Although the Foton was only launched a week ago, the scientists are already very excited about the data they have received from their experiment, known as GRADFLEX (GRAdient-Driven FLuctuation EXperiment). The first results are qualitatively consistent with detailed theoretical predictions made over the past decade.
All liquids experience minute fluctuations in temperature or concentration as a result of the different velocities of individual molecules. These fluctuations are usually so small that they are extremely difficult to observe.
In the 1990s, scientists discovered that these tiny fluctuations in fluids and gases can increase in size, and even be made visible to the naked eye, if a strong gradient is introduced. One way to achieve this is to increase the temperature at the bottom of a thin liquid layer, though not quite enough to cause convection. Alternatively, by heating the fluid from above, convection is suppressed, making it possible to achieve more accurate measurements.
Although the early research involved ground-based measurements, it was suggested that the fluctuations would become much more noticeable in a weightless environment. Now, thanks to the Foton mission, the opportunity to test this prediction has come about, and the results completely support the earlier forecast.
“The first images from the experiment were downloaded to the Payload Operations Centre in Kiruna, Sweden, and received on Earth after only a few orbits,” explained Professor Marzio Giglio, leader of the team from the Department of Physics and CNR-INFM (Istituto Nazionale per la Fisica della Materia), University of Milan, Italy.
To the delight of the science team, the images visually support the theoretical predictions by showing a very large increase in the size of the fluctuations. Data analysis has also shown that the amplitude of the fluctuations in temperature and concentration greatly increased.
“It is a rare event when a space mission is able to confirm a theoretical prediction in such record time,” said Olivier Minster, Head of ESA’s Physical Sciences Unit. “These results are important because they are the first verification of the effects forecast a decade ago.”
“The availability of these images from the spacecraft has enabled us to change what we are doing so that we can optimise the scientific return from the mission,” said Professor David Cannell of the University of California at Santa Barbara (UCSB). “We will also have many thousands of images to analyse back in our labs after the experiment returns to Earth. This will keep us busy for quite a while.”
“It may be that our results will influence other types of microgravity research, such as the growth of crystals. Our research may even lead to some new technological spin-offs,” said Professor Giglio.
GRADFLEX is one of 43 ESA scientific and technological experiments on board the 12-day Foton-M3 mission. The mission is scheduled to end on 26 September, when the re-entry capsule will return to Earth in Kazakhstan. The onboard experiments will be returned to their home institutions where the data will be carefully analysed over the coming months.
Olivier Minster | alfa
Computer model predicts how fracturing metallic glass releases energy at the atomic level
20.07.2018 | American Institute of Physics
What happens when we heat the atomic lattice of a magnet all of a sudden?
18.07.2018 | Forschungsverbund Berlin
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences