Cosmic dust in your eye

By JOHN DUNLOP

Getting up a couple of hours before dawn promises to be a rewarding pastime in the next week, with an impressive meteor display expected, especially for those looking northeast away from city lights.

There should be a bonus on Monday morning when there should be hundreds or even a thousand on show each hour.

Be out between 3 am and 5:30 am when it starts getting light, and make sure you have a good dark view to the northeast.

The meteors, so-called shooting stars, are cosmic dust, probably from some comet that left a trail of debris in our neighbourhood.

The bright flash is the dust slowing down from about 200,000 km/h to nearly a standstill in a few brief seconds.

All the energy of movement is converted to heat and light. It is a bit like bugs splatting themselves on the windscreen of a car.

Every day hundreds of tonnes of meteor dust settles on the Earth. Who knows, you might have had to rub a speck of cosmic from your eye!

The annual Leonid meteor shower will be active through until next Wednesday.

Meteors in the shower appear to come from the constellation Leo the lion, which rises in the northeast around 3 am at this time of the year.

The display is unlikely to match the great storms witnessed in 1833 and 1966 from the United States.

Abraham Lincoln was out there in 1833 and this is what the President had to say when some pessimistic businessmen accosted him: "When I was a young man in Illinois, I boarded for a time with a deacon of the Presbyterian church.

"One night I was roused from my sleep by a rap at the door and I heard the deacon's voice exclaiming, 'Arise, Abraham, the day of judgment has come!'

"I sprang from my bed and rushed to the window and saw the stars falling in great showers!

"But looking back of them in the heavens I saw all the grand old constellations with which I was so well acquainted, fixed and true in their places.

"Gentlemen, the world did not come to an end then, nor will the Union now."

The science of analysing meteor storms has advanced quite a bit in the past few years.

The meteors originate from comet Tempel-Tuttle, which orbits the Sun every 33 years, shedding dust and dirt as it goes.

David Asher from Armagh Observatory in Northern Ireland and Rob McNaught from the Australian National University, who have analysed data from previous observations, predict that we will see many more meteors than usual on Monday.

Of course those who are really lucky might see a bright fireball, or even a meteorite falling to earth.

These larger chunks of extraterrestrial junk are rather rare and more likely to originate from asteroids than comets.

Fewer than 10 meteorites are known to have fallen in New Zealand.

Giant meteorites a kilometre or more across are even more rare.

Their rarity is a good thing, because there is now good evidence available showing that they have extinguished most life on Earth several times during the past billion years.

* More information about meteors and meteorites is available at stardome.org.nz, or call in at the Auckland Observatory on One Tree Hill any day or Tuesday to Saturday nights to check out the meteorite display.