Science In Action

Scientists know very little about the first few days of the life of a human embryo, once it's been implanted in the womb. Yet this is when the majority of pregnancies fail. Professor Magdalena Zernika-Goetz at Cambridge University is a leader in the field of making 'model embryos' in both mice and humans. Model embryos until now have been grown in the lab from donated fertilised eggs, but these are hard to come by and governed by strict laws and ethical guidelines. Now researchers in the University of Michigan have used human pluripotent stem cell lines (originally isolated from embryos, but kept and nurtured as clumps of dividing cells in petri-dishes for many years) to make a model embryo that has shown signs of development and organisation in the crucial 7-10 day window. Magdalena and Roland Pease discuss how helpful these will be to understanding crucial early stage pregnancies and as a tool to test drugs, treatments and disease processes. The ethical side of growing human embryos from stem cells is addressed by Stanford University ethicist Professor Hank Greely.Astronomers have detected water vapour in the atmosphere of a planet called K2-18b orbiting within the habitable zone of a distant star. The lead scientist, Professor Giovanna Tinetti of University College London, talks to Roland about the discovery and what she hopes to explore when a satellite telescope called ARIEL is launched by ESA in around a decade. And an amateur astronomer has discovered a comet that appears to have arrived from outside our Solar System. This observation follows on from that of Oumuamua which looked like it was an asteroid that had escaped from an exoplanetary system. Roland asks professional astronomers Alan Fitzsimmons of Queens University Belfast and Simon Porter from South West Research Institute in Colorado what they make of the latest interstellar visitor. (Picture: A set of five embryo-like structures in a microfluidic device developed in the lab of Jianping Fu. The top row consists of “immunostaining” images in which key proteins are tagged with dyes to label different cell types, whereas the bottom row shows standard photos taken through a microscope. Parts of the bottom images were blurred to more clearly show a correlation between the rows. Image credit: Fu Lab, Michigan Engineering)Presenter: Roland Pease Producer: Deborah Cohen

An isotopic fingerprint is reported of a nuclear explosion in Russia last month. Researchers ask people living in the area or nearby to send them samples of dust or soil before the radioactive clues therein decay beyond recognition. Also, a near miss between an ESA satellite and a SpaceX/Starlink module in crowded near space strengthens the case for some sort of international Space Traffic Management treaty, whilst in the arctic circle, melting permafrost is disinterring the graves of long-dead whalers.(Photo:Tell-tale radioactive isotopes could still be in dust on cars near the site of the blast. Credit: Humonia/iStock / Getty Images Plus)Presenter: Roland Pease Producer: Alex Mansfield

A computer processor made of carbon nanotubes is unveiled to the world. Also, the continuing quest for nuclear fusion energy, and the stats on crocodile attacks since the 1960s.(The world's first 16 bit microprocessor made of carbon nanotubes. Credit: Max Shulaker)

As fires across the amazon basin continue to burn, we speak to the researchers watching from space and from the ground. Also, new pictures back from the surface of asteroid Ryugu thanks to Germany’s MASCOT lander, part of the Japanese Hyabusa2 mission, give insights into the clay from which the solar system was originally formed, and Greenland’s top geologist gives his valuation of his native island for prospective purchasers.Presenter: Roland Pease Producer: Alex Mansfield(Photo: Wildfires in Amazon rainforest. Credit:REUTERS/Ueslei Marcelino)

