Arctic Terns, Satellites and Conker Trees

A podcast from the Planet Earth Online collection and the Natural Environment Research Council (NERC). As the map of Earth's gravity – as revealed by the European Space Agency's (ESA) sleek GOCE satellite – comes into sharper focus, Richard Hollingham speaks to a researcher who tells us what early results from the satellite show.

Another report finds out how ESA's ice mission, CryoSat-2, is getting on. The satellite was launched in April and will make precise measurements of both the shape and thickness of ice in the Arctic and Antarctica. It is now going through the all-important calibration stage. There is also a look at the science of conker trees.

And finally, a report finds out how scientists know exactly how far the incredibly fit Arctic tern flies every year. The bird holds the record for the longest migratory species in the world. Not bad for a creature that weighs no more than a blackbird. This podcast is dated 2 August 2010. NERC is a part of the Research Councils UK (RCUK) partnership of research councils.