Space is dark and full of nightmares: asteroids, bolides, and comets, oh my.
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And I particularly love the Bolides, which are sculptures with pigment that he made himself.
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NASA keeps track of most of the notable fireballs and bolides (a similar astronomical term) that reach Earth.
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"Thus the possibility that cryopreserved squid and/or octopus eggs, arrived in icy bolides several hundred million years ago should not be discounted," the study reads.
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Bottom line: from an analysis of the brightness and duration of the 2000 flash, we can infer the impact energy, and [discern] when such bolides are likely to create detectable effects.
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Nuking asteroids to prevent the apocalypse sounds like science fiction, but among scientists working in planetary defense—a field concerned with safeguarding the Earth against deadly bolides—it's a delightfully legitimate idea.
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He also was a writer about bobsleigh, writing a book Bolides des glace (bobsleigh) in 1944.
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Unforeseen during the instrument design, GLM is able to detect Bolides in the atmosphere and thereby facilitates meteor sciences.
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Research employs photometry and astrometry of asteroids and comets using the main telescope of Skalnaté Pleso observatory. Furthermore, fish-eye cameras are used to detect bolides on the sky. The head of the department is Ján Svoreň.
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The first wave to reach the shore may not have the highest run-up. About 80% of tsunamis occur in the Pacific Ocean, but they are possible wherever there are large bodies of water, including lakes. They are caused by earthquakes, landslides, volcanic explosions, glacier calvings, and bolides.
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The brightest meteors known as bolides are long lasting fireballs that leave a trail in the sky which can be visible for up to an hour after passing. Such events are relatively rare but can be witnessed by a large area of the Earth since most events occur kilometers up in the atmosphere. Those witnessing such events who are not familiar with meteors can be easily fooled into thinking that the meteor is a UFO. Because meteors are not predictable with the same degree of accuracy as planets, stars, or man-made objects such as satellites, these occurrences are more difficult to prove in retrospect, though UFO sightings during meteor showers, or where there are astronomical reports of bolides, are likely to be explained as such.
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In the early-1930s he started his own meteoritical collection. After he failed with his requests to be allowed to study meteorites at the Smithsonian Institution, the Field Museum, and the American Museum of Natural History, he increased his collecting effort. He questioned witnesses of meteoroid detonations or bolides and organized and financed searching expeditions. He paid 1 dollar per pound, a price that museums could not match at the time of the Great Depression.
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Throughout recorded history, hundreds of Earth impacts (and exploding bolides) have been reported, with some occurrences causing deaths, injuries, property damage, or other significant localised consequences. One of the best-known recorded events in modern times was the Tunguska event, which occurred in Siberia, Russia, in 1908. The 2013 Chelyabinsk meteor event is the only known such incident in modern times to result in numerous injuries. Its meteor is the largest recorded object to have encountered the Earth since the Tunguska event.
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The comet currently has an Earth-MOID of . This coincidence means that streams from the comet at perihelion are still dense when they encounter Earth, resulting in the 33-year cycle of Leonid meteor storms. For example, in November 2009, the Earth passed through meteors left behind mainly from the 1466 and 1533 orbit. In February, 2016, two bolides detected by the NASA All-Sky Fireball Network were calculated to have orbits consistent with those of 55P, although with a node 100 degrees less than 55P.
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Many explosions recorded in Earth's atmosphere are likely to be caused by the air bursts that result from meteors exploding as they hit the thicker part of the atmosphere. These types of meteors are also known as fireballs or bolides with the brightest known as superbolides. Before entering Earth's atmosphere, these larger meteors were originally asteroids and comets of a few to several tens of metres in diameter, contrasting with the much smaller and much more common "shooting stars". The most powerful recorded air burst is the 1908 Tunguska event.
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Tollmann's bolide hypothesis is a hypothesis presented by Austrian paleontologist Edith Kristan-Tollmann and geologist Alexander Tollmann in 1994. The hypothesis postulates that one or several bolides (asteroids or comets) struck the Earth around 7640 ± 200 years BCE, with a much smaller one approximately 3150 ± 200 BCE. The hypothesis tries to explain early Holocene extinctions and possibly legends of the Universal Deluge. The claimed evidence for the event includes stratigraphic studies of tektites,Glass, B.P., 1978, Australasian Microtektites and the Stratigraphic Age of the Australites Bulletin of the Geological Society of America. v.
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Bolides that disintegrated in the Earth's atmosphere worldwide, 1994–2013 On September 7, 2015, at about 08:40 local time a bolide meteor appeared over Thailand and burned up approximately 100 km (62 mi) above the ground. The meteor briefly flared up producing a green and orange glow before disappearing without a sound of explosion and leaving a white smoke trail. The meteor was recorded by several dashcams during the morning rush hour in Bangkok, and sightings were also reported in Thai towns of Kanchanaburi and Nakhon Ratchasima. The meteor was visible for about four seconds before fading out.
