold Rush site, near which some pieces were recovered. Meteor astronomer Peter Jenniskens assigned Sutter's Mill (SM) numbers to each meteorite, with the documented find location preserving information about where a given meteorite was located in the impacting meteoroid. As of May 2014, 79 fragments had been publicly documented with a find location. The largest (SM53) weighs , and the second largest (SM50) weighs . The meteorite was found to contain some of the oldest material in the Solar System. Two 10-micron diamond grains (xenoliths) were found in meteorite fragments recovered before any rain fell as the rain would degrade the purity of the meteorites for scientific study. In primitive meteorites like Sutter's Mill, some grains survive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lotus, California
Lotus (formerly, Marshall and Uniontown) is an unincorporated community in El Dorado County, California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ..., United States. It is located west of Coloma, at an elevation of 722 feet (220 m). The settlement was established in 1849 and named for James W. Marshall, discoverer of gold. In 1850, the name was changed to Uniontown to commemorate California's admission to the Union. The name was changed to Lotus with the arrival of the post office in 1881. References Unincorporated communities in California Unincorporated communities in El Dorado County, California Populated places established in 1849 1849 establishments in California {{ElDoradoCountyCA-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pacific Daylight Time
The Pacific Time Zone (PT) is a time zone encompassing parts of western Canada, the western United States, and western Mexico. Places in this zone observe standard time by subtracting eight hours from Coordinated Universal Time ( UTC−08:00). During daylight saving time, a time offset of UTC−07:00 is used. In the United States and Canada, this time zone is generically called the Pacific Time Zone. Specifically, time in this zone is referred to as Pacific Standard Time (PST) when standard time is being observed (early November to mid-March), and Pacific Daylight Time (PDT) when daylight saving time (mid-March to early November) is being observed. In Mexico, the corresponding time zone is known as the ''Zona Noroeste'' (Northwest Zone) and observes the same daylight saving schedule as the U.S. and Canada. The largest city in the Pacific Time Zone is Los Angeles, whose metropolitan area is also the largest in the time zone. The zone is two hours ahead of the Hawaii–Aleut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Murchison Meteorite
The Murchison meteorite is a meteorite that fell in Australia in 1969 near Murchison, Victoria. It belongs to the carbonaceous chondrite class, a group of meteorites rich in organic compounds. Due to its mass (over ) and the fact that it was an observed fall, the Murchison meteorite is one of the most studied of all meteorites. In January 2020, cosmochemists reported that the oldest material found on Earth to date are the silicon carbide particles from the Murchison meteorite, which have been determined to be 7 billion years old, about 2.5 billion years older than the 4.54-billion-year age of the Earth and the Solar System. The published study noted that "dust lifetime estimates mainly rely on sophisticated theoretical models. These models, however, focus on the more common small dust grains and are based on assumptions with large uncertainties." History On 28 September 1969 at approximately 10:58 a.m. local time, near Murchison, Victoria, in Australia, a bright ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strewn Field
The term strewn field indicates the area where meteorites from a single fall are dispersed. It is also often used for the area containing tektites produced by large meteorite impact.''Tektites in the geological record: showers of glass from the sky''. Gerald Joseph Home McCall. Geological Society of London, 2001page 10/ref> Formation There are two strewnfield formation mechanisms: # Mid-air fragmentation: when a large meteoroid enters the atmosphere it often fragments into many pieces before touching the ground due to thermal shock. This mid-air explosion disperses material over a large oval-shaped area. The long axis of this oval is along the flight path of the meteoroid. When multiple-explosions occur, the material can be found in several overlapping ovals. # Impact fragmentation: when there is almost no mid-air fragmentation the fragmentation can occur upon impact. In this case the strewnfield shape can be different, usually circular. (e.g. Canyon Diablo at Meteor Crater; Austra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airship
An airship or dirigible balloon is a type of aerostat or lighter-than-air aircraft that can navigate through the air under its own power. Aerostats gain their lift from a lifting gas that is less dense than the surrounding air. In early dirigibles, the lifting gas used was hydrogen, due to its high lifting capacity and ready availability. Helium gas has almost the same lifting capacity and is not flammable, unlike hydrogen, but is rare and relatively expensive. Significant amounts were first discovered in the United States and for a while helium was only available for airships in that country. Most airships built since the 1960s have used helium, though some have used hot air.A few airships after World War II used hydrogen. The first British airship to use helium was the ''Chitty Bang Bang'' of 1967. The envelope of an airship may form the gasbag, or it may contain a number of gas-filled cells. An airship also has engines, crew, and optionally also payload accommodation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SETI Institute
The SETI Institute is a not-for-profit research organization incorporated in 1984 whose mission is to explore, understand, and explain the origin and nature of life in the universe, and to use this knowledge to inspire and guide present and future generations, sharing knowledge with the public, the press, and the government. SETI stands for the "search for extraterrestrial intelligence". The institute consists of three primary centers: The Carl Sagan Center, devoted to the study of life in the universe; the Center for Education, focused on astronomy, astrobiology and space science for students and educators; and the Center for Public Outreach, which produces " Big Picture Science", the institute's general science radio show and podcast, and "SETI Talks", its weekly colloquium series. Primary centers Carl Sagan Center The Carl Sagan Center is named in honor of Carl Sagan, former trustee of the institute, astronomer, prolific author and host of the original "Cosmos" television se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ames Research Center
