March 2012 Extra: The Light Side

In the show this time, Prof. Philippa Browning tells us about the upcoming National Astronomy Meeting and solar physics in the JodBite, we talk to Prof. Tom Shanks about cosmological theories that avoid the need for dark matter and dark energy and Dr Cristiano Sabiu discusses how to study the large-scale Universe using observation and theory. Your astronomical questions are answered by Dr Tim O'Brien and we round up some odds and ends from the sphere of astronomy.

JodBite with Prof. Philippa Browning

We talk to Prof. Philippa Browning about her involvement with the upcoming National Astronomy Meeting (NAM) and the several public events that will revolve around it. She then goes on to discuss our closest star, the Sun, where she explains our current understanding of how the surface of the Sun is cooler than the corona and the unpredictability of solar flares.

Interview with Prof. Tom Shanks

Prof. Tom Shanks is a cosmologist at the University of Durham. In this interview, Tom talks about the Standard Cosmological Model and the evidence for cold dark matter and dark energy. He also discusses simpler alternative models and their main challenges.

Interview with Dr Cristiano Sabiu

Dr Cristiano Sabiu of University College London talks about his work on cosmology and the large-scale structure of the Universe. He tells us how it is possible to map the underlying matter distribution of the Universe by measuring the effects that weak gravitational lensing has on the apparent shapes of distant galaxies, and how this information can be used to test the predictions of our current cosmological models that are made using N-body simulations.

Ask an Astronomer

Dr Tim O'Brien answers your astronomical questions:

• The first question this month is from Peter. He wrote in to say: "I was thinking, as you do, what happens when two black holes merge. Since time slows exponentially as you near the singularity, will a second black hole's singularity ever meet the original one, and for that matter does anything drawn into a black hole ever reach the singularity?"
• The next question is from David, who asks: "If other civilisations across the Universe had the ability to do a cosmic microwave background (CMB) survey of the sky and it was any time in the current - let's say - one-billion year window, would they see the same pattern of blotches that we see in our CMB pictures? Is the CMB the same background for all points in the Universe?"
• Finally, Andrew who has written in to say: "In their book, 'Why Does E=mc²?', your University of Manchester colleagues Brian Cox and Jeff Forshaw wrote that a double pulsar produces gravitational waves that take energy away from their orbital motion and cause them to spiral inwards. They also wrote that astronomers at Jodrell Bank and elsewhere were able to measure the rate at which the one known double pulsar spirals inwards to be 7mm per day, which agreed with the prediction of general relativity. Can you explain a bit more about gravitational waves and how this measurement was done?"
  You can listen to a Jodcast interview with Prof. Michael Kramer about the double pulsar.

Odds and Ends

In the age of space tourism, the London Science Museum has attempted to improve space food by serving up a special in-flight menu devised by food artists The Robin Collective, space nutrition specialist Professor Brian Ratcliffe and Britain's first astronaut, Helen Sharman. They came up with such dishes as Pot Roast Apollo, a pot-noodle-style dehydrated roast dinner.

NASA will launch five rockets in five minutes within the next couple of weeks. They won't go into space, but will give out vapour trails around 60 miles above the Earth's surface to allow scientists to study the behaviour of turbulent air in a relatively poorly understood layer of our atmosphere called the thermosphere where winds of over 300kph can move around the planet in a matter of days.

On Saturday the 3rd of March, anyone looking up at the British night sky at around 9:40pm would have witnessed an extremely bright meteor breaking up in the Earth's atmosphere. Other such rare events in the past have led to strange and unusual phenomena, from ghostly sounds and sights during meteor showers to inspired scientists getting a little bit poetic.

Jodcast listener Susan Tang has produced an astronomy podcast for children, Astronomy For Kids, which has now released two of its monthly episodes.

Show Credits