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THE MATERIAL WORLD
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Quentin Cooper reports on developments across the sciences. Each week scientists describe their work, conveying the excitement they feel for their research projects.
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Contact Material World |
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LISTEN AGAIN 听30 min |
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PRESENTER |
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"For me science isn't a subject, it's a perspective. There are fascinating scientific aspects to everything from ancient history to the latest gadgets, outer space to interior decorating; and each week on The Material World we try to reflect the excitement, ideas, uncertainties, collisions and collaborations as science continues its never-ending voyage into the unknown".
Quentin Cooper |
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An artists' impression of the impactor spacecraft听smashing into an asteroid while observed by the orbiter spacecraft听
(credit: ESA - AOES Medialab) |
Deflecting Asteroids
听
Trying to nudge astronomical objects into new orbits might sound as futile as jousting with windmills, but it's the goal of a new European Space Agency mission now being planned.
It's appropriately named Don Quijote, and it could lead to a way of saving humanity from global catastrophe.
There are probably more than a thousand NEOs - Near Earth Objects - that cross the Earth's orbit and that could one day hit our planet.听
It's estimated that one about a kilometre across might collide with us every 300,000 years, unleashing the energy equivalent to all the world's nuclear arsenal detonating at once. But with enough notice, just a slight nudge could make such an asteroid miss us by a safe margin.
Three different consortia are drawing up plans for a mission to test the technology for diverting NEOs; ESA will then select the best. In each of them, one spacecraft, called Sancho, will go into orbit around an asteroid, survey it with great accuracy and then look on from a safe distance while the second, Hidalgo, lunges at the asteroid at a speed of 10 km per second.
Quentin Cooper is joined by Quijote scientist Dr Sima Adhya of QinetiQ, and by Professor Alan Fitzsimmons from Queens University Belfast who is a member of ESA's NEO Advisory Panel.
The Regeneration Game
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Scientists at the University of Manchester have developed a new technique which uses electricity to engineer human tissue.
It uses electric fields to build up layers of cells to form tissue and is being used to create hematons - aggregates of blood producing cells essential in the function of healthy bone marrow.
Chemical engineer Gerard Markx has developed the technique based on a phenomenon called dielectrophoresis. The cells are attracted to the regions between two electrodes where they build up in layers and tissues are formed.
The use of electricity gives greater control over cells than is currently possible, because by varying the voltage and using different shapes, cells can be positioned and stacked on top of each other in any pattern.
Different electric fields attract different types of cells. Most important of all is the fact that the cells can be kept alive and active.
Gerard Markx and his research team have so far created tissue 200 microns thick.
This is听one step on the road to creating artificial bone marrow outside the body and produces any given blood type.
Although this is a long way off, it means the treatment of bone marrow diseases like leukaemia could become easier and more effective. |
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