The Ames Research Center (ARC), also known as NASA Ames, is a major NASA research center at Moffett Federal Airfield in California's Silicon Valley. It was founded in 1939 as the second National Advisory Committee for Aeronautics (NACA) laboratory. That agency was dissolved and its assets and personnel transferred to the newly created National Aeronautics and Space Administration (NASA) on October 1, 1958. NASA Ames is named in honor of Joseph Sweetman Ames, a physicist and one of the founding members of NACA. At last estimate NASA Ames had over US$3 billion in capital equipment, 2,300 research personnel and a US$860 million annual budget. Ames was founded to conduct wind-tunnel research on the aerodynamics of propeller-driven aircraft; however, its role has expanded to encompass spaceflight and information technology. Ames plays a role in many NASA missions. It provides leadership in astrobiology; small satellites; robotic lunar exploration; the search for habitable planets; s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marshall Gold Discovery State Historic Park
Marshall Gold Discovery State Historic Park is a state park of California, United States, marking the discovery of gold by James W. Marshall at Sutter's Mill in 1848, sparking the California Gold Rush. The park grounds include much of the historic town of Coloma, California, which is now considered a ghost town as well as a National Historic Landmark District. The park contains two California Historical Landmarks: a monument to commemorate James Marshall (#143) and the actual spot where he first discovered gold in 1848 (#530). Established in 1942, the park now comprises . Features The entire route of California State Route 153 lies within the park, and allows visitors to drive to the top of the hill where the monument to James W. Marshall stands. The Gold Discovery Museum features gold-rush-era exhibits including mining equipment, horse-drawn vehicles, household implements and other memorabilia. The American River Nature Center, operated by the American River Conservancy, fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coloma, CA
Coloma (Nisenan: ''Cullumah'', meaning "beautiful") is a census-designated place in El Dorado County, California, US. It is approximately northeast of Sacramento, California. Coloma is most noted for being the site where James W. Marshall found gold in the Sierra Nevada foothills, at Sutter's Mill on January 24, 1848, leading to the California Gold Rush. Coloma's population is 529. The settlement is a tourist attraction known for its ghost town and the centerpiece of the Marshall Gold Discovery State Historic Park. Coloma was designated a National Historic Landmark District on July 4, 1961. and It lies at an elevation of 764 feet (233 m). Etymology The name comes from the Nisenan Indian name for the valley in which Coloma is located: ''Cullumah'', meaning 'beautiful.' Coloma is on the South Fork American River that runs through the valley and was built on the original Indian village of Koloma. Former spellings include "Colluma" and "Culloma".. History Coloma grew aroun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CM Chondrite
CM chondrites are a group of chondritic meteorites which resemble their type specimen, the Mighei meteorite. The CM is the most commonly recovered group of the 'carbonaceous chondrite' class of meteorites, though all are rarer in collections than ordinary chondrites. Overview and Taxonomy Meteorites mostly divide into Ordinary and 'Carbonaceous' chondrite classes; far fewer belong to lesser classes like Enstatites and Ureilites. The term 'chondrite' indicates that these contain (or may have contained) chondrules in a matrix. Chondrules are cooled droplets of minerals, predating the meteorites themselves. The term 'carbonaceous' was assigned relative to the ordinary chondrites; some Enstatite and Ureilite meteorites may have more carbon than C-chondrites. Still, all C-chondrites are distinguished from ordinary chondrites by a non-trace carbon content (resulting in a dark color), plus other volatiles, giving a lower density. After the classes were devised, a more rigorous definiti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placerville, California
Placerville (, ; formerly Old Dry Diggings, Dry Diggings, and Hangtown) is a city in and the county seat of El Dorado County, California. The population was 10,747 as of the 2020 census, up from 10,389 as of the 2010 census. It is part of the Sacramento–Arden-Arcade– Roseville Metropolitan Statistical Area. History A former Maidu settlement called Indak was located at the site of the town. After the discovery of gold at Sutter's Mill in nearby Coloma, California, by James W. Marshall in 1848 sparked the California Gold Rush, the small town now known as Placerville was known as Dry Diggin's after the manner in which the miners moved cartloads of dry soil to run water to separate the gold from the soil. Later in 1849, the town earned its most common historical name, "Hangtown", because of the numerous hangings that had occurred there. However, there is debate on exactly how many lynchings occurred in the town. The town had no police force (in 1849) and five immigra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auburn, California
Auburn is a city in and the county seat of Placer County, California, United States. Its population was 13,776 during the 2020 census. Auburn is known for its California Gold Rush history and is registered as a California Historical Landmark. Auburn is part of the Sacramento metropolitan area. History Archaeological finds place the southwestern border for the prehistoric Martis people in the Auburn area. The indigenous Nisenan, an offshoot of the Maidu, were the first to establish a permanent settlement in the Auburn area. In the spring of 1848, a group of French gold miners arrived and camped in what would later be known as the Auburn Ravine. This group was on its way to the gold fields in Coloma, California, and it included Francois Gendron, Philibert Courteau, and Claude Chana. The young Chana discovered gold on May 16, 1848. After finding the gold deposits in the soil, the trio decided to stay for more prospecting and mining. Placer mining in the Auburn area was very goo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
