Date of issue: tbc
SCOTS SCIENTIST TO ‘REFINE’ SIZE OF UNIVERSE
Answer to problem is in the stars.
astronomer at the University of St Andrews will use a powerful
planet-hunting telescope to find out the true size of the Universe.
Researcher Dr Alan Penny will use the brightness of half a dozen stars to refine estimates of how big the Universe actually is. Dr Penny hopes to solve the problem using the ‘extreme precision’ of NASA’s Kepler satellite launched into space last month.
for the search for new planets, Kepler's main task is to look for
planets by monitoring the brightness of 100,000 stars. But Dr Penny,
a member of a 200 strong international team, will use the same data
to study a much smaller sample of stars.
He explained, "While Kepler is doing its exciting planet-hunting, we will be using its extreme precision to resolve a possible problem with our measurement of the size of the Universe.
"These variable stars known as 'Cepheid' form the base of a series of steps by which we measure the distance to distant galaxies and, through them, we can measure the size of the Universe".
it is highly likely that scientists’ understanding of how these
stars vary in brightness is incomplete, Dr Penny will use the six
stars as a basic yardstick to work out how much previous estimates of
the size of the Universe are wrong.
He explained, “These Cepheids stars which get brighter and fainter by some tens of percent every ten to a hundred days are mostly understood. But recently it has become clear that our theories of what happens in the outer layers of these stars which cause the variations in brightness do not totally agree with what we see.
exquisite accuracy of Kepler in measuring star brightness, one
hundred times better than we can do from the ground, means we can get
such good measurements that we should be able to match theory with
observation. Resolving the issue may only change estimates of the
size of the Universe by a small amount, but we won’t rest easy
until the problem is solved," concluded Dr Penny.
NOTE TO EDITORS:
Dr Alan Penny is available for interview on email email@example.com or tel 07804 670 620.
More information on the Kepler mission is available at http://www.nasa.gov/kepler
NOTE TO PICTURE EDITORS:
of the Kepler space telescope are available via:
Contact Gayle Cook, Senior Press Officer on 01334 467227 / 462529, mobile 07900 050 103, or email firstname.lastname@example.org
View the latest University press releases at www.st-andrews.ac.uk