Posted: 30 Aug 2010 07:24 AM PDT

London, Aug 30 : Dinosaurs may have been wiped out from the earth 65 million years ago by a meteor shower which lasted thousands of years, according to new evidences.

Scientists had identified a giant Chicxulub crater in the Gulf of Mexico as the site of a single meteor strike thought to have obliterated prehistoric life on earth.

But evidence for a second impact in Ukraine, dating back thousands of years before the Chicxulub impact, has raised the possibility that the dinosaurs may have been blitzed with a shower of meteorites, The Telegraph reported.

The Boltysh Crater in Ukraine was first discovered in 2002. But experts have unearthed a second cavity within the crater which they believe was caused by the aftermath of the Chicxulub impact - suggesting that the two meteor strikes occurred years apart as part of a wider "shower".

Scientists dated the two Boltysh impact zones by examining the pollen and spores of fossil plants in the layers of mud within.

Ferns are among the first plants to colonise a devastated landscape after a catastrophe, leaving layers of spores - dubbed "fern spikes" - which are considered good markers of past impact events.

The researchers found a second "fern spike" one meter above the first in the Boltysh crater - suggesting that two separate strikes occurred thousands of years apart.

"We interpret this second layer as the aftermath of the Chicxulub impact. It is quite possible that in the future we will find evidence for more impact events," said Simon Kelley of the Open University, who co-authored the study.

Monica Grady, a meteorite expert at the Open University, said the shower could have been caused by "the collision of Near Earth Objects".

The US space agency NASA has recently launched a programme "Spaceguard" which aims to monitor such Near Earth Objects as an early warning system of possible future collisions.

The new findings are published in the journal Geology by a team lead by Professor David Jolley of Aberdeen University.

--IANS

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Draconids Meteor Shower: 2010 Might Produce Anything - Associated Content

Posted: 24 Sep 2010 09:24 AM PDT

Draconids meteor shower will make its appearance October 7 and 8, 2010, when the Earth passes through the dust from the comet 21P/Giacobini-Zinner. Although this particular meteor shower may not present a

lot of meteor activity this year, it has been known to produce hundreds of meteors in an hour at times. The Draconids is best known for the meteor presentation of 1933, when more than 54,000 meteors streaked across the sky. It's been estimated there were over 6000 sent off each hour. Because it is always possible that we might get something exciting this year, I believe it is worth waiting for and watching.

How Draconids meteor shower got its name

The Draconids meteor shower makes its best presentation in the northern hemisphere. Its radiant point is nearly on top of the head of the constellation Draco the Dragon, and is highest in the northern sky as darkness approaches.

Can we expect more than a few streaks of light and blaze in 2010?

Most of the time, Draconids meteor shower sends just a few meteors an hour shooting through the sky. However, like any object in the universe, the only sure thing to expect is the unexpected. We might be treated to a steady stream of lights and flares. That is definitely worth waiting for.

Sky conditions

We are in luck with the Draconids meteor shower this year. The new moon is scheduled for October 7, promising darkened conditions for easy observation. One of the best parts is that activity occurs earlier in the evening, so no one has to stay up till after midnight to catch a glimpse or obtain a full view, of the meteor shower.

Locating the Draconids meteor shower

Look towards the north. The evenings of October 7 and 8 should present the opportunity to see these rather slow-moving, almost yellow meteors. Follow this link for an easy-to-read directional map. There may be activity on October 9, also, as the Earth moves on and leaves the Draconids behind till next year.

Go here for a list of other meteors scheduled for 2010.

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View the Lyrid Meteor Shower of 2011 - Associated Content

Posted: 24 Sep 2010 02:11 PM PDT

About the Lyrid Meteor Shower

The Lyrid Meteor Shower is named after the constellation Lyra, as the meteors appear to be falling from the constellation. The debris that forms the Lyrid shower is dust from the comet C/1861 G1, known as Thatcher.

This year, the Lyrid Meteor Shower will begin around April 16^th and will continue through April 26^th. The Lyrids will peak the night of April 21^st through the morning of the 22^nd. Other meteor showers, the Pi Puppids and Gamma Virginids will be active during the Lyrids peak, though you are unlikely to see anything from them unless you have a telescope as they are much smaller showers more suitable to expert astronomers.

The Lyrid shower typically produces between 10 and 20 meteors per hour. While this is a relatively small shower compared to other annual showers, it is still significant. The Lyrids tend to leave an obvious dust trail that will be visible for a few seconds. Also, in the past, the Lyrids have been known to suddenly produce up to 100 meteors in one hour. The reason for this is unknown. Whether or not the Lyrids will turn from a shower into a storm in not predicted; we will just have to watch and see.

Viewing the Lyrid Meteor Shower

In 2011, the peak of the Lyrid meteor shower around midnight on the 21^st of April. When the moon sets allowing a darker sky, more meteors will become visible. The best time for viewing them will be before the sun rises on the 22^nd. If you are able to view the shower from a "dark" area, you will see more meteors.

On April 22^nd, you should set up while facing east. Around 3:00am, the shower show will really begin, and you should look directly up. You will not need a telescope to view the shower, though if you have one you will be able to see more meteors and their trails in greater detail.

For a checklist of items to bring while viewing the Lyrids and how to stay safe while having fun, check out How to View Meteor Showers.

Source:

http://www.astronomy.com/asy/default.aspx?c=a&id=10115

http://stardate.org/nightsky/meteors/

http://www.theskyscrapers.org/meteors/

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Meteor

Sunday, September 26, 2010

“Dinosaurs wiped out by meteor shower lasting ages - New Kerala” plus 2 more

“Dinosaurs wiped out by meteor shower lasting ages - New Kerala” plus 2 more

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