Could a pure-electric laser-propelled space rocket be mere decades away?

  • Thread starter Thread starter kmarinas86
  • Start date Start date
  • Tags Tags
    Rocket Space
AI Thread Summary
A pure-electric laser-propelled space rocket could become feasible in the next few decades if advancements in energy storage technology occur. High energy density storage, surpassing that of current chemical rockets, would be essential for practical implementation. While solar sails are currently viewed as more viable, the concept of "light-fuel" offers intriguing possibilities for chemical-free refueling. The necessary power density for lasers would need to be extraordinarily high, potentially requiring nuclear-level energy. Despite the challenges, the theoretical groundwork suggests that such technology could eventually be realized.
kmarinas86
Messages
974
Reaction score
1
Could a "pure-electric" laser-propelled space rocket be mere decades away?

I know that there probably isn't a battery capable of making this practical yet, but if it were possible to store energy at a high enough density, wouldn't that make it theoretically possible to make a rocket that uses lasers powered by on-board batteries to accelerate a spaceship? I think in 20 or so years it's plausible that technology might get advanced enough for that.

Has this idea been entertained much, or are solar-sails seen as more practical? How dense would the energy storage have to be? I would assume that energy per mass densities much higher than chemical rockets would be necessary (unless if in the future this system means that there is a vast decrease of complexity of other systems involved in the regulation of the power plant). I think that ultimately it may prove superior. Imagine a spaceship that you could recharge with chemical-free refueling. The "light-fuel" could be transported at the speed of light, which you could not say for the fuel of a fusion rocket or an anti-matter rocket.

"Light-fuel" could even come in any color you wanted.
 
Physics news on Phys.org


Theoretically it would be possible, but the power density needed is DENSE. It would have to be at least nuclear if you want to get anywhere, and the laser (or even a flashlight) would have to be stupidly powerful, probably beyond all the flashlights and lasers currently on Earth put together. Force from light is extremely low.

Nevertheless, theoretically it's doable.
 
This is from Griffiths' Electrodynamics, 3rd edition, page 352. I am trying to calculate the divergence of the Maxwell stress tensor. The tensor is given as ##T_{ij} =\epsilon_0 (E_iE_j-\frac 1 2 \delta_{ij} E^2)+\frac 1 {\mu_0}(B_iB_j-\frac 1 2 \delta_{ij} B^2)##. To make things easier, I just want to focus on the part with the electrical field, i.e. I want to find the divergence of ##E_{ij}=E_iE_j-\frac 1 2 \delta_{ij}E^2##. In matrix form, this tensor should look like this...
Thread 'Applying the Gauss (1835) formula for force between 2 parallel DC currents'
Please can anyone either:- (1) point me to a derivation of the perpendicular force (Fy) between two very long parallel wires carrying steady currents utilising the formula of Gauss for the force F along the line r between 2 charges? Or alternatively (2) point out where I have gone wrong in my method? I am having problems with calculating the direction and magnitude of the force as expected from modern (Biot-Savart-Maxwell-Lorentz) formula. Here is my method and results so far:- This...
Back
Top