The Earth’s atmosphere is a layer of gases held close to its surface by gravity. It plays a crucial role in supporting plant and animal life, helps to maintain a global average surface ...
Explore this interactive diagram to learn more about the global carbon cycle.
Our world is made of elements and combinations of elements called compounds. An element is a pure substance made of atoms that are all of the same type. At present, 116 elements are known, and ...
Nitrogen is the most abundant element in our planet’s atmosphere. Approximately 78% of the atmosphere is made up of nitrogen gas (N2). Rights: Copyright 2013. University of Waikato. All rights ...
Fire is the visible effect of the process of combustion – a special type of chemical reaction. It occurs between oxygen in the air and some sort of fuel. The products from the chemical reaction ...
An interactive showing the main components of the terrestrial nitrogen cycle. Select one of the buttons to find out more.
Fires behave differently. Some burn slowly and evenly; others are extremely hot, burning fiercely and quickly. Different fires have different coloured flames. Some fires start easily; others don’ ...
Although elements such as gold, silver, tin, copper, lead and mercury have been known since earliest times, the first scientific discovery of an element occurred around 1669. Hennig Brand, a ...
This interactive looks at the electromagnetic spectrum. To use this interactive, move your mouse or finger over any of the labelled boxes and select to obtain more information. Select here for a ...
Elements are formed deep within the cores of certain types of star. Find out more in this interactive.
There are many interacting systems that make up the Earth, many of which are dynamic. These notes discuss the importance of understanding the concept of systems with emphasis on the water cycle ...
What is smoke and why do some fires seem to have more smoke than others? Smoke is a collection of tiny solid, liquid and gas particles. Although smoke can contain hundreds of different chemicals ...
Lightning is a large-scale natural spark discharge that occurs within the atmosphere or between the atmosphere and the Earth’s surface. On discharge, a highly electrically conductive plasma ...
Water in the Earth system is influencing all aspects of life on Earth. Pathways, storage, transfers and transformations have an effect on the global climate and human welfare. Within this ...
Looking down at the Earth from space, you can get an idea of just how much water there is. In fact, around 71% of the Earth’s surface is covered in water. Oceans make up about 97% of the world’s ...
Use this timeline to explore how humans have relied on fossil fuels in the past and how we are looking for, and using, new energy sources. 200,000 BC – Fire used Records of the first controlled ...
The universe is full of amazing things, but we need help to see most of them. There are many types of light that our eyes cannot see, so we use instruments, such as telescopes, that can detect ...
Water density changes with temperature and salinity. Density is measured as mass (g) per unit of volume (cm³). Water is densest at 3.98C and is least dense at 0C (freezing point). Why does ice ...
We happily live in the Earth’s gaseous lower atmosphere composed of a mixture of gases – primarily nitrogen and oxygen. However, if we move upwards from the Earth’s surface, the environment ...
Although the Moon appears to change during the lunar month, it is always the same shape. What does change is how much of the Moon we see from Earth, due to light and shadow. Points for ...
Dr David Krofcheck is a particle physicist who believes that the Big Bang is how matter came about. In this video, David explains how the universe as we know it came about – the Big Bang produced ...
Energy comes from many sources, and to describe these sources we use two terms: renewable and non-renewable. Non-renewable energy resources cannot be replaced – once they are used up, they will ...
Historical artefacts like moa bones can be dated using a technique that measures the activity of the radioisotope carbon-14 still present in the sample. By comparing this with a modern standard ...
Solar energy is transformed into other energy forms for our use on Earth – energy for food (chemical energy), electrical energy and heat energy. Food Solar energy (sunlight) is crucial for our ...
