Great Moments In Science

Vaccines are not a new invention. One of the very first effective vaccinations against disease came from China about 1,500 years ago - and was widely used there to combat Smallpox.

Today’s technology has given us an avalanche of information about how, and where, animals travel. We have radar, motion-activated cameras, drones, DNA sequencing, as well as battery-powered geo-location devices that are light enough to be carried by butterfly, but powerful enough to send their data to orbiting satellites.

Our modern periodic table has 118 known chemical elements. About 94 of them occur naturally and the rest were manufactured by us. An element is a pure substance made of atoms that have the same numbers of protons in their central nucleus. What does an atom look like, and where are these protons?

Dr Karl still has more to tell us about the first known computer - this week it's Part 3. After its discovery it took a little while to clean up - and for the conservators to see what was on the inside. They still didn't know what it was meant to do.

Going deeper into the Antikythera Mechanism - a box with 30 bronze gears inside connected to three dials outside. It predicted the movements of a bunch of astronomical data. But let's start with eclipses of the Sun.

We tend to think of computers as being a fairly recent invention. But the world’s oldest known computer is actually a few thousand years old. It’s called the Antikythera Mechanism

Gazing off into empty space or being the target of a ‘stare bear’, it can happen to us all. Staring into the middle distance can be relaxing and head-clearing, but fixing our eyes on nothing at all for a very long time can be just plain dangerous.

The last few episodes have considered the difference between a virus and a bacterium; wondered whether a virus is alive or not; and looked at our discovery of these incredibly tiny critters. While mysteries surrounding viruses are intriguing, without them we couldn’t have babies or even think.

This COVID-19 pandemic is the first one for 102 years. In 1918-1920 we had an influenza pandemic, which we now refer to as the Spanish Flu. Back then we didn’t know about a thing called a ‘virus’, so in 1918 no-one knew what was killing people. But we did know about germs.

Bacteria and viruses both have the genetic code needed to make babies but only a bacterium has all the biological machinery to make another bacterium. A virus has to get into a cell and make it start manufacturing copies of the virus. So, is a virus 'alive' – well, depends on the definition.