Sounding the Stars - Asteroseismology of Stars with Sun-like Oscillations
Lead Research Organisation:
University of Birmingham
Department Name: School of Physics and Astronomy
Abstract
Stars are building blocks of the universe, and are crucial sources of energy for giving conditions which can support life. Knowledge on how stars are born, live, evolve, and then die, underpins much of our understanding of the universe. Our research will 'peer' deep inside stars to understand how they work, and to add previously unknown knowledge on the life-cycles of the stars. Our research will also provide important information for 'planet hunters', who are searching for potentially habitable planets like Earth orbiting other stars. We are interested in stars that vibrate gently like our own star, the Sun. Although you cannot see it without special equipment, the Sun is shaking. Bubbling motion just under the visible surface of the Sun is constantly feeding in energy, and the Sun responds by vibrating just like a (very) large musical instrument. The 'notes' of the Sun's music are very interesting to astronomers. They are made by sound waves, some of which have travelled deep inside the Sun, and their frequencies (the pitch of the notes) depend on conditions they meet on the way. For example, the frequencies depend on the density and temperature of the material inside the Sun, and studying them allows astronomers to essentially get an ultrasound scan of our nearest star by 'sounding' its interior. Because the Sun is a ball of largely ionized gas, when it shakes it gently oscillates. The oscillations make the surface move to and fro at a couple of metres per second (a slow walking pace!), and it takes about 5 minutes to go through a complete cycle. Just detecting this small movement is very hard, and takes specially designed instruments. But doing so for other stars is much, much harder again, because they are many orders of magnitude fainter than the Sun. The solar oscillations were discovered in the 1960s, and it took until the mid to late 1990s for ingenious astronomers to discover oscillations like them on another star. There are now more than a dozen stars that have been observed to oscillate like the Sun. They range from stars that both look like, and are at the same points in their life cycles, as the Sun; through to much more mature stars that have expanded in their old ages to become 'red giants'. We now stand on the threshold of an exciting expansion in observations of the oscillations on other stars, with the launch of new space missions, and continuation of observations from telescopes around the world. These observations will allow astronomers to test their theories of how all stars live and evolve, by peering into their interiors, like we can for the Sun. That is what we propose to do. We will use the exciting new data from telescopes and space missions to 'sound the stars'. Our work will also go hand-in-hand with searches for Earth-like planets around other stars. That is because we will use data from NASA's Kepler space mission, which will look for oscillations and hunt for planets, at the same time. Our work will help to reveal the nature of stars around which planets are found, and will also give us more information on the planets themselves.
Publications
Ballot J
(2011)
Accurate p-mode measurements of the G0V metal-rich CoRoT target HD 52265
in Astronomy & Astrophysics
Hekker S
(2011)
Frequency dependence of the large frequency separation of solar-like oscillators: influence of the helium second-ionization zone Frequency dependence ??: influence of He ii
in Monthly Notices of the Royal Astronomical Society: Letters
Goss K
(2011)
Variations of the amplitudes of oscillation of the Be star Achernar Variations in the oscillations of Achernar
in Monthly Notices of the Royal Astronomical Society
White T
(2011)
ASTEROSEISMIC DIAGRAMS FROM A SURVEY OF SOLAR-LIKE OSCILLATIONS WITH KEPLER
in The Astrophysical Journal
García R
(2011)
Preparation of Kepler light curves for asteroseismic analyses Preparing Kepler asteroseismic light curves
in Monthly Notices of the Royal Astronomical Society: Letters
Verner G
(2011)
Global asteroseismic properties of solar-like oscillations observed by Kepler: a comparison of complementary analysis methods Global asteroseismic properties from Kepler
in Monthly Notices of the Royal Astronomical Society
Hekker S
(2011)
Characterization of red giant stars in the public Kepler data Characterization of red giant stars
in Monthly Notices of the Royal Astronomical Society
Mathur S
(2011)
SOLAR-LIKE OSCILLATIONS IN KIC 11395018 AND KIC 11234888 FROM 8 MONTHS OF KEPLER DATA
in The Astrophysical Journal
Chaplin W
(2011)
EVIDENCE FOR THE IMPACT OF STELLAR ACTIVITY ON THE DETECTABILITY OF SOLAR-LIKE OSCILLATIONS OBSERVED BY KEPLER
in The Astrophysical Journal
Campante T
(2011)
Asteroseismology from multi-month Kepler photometry: the evolved Sun-like stars KIC 10273246 and KIC 10920273
in Astronomy & Astrophysics
Description | Our research from this grant (now completed) used asteroseismology to further our understanding of the structure and evolution of other Sun-like stars in our Galaxy, including stars hosting planets. |
Exploitation Route | Our outputs have added important knowledge to the international astronomy community, and have been utilized by us and others in research that builds on these findings. |
