DISCOVERIES IN ASTRONOMY

 Astronomy is that part of  science that studies outer space focusing on stars, planets, comets, galaxies and so on.

We know that people started to study Astronomy as far back as in Ancient Mesopotamia. Civilizations such as Ancient Greeks, Romans or the Mayans also studied Astronomy. However all of these scientists had to observe space with just their eyes.

Aristotle, an ancient Greek astronomer, calculated that the Earth was not flat but a sphere. He observed that the Earth's shadow on the Moon was curved and that when a ship appeared on the horizon, we could see the top before the rest of the ship.

Copernicus was an astronomer that lived in the early 1500s. He came up with the idea that the Sun was the centre of the universe. This was a complete different believe from the idea that the Earth was the centre of the universe.

With the invention of the telescope in the early 1600s, scientists were able to see much further objects and were able also to have a better view of the Moon and the planets.

Galileo Galilei began to study Copernicus' work and felt that his observations of the planets were correct and that the Sun was the centre. This believe was really controversial at that time. Galileo heard of the invention of the telescope in Holland and he decided to build his own telescope. Soon Galileo's version of the telescope was used in all Europe. 

Galileo made many discoveries using his telescope: the four large moons around Jupiter and the phases of the planet Venus. He also discovered sunspots and that the Moon was covered with craters. As Galileo studied the planets and the Sun he became convinced that the Earth and the other planets orbited the Sun. However the powerful Catholic Church considered his ideas heresy. At first, they sentenced him to life prison but later on they allowed him to live in his house under house arrest.

Since Galileo's time many discoveries have happened and Astronomy has advanced a great deal.

 Men have landed on the Moon. We have great telescopes in the space to observe and investigate and since 2000 astronauts have lived on the International Space Station (ISS) that takes 92 minutes to orbit the Earth. Pedro Duque the first Spanish astronaut to go into space tells us about life in the ISS.

Finally, last year Nobel Prize in Physics 2019 was awarded to two astronomers Michel Mayor and Didier Queloz for discovering an exoplanet orbiting a star. That means that right now there are many astronomers looking for planets orbiting stars that have water, liquid water. This is fascinating, isn't it?