Astronomy and Particle Physics

Written evidence submitted by Professor Gerry Gilmore,
UK Principal Investigator, Gaia mission (APP 18)

1 I respond re your enquiry regarding the impact of withdrawal from international ground-based facilities (e.g. Gemini Observatory, Isaac Newton Group of telescopes) on the UK’s research base, and opportunities for public outreach and inspiration of young scientists.

2 I comment as UK Principal Investigator for the European Space Agency Gaia mission. Gaia is ESA’s premier astrophysics mission of the next decade, due for launch in mid-2013. Gaia is a revolutionary satellite, which will provide the first ever 4-dimensional study of the Milky Way Galaxy, determining both where stars are in space, and –uniquely – how they are moving. Gaia science will quantify how the Milky Way Galaxy formed and assembled, create the first detailed map of how Dark Matter is distributed, quantify stellar evolution, determine the orbits of all near-Earth Objects, discovering all those in potentially dangerous earth-crossing orbits, make contributions to cosmology and fundamental physics, and very much more. It will be a revolution.

3 Gaia’s data processing requirements in the UK are funded by the UK Space Agency. Much of Gaia was built by UK industry.

4 A crucial aspect of space astrophysics, especially as related to quantitative studies of the whole Milky Way, is that the whole sky, north and south (as seen by us) is studied. Unique aspects are available only in the south – e.g. the centre of the Milky Way, or only in the north – e.g. the tidal debris of the Sagittarius galaxy, with which the Milky Way is currently merging, and whose orbit defines the distribution of Dark Matter in the Galactic halo.

5 Astrophysical studies of Dark Matter are the essential complement to interpretation of the (anticipated) results from the LHC at CERN. Cosmological results from Gaia, especially precision calibration of the cosmological distance scale, are not only of high intrinsic interest, but are the essential complement to other cosmological studies, such as the Planck satellite mission currently in operation. Gaia addresses the big cosmological questions.

6 One of the many ways in which Gaia data will contribute is through discoveries of transient events – especially SuperNovae, the prime cosmological distance calibrators. These objects, being transient, require rapid ground-based follow-up, before they disappear for ever.

7 The UK, through the Cambridge Gaia data centre, has sole responsibility for the discovery and public release of Gaia transient discoveries. It is an example of UK leadership of an exceptionally high-profile international project.

8 Transient objects are found in both hemispheres, north and south, and so naturally require follow-up capabilities in both hemispheres. Access to the Isaac Newton Group is crucial.

9 A particular strength in follow up is automated telescopes, which can respond quickly. The UK’s involvement in the Liverpool Telescope, and the Faulkes telescopes, is of special importance here.

10 In addition to the manifest science impact, there is a huge potential for motivating the young. Linking the Gaia real-time science discoveries to school access to remote robotic telescopes means that school children can, and will, be able to make unique science discoveries as a natural aspect of their school lessons. Since Gaia will discover new interesting objects every few minutes, schools can schedule time well in advance, knowing there will be unique new discoveries which they will be the first to confirm and follow-up. School students can learn for themselves the excitement of real original science.

11 This project is feasible provided that access to telescopes is provided. If not, the Gaia educational potential will be lost to UK schools – very major preparatory efforts for this are underway elsewhere, particularly in France and Poland, in collaboration with the UK Gaia team. Astronomy manifestly has the highest public profile of all sciences, and correspondingly has an obligation to deliver real science, beyond pretty images. The opportunity exists, and only requires that the capability exists.

12 STFC’s focus on superb facilities delivered through ESO is manifestly sensible for the biggest projects. Scientific and educational/outreach requirements show that it is also essential to maintain breadth of access, both geographically and in scale of facility. This is particularly important noting the synergy between STFC major astronomical facilities, the UK’s investments in the European Space Agency, and the astrophysics-particle physics complementary approaches to understanding the nature of reality, through CERN/LHC and the astrophysical dynamics from Gaia.

13 UK science has excellence, and breadth. It will maintain this through balanced access to a range of facilities, appropriate to the range of technical requirements across the scientific spectrum.

This submission is provided by

Professor Gerry Gilmore

UK Principal Investigator, Gaia mission

Professor of Experimental Philosophy

Institute of Astronomy,

Madingley Road

Cambridge, CB3 0HA

16 February 2011