Sectors | Other |
Description | Our outputs have added important knowledge to the international astronomy community, and have been utilized by us and others in research that builds on these findings. |
First Year Of Impact | 2008 |
Sector | Other |
Description | ISSI Workshop Programme |
Amount | £30,000 (GBP) |
Organisation | International Space Science Institute (ISSI) |
Sector | Academic/University |
Country | Switzerland |
Start | 03/2010 |
End | 12/2011 |
Description | CoRoT |
Organisation | National Centre for Space Studies (CNES) |
Country | France |
Sector | Public |
PI Contribution | Participation in data analysis of CoRoT stars |
Collaborator Contribution | CoRoT Data Analysuis Team leads work on analysis of asteroseismic data on solar-type stars observed by French-led CoRoT spacecraft; collaboration comprises ~20 academic institutes |
Impact | Papers in academic journals |
Start Year | 2009 |
Description | KASC |
Organisation | Kepler Asteroseismic Science Consortium |
Country | Denmark |
Sector | Academic/University |
PI Contribution | I lead the solar-type part of the collaboration; my team at UoB contribute significantly to KASC-related analysis |
Collaborator Contribution | Large international collaboration, coordinating research on asteroseismology with NASA Kepler Mission. I lead the largest part of the consortium, on solar-type stars. The benefits of this large collaboration are multifold, i.e., research papers, development of new analysis techniques, coordinated training of young members of the community etc. My part of collaboration has 170 members from academic institiutes around the world (too many to list here!) |
Impact | Many papers in academic journals (see publications list) |
Start Year | 2009 |
Description | SONG |
Organisation | Aarhus University |
Department | Department of Physics and Astronomy |
Country | Denmark |
Sector | Academic/University |
PI Contribution | - Contribution to preparation for analysis of data - Hardware contribution, provision of temperature controllers for part of set-up |
Collaborator Contribution | Collaboration on planned network called Stellar Observations Network Group (SONG): |
Impact | Some hardware contribution (see above) |
Start Year | 2009 |
Description | BBC Radio |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Numerous interviews for national and international radio, notably BBC. Also participation in BBC Radio programmes, such as guest on BBC Radio 4 "Material World" programme Excellent publicity for our research |
Year(s) Of Engagement Activity | 2009,2011,2012,2013 |
Description | BBC TV |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | BBC Breakfast TV; BBC News Channel; BBC television news Excellent publicity for our research |
Year(s) Of Engagement Activity | 2011,2012 |
Description | International Postgraduate Lecture Schools |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | Yes |
Type Of Presentation | Keynote/Invited Speaker |
Geographic Reach | International |
Primary Audience | Postgraduate students |
Results and Impact | Invited lecturer at international postgraduate schools Invitation to come back to participate in future schools; positive feedback from delegates |
Year(s) Of Engagement Activity | 2010,2012 |
Description | Newspaper interviews |
Form Of Engagement Activity | A press release, press conference or response to a media enquiry/interview |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Public/other audiences |
Results and Impact | Articles covering our research on asteroseismology in the UK and international press Excellent publicity for our research |
Year(s) Of Engagement Activity | 2010,2011,2012,2013 |
Description | Postgraduate Lecture Schools |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | Yes |
Type Of Presentation | Keynote/Invited Speaker |
Geographic Reach | National |
Primary Audience | Postgraduate students |
Results and Impact | Invited lectures for postgraduates in solar astronomy area Repeated invites; positive feedback from delegates |
Year(s) Of Engagement Activity | 2009,2010,2011,2012,2013 |
Description | Royal Society Summer Exihibition 2010 |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | Yes |
Type Of Presentation | Keynote/Invited Speaker |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | Several members of the group were on hand during the week to engage directly with the public, visiting the exhibition, which was held at the South Bank centre in London. Media activity; raising awareness with public; positive feedback from public |
Year(s) Of Engagement Activity | 2010 |
Description | Talks to Schools |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Type Of Presentation | Keynote/Invited Speaker |
Geographic Reach | National |
Primary Audience | Schools |
Results and Impact | Regular talks at schools locally and nationally Positive feedback, requests for further invitations |
Year(s) Of Engagement Activity | 2009,2010,2011,2012,2013 |
Description | Talks to astronomical societies |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Type Of Presentation | Keynote/Invited Speaker |
Geographic Reach | National |
Primary Audience | Public/other audiences |
Results and Impact | Regular talks to astronomical societies around the UK Positive feedback, plus invitations for repeat visits |
Year(s) Of Engagement Activity | 2009,2010,2011,2012,2013 |