If it had not entered at such a grazing angle, this meteoroid would have lost all its velocity in the upper atmosphere, possibly ending in an airburst, and any remnant would have fallen at terminal velocity. Its velocity was reduced by about 800 metres per second (2,600 ft/s) and the encounter significantly changed its orbital inclination from 15 degrees to 7 degrees. The object was tracked by military surveillance systems and sufficient data obtained to determine its orbit both before and after its 100-second passage through Earth's atmosphere. In 1994, Czech astronomer Zdeněk Ceplecha reanalysed the data and suggested the passage would have reduced the asteroid's mass to about a third or half of its original mass (reducing its diameter to 2–10 metres (6.6–32.8 ft)). Other sources identified it as an Apollo asteroid in an Earth-crossing orbit that would make a subsequent close approach to Earth in August 1997. Īnalysis of its appearance and trajectory showed the object was about 3–14 m (10–45 ft) in diameter, depending on whether it was a comet made of ice or a stony and therefore denser asteroid. However IAU's website states that these "suggestions have not been substantiated". The atmospheric pass modified the object's mass and orbit around the Sun, but it is probably still in an Earth-crossing orbit and is thought to have passed close to Earth again in August 1997. The smoke trail lingered in the atmosphere for several minutes. An eyewitness to the event, located in Missoula, Montana, saw the object pass directly overhead and heard a double sonic boom. It was seen by many people and recorded on film and by space-borne sensors. It entered Earth's atmosphere at a speed of 15 kilometres per second (9.3 mi/s) in daylight over Utah, United States (14:30 local time) and passed northwards leaving the atmosphere over Alberta, Canada.
The Great Daylight Fireball (a.k.a US19720810 and the Grand Teton Meteor ) was an Earth-grazing fireball that passed within 57 kilometres (35 mi 187,000 ft) of Earth's surface at 20:29 UTC on August 10, 1972. Material Component: A tiny ball of bat guano and sulfur.(Credit & Copyright: Antarctic search for meteorites program, Case Western Reserve University, James M. If the damage caused to an interposing barrier shatters or breaks through it, the fireball may continue beyond the barrier if the area permits otherwise it stops at the barrier just as any other spell effect does. It can melt metals with low melting points, such as lead, gold, copper, silver, and bronze. The fireball sets fire to combustibles and damages objects in the area. If you attempt to send the bead through a narrow passage, such as through an arrow slit, you must "hit" the opening with a ranged touch attack, or else the bead strikes the barrier and detonates prematurely. (An early impact results in an early detonation). A glowing, pea-sized bead streaks from the pointing digit and, unless it impacts upon a material body or solid barrier prior to attaining the prescribed range, blossoms into the fireball at that point. You point your finger and determine the range (distance and height) at which the fireball is to burst. The explosion creates almost no pressure. Unattended objects also take this damage. A fireball spell is an explosion of flame that detonates with a low roar and deals 1d6 points of fire damage per caster level (maximum 10d6) to every creature within the area.
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