EnviroKids October 2018 Issue

World-class Facility in South Africa

Astronomy

Astronomy is the type of science that deals with celestial objects, space, and the physical uni verse. Many astronomers have contributed to our modern understanding of space. Galileo Galilei is called the "father of obser- vational astronomy” because of his many observations about space. He invented the thermoscope and various compasses. He also discovered and explored (through a telescope) the phases of Venus, Jupiter’s satellites, Saturn’s rings, and sun spots. Nicolaus Copernicus was a mathematician and astronomer who first assumed that the Sun (not the Earth), is at the centre of the universe. Nicolaus was a polyglot (knowing or using several languages) and a polymath (a person of wide knowledge or learning), and he also had a doctorate in canon law. Sir Isaac Newton was an English mathe- matician, astronomer, theologian, author and physicist, and is recognised as one of the most influential scientists of all time. He created the Laws of Motion and Uni- versal Gravitation. Newton built the first reflecting telescope and developed a theo- ry of colour based on the observation that a prism separates white light into what we see on the colour spectrum. He also made the first theoretical calculation of the speed of sound, and contributed greatly to the field of mathematics. Johannes Kepler was a German mathe- matician, astronomer, and astrologer. He is most known for his Laws of Planetary Motion, which served as the foundation for Sir Isaac Newton’s theory of Universal Gravitation. He also invented an improved version of the refracting telescope.

The South African Astronomical Observatory (SAAO) operates under the Department of Science and Technology. The main telescopes are used for research and are located at the SAAO observation station 15km from Sutherland in the Northern Cape. SAAO's primary function is to conduct research in astronomy and astrophysics and does so by providing a world-class facility to scientists.

Tech in Space

From floating objects, to robots on Mars, our technology is starting to take over in space.

A Rocket is a spacecraft that obtains thrust from a rocket engine. Rockets weigh hundreds of tonnes at lift-off, most of which is fuel. Rockets need an immense amount of fuel to overcome Earth’s gravity. Only when they reach a speed of 28 000 km/h are they travel- ling fast enough to enter orbit. Most rockets are made up of a few stages. When a stage has used up all of its fuel, it is separated to get rid of the dead weight.

The Mars Rover is a self-propelling vehicle used to explore the surface of Mars in temperatures and conditions that humans cannot survive. Rovers examine new territories via remote control. There have been four successful robotically operated Mars rovers. In January 2016, NASA reported that the Curiosity and Opportunity rovers will be searching for evidence of ancient life on Mars, including biospheres as well as remnants of water, to assess whether Mars was ever habitable.

A Satellite is an object that orbits a planet, and the first artificial satellite to orbit Earth was Sput- nik 1, which was the size of a beach ball. Satellites are used for various reasons, including for GPS purpos- es (Global Positioning System), telecommunications, weather monitoring, and scientific research. Satellites are made of various light-weight components that allow it to work in the harsh climates of space. One such component is the ‘wings’, which are made of so- lar panels that power the satellite using energy from the Sun.

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