Seeing the invisible

If you can’t actually observe an astronomical phenomenon it is very difficult to explain it.

Here you will find a video we have created that brings together many science concepts that can’t be observed and looks at how we can begin to explain them.

Here is a list of useful scientific phenomena linked to space and physics covered in the video:

• Meteorites are rocks that fall to Earth from space. They come from the asteroid belt and some of them contain iron which makes them magnetic.
• The Sun is an active ball of gas – mainly hydrogen and helium. Over one million Earths could fit inside the Sun.
• The Sun ejects a stream of high energy particles called the solar wind. These particles can move at speeds reaching 750 kilometres per second!
• The solar wind interacts with the Earth’s invisible magnetic field. The magnetic field lines channel these particles towards the north and south poles, a bit like a bicycle getting caught in tram lines on the road and following the track.
• The air is made of a number of different gases such as nitrogen (78%) and oxygen (21%).
• These gases are usually invisible to us, however the solar wind particles collide with these gases, give them energy and in response they glow.
• These curtains of green, pink and red light are called aurorae, or the northern and southern lights.
• Some other planets such as Saturn and Jupiter have aurorae over their poles
• Aurorae also emit ultraviolet light which is invisible to our eyes. Astronomers use special telescopes that can detect this type of light.

If you would like to follow this up with extra activities take a look at the classroom resource How do we see things?