Explore every episode of the podcast Great Moments In Science

Dr Karl was first heard on the wireless in 1981 when he convinced Triple J that a talk about the space shuttle would be good listening because he had applied to be a NASA astronaut. The shuttle did (eventually) launch ... and along with it, the all-science-media career of one Dr Karl Kruszelnicki.

This is Dr Karl's last Great Moment in Science, as we know it—but don't worry, he'll still be around and firing on all cylinders—including on Triple J's Science with Dr Karl podcast.

Science with Dr Karl

We know that the drug called cannabis, or marijuana, increases the appetitecommonly called the 'Marijuana Munchies', and we are finally getting closer to knowing what makes it happen. Half-a-billion years ago a biological system evolved to make sure that hungry animals would eat.

What you eat or drink just after you finish pumping iron is crucial to laying down muscle. 

Dr Karl weighs up the best way to bulk up, in this archive episode of Great Moments in Science from 2011. 

What can chickens teach us about the way out of a pandemic?

Chlorophyll water has re-emerged as a darling of the wellness world - but does it stand up to the hype?

Chlorophyll water has re-emerged as a darling of the wellness world - but does it stand up to the hype?

It's not a good plan to skimp on sleep. A regular seven to nine hours a night puts you in a better position to live longer, and better.

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

The destructive force of a wall of snow is well known. Major avalanches can not only kill, they can also completely reshape a landscape.  

But it's not just mountainsides we need to worry about. There are also avalanches happening under the surface of the ocean — forging canyons and threatening our telecommunications.

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.

2020 will be remembered as the Year of the Virus – the first year of the COVID-19 pandemic. By early 2021 the COVID virus had truly left its mark on our population, lifestyle, and biosphere. But the universe is complicated, and viruses can be good guys too.

Trying to talk about the dollar value of a human life really sounds like cold hard economics. Knowing how the calculations are done is chilling. But human life does have a value. Bizarrely, trying to work that out began with trying to work out the "value of death".

Fake News has been around for thousands of years. You’ve probably heard of Nero, who was accused of playing the fiddle while Rome burned. But nowadays, the word gets around a lot faster. Thanks to the Internet and Social Media, a lie can travel around the world before the truth has even got out of bed. So fake news spreads quickly, and it takes more time to set straight than it took to tell the original lie.

More on how under-rated our sense of smell is – and how loss of smell can be an early indicator of COVID-19. In your DNA many of the genes associated with smell are located right next to a big bunch of genes that form your immune system. As a baseline, pre-COVID-19, about 1-5% of the general population had no sense of smell, and another 5-13% had a lessened sense of smell. But COVID-19 has bumped these percentages way up.

We see our human sense of smell as woefully inadequate compared to other animals – but awareness of our sense of smell has become more of a hot topic recently with the COVID-19 pandemic. A significant number of people who get the virus lose their sense of smell early on. It seems that a loss of smell can be a very good early sign of COVID-19 infection.

In a classic scientific 'urban myth' a physics student is asked to measure the height of a building using a barometer. In 2020 French and Italian physicists wrote a paper called 61 Ways To Measure The Height Of A Building With A Smart Phone. This opened up a bunch of extra-modern measuring methods because of the smartphone's array of internal sensory gadgets.

There are plenty of reasons why a person might poke their tongue out. 

Sometimes it can be a rude or cute gesture. Maori warriors do it as a sign of defiance, and Tibetans do it as a greeting.

But many times it's a sign of concentration. So here’s why your tongue helps your brain think.

Host: Dr Karl Kruszelnicki

Modern, pre-COVID, travel means it’s possible to trip around the world quite quickly. What if we had a super-advanced future rocket technology that could keep us accelerating at 1G. You could travel billions of light years - in less than a human lifetime!

During World War II a curious aircraft was built by the German air force. Its purpose was to combat Allied bombers, but not everything went to plan. What sounded like a ‘good idea at the time’ became, probably, the Worst Plane of World War II.

Why would the fossil fuel company BP promote the idea of reducing our individual 'carbon footprint'?

Climate change has begun displacing species, but just how many are on the move?

What was the mysterious Carrington Event of 1859? And why did it affect telegraph systems?

Is it true that our bodies would prefer the 'Paleo diet'?

What twisted trickery causes ribbons to curl?

What's the maximum number of hot dogs someone could eat in 10 minutes?

Where does the world's dust come from? And how does it constantly fill up our homes!?

Are discussions about your individual 'carbon footprint' really a distraction, shifting blame onto everyday citizens?

In development is an amazing new technology which may, eventually, turn your thoughts into speech. It's being designed to help people who can’t speak, turn what they're thinking into speech. But it’s still early days.

Would you eat a hamburger patty that was grown in a lab? What about fake meat that looks and tastes just like the real thing?

A cuppa tea can be a life-saver - sometimes, literally!

Understanding thyself, and taking the middle path, can lead to a much faster and calmer parking experience

Could we really rid the world of Hepatitis C?

Hepatitis C is one sneaky little disease, caused by an equally sneaky virus.

What is it with red food and stains? So many things!

Regrowing your tail is one thing - but what if you lose more than your tail in the first place?

Copper is like kryptonite to COVID-19.

They can be superemassive, but black holes still have no size.

Why you should always read back copies of the Journal of Fluid Mechanics.

Athletes are not just fit, they also attract a lot of media attention, especially if stories are put around that COVID vaccines are a cause of death in this group. In late 2021 such claims were being made - and they’re plainly not true.

That's not a dinosaur - it's a flying catapult!

Why are scientists exercising fish ... with a coffee plunger?

This creature has the only known case of an 'on-demand anus'