Opinion: A one-way ticket to Mars

An absolutely beautiful article.

I would go as far as to say that I would even be willing to go on a one way mission out to the Kuiper Belt or Oort cloud such as might be possible with the VASIMR engine being developed by the Ad Astra Rocket company among others.

Ultimately, to the extent that ever greater relativistic speeds can be reached such as in novel proposed but yet to be developed propulsion systems, similar one-way schemes could be used to visit the rest of the solar system and beyond.

Add to the possibility of future augmented human life expectancy as a result of medical intervention via anti-aging technologies, and I believe the public will surely go for the funding of such space programs or perhaps Manhattan Project style crash course efforts to develop the hardware and software to permit such journeys which obviously will be rather limited in their scope initially.

Some such propulsion schemes that do not involve any new physics beyond classical electrodynamics, Cold War era nuclear and particle physics, current materials science, current chemistry knowledge, and the like are as follows: 1) nuclear fission and/or fusion, or matter antimatter reaction powered ion, electron, photon, and neutrino rockets; 2) sun diver solar and or stellar sail space craft; 3) artificially generated photon beam or massive particle beam driven space craft via beam energy or massive particle reflection, absorption, and/or for use as fuel to energize propulsion systems; 4) novel yet to be thought of interstellar ramjet concepts; 5) electrodynamic-hydrodynamic-plasma drive systems; 6) magneto-electrodynamic-hydrodynamic-plasma drive systems; 7) electromagneto-hydrodynamic-plasma drive systems and the like; 8) fusion pellet steam runways; 9) fission pellet stream runways; 9) nuclear bomblet powered pulsed rocket craft that utilize yet to be developed pure minifusion bomblets that offer much improved specific impulse performance for fuel over the original Project Orion space craft that was the subject of once highly classified research by the U.S. Government during the late 1950s and early 1960s; 10) Steve Howes antimatter sail space craft; 11); Space craft ever so slightly accelerated by one side reflective Cosmic Microwave Background Sails; and 12) specific impulse optimized fission fragment drive space craft., and I suppose the list could go on.

For those readers who think the above concepts are pure fantasy or could not be realized, I recommend you do research within the pages and summaries of the numerous papers that have been presented at prestigious organizational conferences such as those of AIAA or the American Institute for Aeronautics and Astronautics and I would have proven my point.

One way manned space travel is an excellent way to go, however if we can work out return mission scenarios, and I think we can, then it becomes all the more palatable to the tax-payer (and maybe the astronaut!).

Regarding cosmic ray shielding for Mars bound craft and return missions, the solution is very simple, just set up a mini-magnetosphere around the space craft whether as a result of permanent magnets and/or electromagnets. Since we can deflect or bend the path of 7 TeV protons as in the soon to be operational Large Hadron Collider particle accelerator at CERN in Europe, we can certainly build a magnetic field system to safely divert solar cosmic rays which are on average several billion times less energetic than particles in state of the art particle accelerators.

Fusion rocket space craft could well reach relativistic velocities as great as 0.5 C. To see how, take the relativistic rocket equation: Delta V = C Tanh [(Isp/C) ln (M0/M1)] where Isp is expressed in units of C and is maximally equal to 0.119 C for nuclear fusion, and M0/M1 is the fueled weight to dry weight of the vehicle. If we assume that we will not need rocket fuel to slow the space craft down because some sort of reactive electrodynamic breaking mechanism would be used to decelerate the space craft such as a magsail, or a high current capacity superconducting drag inducing current loop and the like, than for an M0/M1 value of about 1,000 terminal velocities roughly equal to 0.5 C are possible, For an M0/M1 value of 100,000, terminal velocities equal to 0.866 C with a resulting relativistic gamma factor of gamma = 1/{[1 – [(v/C) EXP 2]] EXP (1/2)} become possible. At such a gamma factor, the crew could travel 100 light-years in 50 years ship time.

The number of stars within 100 light years is 14,600 stars. This is a lot of territory to explore with only good old fashioned reactionary propulsion rocket science. The opportunity is way to cool to miss out on.

I make the argument that virtually effectively unlimited gamma factors are achievable by matter antimatter rockets, especially anti-matter rockets that carry only their antimatter fuel components on board such as perhaps some form of neutral but yet to be developed anti-hydrogen atom based ice or other exotic similarly high energy density materials. I can provide the math for those who would like to see it.

Want to unite all of humanity as nothing has been able to do before? Then advocate for a national, multi-national, or UN type mandate to fund such bold missions. Face it, all of us techies and the general SCI-FI pop-culture loving teenagers, and 20 somethings will definately go for such a program.

Wrong, sorry. If you are only traveling 0.5C it would take you 200 years to travel 100 light years, not 50 as asserted. Is the rest of your math correct?

Hi Dana;

If one is traveling at 0.866 C, then the relativistic time dilation is obviously 1/{[1 - [(v/c) EXP 2]] EXP 1/2} = 1/{[1 - [(0.866/c) EXP 2]] EXP 1/2} = 2. You can work through the math your self to prove this.

The distance covered in 50 years ship time or in 100 years Earth time at a ship speed of (0.866 C) is (0.866 )(100) = 86.6 light years.

The ship will effectively appear to its crew members to be traveling faster than C due to relativistic time dilation. In other words d r(x,y,z)/dt = v(x,y,z) with respect to the ship’s reference frame is effectively equal to 86.6 LY/50 years = (86.6)/(50)C.

I made a slight math error, but I stated that “For an M0/M1 value of 100,000, terminal velocities equal to 0.866 C with a resulting relativistic gamma factor of gamma = 1/{[1 – [(v/C) EXP 2]] EXP (1/2)} become possible. At such a gamma factor, the crew could travel 86.6 light years in 50 years ship time.” which is the same as 100 years Earth time. Thus, in one hundred years Earth time, the ship would travel 86.6 Lightyears, not 50 light years, that is once the ship reached 0.866 C. Note that with a constant acceleration of 1 G, ship’s reference frame, the ship should be up to speed roughly one year, so that the additional passage of time for the ship including acceleration and any deceleration at 1G and -1G respectively will be negligible.

As for the rest of the math, it is indeed correct.

As for the equations of relativistic time dilation, they pass muster even with the most sophisticated measurements. Particle accelerators could not work is special relativity was not valid. The life time of muons produced within the Earth’s atmosphere by cosmic rays is greatly lengthened beyond the their mean life time of about 2.2 microseconds and thus the reason why the muons can be detected on Earth even after having been formed a dozen or more kilometers above the Earth’s surface.