BBC Inside Science Folgen

About 66 million years ago an asteroid at least 6 miles wide crashed into the Earth, in the shallow sea that is now the Yucatan Peninsular in Mexico. It gouged the Chicxulub crater 18 miles deep; threw 25 trillion tonnes of debris into the atmosphere, much of which was hotter than the Sun, created huge seismic waves and massive tsunamis churning the Gulf of Mexico, tearing up coastlines and peeling up 100’s of metres of rock. 75% of the Earth’s forest burned. Debris was thrown out across the Solar System and North America was showered by a fan of glassy molten rock droplets. This geological event marked the end of the Cretaceous period and the start of the Palaeogene. Most people accept that this massive event caused the last great extinction, the end of the dinosaurs and a period of intense cold. Many fossil finds back this theory up. But very little fossil evidence showing the impact of the actual event has been found. Until now. Hundreds of miles from Chicxulub in a fossil site called Tanis, in North Dakota, part of the vast Hell Creek formation, is a fossil find that depicts the turmoil 10's of minutes after the asteroid hit. Marine and freshwater fish are found tangled together with these glassy droplets crammed in their gills, Charred trees are mixed up with hundreds of mangled animal bones, amber perfectly preserving drops of what was molten Earth. It's got palaeontologists including Professor Phil Manning at Manchester University very excited.The gravitational wave detectors LIGO and VIRGO have been recently upgraded and made more sensitive to the miniscule signals that denote ripples in gravity - gravitational waves. Professor Sheila Rowan of the University of Glasgow explains to Gareth Mitchell that she hopes that with this third run of the detectors, they will be finding not just one or two signals that provide evidence of massive events in our universe, but hundreds, maybe even thousands.In the quest to understand how corals are affected by rising sea temperatures we need to understand the symbiotic relationship they have with dinoflagellates, the single-celled algae that live in, and use photosynthesis to make food for the coral. When coral gets too hot and undergoes 'bleaching', this is the algae leaving the coral. Yixian Zheng at the Carnegie Institution of Washington takes Roland Pease on a tour of her coral tanks and explains that she's hunting for a model coral organism to study this process at the genetic and molecular level.A crime has been committed in the studio. Gareth's tea has been drunk and his biscuits have been nibbled. Luckily evidence was left at the scene of the crime - a shoeprint with distinctive wear patterns. One quick phone call and the director of the Leverhulme Research Centre for Forensic Science at the University of Dundee, Professor Niamh Nic Daeid is on the case. She's asking the public to help build up a database of footwear prints. The project is the largest ever study into the variation in footwear marks made by the same shoes across different surfaces and activities so that the variation observed can be used to explore links between the shoe and the mark it makes. In order to do this, she's asking thousands of individuals to take part in a large-scale citizen science project by taking pictures of their footwear and the marks they make. This will help the Dundee team build a substantial database for use in their research to aid the scientific validation of footwear marks as evidence for use in the criminal justice system.Producer (and biscuit thief) - Fiona Roberts

One of the longest running insect pollinator surveys in the world, shows that a few generalist pollinators are on the increase, whereas specialist insects are declining. Using data collected by volunteers across Great Britain to map the spatial loss of pollinator insect species, the study by the CEH (Centre for Ecology and Hydrology) measured 353 wild bee and hoverfly species across the country. The results showed that on average, each 1km2 survey patch lost an average of 11 species from 1980-2013. CEH's Professor Helen Roy and Dr Claire Carvell explain to Marnie Chesterton how volunteers can take part in the next survey.Want to know where a whale has been? Just ask the barnacles on its head! Barnacles hitchhike on whales, and they’ve been doing this for millions of years. When barnacles grow they add to their carbonate shells using compounds from their surroundings. As the whales migrate, the barnacles take up compounds from the different oceanic locations. A bit like filling in a travel diary, or collecting passport stamps. If you can decipher the chemical code laid down in the barnacle shells, you can work out where the whale has been on its oceanic migrations. This is what researcher Larry Taylor, at University of California Berkeley, has been doing and he says that the information can even be found in fossilised whales (and barnacles.)The patterns signals in our brain make when we are falling asleep are quite hard to study. But thanks to a few people who manage to fall asleep in an FMRi scanner, we now know there are multiple stages of sleep. Professor Morton Kringlebach, a professor of neuroscience at the University of Oxford likens the pattern of brain activity, as it enters the various sleep stages, to the choreography of a dance. His friend, Dr. Milton Mermikides at the University of Surrey, goes one further. As a composer and academic expert in jazz, he thought the pattern of brain activity was like chord changes in jazz music. So he put the sleepy brain to music. Marnie listens to the soporific tones and asks if people with disordered sleep, such as insomnia or restless leg syndrome would make different music?Producer: Fiona Roberts

30 years ago Tim Berners-Lee invented the World Wide Web as a way to let physicists share their papers and data on a distributed network. It's changed a lot since then and not all for the better. Dominant technology companies monopolise our data and many, including Berners-Lee are worried about the growth of state sponsored hacking, misinformation and scamming. One solution is to re-decentralise the web, giving us more control of our information and what is done with it, but at what cost? Founder and director of Redecentralize.org, Irina Bolychevsky and technology guru Bill Thompson discuss the future.BBC Space Correspondent Jonathan Amos has news on some space rocks this week. Ultima and Thule, make up a bi-lobe comet out in the far reaches of the Solar System in the Kuiper Belt. Ultima-Thule was visited by the New Horizons mission in January. More data is being analysed and giving scientists insight into how these two planetary building blocks collided and merged and also on how it got its strange flattened shape. Another rock seems to be a rubble pile. The asteroid Ryugu is currently hosting the Japanese Space Agency's Hayabusa 2 spacecraft and landers. Jonathan explains to Gareth what stage the missions' audacious sample collect and return is now at. And there's a shock discovery by spacecraft OSIRIS-REx from asteroid Bennu. The NASA spacecraft analysing the asteroid has observed it shooting out plumes of dust that surround it in a dusty haze. It's a phenomenon never seen in an asteroid before.Back down on Earth and under the surface of the earth are the earthworms. As any savvy gardener will know, earthworms make a big difference to the health of soil and plants. What isn’t as well understood is how changes to the soil - like climate change and the intensification of agricultural practices - have impacted on the all-important worm population. In fact, scientists don’t even know what’s down there, wriggling underneath the surface. To find out, farmers recently undertook to the first worm survey in the UK. Finding that 42% of fields had very few or completely lacked key types of earthworm, the results suggest that over-cultivation has led to poor soil health in significant amounts of farmland. Producer: Fiona Roberts