My Science School

Christianity is a religion that has one God. Its followers — Christians — believe that Jesus Christ was the Son of God and that he lived to show people the way to eternal life with God through the forgive-ness of sins (wrongdoing). A key Christian belief is that Jesus was killed by his enemies and then rose from the dead to join God in heaven. Christianity is the world’s largest religion, with more followers than any other.

Christianity traces its beginning to the miraculous birth, adult ministry, death and resurrection of Jesus of Nazareth, known as Jesus Christ. Over 2000 years ago in Palestine (today's Israel), Jesus was born into a humble Jewish family. His mother was a young peasant woman named Mary.

Christians believe that his father was the Holy Spirit of God, making Jesus both fully human and fully divine. His earliest followers came to believe that he was the Messiah, or messenger, sent by God to free God’s people from slavery, sin, and death. God sent his son Jesus in human form so that people would better understand God as a caring and loving parent.

Jesus lived and experienced the suffering of humans. Jesus healed the sick and told stories, or parables, and preached sermons that taught what God wanted people to do – to love God with all their hearts and love their neighbors as themselves. Jesus taught by example. By being loving and forgiving himself, Jesus taught others to be loving and forgiving - especially toward those who were considered outcasts in society. This is the central message and style of Jesus' teaching.

During his adult ministry, Jesus built up a loyal following, led by his twelve disciples. But Jesus also made enemies among the religious and political leaders of his time. In the end, these powerful leaders were so threatened by Jesus' growing following that the Roman governor sentenced Jesus to death and had him crucified. The third day after Jesus’ death, his followers found his tomb empty and discovered that he had been raised from the dead. Christians believe that the painful sacrifice of Jesus' life on the cross shows how much God loves God's people. Jesus paid with his life on Earth for the sins of the world.

Christians believe that in raising Jesus’ from the dead, God showed that Jesus’ message of love and forgiveness was more powerful than death, and that believing in Jesus and following the example of his life and his teaching would lead to eternal life after death. The resurrection (rising from the dead) is the sign of God’s salvation offered to all people. 

After his resurrection, Jesus Christ’s followers spread his message throughout the world, creating the Christian Church. Today there are about two billion Christians living all over the world.

Picture credit: Google

Ancient Greece’s wisest scientists did not go along with the generally accepted thinking of their ancestors – that the Earth was a circular plate supported by four elephants standing on a huge sea turtle. They had already concluded that it was a sphere. The idea was mooted about 500 BC by followers of Pythagoras, who considered the sphere to be the perfect shape.

The first man to be credited with measuring the Earth’s circumferenace was the Greek astronomer Eratosthenes in 230 BC. He reasoned that if the Earth was a sphere, then the line joining two places was an arc of a great circle. If he could measure the distance as both a length and as a proportion of 360 degrees (a complete circle), he would have an arc from which he could calculate the total circumference.

It had been recorded that at noon at the summer solstice (about June 21), the Sun was directly overhead at Syene (modern Aswan) because it shone vertically down a deep well. So at the same time of year at Alexandria, many miles to the north-west of Syene, Eratosthenes measured the angle of the Sun from the vertical and found it was one-fiftieth of a complete circle – exactly 7.2 degrees in today’s measure.

He then need to know the crow’ flight distance between Syene and Alexandria. One of the ways in which he may have calculated this was by the journey time of camels. A laden camel keeps up a steady pace, and could travel at around 100 stadia a day – today 1 stade is usually regarded as about 605ft (185m). Since a camel caravan took 50 days to travel between Alexandria and Syene, Eratosthenes made the distance 5000 stadia – about 575 miles (925km). This produced the figure of 250,000 stadia, or roughly 28,740 miles (46,250km), as the circumference of the Earth.

Bearing n mind his lack of equipment and his rule of thumb measurements, it is remarkable that he arrived at a figure that is less than 15 per cent too long compared with modern measurements. Had he known the exact distance between Syene and Alexandria – 526 mile (847km) as the crow flies – his answer would have been just under 230,000 stadia, about 26,440 miles (42,550km), and only 6 per cent out.

Today, we know that the Earth is flattened at the North and South Poles, and the circumference at the Equator is about 24,900 miles (40,075km).

 

Picture Credit : Google  

Elephants were used in warfare mainly as a shock force – not only to scare the enemy but also like tanks, to push them aside. And they could carry small towers on their backs, from which marksmen could launch arrows or spears – although there is no evidence that Hannibal’s elephants carried them. On marches, elephants proved useful pack animals, being able to carry up to ten times more than a house. A disadvantage, though, was the amount of food needed – an elephant eats up to 300lb (140kg) pf vegetation a day. As the army climbed even higher and snow made grazing impossible, the elephants suffered severely from hunger.

Hannibal’s elephants were not very large, standing probably about 8ft (2.4m) at the shoulder. Hannibal captured them from the foothills of the Atlas Mountains of northern Africa, where elephants have become extinct since his day. Hannibal also had a few Indian elephants, which Carthage had obtained from Egypt.

That elephants were held in high esteem by the Carthaginians is evident from some of their silver coins, which feature them on the reverse. The fronts of the coins showed gods and important people, including Hannibal (above left).

 

Picture Credit : Google