How Do Rainbows Form?
A rainbow forms when sunlight is bent, split and reflected inside raindrops, spreading white light into a band of colours. This guide…
Dr. Nadia Okoro
Science
Research, discovery and the natural world — from the cosmos to the cell.
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What Is a Galaxy?
A galaxy is an enormous, gravity-bound system of stars, gas, dust and dark matter. This guide explains what galaxies are made of, the main…
Dr. Nadia Okoro
How Does the Human Eye Work?
The eye works like a living camera, bending light onto a light-sensitive screen at the back and sending signals to the brain. This guide…
Dr. Nadia Okoro
How Do Solar Eclipses Happen?
A solar eclipse happens when the Moon passes directly between the Earth and the Sun, casting its shadow on our planet. Here is the geometry…
Dr. Nadia Okoro
What Are Tectonic Plates?
Tectonic plates are the giant slabs of rock that make up the Earth's outer shell, drifting slowly over the hot interior. Here is how they…
Dr. Nadia Okoro
What Is the Ozone Layer?
The ozone layer is a band of gas high in the atmosphere that absorbs most of the Sun's harmful ultraviolet radiation. Here is what it is…
Dr. Nadia Okoro
How Does GPS Work?
GPS pinpoints your location by timing radio signals from a fleet of satellites orbiting thousands of miles overhead. Here is the science of…
Dr. Nadia Okoro
How Do Clinical Trials Work?
Clinical trials are carefully designed studies that test whether a new treatment is safe and effective in people. Here is how they progress…
Dr. Nadia Okoro
Renewable vs Non-Renewable Energy
Renewable energy comes from sources that replenish naturally, while non-renewable energy comes from finite stocks that run down as we use…
Dr. Nadia Okoro