A spectacular
meteor shower lit up the skies last night with 100 shooting stars an hour as
the celestial firework display reached its fiery peak.
Gazing the star-studded sky is interesting ~ an ordinary daily event for
those who still live in villages – not for those of us, who live in small
apartments, where every wall, ground, roof and other space is shared with
people. At city, you will have more
difficulty due to ‘city light refraction’…… and on somedays you could suddenly
see ‘something lighting the sky’ 0r ‘falling objects leaving a trail’.
விண்வீழ்கல் என்பது
ஒப்பீட்டளவில் சிறிய, பூமிக்கு வெளியிலிருந்து, பூமியின் மேற்பரப்பை அடையும் பொருளாகும்.
விண்வெளியில் இருக்கும்போது இது விண்கல் என அழைக்கப்படுகிறது. A meteor or "shooting star" is the
passage of a meteoroid into the Earth's
atmosphere, incandescent from air friction and shedding glowing material in its
wake sufficiently to create a visible streak of light. 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. The
falling objects in many traditions are held to be a bad omen.
The Geminids are a
meteor shower caused by the object 3200 Phaethon, which is thought to be a
Palladian asteroid with a "rock comet" orbit. This would make the
Geminids, together with the Quadrantids, the only major meteor showers not
originating from a comet. The meteors from this shower are slow moving, can be
seen in December and usually peak around December 13–14, with the date of
highest intensity being the morning of December 14. The shower is thought to be
intensifying every year and recent showers have seen 120–160 meteors per hour
under optimal conditions. Geminids are debris from an extinct comet called 3200
Phaethon, which was previously believed to be an asteroid, according to NASA. The
meteors in this shower appear to come from a radiant in the constellation
Gemini (hence the shower's name). However, they can appear almost anywhere in the
night sky, and often appear yellowish in hue.
Across the globe,
the Geminids show is popular and is viewed by many during mid-December, not
sure whether it is so well visible over here. Pieces of gravel and dust
from "rock comet" called 3200
Phaethon shot across the sky and lit up discussion boards from NASA.gov to
Twitter — for those who could tear their eyes away long enough to type. In UK, Daily Mail reports that sky-watchers
braved freezing temperatures last night to enjoy the Geminid meteor shower in
clear conditions. It was visible in both
hemispheres and was spotted from Dover in Kent to Macedonia and across the
whole of the US.
Geminids are
classed as potentially hazardous, as they pass within 4.6 million miles of
Earth, burning 24 miles away. At their height, the Geminids produce between 50
and 100 shooting stars which travel at 22 miles per second. The report mentions of shooting stars seen
streaking across the night sky just after midnight in London and past the Dover
Patrol Memorial in St Margarets Bay, Kent. The best time to see the meteors was
around 2am, when the point in the sky from which the meteors appear to
originate - was almost overhead, next to the constellation Gemini. NASA map depicted how 556 fiery asteroids smashed into the
Earth's atmosphere in the past two decades... but most were harmless. 'Basically
it is the rocky skeleton of a comet that lost its ice after too many close
encounters with the sun,' NASA said on its website. But it has an eccentric
orbit that looks more like that of a comet than an asteroid and brings it well
inside the orbit of Mercury, the closest planet to the Sun, every 1.4 years. Traditionally
asteroids are made of rock and comets mostly of ice, but NASA describes
Geminids as a type of 'rock comet'.
Another unusual
feature of the Geminids is that they can shine in different colours. Mostly
glowing white, they may also appear yellow, blue, green or red. Regardless of
whether 3200 Phaethon is an asteroid or comet, it is classified as a
'potentially hazardous' near-Earth object (NEO). To be classified as
potentially hazardous, an NEO must pass within 4.6 million miles of the Earth.
At its closest upcoming approach on December 14 2093, the object will be
1,812,640 miles away - quite far enough to be safe.
Though some aspects of this newsitem was not so easily
comprehensible, the photos makes it an
interesting spectre.
With regards – S.
Sampathkumar
15th Dec
2014.
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