Aurora Australis

Have you ever witnessed nature's light show dancing across the night sky? This colourful display is often referred to, and known as, the Southern lights. What causes this spectacular illumination, Aurora Australis?

The first thing that triggers an Aurora Australis is a solar flare. A solar flare is a gas wave that comes off the sun. There is another type of solar flare, it is  called a corona. The corona is a gigantic cloud of electrons, ions and atoms.

Earth has a magnetic field, the magnetic field acts like an invisible shield around the Earth. When all the atoms, ions and electrons hit the magnetic field they follow the path of the invisible shield and are guided to the North and South poles.

Ions accelerate after they hit the magnetic field and collide with other particles, they then release energy in the form of light.

The Aurora Australis is a beautiful thing to see. You can see the Aurora Australis at night at the South Pole.

Volcanoes

Have you ever witnessed the lava flow down the side of a volcano? Volcanoes are the most explosive land form. Ash is thrown into the air along with hot and poisonous gases, lava and rock flow down the volcano destroying everything in it’s path.

Tectonic plates are massive plates under the ground covering the whole of the Earth. When tectonic plates move out of place and then they form a rocky volcano. Volcanoes are also formed under the sea. Active volcanoes mostly occur on the plate boundaries.

Deep inside the Earth, between the crust and the mantle you will find magma. The magma will find an opening in the Earth's crust and squirt out magma in the form of lava. The speed of the lava flow depends on the thickness of the lava. Magma and lava are a little bit different because magma stays in the volcano and lava is the red hot liquid that comes through the volcanic vent and then out the crater with the hot and poisonous gasses.

There are many types of volcanoes. An active volcano can erupt at any time. A dormant volcano means that it hasn't erupted in a very long time but it will erupt again. An extinct volcano means that it will not ever erupt again.

Volcanoes can trigger other disasters such as flash floods and tsunamis which are normally the result of a volcano erupting under the water. An earthquake could also be triggered because the ground around the eruption point it is not stable.

Harry.B

On Monday 29 June, syndicate four had a showcase. There were some amazing presentations. There were some on space, eyes, chocolate, volcanoes and black holes. Here are some pictures from the showcase.