Geminids-Meteor Shower 2017
Geminids Meteor Shower
A meteor shower is a night sky event in which shooting stars (which is another term for meteors,) seem to radiate from a source point in the sky. The event is named after the constellation from which the meteors seem to radiate. Meteor showers are most commonly caused by the leftovers of a visiting comet, but they can also be caused by objects such as an asteroid. Geminids is a night sky event that is caused by 3200 Phaethon-Palladian asteroid. Geminids and the Quadrantis are the only meteor showers whose meteors are not originated by a comet.
This is a space event in which rocks or meteoroids from a comet come in contact with the atmosphere. The earth, in its orbit around the sun, encounters these types of rocks in space each year. When this occurs the meteoroids fly across the atmosphere, finding resistance and becoming incandescent. The meteors are known as shooting stars due to the paths they seem to follow in the night sky.
The rocky debris that makes this event occur are the leftovers of a comet that has traveled periodically around the sun. The heat of the sun sublimates the comet`s ice, producing a coma and long tail composed of rock, ice, and dust that is spread out on the path of the comet. Each comet visiting the earth has left its own debris and each source of meteoroids gives name to distinct meteor showers, including the Arietids, Orionids, Perseids, Geminids, to name a few. The name with which they are known is due to the constellation from which they seem to radiate.
Meteor Shower Radiant
Geminids Meteor Shower
The shooting stars of the Geminids are known for its intensity. The night sky event can be viewed during the first two weeks of December and it reaches its highest activity in the night of December 13-14, anywhere from 120-160 meteors can be observed during the late and early hours of these two nights. If the sky is clear, the viewing of up to a hundred meteors is guaranteed. The Moon will be in its waning crescent phase, showing 16% of its illuminated surface and will not interfere much with visibility.
The streaks of light from this shower are the remnants of 3200 Phaethon, which is thought to be an extinct comet-the rocky leftover of a comet that lost all of its ice after having orbited several times around the sun. The earth crosses this rocky debris each year in December, encountering the meteors that seem to originate in the direction of the constellation Gemini. The Geminids is one of the most prolific meteor showers of the year, with around 120 meteors per hour at the time of its highest peak if the sky conditions are clear.
Geminids-Visible in the Northern Hemisphere
The Geminids can be viewed in Both the southern and northern hemisphere; however, due that Gemini is a northern constellation, the best viewing is for those living north of the equator. Gemini occupies an area of 514 square degrees and lies in quadrant (NQ2) and is observable at latitudes between +90° and-60°. Constellations that can be seen near Gemini, include, Canis Minor, Cancer, Lynx, Auriga, Orion, Monoceros and Taurus.
Asteroid 2300 Phaethon
This is an asteroid with an orbit that resembles that of any comet. Possessing an orbital inclination of 22°, it´s the only asteroid that travels closer to the sun. With a semi major axis of 1.25 astronomical units (AU)-greater than that of earth´s, it is classified as an Apollo asteroid. The closest distance at which it approaches the sun is 1.26 AU, closer than any other asteroid, reaching a surface temperature of over 1000° K (750° C). It completes an orbit around the sun in 523.5 days or 1.4 years.
Based on Phaethon´s orbit, it´s most often referred to as a rock comet rather than an asteroid. It´s composed of dust and rock. Although, Phaethon is a rocky body, it has been detected ejecting dust. Other objects have been discovered exhibiting asteroid and comet characteristics. It was discovered in 1983 and shortly after that; it was observed that its orbital characteristics matched those of the Geminids Meteor Shower. It´s believed that this asteroid may have collided with another object, producing the stream of particles that the earth encounters every year.
Locating the Geminids in the Night Sky
The Geminids meteor shower is associated with the constellation Gemini, which is visible high in the sky during December. The most prominent stars in Gemini are Castor and Pollux. Since the meteors seem to come from Gemini, it´s said that the radiant is in Gemini, more exactly near the star Castor Gemini is the third constellation of the zodiac and it lies in the plane of the ecliptic-the imaginary line where the sun, moon and planets transit.
In the northern hemisphere, Gemini is located in the northeast horizon. It´s visible in the northeast of Orion, the hunter. If you spot the constellation Orion, which it´s recognizable for three stars that form its belt; just below this three stars lies Rigel-Orion´s foot and above them lies Betelgeuse-Orion´s shoulder. An imaginary line starting at Rigel and crossing Betelgeuse point directly to the stars Castor and Pollux. Another way to locate Gemini is using the Big Dipper, which is a circumpolar constellation and is visible throughout the year in the night sky.
The Big Dipper is a circumpolar asterism that is visible all night at regions above 40° latitude. Below this latitude, you’ll need to wait for it to rise on the horizon. The Big dipper looks like a kite, with four stars giving form to the kite and three stars being the string. This asterism is also known as the bowl; with Megrez, Dubhe, Phecda and Merak as the bowl and Alkaid, Mizar and Alioth as the handle. Drawing an imaginary line starting at Megrez and intersecting Merak will lead to the stars Castor and Pollux.
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When to View the Geminids
Meteors can be observed from December 9-16-although the best viewing is during the peak time which occurs on the nights of December 13-14. As usual, the best viewing occurs after midnight and before sunrise, most commonly at 2:00 A.m. As Gemini reaches its highest position in the night sky, the more meteors one will be able to observe. It´s recommended looking not directly into the radiant, but away from it, as meteors appear as streaks of light across the earth´s atmosphere.
Another option for best viewing is to travel away from the city or find a place that is not light polluted. Always try to arrive with minutes of anticipation and let your eyes adapt to the dark. You will be able to see more meteors if you place you gaze slightly away from the radiant. Also try to lie yourself on the ground looking upward; it´s comfortable and will let you cover more of the night sky.
© 2017 Jose Juan Gutierrez