Minggu, 01 Februari 2015

NATURAL PHENOMENON : SHOOTING STAR



Hello guys, today I will tell you about shooting star. I think It’s not strange again yeah, so let’s we check It guys!


Shooting star? What is it? maybe someone that didn’t know think that it is a phenomenon when a star fall to the earth, but No! It’s a false statement. Star is a luminous sphere of plasma held together by its own gravity and It is very big, the diameter is 40 km until 900.000.000 km, It’s very big right? For your Information, Sun is the one of star too. So, because It’s bigger than earth, If it fall down, the earth will broken.

So, what is shooting star, shooting star is the phenomenon when an object from a space that usually we call meteorid fall down to the earth, a meteoroid is a small rocky or metallic body travelling through space. 

Meteoroids are significantly smaller than asteroids, and range in size from small grains to 1 meter-wide objects. Smaller objects than this are classified as micrometeoroids or space dust. Most are fragments from comets or asteroids, while others are collision impact debris ejected from bodies such as the Moon or Mars


When such an object enters the Earth's atmosphere at a speed typically in excess of 20 km/s, aerodynamic heating produces a streak of light, both from the glowing object and the trail of glowing particles that it leaves in its wake. Ya! This phenomenon that we call “Shooting star” or “Falling star” or “Meteor”.

A meteor or "shooting star" is the passage of a meteoroid or micrometeoroid into the Earth's atmosphere, incandescent from air friction and shedding glowing material in its wake sufficiently to create a visible streak of light. Meteors typically occur in the mesosphere at altitudes between 76 to 100 km (47 to 62 mi) The root word meteor comes from the Greek meteĊros, meaning "high in the air." 



Millions of meteors occur in the Earth's atmosphere daily. Most meteoroids that cause meteors are about the size of a grain of sand. Meteors may occur in showers, which arise when the Earth passes through a stream of debris left by a comet, or as "random" or "sporadic" meteors, not associated with a specific stream of space debris. A number of specific meteors have been observed, largely by members of the public and largely by accident, but with enough detail that orbits of the meteoroids producing the meteors have been calculated. All of the orbits passed through the asteroid belt. The atmospheric velocities of meteors result from the movement of Earth around the Sun at about 30 km/s (18 miles/second), the orbital speeds of meteoroids, and the gravity well of Earth

History
Although meteors have been known since ancient times, they were not known to be an astronomical phenomenon until early in the 19th century. Prior to that, they were seen in the West as an atmospheric phenomenon, like lightning, and were not connected with strange stories of rocks falling from the sky. 

 Thomas Jefferson wrote "I would more easily believe that (a) Yankee professor would lie than that stones would fall from heaven." He was referring to Yale chemistry professor Benjamin Silliman's investigation of an 1807 meteorite that fell in Weston, Connecticut. Silliman believed the meteor had a cosmic origin, but meteors did not attract much attention from astronomers until the spectacular meteor storm of November 1833. People all across the eastern United States saw thousands of meteors, radiating from a single point in the sky. Astute observers noticed that the radiant, as the point is now called, moved with the stars, staying in the constellation Leo. 

The astronomer Denison Olmsted made an extensive study of this storm, and concluded it had a cosmic origin. After reviewing historical records, Heinrich Wilhelm Matthias Olbers predicted the storm's return in 1867, which drew the attention of other astronomers to the phenomenon. Hubert A. Newton's more thorough historical work led to a refined prediction of 1866, which proved to be correct. With Giovanni Schiaparelli's success in connecting the Leonids (as they are now called) with comet Tempel-Tuttle, the cosmic origin of meteors was now firmly established. Still, they remain an atmospheric phenomenon, and retain their name "meteor" from the Greek word for "atmospheric".



Notable meteors
1992—Peekskill, New York
The Peekskill Meteorite was filmed on October 9, 1992 by at least 16 independent videographers. Eyewitness accounts indicate the fireball entry of the Peekskill meteorite started over West Virginia at 23:48 UT (±1 min). The fireball, which traveled in a northeasterly direction, had a pronounced greenish colour, and attained an estimated peak visual magnitude of −13. During a luminous flight time that exceeded 40 seconds the fireball covered a ground path of some 700 to 800 km. One meteorite recovered at Peekskill, New York, for which the event and object gained their name, had a mass of 12.4 kg (27 lb) and was subsequently identified as an H6 monomict breccia meteorite. The video record suggests that the Peekskill meteorite had several companions over a wide area. The companions are unlikely to be recovered in the hilly, wooded terrain in the vicinity of Peekskill.
2009—Bone, Indonesia
A large fireball was observed in the skies near Bone, Indonesia on October 8, 2009. This was thought to be caused by an asteroid approximately 10 meters in diameter. The fireball contained an estimated energy of 50 kilotons of TNT, or about twice the Nagasaki atomic bomb. No injuries were reported. 
Bone, 08-11-09

