Science: Age 17

7 illustrated Science lessons for Age 17.

The Great Oxidation Event From about 2.4 billion years ago, cyanobacteria doing photosynthesis began releasing large amounts of oxygen i…
How planets orbit the Sun A planet travels around the Sun on an ellipse, and the Sun sits at one focus, not at the centre. The line from…
Ice cores, archives of ancient air As snow piles up on Antarctica and Greenland, it compresses into ice and seals off tiny pockets of the air abo…
Heat Trapped in the Air Sunlight reaches Earth's surface and warms it. The warmed surface emits infrared, and gases in the air absorb …
Ripple tank with two sources Two identical loudspeakers sit under the water surface and send out circular ripples at the same steady rate. …
Satellites Around Earth Satellites and planets move under gravity, which keeps them on curved orbits. Their distance from the central …
Elliptical Orbit Pull A satellite follows an ellipse because gravity always pulls it toward the planet at one focus. Its speed chang…