Question of the Week, from the Naked Scientists

This week, Matt contacted us asking "With three space missions currently converging on Mars how do the nations avoid orbital collisions? Do they share data, do they have transponders or space traffic control etc?". Katie King spoke with Chris Bridges, academic at Surrey Space Centre in the University of Surrey to find out how we keep our spacecraft from colliding.... Like this podcast? Please help us by supporting the Naked Scientists

This week, listener Rob emailed us to ask "Is dark matter in large lumps or like grains of sand?" Iacopo Russo got some help from the Little Prince story, as well as from Physics professor Francesca Day at Durham University and physicist Jacques Pienaar from the University of Chicago, to find the answer... Like this podcast? Please help us by supporting the Naked Scientists

To answer this juicy question, Julia Ravey asked environmental scientist at the University of York Samarthia Thankappan... Like this podcast? Please help us by supporting the Naked Scientists

Teacher Ellie was recently asked a question by her Year 9 pupil in Manchester that she couldn't answer: "I have one blue eye and one brown eye, when I have kids, will they have one blue eye and one brown eye like me?" Eva Higginbotham put the question to eye colour expert David Mackey from The University of Western Australia... Like this podcast? Please help us by supporting the Naked Scientists

Daniel has been dreaming of the stars, but his dreams have been rather eerie. Now, he's on a one way journey to gain some scientific insight. He got in touch to ask 'If a crew on a mission to mars had a death on board, and if that body was released into space, would it ever decay?' Matthew Bothwell, public astronomer at the University of Cambridge, spills the beans on what would happen to human remains if they were ejected out into infinity and beyond... Like this podcast? Please help us by supporting the Naked Scientists

This week, listener Rick emailed us to ask "Why do we acquire lifelong immunity against some pathogens but not others?" Sally Le Page asked author and infectious disease researcher at Imperial College, London, John Tregoning, to jog our memories... Like this podcast? Please help us by supporting the Naked Scientists

Margaret got in touch to ask The Naked Scientists: "Science has now identified actual nerve endings that humans and other mammals have that send that itchy feeling to the brain. Do snakes and other amphibians have these same nerve types? Have frogs been seen scratching an itch?"Harry Lewis dived deep to find an answer and Gerhard Schlosser from the National University of Ireland Galway was on hand to tell him more... Like this podcast? Please help us by supporting the Naked Scientists

Listener Mark was curious to know: "Since the Universe is expanding, and light coming across it stretches as it does so, becoming more red, what happens to the lost energy when the shorter wavelength, higher energy light towards the blue end of the spectrum is shifted into lower energy, red wavelengths?" Cameron Voisey went off to figure it out... Like this podcast? Please help us by supporting the Naked Scientists

Listener Martin wanted to know: "How long does it take the food I eat to become part of me?" Eva Higginbotham set off to find out the answer... Like this podcast? Please help us by supporting the Naked Scientists

Dave got in touch with The Naked Scientists to ask, "How much of the brain is memory?" This week Harrison Lewis only just remembered to get in touch with Amy Milton from the University of Cambridge. Thank goodness he did, as Amy has extensive experience wrapping her head around this brain teaser... Like this podcast? Please help us by supporting the Naked Scientists