Invisible particles vibrate on Researchers’ Night
The mission of the Rosetta probe ends on the last day of September, and researchers will reveal particles invisible to the naked eye. It’s Researchers’ Night at the Helsinki Observatory.

Our environment is full of particles which are invisible to the human eye, and we barely even know they’re there. These very same particles – and much rarer ones – can be created with colliders and detected with sensors, the largest of which are located at CERN in Switzerland.

Physicists will introduce this mysterious but measurable world to the audience at the Helsinki Observatory on 30 September between 17.00 and 20.00, when approximately 300 European cities will celebrate Researchers' Night.

“We will expose our silent partner-particles with a cloud chamber,” explains Terhi Järvinen from the University of Helsinki’s Helsinki Institute of Physics.

From cloud chambers to CERN

Research in particle physics is no longer conducted in cloud chambers, but they can be used to visualise ambient radiation all around us. For example, the Higgs boson, discovered in 2012, is so rare that it would have been impossible to detect with instruments such as a cloud chamber.

“Honestly, the Higgs boson is such a heavy particle that earlier particle accelerators would not even have been capable of creating it,” says Järvinen.

Even today, particle physics research is largely based on observing the trajectories of charged particles and identifying particles such as electrons and muons through a range of measuring methods.

 “The particles are visible as tracks of different thicknesses and shapes in our cloud chambers. Radiation is generally invisible to the human eye, but the cloud chamber reveals some of it,” Järvinen explains.

Many pioneering theories in particle physics predict the existence of hitherto undiscovered particles, and new particles need to be found to explain many of the phenomena we observe in the universe. The Helsinki Institute of Physics is part of the effort to find such particles.

The European Organisation for Nuclear Research, CERN, will broadcast a video programme entitled “CERN Control Centre. The room from which all CERN Accelerators are driven” at 19.00 Finnish time on 30 September. The 45-minute broadcast can be viewed at the Observatory.

Last moments of the Rosetta probe

The last day of September also marks the end of the Rosetta comet mission, and the Rosetta probe will slowly be guided to the surface of its comet at which time it will take a final set of measurements. This heralds the end of the probe’s two-year investigation of comet 67P/Churyumov–Gerasimenko.

The Rosetta probe will hit the comet’s surface on Friday 30 September at approximately 13.30 Finnish time. The probe will send out its final observations during its approach and transmit them to Earth in real time.

 “Rosetta has been a successful research mission with a robust Finnish presence. It is particularly exciting for us to watch its final moments, as the Finnish Meteorological Institute participated in the design and construction of six of the pieces of equipment on the probe. The equipment has functioned as expected and we have gained a great deal of data,” says Riku Järvinen, research scientist in planetary science and space physics at the Finnish Meteorological Institute.

The European Space Agency (ESA) will livestream the event. The time of impact is estimated to be 13:30 Finnish time.

Space storms and Northern lights illuminate Researchers’ Night

The Rosetta probe is also part of Researchers’ Night at the Observatory, as researchers from the University and the Finnish Meteorological Institute track the probe’s approach to the comet's surface. In addition to this, Researchers’ Night features amazing videos about the Sun and a tutorial on how to forecast space weather.

Visitors will also learn, among other things, about coronal mass ejections. What do they have to do with the aurora borealis?. And what would a space storm look like? Find out by watching the fascinating animations generated by the world’s most precise space simulator, Vlasiotor, depicting the Earth’s near space as it weathers solar winds. An electric sail tether, thinner than a human hair, is also on display.

Spend the night with researchers

Researchers’ Night will be held on Friday, 30 September 2016 simultaneously at approximately 300 cities around Europe. In Finland, the event is being organised at 13 different locations.

The University of Helsinki will arrange events at Think Corner, the Helsinki Observatory and the Lahti University Campus. The University’s researchers will also participate in the programme at Heureka, the Finnish Science Centre.

The Helsinki Observatory is located at Kopernikuksentie 1. The Observatory’s doors will be open from 17.00 until 20.00, but please note that the facilities are quite small. Please join us!

The evening’s happenings are all part of the Researchers’ Night event, which has received two-year funding from the European Union’s Horizon 2020 programme’s Marie Skłodowska-Curie actions, intended to fund European research and innovation projects.

Read more:

Researchers’ Night programme at the University of Helsinki

Finnish Researchers’ Night website

The Rosetta probe witnessed the awakening of the icy comet