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Presented to:Madam Nusrat
Presented by: Muhammad AzazRoll no#1811BS honors 5th semester
Department of Geography GCUF
Contents Eclipse History of eclipse Types of eclipse Eclipse duration Asteroids Comets Meteorites Black hole
History of eclipse
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Chinese astrologers wrote of an eclipse occurring over 4000 years ago.
Historians and astronomers believe that this was an eclipse that happened on 22 October 2134 B.C.
Two astrologers at the time, Hsi and Ho, had apparently failed to predict this eclipse, and so were beheaded.
Types of Eclipse
There are two types of eclipse
I.Lunar eclipse
II.Solar eclipse
Lunar EclipseWhen the Moon is in the full moon position, the light from the Sun may be blocked by the Earth which casts a shadow. As the Moon travels into the shadow it is gradually covered.
If you are in the umbra of the shadow, you will see a total eclipse.If you are in the penumbra of the shadow, you will have a partial eclipse
Types of Lunar EclipsesTotal Lunar Eclipse – when the Moon passes completely into the Umbra, or total shadow of the Earth.
Partial Lunar Eclipse – Occur when the Moon does not fully move into the Umbra.
Penumbral Lunar Eclipse – When the moon passes only through the penumbra, or partial shadow. They are barely visible.
Total Lunar Eclipse when the Moon passes completely into the Umbra, or total shadow of the Earth.
Eclipse Duration
• Longest total eclipse – 7:31 m:ss
• Longest annular eclipse – 12:30
• Longest eclipses in the 20th century – 3– June 1937 – 7:04– June 1955 – 7:08– June 1973 – 7:04
• Number of total eclipses longer than 7 minutes in the 21st century – 0
This is an animation showing a total lunar eclipse from startTo finish.
Solar eclipse Solar Eclipse- When the Moon casts a shadow on the Earth, causing the sun to go dark. The Moon comes between the Sun and Earth and casts a shadow on part of Earth.
Here is an animation showing a total solar eclipse
Remember that it is not safe to stare at a solar eclipse !!!
This animation shows that the moon creates a small shadow whichOnly allows certain areas of the earth to see a total solar eclipse.
Asteroids, the meteorites and comets
Asteroids An asteroid is a small planetary body that
revolves around the sun. (as minor planets or planetoids)
There are two main types of asteroids; one is grouped as dominating the outer area of the belt and being rich in carbon. The other is found in the inner part of the belt and composed mostly of melted minerals.
Asteroids vary in size from as big as 933km (Ceres) to only 6m in diameter.
Asteroid location Asteroids circle around the Sun
in orbits that trace their
origins in the Solar System.
Near-Earth Objects
Different typesBy studying both the brightness and the reflectivity of certain colours it becomes clear that asteroids fall into several different groups.
M are believed to be metallic
C are thought to be carbonaceous
S contain more silicates
Asteroid Sizes
Impact's of Asteroids In space On the earth surface 26 very large asteroids have been
discovered, which is probably most of the big ones.
But there are still millions of smaller ones that we have yet to see because they are too tiny, only a mile or so across.
12 space satellites are destroyed by the collision of asteroid which is a huge lose for their owner countries
Mass Extinction ImpactMass Extinction Impact
Barringer Crater in Arizona
It is 1.2 kilometers across and 200 meters deep, and was formed about 49,000 years ago by the impact of a 50 meter nickel/iron meteorite traveling at a speed of 11 kilometers per second.
Asteroid impact on earth
Asteroid about 10km in diameter approaches Earth
Comets A comet is an icy body that releases
particles of gas and dust. It contains a solid core made of ice
and rock surrounded by a cloudy coma and one or two tails.
Scientists believe there are two places where comets come from. Short-term comets come from the Kuiper belt beyond Pluto and long-term comets come from the Oort cloud.
Comets lose ice and dust while they travel leaving debris behind.
Differences of Comets and Asteroids
• Comets are made of ice and rock as well as dust particles.
• Asteroids are made of either carbon or melted minerals
• Comets have a core or nucleus, a coma and a tail
• Asteroids are just one whole part.• Comets come from the Oort cloud and
the Kuiper belt.• Asteroids come from the asteroid belt• Comets are very large; comas can be
1.6 million km and tails have been known to extend to 160million km
• Asteroids are usually under 1000kms in diameter.
Meteoroids
Small pieces of space debris (usually parts of comets or asteroids) that are on a collision course with the Earth are called meteoroids.
When meteoroids enter the Earth's atmosphere they are called meteors.
If the meteors survive and strike the surface of the Earth they are called meteorites.
Formation of Meteorites Most meteorites come from
the asteroid belt. This is a region between
Mars and Jupiter that contains many rock fragments broken off from asteroids.
There are 31,000 meteorites that we know about and all but 139 came from here.
Non-asteroid meteorites A small number of meteorites are made from
particles from other planets. They are known as non-asteroid meteorites.
A small number of non-asteroid meteorites come from the moon.
Several hundred tons of meteoroids enter the Earth's atmosphere each day. Most of these are very small pieces (milligrams) that burn up quickly in the atmosphere and never reach the surface.
Examples of meteorites fallThe first human we know to be hit
by a meteorite is Ann Hodges who lived in Alabama, USA. In 1954
The oldest report is from 1911 in Egypt when a dog was said to have been killed by a Martian meteorite.
The Barwell meteorite was the biggest to fall over Britain. It broke up and fell as a shower of stones over the village of Barwell on Christmas eve, 1965.
The Barwell meteorite, the biggest meteorite to fall on Britain.
Black hole Black hole is a very
powerful gravity that can grab a tiniest or the largest thing.
A black hole is a region in which gravitational field is so powerful than anything else
Light can also not escape from their gravitational force.
Location of Black hole Black hole are in
between of each galaxies, there are millions to billions black hole in the space.
Black hole grabs nearby stars. Because of black hole the galaxies are made.
Cygnus X-1