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May 2008 Extra

May 2008 Extra

This issue we talk to Dr Anthony Challinor from the University of Cambridge about the Cosmic Microwave Background. We also get your astronomical questions answered by Dr Tim O'Brien.


Looking in different directions on the sky with radio telescopes we can see how the temperature of the universe is very nearly the same in all directions, but not quite identical. The fluctuations in this cosmic microwave background radiation tell us how matter was clumped together when the universe was about one thousandth its current size. Anthony Challinor describes how we've measured these fluctuations and how they are related to fluctuations on tiny scales in the very early universe.

Ask an astronomer

Nick puts listener questions to Dr Tim O'Brien. Mark asks why, if the supermassive blackhole at the centre of our galaxy is so massive, do the planets orbit the Sun rather than that blackhole. Chris Revvy asks why galaxies can collide if the universe originated from one point in the big bang and is expanding. Finally, Malcolm Powell asks how people get into astronomy as amateurs or professionals.

Show Links

Interview with Dr Anthony Challinor (University of Cambridge)

Ask an astronomer - gravity, colliding galaxies and becoming an astronomer

Show Credits

Interview:Dr Anthony Challinor and Nick Rattenbury
Ask an Astronomer:Dr Tim O'Brien and Nick Rattenbury
Presenters:David Ault and Stuart Lowe
Editors:Stuart Lowe and Roy Smits
Segment Presenter:
Website:Stuart Lowe
Cover art:The Cosmic Microwave Background Radiation Credit: COBE/NASA

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