Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Coming up in January’s Physics World . . .

04.01.2008
The magnificent but mysterious snowflake. The beautiful snowflake is much more than an attractive seasonal occurrence. In fact, understanding how a snowflake grows is a complex problem of molecular dynamics, writes Kenneth Libbrecht, Professor of Physics at the California Institute of Technology, in January’s Physics World.

Everyone knows that no two snowflakes are identical to one another. That's because they all start out as a simple hexagonal prism - the most basic form of snow crystal - but then encounter a range of atmospheric conditions as they journey down to Earth.

It was two Japanese physicists who made early strides in our understanding of snowflake formation. Ukichiro Nakaya at the University of Hokkaido in the 1930s and Takehiko Gonda in the 1970s at the Science University of Tokyo found that humidity, temperature, air pressure and other conditions are the variables that determine the shape of a snowflake.

Kenneth Libbrecht writes, “Although no two crystals end up exactly alike, the six arms of a single crystal all travel together, so they all grow in synchrony, giving each falling crystal a unique and intricate structure with a recognisable symmetry.”

The conditions in the atmosphere dictate how water molecules are transported to the crystal but, because of the infinitesimal range of conditions, that makes it hard to simulate snowflake growth and explain how particular structures are formed.

Numerical modelling is now being used to reproduce the complex structures. The work is of particular interest to metallurgists as a better understanding of snowflake structures could profoundly affect the strength and ductility of their own final materials on a micro- or even nano-scale.

Libbrecht continues, “Beyond the intrinsic scientific questions, beyond the practical applications of crystal growth, and beyond the meteorological significance of atmospheric ice, we who ponder snowflakes are motivated by a simple and essential desire to comprehend the natural world around us.”

Also in this issue:

•Funding bombshell hits UK physics
•The physics of dance

Dianne Stilwell | alfa
Further information:
http://www.physicsworld.com/

More articles from Physics and Astronomy:

nachricht A 100-year-old physics problem has been solved at EPFL
23.06.2017 | Ecole Polytechnique Fédérale de Lausanne

nachricht Quantum thermometer or optical refrigerator?
23.06.2017 | National Institute of Standards and Technology (NIST)

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>