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Typically, Taurids appear at a rate of about 5 per hour, moving slowly across the sky at about 28 kilometers per second (17 mi/s), or 100,800 km/h (65,000 mph). If larger than a pebble, these meteors may become bolides as bright as the Moon and leave behind smoke trails. Due to the gravitational perturbations of planets, especially Jupiter, the Taurids have spread out over time, allowing separate segments labeled the Northern Taurids (NTA) and Southern Taurids (STA) to become observable. The Southern Taurids are active from about September 10 to November 20, while the Northern Taurids are active from about October 20 to December 10.
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Other possible causes are related to the impact of one or more large bolides in northern hemisphere at Popigai, Toms Canyon and Chesapeake Bay. Improved correlation of northwest European successions to global events confirms the Grande Coupure as occurring in the earliest Oligocene, with a hiatus of about 350 millennia prior to the first record of post-Grande Coupure Asian immigrant taxa. An element of the paradigm of the Grande Coupure was the apparent extinction of all European primates at the Coupure. However, the 1999 discovery of a mouse-sized early Oligocene omomyid, reflecting the better survival chances of small mammals, undercut the Grand Coupure paradigm.
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When an asteroid enters the planet's atmosphere it becomes known as a 'meteor'; those that survive and fall to the Earth's surface are then called 'meteorites'. While basketball-sized meteors occur almost daily, and compact car-sized ones about yearly, they usually burn up or explode high above the Earth as bolides, (fireballs), often with little notice. During an average 24-hour period, the Earth sweeps through some 100 million particles of interplanetary dust and pieces of cosmic debris, only a very minor amount of which arrives on the ground as meteorites. The 1,200 meter-wide Meteor Crater in Arizona, United States, created by a 46 meter-diameter asteroid impact.
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The 60-tonne, long Hoba meteorite in Namibia is the largest known intact meteorite. A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the atmosphere to reach the surface of a planet or moon. When the original object enters the atmosphere, various factors such as friction, pressure, and chemical interactions with the atmospheric gases cause it to heat up and radiate energy. It then becomes a meteor and forms a fireball, also known as a shooting star or falling star; astronomers call the brightest examples "bolides".
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Major astronomical impact events have significantly shaped Earth's history, having been implicated in the formation of the Earth–Moon system, the origin of water on Earth, the evolutionary history of life, and several mass extinctions. Notable prehistorical impact events include the Chicxulub impact, 66 million years ago, believed to be the cause of the Cretaceous–Paleogene extinction event. The 37 million years old asteroid impact that caused Mistastin crater generated temperatures exceeding 2,370 °C, the highest known to have naturally occurred on the surface of the Earth. Throughout recorded history, hundreds of Earth impacts (and exploding bolides) have been reported, with some small fraction causing deaths, injuries, property damage, or other significant localised consequences.
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The cool early Earth (CEE) theory posits that for part of the Hadean geological eon, at the beginning of Earth's history, it had a modest influx of bolides and a cool climate, allowing the presence of liquid water. This would have been after the extreme conditions of Earth's earliest history between 4.6 and 4.4 billion years (Ga) ago, but before the Late Heavy Bombardment of 4.1 to 3.8 Ga ago. In 2002 John Valley et al. argued that detrital zircons found in Western Australia, dating to 4.0–4.4 Ga ago, were formed at relatively low temperatures, that meteorite impacts may have been less frequent than previously thought, and that Earth may have gone through long periods when liquid oceans and life were possible.
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In the near future, an unknown agent causes the Moon to shatter. As the pieces begin to collide with one another, astronomer and science popularizer "Doc" Dubois Harris calculates that Moon fragments will begin entering Earth's atmosphere, forming a white sky and blanketing the Earth within two years with what he calls a "Hard Rain" of bolides, causing the atmosphere to heat to incandescence and the oceans to boil away, rendering Earth uninhabitable for thousands of years. The world's leaders evacuate as many people and resources as possible to a swarm of "arklet" habitats called a "Cloud Ark" in orbit with International Space Station (ISS) bolted onto an iron Arjuna asteroid called Amalthea, which provides some protection against Moon debris. By the time the Hard Rain begins 701 days after the destruction of the Moon, approximately 1,500 people have been launched into orbit.
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When the meteoroids pass by Earth, some are accelerated (making wider orbits around the Sun), others are decelerated (making shorter orbits), resulting in gaps in the dust trail in the next return (like opening a curtain, with grains piling up at the beginning and end of the gap). Also, Jupiter's perturbation can change sections of the dust trail dramatically, especially for short period comets, when the grains approach the big planet at their furthest point along the orbit around the Sun, moving most slowly. As a result, the trail has a clumping, a braiding or a tangling of crescents, of each individual release of material. The third effect is that of radiation pressure which will push less massive particles into orbits further from the sun – while more massive objects (responsible for bolides or fireballs) will tend to be affected less by radiation pressure.
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