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World’s largest science experiment brings science to life at Balloon Fiesta

Visitors enjoying the model of the LHC tunnel

Visitors enjoying the model of the LHC tunnel STFC

The University of Bristol's hot air balloon

The University of Bristol's hot air balloon STFC

Press release issued: 2 August 2012

The world’s largest science experiment is coming to the Bristol Balloon Fiesta, where visitors will be able to walk through a full-size replica of the Large Hadron Collider - the world's most powerful atom smasher - as well as having the chance to meet physicists involved in the recent Higgs boson discovery.

The hot air balloon’s place in scientific history will also be celebrated as live cosmic ray experiments are recreated in the skies above the festival, which takes place from 9 to 12 August 2012.

It’s the first time science has had such a strong presence at the festival, marking a year in which many UK researchers contributed to the work of the Large Hadron Collider (LHC) in Geneva to find the elusive Higgs boson particle, the key to explaining why matter has mass. It is also 100 years since since Nobel Prize winner Victor Hess showed the existence of cosmic rays by conducting his experiments in balloons.

Visitors will be able to see for themselves how the LHC is used to answer fundamental questions about the building blocks of the universe thanks to the interactive exhibit which is being brought to Bristol by the Science and Technology Facilities Council (STFC).

The replica tunnel is a 3.8m wide section of the actual LHC, which lies 100m beneath the Franco-Swiss border at CERN.

"This is a unique opportunity in terms of raising awareness of the amazing work that is being done at the LHC and the immense contribution that the UK is making to such big science. Never before has this message been showcased on such a large scale to such a varied audience in the UK", said Professor John Womersley, Chief Executive of STFC.

STFC has joined forces with the University of Bristol to celebrate the hot air balloon’s place in scientific history.

Victor Hess showed the existence of cosmic rays - particles coming from outside the Earth - by taking an electroscope in a hot air balloon and showing that radiation levels increased with altitude, rather than decreased. This showed that, instead of coming from the Earth as many scientists believed, cosmic rays were bombarding our planet from space.

In the 1930s fellow Nobel Prize winner Cecil Powell, who lived in Clifton and worked at the University of Bristol, used cosmic rays to make important discoveries about nuclear particles by also conducting experiments in balloons flown right up to the edge of the atmosphere.

This experiment will be recreated during the festival and the results communicated back to the ground where visitors can watch the live results.

Dr David Cussans, from the School of Physics at Bristol University, said: “Hess and Powell gave us our first glimpses into an invisible world, with apparatus that nowadays can be constructed by an amateur or school. I was inspired to study High Energy Physics by enthusiasm for measuring the unseen - I hope we can share some of this enthusiasm with visitors to the Bristol Balloon Fiesta.”

A-Level students have been involved in constructing the cosmic ray detectors as part of a summer placement funded by a Nuffield Foundation Science Bursary, which encourages students to work alongside professional scientists, technologists, engineers and mathematicians.

PhD students from the University of Bristol and the London universities who have worked with CERN on the Higgs boson discovery will also be on hand to answer questions and inspire the next generation of scientists.

Dr David Newbold, Head of the Bristol Particle Physics Group, said: “The fantastic discoveries at CERN this year have been all over the news, but I know a lot of people are not quite sure what a boson is, or why we've been trying to find one! I hope we'll have the chance to explain how our experiments work, and why we think they are important.”

Within the STFC tent at the Balloon Fiesta, there will also be hands-on exhibits such as a spinning ball particle accelerator, which shows how the 1,600 superconducting magnets within the LHC can control and accelerate a subatomic particle; and the cosmic ray detector, which allows visitors to see how frequently a subatomic particle passes through the equipment.

The festival, which is sponsored by Jones Lang LaSalle and is one of the largest outdoor events in the country, takes place at Ashton Court between Thursday, 9 August and Sunday, 12 August.

For more information about the Balloon Fiesta, visit

Further information

About the ‘LHC on Tour’

The ‘LHC on Tour’ is a travelling exhibition showcasing the LHC to highlight the United Kingdom’s role as a world leader in research and innovation. It has already visited 5 venues around the UK ranging from Central Hall in Westminster to the Jodrell Bank music festival. The exhibition is being run by STFC with the help of UK PhD and post doc particle physics students who have worked at or with CERN on an experiment on the LHC.

The remaining tour dates for 2012 are:

  • 9-12 August – Bristol Balloon Fiesta, Ashton Court, Bristol
  • 3-7 September – Upper Waiting Hall, Houses of Parliament (private event)
  • 30 September – Daresbury Mini Festival
  • 28 November-2 December – Senedd Building, Welsh Assembly, Cardiff

About ‘Cosmic Rays – 100 years of Discovery’

Cosmic radiation was discovered by Victor Hess, an Austrian-American physicist, 100 years ago and it has since been used to reveal many features of the subatomic world over the years. The exhibit at the Balloon Fiesta is linked to the HiSparc programme, which the University of Bristol is running with local schools to measure high energy particles which hit earth from outer space via cosmic ray detectors being built on their roofs.

To recreate Victor Hess' experiment, a team from the University and the equipment will be taken up to 10,000ft by Bristol Balloons Ltd just after dawn on either Friday or Saturday morning, depending on the weather. After taking off from the Fiesta launch field, they we be in contact with Bristol International Airport during the flight due to passing through controlled airspace. Following the descent, they will be hoping for a soft landing as the cosmic ray detector equipment is very fragile. The balloon being used holds 275,000 cubic feet of hot air with the basket carrying the detector equipment, nine passengers and the pilot Colin Hodges.

The Large Hadron Collider (LHC)

This amazing instrument accelerates two beams of subatomic particles to nearly the speed of light and then deliberately collides the beams into one another to recreate the conditions that existed just milliseconds after the Big Bang. Very sensitive detectors around the tunnel then record information about the types and properties of the particles given off, in the quest for the knowledge to answer some of the biggest physics questions around today.


The Science and Technology Facilities Council is keeping the UK at the forefront of international science and tackling some of the most significant challenges facing society such as meeting our future energy needs, monitoring and understanding climate change, and global security.

The Council has a broad science portfolio and works with the academic and industrial communities to share its expertise in materials science, space and ground-based astronomy technologies, laser science, microelectronics, wafer scale manufacturing, particle and nuclear physics, alternative energy production, radio communications and radar.

STFC operates or hosts world class experimental facilities including:

  • in the UK; ISIS pulsed neutron source, the Central Laser Facility, and LOFAR. STFC is also the majority shareholder in Diamond Light Source Ltd.
  • overseas; telescopes on La Palma and Hawaii

It enables UK researchers to access leading international science facilities by funding membership of international bodies including European Laboratory for Particle Physics (CERN), the Institut Laue Langevin (ILL), European Synchrotron Radiation Facility (ESRF) and the European Southern Observatory (ESO).

STFC is one of seven publicly-funded research councils. It is an independent, non-departmental public body of the Department for Business, Innovation and Skills (BIS).

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