Scientists this week are on expedition around the volcano Anak Krakatoa, which erupted and collapsed in 2018 leading to the loss of some 400 lives on the island of Java. The scientists, including David Tappin and Michael Cassidy, are hoping that their survey of the seafloor and tsunami debris will allow them to piece together the sequence of events, and maybe find signs to look out for in the future. Wyoming Dinosaur trove The BBC got a secret visit to a newly discovered fossil site somewhere in the US which scientists reckon could keep them busy for many years. Jon Amos got to have a tour and even found out a tasty technique to tell a fossil from a rock.Bioflourescent Aliens Researchers at Cornell University’s Carla Sagan Institute report their work thinking about detecting alien life on distant planets orbiting other stars. Around 75% of stars are of a type that emits far more dangerous UV than our own sun. What, they argue, would a type of life that could survive that look like to us? Well, just maybe it would act like some of our own terrestrial corals, who can protect their symbiotic algae from UV, and in doing so, emit visible light. Could such an emission be detectable, in sync with dangerous emergent UV flares around distant suns? The next generation of large telescopes maybe could…Exopants Jinsoo Kim and David Perry of Harvard University tell reporter Giulia Barbareschi about their new design for a soft exosuit that helps users to walk and, crucially also to run. They suggest the metabolic savings the suit could offer have numerous future applications for work and play.(Photo: Volcano Anak Krakatoa. Credit: Drone Pilot, Muhammad Edo Marshal, ITB university in Bandung, Indonesia)Presenter: Roland Pease Producer: Alex Mansfield Reporter: Giulia Barbareschi

The US has withdrawn from a historic nuclear disarmament treaty. However the verification of such treaties has been under scrutiny for some time as they don’t actually reveal the size of nuclear stockpiles. New methods of verification and encryption should allow all sides to be more confident on who has what in terms of nuclear stockpiles.Can carbon capture and storage technology help reduce atmospheric Co2 levels? The answer seems to be yes, but at a considerable cost.And we go for a cold swim around some hydrothermal vents.Photo: U.S. President Donald Trump and Russian President Vladimir Putin. Credit: Sputnik/ReutersPresenter: Roland Pease Producer: Julian Siddle

Wildfires are an annual phenomenon across the arctic region, but this year they are far more intense than usual, we look at the drivers for these extreme fires and the consequences, in particular long term environmental change across the region. We visit Naples which is built on a super volcano. A new analysis is designed to help predict when it might erupt. We hear from young scientists around the world on their hopes for the future and hear about the discovery of a new potentially earth like planet.Presenter: Roland Pease Producer: Julian Siddle(Photo: Arctic wildfires: Credit: Getty Images)

A global project tracking sharks through the deep oceans has found they are increasingly facing danger from fishing fleets. Sharks used to be caught accidentally, but now there is a well-established trade in shark meat and fins, which the researchers say is reducing their numbers. We look at how tourists might be a useful source for conservation data, And we meet one of the planets smallest predators, is it a plant is it an animal? Well actually it’s a bit of both.(Photo: Tiger shark. Credit: Barcroft Media via Getty Images)Presenter: Roland Pease Producer: Julian siddle

It’s 50 years since the moon landing and 25 years since Shoemaker - Levy 9 crashed into Jupiter. The Apollo missions returned to earth with cargos of moon rocks and the comet crash showed us what happens when celestial bodies collide. We look at the significance of both this week, and also contemplate a return to the moon. What will the next generation of moonwalking astronauts do there? One thing’s for sure, they’ll be examining moon rocks once more – though this time with a range of scientific tools which hadn’t been invented when the Apollo missions ceased. Picture: Shoemaker – Levy 9 Comet Impact Marks on Jupiter Credit: Getty ImagesPresenter: Roland Pease Producer: Julian Siddle

Researchers in Saudi Arabia have developed a prototype solar panel which generates electricity and purifies water at the same time. The device uses waste heat from the electricity generating process to distil water. An individual panel for home use could produce around 4 litres and hour. The researchers suggest use of such panels would help alleviate water shortages.A long running study of gorilla behaviour in the DRC has found they exhibit social traits previously thought to only be present in humans. This suggests such traits could have developed in the prehistory of both species. More than 500 fish species can change sex. Analysis of the underlying mechanism shows how sex determination is heavily influenced by environmental and in the case of one species social factors.(Picture: Future PV farm: not just generating electricity, but also producing fresh water. Credit: Wenbin Wang) Presenter: Roland Pease Producer: Julian Siddle