EM Drive

[oOduffyOo 195]

A group at NASA’s Johnson Space Center has successfully tested an electromagnetic (EM) propulsion drive in a vacuum – a major breakthrough for a multi-year international effort comprising several competing research teams. Thrust measurements of the EM Drive defy classical physics’ expectations that such a closed (microwave) cavity should be unusable for space propulsion because of the law of conservation of momentum.

 

 

Das Konzept des EM Drives schwirrt schon seit einigen Jahren durch Labore. Anscheinend konnten kürzlich ziemlich bedeutsame Fortschritte gemacht werden, die hier mal erwähnt werden sollen. Aber zu aller erst: Wozu einen EM Drive und wofür braucht man das?

 

The applications of such a propulsion drive are multi-fold, ranging from low Earth orbit (LEO) operations, to transit missions to the Moon, Mars, and the outer solar system, to multi-generation spaceships for interstellar travel.

Under these application considerations, the closest-to-home potential use of EM Drive technology would be for LEO space stations – such as the International Space Station.

2015-04-19-010224In terms of the Station, propellant-less propulsion could amount to significant savings by drastically reducing fuel resupply missions to the Station and eliminate the need for visiting-vehicle re-boost maneuvers.

The elimination of these currently necessary re-boost maneuvers would potentially reduce stress on the Station’s structure and allow for a pro-longed operational period for the ISS and future LEO space stations.

Likewise, EM drive technology could also be applied to geostationary orbit (GEO) satellites around Earth.

For a typical geostationary communications satellite with a 6kW (kilowatt) solar power capacity, replacing the conventional apogee engine, attitude thrusters, and propellant volume with an EM Drive would result in a reduction of the launch mass from 3 tons to 1.3 tons.

The satellite would be launched into LEO, where its solar arrays and antennas would be deployed. The EM-drive would then propel the satellite in a spiral trajectory up to GEO in 36 days.

2015-04-19-010251Moving out from LEO, Mr. March, from NASA EagleWorks, noted that a spacecraft equipped with EM drive technology could surpass the performance expectations of the WarpStar-I concept vehicle.

If such a similar vehicle were equipped with an EM Drive, it could enable travel from the surface of Earth to the surface of the moon within four hours.

Such a vehicle would be capable of carrying two to six passengers and luggage and would be able to return to Earth in the same four-hour interval using one load of hydrogen and oxygen for fuel cell-derived electrical power, assuming a 500 to 1,000 Newton/kW efficiency EM Drive system.

While the current maximum reported efficiency is close to only 1 Newton/kW (Prof. Yang’s experiments in China), Mr. March noted that such an increase in efficiency is most likely achievable within the next 50 years provided that current EM Drive propulsion conjectures are close to accurate.

Far more ambitious applications for the EM Drive were presented by Dr. White and include crewed missions to Mars as well as to the outer planets.

Specifically, these two proposed missions (to Mars and the outer planets) would use a 2 MegaWatt Nuclear Electric Propulsion spacecraft equipped with an EM Drive with a thrust/powerInput of 0.4 Newton/kW.

With this design, a mission to Mars would result in a 70-day transit from Earth to the red planet, a 90-day stay at Mars, and then another 70-day return transit to Earth.

 

 Zusammen gefasst könnte diese Technologie herkömmliche Booster Raketen ablösen und somit die Raumfahrt um eine lange benötigte Antriebstechnolgie bereichern, Das Problem bei dem Design ist, dass es allem Anschein nach die Gesetzte der Physik speziell Newtons 3. Gesetz verletzt. Es gibt nämlich keinen Austoss von Material wie bei herkömmlichen Antrieben. Elektrische Energie wird direkt in Schub umgewandelt. Der Effekt ist allerdings jetzt schon mehrfach bestätigt worden und hält bis jetzt jeder Überprüfung stand. Wieso es funktioniert ist ein absolutes Rätsel. 

 

Dieser Antrieb würde die Erforschung des Sonnensystems in greifbare Nähe rücken. Statt 7 Monate zum Mars, wäre man nur 70 Tage unterwegs. Ein machbares Zeitfenser, völlig unabhängig von Planeten Konstellationen. Alleine diese Tatsache würde die Raumfahrt revolutionieren. Es kommt allerdings noch verrückter:

For the last three years, Dr. White’s team has been conducting experiments to find out whether it is possible to measure, with an interferometer, a distortion of spacetime produced by time-varying electromagnetic fields.

The ultimate goal is to find out whether it is possible for a spacecraft traveling at conventional speeds to achieve effective superluminal speed by contracting space in front of it and expanding space behind it.  The experimental results so far had been inconclusive.

During the first two weeks of April of this year,  NASA Eagleworks may have finally obtained conclusive results.  This time they used a short, cylindrical, aluminum resonant cavity excited at a natural frequency of 1.48 GHz with an input power of 30 Watts.

2015-04-26-182647This is essentially a pill-box shaped EM Drive, with much higher electric-field intensity, aligned in the axial direction.  The interferometer’s laser light goes through small holes in the EM Drive.

Over 27,000 cycles of data (each 1.5 sec cycle energizing the system for 0.75 sec and de-energizing it for 0.75 sec) were averaged to obtain a power spectrum that revealed a signal frequency of 0.65 Hz with amplitude clearly above system noise.  Four additional tests were successfully conducted that demonstrated repeatability.

One possible explanation for the optical path length change is that it is due to refraction of the air.  The NASA team examined this possibility and concluded that it is not likely that the measured change is due to transient air heating because the experiment’s visibility threshold is forty times larger than the calculated effect from air considering atmospheric heating.

Encouraged by these results, NASA Eagleworks plans to next conduct these interferometer tests in a vacuum.

 

 

In 4 auf einander folgenden Tests, wurden Lichtstrahlen gemessen, die anscheinend Einsteins Relativität verletzen. Sie waren nämlich langsamer als das Licht eigentlich sein sollte. Um Messfehler aus zuschliessen, werden demnächst Tests im absoluten Vakuum durchgeführt. Die NASA selber glaubt, dass ein Messfehler relativ unwahrscheinlich ist dennoch will man sich noch nicht festlegen, bis die Tests abgeschlossen sind. Könnte ein EM Drive die Raumzeit biegen? Im Juni werden wir mehr erfahren. 

 

http://www.nasaspaceflight.com/2015/04/evaluating-nasas-futuristic-em-drive/

[scratchy 535]

wieso muss ich bei solchen Stories immer direkt an den Rossi mit seiner kalten Fusion denken

[oOduffyOo 195]

Verstaendlich, es gibt jede menge quacksalber in dem bereich. Der EM drive hat jedoch wiederholbare Ergebnisse bei Tests produziert. Bis jetzt ist es noch niemanden gelungen, das Gegenteil zu beweisen.

[meinereiner 156]

bin zu faul den ganzen englischen text zu lesen. Wie weit ist denn dieser tolle neue antrieb?

Reine Laborversuche? dann dauerts ja immer noch ewig bis es tatsächlich brauchbar ist und ob es dann in brauchbaren größen auch funktioniert ist wohl auch noch nicht geklärt?