The University

Curiosity's radiation instrument calibrated in Uppsala

19 March 2013

Cary Zeitlin, Björn Gålnander and Alexander Prokofiev by the RAD at the The Svedberg Laboratory.

Ever since the space rover Curiosity set its wheels on Mars in August 2012, millions have followed it on NASA’s online video streams. A less known fact is that one of the rover’s instruments for measuring radiation was calibrated at a Swedish accelerator facility. Recently, American scientists returned to the The Svedberg Laboratory in Uppsala for new measurements of a similar instrument being sent to the International Space Station in 2015.

In January 2012, Dr Cary Zeitlin from the Southwest Research Institute visited the The Svedberg Laboratory for the first time, in order to calibrate Curiosity’s Radiation Assessment Detector (RAD) in the neutron research facility. Two weeks ago he returned together with eight other researchers for measurements of a new instrument developed for the NASA Johnson Space Center in Houston, Texas, for the International Space Station.

“We are calibrating two instruments that are used on space missions. One of them is as good as an identical copy of the RAD, which right now is gathering data onboard Curiosity on Mars”, says Cary Zeitlin. “The measurements are continuously sent back from Mars to Earth. To interpret the data from the RAD correctly, calibrations with high-energy neutron radiation are necessary, and that is why we have used the The Svedberg Laboratory.”

Critical components tested

Cosmic radiation consists of high-energy charged particles. These also produce neutrons in for instance the surface of a satellite or a spaceship, Cary Zeitlin explains. Today’s radiation shields are not enough to stop these particles which can disturb or damage a spaceship’s electronic systems. Since the costs of space launches are counted in the billions, every critical component or system must be tested against radiation beforehand.

“We need to know more about how the equipment responds to neutrons and other particles, and what levels of neutron radiation that occur in space. The latter is of great importance for any future manned expeditions to Mars”, says Cary Zeitlin.

The new instrument that the Southwest Research Institute and NASA are testing at the The Svedberg Laboratory is called ISS-RAD. The instrument will be sent to the ISS in 2015. The visit to Uppsala is primarily about collecting data which will then be analysed by German and American scientists. Thanks to the The Svedberg Laboratory's ability to produce neutron rays of different energies and particle flows, different tests can be coordinated which makes the work more efficient, Cary Zeitlin points out.

“At the The Svedberg Laboratory we use two neutron facilities, QMN and ANITA. Currently there is no other laboratory in the US or the rest of the world where we can perform these measurements. We also have a very good collaboration with the researchers and engineers at the facility; they are very helpful and competent.”

Increased capacity to meet demand

More than 600 users from 23 countries have visited the The Svedberg Laboratory over the last few years for experiments and radiation projects. Alexander Prokofiev, researcher at the laboratory, sees an increased need among companies and research groups to test electronic components against radiation.

“It can be a matter of both larger systems such as servers and communications equipment, as well as single memory units, processors and components for power electronics. By knowing how the electronics react to radiation, the manufacturers can fix the problems and create more reliable products.”

Some of the largest customers are Cisco Systems and Advanced Micro Devices (AMD), and new ones are added all the time. Apart from commissioned work, the lab also houses EU-financed projects for research and development in electronics irradiation, detector development and nuclear-physical data for neutrons.

“We are very interested in expanding our cooperation with academy and industry. There we could contribute much more than today with our knowledge about radiation and capacity to produce particle rays”, says Björn Gålnander, director of the The Svedberg Laboratory.

“At TSL we have a unique radiation facility which has great potential to grow.”