News
Successes in Science and Nature
The HiROS group have recently led one paper in Science, and featured prominently on other papers in Nature and Science.
- Kepler-36: A Pair of Planets with Neighboring Orbits and Dissimilar Densities.
- Fast core rotation in red-giant stars as revealed by gravity-dominated mixed modes.
- Ensemble Asteroseismology of Solar-Type Stars with the NASA Kepler Mission.
- Kepler Detected Gravity-Mode Period Spacings in a Red Giant Star.
- Gravity modes as a way to distinguish between hydrogen- and helium-burning red giant stars.
Birmingham Heroes Campaign
Professor Bill Chaplin has been featured as part of the University's Birmingham Heroes Campaign.
Musical stars help scientists search for new life
The BBC reports how Prof. Bill Chaplin and colleagues in the School of Physics and Astronomy are using asteroseismology – the study of the oscillations of stars – to study new exoplanetary systems discovered by the NASA Kepler Mission.
Kepler's surprise: The sounds of the stars
Data from NASA's Kepler space telescope have revolutionized the search for planets outside the Solar System — and are now doing the same for asteroseismology, with researchers from our group leading the way.
Podcast on asteroseismology
Ideas Lab is an innovative new project funded through the Higher Education Innovation Fund. Each Ideas Lab `Predictor Podcast' features a different academic expert scanning the horizon in their specialist field to give insider knowledge on new trends and key issues.
Bill Chaplin on Material World on BBC Radio 4
Bill Chaplin appears live on the BBC Radio 4 Programme Material World.
Sky and Telescope - Kepler's Bonus: New Insights on Stars
A report on the Kepler Mission from "Sky and Telescope" magazine.
You know how, in practically
every war movie, the captured soldier only gives his name, rank,
and serial number when being interrogated? For the longest time
astronomers have had the same problem probing the basic
characteristics of stars.
Temperature is the one easy quantity to measure; luminosity (total
energy output) is a snap if you know the star's distance. But other
essentials such as a star's diameter and mass are difficult to
measure directly unless it happens to be in a binary system or (pure
gold) an eclipsing binary system.
Well, get ready for what some scientists are already hailing as a
"golden age for stellar physics," thanks to observations being made
by NASA's Kepler spacecraft.
Kepler, you'll recall, was launched two years ago to make
wholesale discoveries of
transiting extrasolar systems and, it's hoped, to identify
worlds like Earth. It does so by staring at some 145,000 stars
near the Cygnus-Lyra border. Those results have steadily poured
in — just two months ago, mission scientists released a
list of nearly 1,200 exoplanet candidates,
many in multiple systems. Surely thousands more will be found.
That alone would be a boon to stellar studies, since those
transiting planets make it easy to determine their host stars'
masses and diameters. But now an international team of five dozen
scientists has found a way to extract those values for stars
without transiting planets. As the team writes in
April 8th's Science, continually monitoring the
light from all those stars has turned up many that periodically
pulse in brightness due to acoustic waves coursing through their
interiors.
"Asteroseismology" isn't new. Physicists have known for decades
that
the Sun rings like a bell at frequencies with periods ranging
from 1½ to 20 minutes. Each of these oscillation modes is
sampling different parts of the solar interior.
A couple of dozen other stars were known to oscillate too, but
Kepler's data has just blown the field of asteroseismology wide
open. "These new observations allow us to measure the detailed
properties of stars at an accuracy that wasn't possible before,"
notes Steve Kawaler, a coauthor of the paper from Iowa State
University.
Led by William Chaplin (University of Birmingham), the team
tracked more than 2,000 solar-type stars in Kepler's view for a
month, using a special spacecraft mode that measured their
brightness once per minute (versus the usual twice per hour). The
observers found that about 500 of these stars exhibit
oscillations, from which the stars' diameters and masses could be
determined. The details get a little messy, but the Kepler data
now provide a powerful new method for studying stellar interiors.