2009—Southwestern US
A large bolide was reported on 18 November 2009 over southeastern California, northern Arizona, Utah, Wyoming, Idaho and Colorado. At 00:07 local time a security camera at the high altitude W. L. Eccles Observatory (2930 m above sea level) recorded a movie of the passage of the object to the north. Of particular note in this video is the spherical "ghost" image slightly trailing the main object (this is likely a lens reflection of the intense fireball), and the bright fireball explosion associated with the breakup of a substantial fraction of the object. An object trail can be seen to continue northward after the bright fireball event. The shock from the final breakup triggered seven seismological stations in northern Utah; a timing fit to the seismic data yielded a terminal location of the object at 40.286 N, -113.191 W, altitude 27 km. This is above the Dugway Proving Grounds, a closed Army testing base.
2013—Chelyabinsk Oblast, Russia
Over 1,500 people were injured mostly by glass from shattered windows caused by a meteoroid explosion during meteor event in Chelyabinsk Oblast, Russia on 15 February 2013, when a meteoroid exploded approx 25 to 30 km above the environs of Chelyabinsk, Russia. An increasingly bright streak was observed during morning daylight with a large contrail lingering behind. At no less than 1 minute and up to at least 3 minutes after the object peaked in intensity (depending on distance from trail), a large concussive blast was heard that shattered windows and set-off car alarms, which was followed by a number of smaller explosions. Scientists at NASA's Jet Propulsion Laboratory (JPL) estimated the meteoroid to have an initial mass of 11,000 tonnes, and to measure approximately 17 to 20 metres across, as it entered the earth's atmosphere.

MITOLOGY OF STARSHOOT
Because they are so sudden and short-lived, shooting stars inspire many myths about wishing and omens. Nowadays, When there are a starshoot, people will pray cause they believe that  when It’s happen, god will hear your pray and your wish will be granted, but Is it true? In my belief, god will always hear our pray, and It’s not related with star. It’s all about your belief and your faith:)

Traditionally, shooting stars were seen as omens of dangerous times for Europeans. Current myths about shooting stars revolve around making a wish when one is seen.

Although older myths about shooting stars generally held them as omens, modern myths are often more related to misunderstandings about science. Many people believe that meteors are large pieces of rock, maybe even big enough to kill a person or to destroy the earth. Actually, most meteors are no larger than specks of dust, and only the largest meteors even reach the ground.
Myths about shooting stars vary greatly around the world. In East Africa, some tribes consider them to be the manifestations of a deity, while others see them as bad omens. Native American tribes had a wide variety of beliefs about shooting stars, seeing them as war omens, as traveling spirits of shamans and heroes, and even as the feces of stars.
Most shooting-star myths are based on beliefs related to the observed phenomena. Meteors do look like stars shooting through the sky. Their sudden appearance can be startling, which may explain why shooting stars are so often seen as bad omens. Occasionally, pieces of meteor do reach the ground, leading people to think that all shooting stars leave debris.
Meteors as Omens

  • In Switzerland, a meteor was considered to possess the power of God.

  • Swabians believed that a shooting star presaged a year of good fortune, but if one saw three in one night, then he was doomed to die.
  •  In Chile, one must pick up a stone when sees a meteor.
  • In the Philippines, one must tie a knot in a handkerchief before the light is extinguished.
  •   Modern Hawaiian Japanese are reported to believe that if a meteor comes in your direction, you must open the collars of your kimono to admit the good luck.
  • In Baltic countries and central Europe, people believed that everyone had a personal star which fell upon his or her death. This led some to say such things as 'rest in peace' or 'may God guide you to a good path' upon seeing a meteor.
  • Pointing to a meteor or talking of a meteor was considered bad luck by some in America.
  • Among those who believed meteors signaled ill-omen, saying certain words could avert the bad luck--for example, 'amen,' 'God guide it,' or 'go away, go away, all by yourself.'
  •  Perhaps the most famous omen was that divined form the Ensisheim stony meteorite which fell in Alsace (now in France) in 1492. The Holy Roman Emperor Maximillian assembled his council to help determine the meaning of the fall. The council determined that it as a good omen in his wars with France and the Turks. 



There Is a video of a meteor that hits Rusia at 2013





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