The Swarm Constellation Will Look Inside the Earth

Roland Piquepaille writes "Among six Earth Explorer candidate missions, the European Space Agency (ESA) has chosen a 'Swarm' of satellites to look inside the Earth and to do the best survey ever of the Earth's geomagnetic field. The mission, scheduled for launch in 2009, will consist of three satellites released by a single rocket. Two will fly side-by-side 450 km above us while the third one will cruise at an altitude of 530 km. In "ESA to probe Earth's magnetic field," the Register also looks at this future mission which will lead to a better analysis of the Sun's influence in our solar system. More details and illustrations are available in this overview."

Comments

Re:If for no other reason

[Anonymous Coward]

I'm a geophysist, not a pilot. We normally use IGRF. It has the history of the magnetic field as well as future predictions. It's very accurate and is updates at every five years. That sounds the same as what you are talking about, but you can make a new map every year that's much more accurate than last years, even without a new model. The drift of the field isn't random.

Pilots only need a very gross measurement of magnetic field. They really only care about the field coming from the earth's core. We measure the field coming from the core and the rocks then remove the core's field. The field from the rocks is much smaller, but can tell you a lot.

Re:If for no other reason

[Discoflamingo13]

For civilian applications (which lack military precision), and in the event of GPS failure, magnetic heading will always be there to fall back on.

Re:If for no other reason

[Discoflamingo13]

Magnetic headings are usually the first fallback during severe weather conditions, and avionics companies want the maps of the variations to be as accurate as possible. For verification purposes, most companies won't rely on predictions (regardless of how accurate they most certainly are) - they want to see hard measurements based on the most current data. This is largely because these decision are made by businesses, and not science firms - but it doesn't make your point any less valid.

Re:If for no other reason

[Discoflamingo13]

Chances are more than likely that during this time, planes will be grounded until the weather is clear for the duration of the flight. New magnetic variation maps are drawn once the field stabilizes, and aviation goes on. Planes in communication with a control tower can manually enter a makeshift heading - this happens during some heavy electrical storms, or when the magnets fail. The problem is flight over unpopulated areas (like the ocean).

Earth's magnetic field is starting to flip?

[garyebickford]

Some scientists think the Earth's magnetic field is preparing to flip again, which it does every so often. Apparently when this occurs, it is preceded by a period of local variations - mini-poles showing up all over the planet. This system could be invaluable in tracking this process.

Also, according to this article and others, the field has decreased 10% over the last 150 years. This has left some satellites vulnerable to damaging radiation.

Other links:
Sun's rays to roast Earth as poles flip"
The Sun Does a Flip
Quick flip of Earth's magnetic field revealed