For example, Chaplin's team finds that Kepler's census of stellar
diameters is a good fit to predictions, but that the studied
stars generally have lower masses than expected. (The authors
note that the masses could be skewed by unresolved binary
systems.)
In any case, once these observations are melded with estimates of
the stars' ages (now in the works), the full import of these new
results will undoubtedly "shake up" astronomers' assumptions
about how stars form and the range of sizes and masses they're
born with.
Posted by Kelly Beatty, April 8, 2011
The original report can be found here.
Professor Elsworth awarded IoP Payne-Gaposchkin Prize
I am delighted to announce that
Professor Yvonne Elsworth has been awarded the Institute of
Physics 2011 Payne-Gaposchkin Medal and Prize. This is a
fantastic achievement (hot on the heels of Professor Martin
Freer's award last year) and the School send Yvonne our warmest
congratulations for this well-deserved award.
Further details and citation may be seen on the IoP
website.
Andy Schofield
Professor of Theoretical Physics
Head of School, Physics and Astronomy
Read the full article here.
BBC News - 'Music of the stars' now louder
The Kepler space telescope measures the sizes and ages of stars five times better than any other means - when it "listens" to the sounds they make.
Read the full BBC News article here.
Bill Chaplin in Washington
On Saturday 19 February 2010 the University's Professor Bill Chaplin, Reader in Solar and Stellar Physics was invited to Washington to deliver a speech at the American Association for the Advancement of Science (AAAS) 177th annual conference. The AAAS is an international non-profit organisation dedicated to the advancement of science globally. AAAS is also responsible for the publication of the internationally renowned and respected journal Science.
I was in Washington to speak at
the 177th annual meeting of the American Association for the
Advancement of Science, giving a talk as part of the session
'Kepler: Looking for Other Earths.' The Nasa Kepler
satellite is monitoring the brightness of around 150,000 stars,
looking for earth sized planets in the 'Goldilocks' (habitable)
zones of their host stars. The data is being used to detect
minuscule changes in the brightness of the stars, due to
oscillations from trapped sound waves. This 'music in the
stars' is where I come in. I'm working with more than one
hundred colleagues around the world to study the music of stars
like our own sun (a field called asteroseismology).
Held in downtown Washington at the impressive DC Convention
Centre, the session was opened by the Kepler science lead,
Bill Borucki, a prominent Space Scientist who discussed the one
thousand planetary candidates that Kepler has discovered in its
first few months of operation. Just under seventy candidates
are earth-sized and around fifty of the one thousand candidates
appear to lie in the Goldilocks zones of the host stars.
Matt Holman, Smithsonian Astrophysicist and Lecturer at Harvard
University and Sara Seager, Ellen Swallow Richard Professor
of Planetary Science and Professor of Physics at the
Massachusetts Institute of Technology, next informed us of
the stars that have multiple planets and rocky 'Kepler 10-b'
planet which circles so close to its star that surface
temperatures are hot enough to melt iron!
My presentation focused on how Kepler is literally
revolutionising our ability to study stars like the sun, thanks
to the wonderful asteroseismology data it is giving us.
Asteroseismology colleague Conny Aerts also gave us an
informative talk about the fantastic results coming out of Kepler
on other types of stars. Finally, Martin Still (who is
responsible for the Kepler 'Guest Observer' programme) told
professional astronomers in the audience how they can get
involved.
In the following press conference, we discussed our results with
representatives of the international media. The
room was packed (I'd guess more than 100 journalists),
after we gave a short summary of what was presented,
starting with Bill Borucki, we fielded questions for the next
forty five minutes or so. After the press conference it's was off
to do some follow-up interviews, including Pallab Ghosh, the BBC
Science Correspondent and Alok Jha, the Guardian's Science
Correspondent who interviewed me for his Science Weekly podcast.
Before the day ends I took the chance to chat to my fellow
presenters. After looking over some of the latest data and
discussing ideas for new analysis and projects, we chat over
recently worked on research papers that are about to appear.
The original report can be found here.