Feeds

Cluster spies reformed shock wave

Straightened up, and flying right

Internet Security Threat Report 2014

Twenty years ago, physicist Vladimir Krasnoselskikh predicted that the Earth's bow shock wave, formed by the solar wind building up against our magnetosphere, would break and reform, just as waves on the ocean do.

Now, researchers using the European Space Agency's (ESA) Cluster constellation think they have seen the phenomenon in action.

The Earth's bow shock wave is analogous to the water pushed out in front of a boat as it moves. The earth is the boat, and the water is the solar wind. When the charged particles of the solar wind hit the magnetosphere, they slow down, and a charged barrier builds up at around a quarter of the distance to the moon; the shock wave.

In January 2001, the Cluster spacecraft were flying near the region of the shock wave in a tetrahedron formation, separated by roughly 600km. The researchers expected that since the craft were so close to one another, their readings would be almost identical as they approached the bow shock.

Instead, the readings were very different, showing large fluctuations in the magnetic and electric field surrounding each satellite. The data also showed "marked variations in the number of solar wind protons that were reflected by the shock and streaming back to Sun", ESA says.

According to Vasili Lobzin of the Centre National de la Recherche Scientifique in France, who headed this study, the readings are "the first convincing evidence in favour of the shock reformation model".

The discovery will be useful for researchers studying bow shock around distant celestial objects, where the phenomenon is also caused by exploding stars and the strong hot stellar winds from very young stars. Reforming bow shocks can also accelerate particles to extremely high energies and throw them across space.

Krasnoselskikh says the discovery of bow shock reformation here in our own solar system "is a unique opportunity to study distant astrophysical objects in the kind of detail not available in any laboratory". ®

For those who like to keep track of these things, the work was published in the paper, Nonstationarity and reformation of high-Mach-number quasiperpendicular shocks: Cluster observations, by V V Lobzin et al. published on 9 March 2007 in the Geophysical Research Letters. ®

Intelligent flash storage arrays

More from The Register

next story
Antarctic ice THICKER than first feared – penguin-bot boffins
Robo-sub scans freezing waters, rocks warming models
I'll be back (and forward): Hollywood's time travel tribulations
Quick, call the Time Cops to sort out this paradox!
Your PHONE is slowly KILLING YOU
Doctors find new Digitillnesses - 'text neck' and 'telepressure'
Reuse the Force, Luke: SpaceX's Elon Musk reveals X-WING designs
And a floating carrier for recyclable rockets
NASA launches new climate model at SC14
75 days of supercomputing later ...
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
prev story

Whitepapers

Designing and building an open ITOA architecture
Learn about a new IT data taxonomy defined by the four data sources of IT visibility: wire, machine, agent, and synthetic data sets.
The total economic impact of Druva inSync
Examining the ROI enterprises may realize by implementing inSync, as they look to improve backup and recovery of endpoint data in a cost-effective manner.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Business security measures using SSL
Examines the major types of threats to information security that businesses face today and the techniques for mitigating those threats.