The Strathmore Meteorite - A rare visitor from Space - Culture Perth and Kinross
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The Strathmore Meteorite A rare visitor from Space
WHAT ARE METEORITES?
Most meteorites are fragments of asteroids.
As they enter the earth's atmosphere they are seen as a bright
streak of light or fireball called a meteor. Most burn up in the
atmosphere and only those that land are meteorites.
The largest asteroid is Ceres about 950 km
in diameter. It has 25% of the mass of all
the other asteroids put together.
One of the next largest is Vespa between
400 and 525 km in diameter.
WHERE DO THEY COME FROM?
Most meteorites come from the asteroid belt between Mars and
Jupiter. The centre of the asteroid belt is about 251 million miles from
the sun.
Occasionally two asteroids hit each other and one is knocked out of
orbit and heads to earth.
A few meteorites come from the Moon or Mars. These are rocks that
have been blasted from the surface during the impact of a large
asteroid.HOW OLD ARE THEY?
Meteorites are remnants left over from the formation of the solar
system about 4.5 billion years ago.THERE ARE THREE TYPES OF METEORITE
1. Stony meteorites.
Stony meteorites contain small amounts of nickel-iron, but are
mostly made of minerals of silica.Stony meteorites are divided into chondrites and achondrites.
Chondrites are made of tiny spheres called chondrules. These were
molten mineral droplets formed during collisions of space debris
during the formation of the solar system.
Achondrites do not contain chondrules.
94% of observed falls are stony meteorites; Chondrites make up
about 86 % of all falls.2. Stony-iron meteorites
Stony-iron meteorites contain an equal mixture of silicate minerals
and nickel-iron alloy.
They are the rarest meteorites making up about 1-2% of falls.3. Iron meteorites
Iron meteorites are mostly made of contain nickel-iron and
probably most closely resemble the Earth’s core.
They account for about 5% of observed fallsWHAT CAN METEORITES TELL US?
Meteorites are the oldest rocks in the solar system, more than 4.5 billion years
old.
They contain information about the formation of our Sun and planets.
They contain the same minerals that are found on earth, but they have not been
changed by geological processes.
They can tell us about the internal structure of the earth.
Large meteorites can make craters on Earth and other planets.
A few meteorites contain water and organic compounds, so they may have
brought the building blocks of life to earth.METEOR SHOWERS Meteor showers are believed to be caused by debris from comets tails Name Date of Peak Moon Quadrantids night of January 3 Sets after midnight Lyrids night of April 21 New Eta Aquarids night of May 5 Full Perseids night of August 13 Morning crescent Orionids night of October 21 First quarter Leonids night of November 17 Evening crescent Geminids night of December 13 New
METEORITE FALLS
2235 meteorites are thought to land on Earth each year.
40,0000 tons of space debris land on earth each year.
21 meteorites or meteorite showers have been seen in the UK
between 1795 and 1999.Scottish Meteorites
It is estimated that approximately 6 meteorites land in Scotland per
year.
Three meteorite falls have been observed;
High Possil in 1804
Perth in 1830
Strathmore in 1917
Another meteorite was found in Glenrothes in 1998.
All of the Scottish meteorites recovered are stony chondrites.The meteor was seen as a bright fireball, even during the day,
leaving a trail of sparks behind it.
It was first seen from Hexham in Northumberland 203 Km (126
miles) away.
It travelled northwest across east Scotland.
It was seen from St Boswells in the Borders.
the Port of Menteith and Bridge of Allan in Stirlingshire.
Crossgates, Fife and even Aboyne in Aberdeenshire.
The meteorite exploded just west of Dundee at 1.15pm on 3rd
December 1917.The sound of the meteor passing overhead was heard in Dundee,
St Andrews, Forfar, Cottown and Burrelton.
We know so much because Henry Coates Curator of Perth Museum
at the time made extensive enquiries and took statements from
eyewitnesses of the event.Amongst the witnesses interviewed by Mr Coates
One heard a "Loud explosion lasting two minutes", followed by a
"humming sound like a small airplane".
A Mrs Miller from Burrelton close to the find sites saw “three fireballs”
A crane driver at Cottown quarry heard "several concussions" which
made the chains of his crane rattle.
Witnesses in Dundee heard an explosion, but thought it was due to
work in one of the local quarriesTHE RECOVERED STONES
Four meteorites were recovered in a line between South Corston
in Angus and Easter Essendy in Perth and Kinross.
The first stone that fell was at South Corston and weighed just
over a kilogram.
At Keithick the stone hit the roof of the south lodge and was found
later in the rafters. It also weighed just over a kilogram.
The Carsie specimen actually landed about 18 m (20 yards) from
Mrs Welsh It also weighed about a kilogram
At Easter Essendy the finder was guided to the spot where it fell
by the commotion caused amongst a flock of sheep who were
feeding in a field. It weighed about ten kilogramsWHAT HAPPENED NEXT?
According to Mr Coates “All four fragments were claimed by the Crown
Authorities and were sent to the Kings Remembrancer for Scotland. The
Director of the Royal Scottish Museum (now the National Museum of
Scotland) was instructed to select two of the fragments for that Institution,
and he chose the Essendy and Carsie fragments, as exhibiting the most
interesting and characteristic features”The remaining two fragments were returned to the finders, those being
Miss Mary Hill in the case of the Keithick Fragment, and Mr. Thomas
Buttar in the case of the Corston Fragment.
Eventually however the Corston fragment was donated to Perth Museum.
A small piece on display was cut off the Easter Essendy stone at the
National Museum of Scotland and sent for analysis to the Natural History
museum in London.The Strathmore meteorite is technically known as an L6 chondrite.
L for low iron content and six for the degree of damage to it’s’
chondrules.
This is thought to have occurred by melting caused when two
asteroids collided.
An analysis identified the most abundant compounds
40% silicon dioxide
26% Magnesium oxide
13% Iron oxide
6% Iron
1% NickelYou can also read
