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German Scientists Confirm NASA's Controversial EM Drive
MarkWhittington writes: Hacked Magazine reported that a group of German scientists believe that they have confirmed that the EM Drive, the propulsion device that uses microwaves rather than rocket fuel, provides thrust. The experimental results are being presented at the American Institute for Aeronautics and Astronautics' Propulsion and Energy Forum in Orlando by Martin Tajmar, a professor and chair for Space Systems at the Dresden University of Technology. Tajmar has an interest in exotic propulsion methods, including one concept using "negative matter."
Maybe this will be one that turns out not to be a scam...
Just thinking about this, how expensive would it be to create a small, simple satellite, with solar cells, some large LiPoly batteries, a transponder and an EM drive that fires up every time there is enough juice in the batteries to run it for a few minutes?
Sticking with the 50nN thrust level for 50W of input and assuming that a 1kg LiPol battery has 260Whr available (https://en.wikipedia.org/wiki/Lithium_polymer_battery), that is approximately 5hr of running time and assuming that the satellite is 5kg, there will be a 10nm/s^2 acceleration.
5 hours is 18,000s so there should be a delta-V imparted on the satellite of 1.8(10^-4)m/s which is tiny (I did say this is a pretty useless drive at the current time right now) but should be measurable or at least noticeable to its relative position to a control satellite that was launched along with it.
Mimetics Inc. Twitter
It appears to impart momentum to something without an opposite momentum imparted to anything else... you know, the basic concept of how every other propulsion system in the world works?
When you walk, your feet push against the ground, imparting a (tiny, relative to the mass of the Earth) amount of momentum to it at the same time that your feet impart momentum to your body.
When you sail a boat, the sails alter the momentum of the wind, and an opposite alteration is imparted to the momentum of the boat.
When a rocket engine fires, it releases exhaust with a lot of momentum going one way, and the rocket receives the momentum going the other way.
This model holds for any kind of propelling of anything. Even a flashlight projecting photons imparts a tiny, tiny bit of momentum to your hand, to your body, to the earth. Magnetic propulsion, chemical propulsion, ion propulsion... all of them operate on the principle of "we go this way, by making something else go that way".
The EM Drive appears to go one way without making anything else go the other way. It releases no exhaust, pushes against no solid or fluid, emits no photons, and interacts with no external magnetic fields. We don't know how it works (there are a number of theories, none of which are that widely accepted), and we still aren't 100% sure it does work (maybe it's still all experimental error... that becomes less likely with each independent verification, but extraordinary claims call for extraordinary evidence), but if it does work it does so in a way that is outside our current understanding of physics. That is a Really Big Deal.
One way or another, this is exciting!
There's no place I could be, since I've found Serenity...
As an added added bonus, such a drive would accelerate faster at a given thrust, because of the absence of reaction mass. Conventionally, acceleration steadily increases at a given thrust as reaction mass is ejected, with maximum acceleration being reached just before reaction mass is exhausted.
We can dream, can't we?
"Once you fire this husk of metal, it keeps going till it hits something. That can be a ship, or the planet behind that ship. It might go off into deep space and hit somebody else in ten thousand years. If you pull the trigger on this, you're ruining someone's day, somewhere and sometime....That means Sir Isaac Newton is the deadliest son-of-a-bitch in space."
"You saved 1968." - Ms. Valerie Pringle to the crew of Apollo 8