Posted on 02/12/2017 7:07:41 PM PST by 2ndDivisionVet
The last man who walked on the moon has already passed away. Will there ever come a time when another person gets to be credited with the honor of walking on any part of the universe other than Earth?
Space is the ultimate destination. And it’s been 30 years since that fateful moon walk which, sadly (and maybe disappointingly), has yet to be repeated. We’ve been hearing and constantly talking about going to Mars. But until now, it’s still just talk, though there are concrete plans on the way.
To make the trip to Mars (or other planets or stars) a reality, we have to develop the needed technology that can cut travel time significantly. And that requires an effective propulsion system. There are a few experimental systems in the works. But whether these systems will eventually be built and used on manned spacecraft remains to be seen.
Antimatter
Antimatter is made of antiparticles and is known to have the highest energy density among any of the known substances. If it can be used as fuel, it can potentially provide the most efficient propulsion system, capable of converting up to 75% of its mass into thrust energy.
According to the NASA Institute for Advanced Concepts (NIAC), ten thousandths of a gram of antimatter will be sufficient enough to send a spacecraft to Mars in just 45 days. As infinitesimal as that amount is, however, creating it is the main problem.
Right now, antimatter can only be created using particle accelerators, and the amount created is far too small to be usable. If we can somehow find a way to create more, then maybe an antimatter engine can be built in due time.
Fusion
Fusion attempts to replicate the sun’s power by heating fuel to super-intense temperatures until atomic nuclei fuse and produce more energy. Fusion power can be achieved in two ways — continuous fusion and pulsed fusion.
Continuous fusion is dependent on output from a fusion reactor. It’s something that scientists have been attempting to develop for decades but up to now have remained unsuccessful.
Pulsed fusion involves regulated or controlled detonation of a small fusion bomb to create thrust. Pulsed fusion is more feasible, but ironically, it is more unacceptable because detonating a fusion bomb, even if it’s a controlled process, will likely violate nuclear test bans.
Ion Drive
The ion drive thruster works by ionizing (giving a positive or negative charge) an unreactive fuel molecule, then using an electric field to accelerate it from behind. While the thrust generated is low — meaning the engine acceleration is slow — an ion engine is ideal for long-range missions because it can theoretically deliver thrust that’s 10 times more than what conventional fuel can provide.
This technology has already been used, most notably by the Dawn spaceprobe which is presently orbiting around dwarf planet Ceres. NASA is presently working on new systems such as the NASA Evolutionary Xenon Thruster (NEXT) and the Annular Engine.
Photonic Propulsion
In contrast with conventional propulsion methods — firing propellant in the opposite direction that a spacecraft wants to go — photonic propulsion will make use of an array of lasers that will be fired at a spacecraft to send it into space. This means there’s no need for fuel that contributes added weight. And because the spacecraft is lighter, it can accelerate much faster with less friction, and reach higher speeds than previously possible.
Theoretically, this technology will allow a spacecraft to reach 1/4 the speed of light in only a matter of minutes, then travel at nearly 174.3 million miles per hour. At this rate, it can supposedly reach Mars in as little as 30 minutes.
The technology is being developed by University of California Santa Barbara scientists led by Professor Phillip Lubin.
Plasma
Similar with the ion drive, but with a slight twist. Instead of using nonreactive fuel, electrical and magnetic currents are used to accelerate ions (charged particles) in plasma to produce thrust.
The most powerful plasma rocket prototype is currently being developed by the Ad Astra Rocket Company in Texas. It’s known as the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) and will theoretically be able to send a spacecraft to Mars in as little as 39 days.
Solar Sails
A solar sail works by catching photons (particles of light) and having these photons push the sail to propel a craft forward. Ideally, a spacecraft with a solar sail that’s big enough can catch enormous amounts of photons, enough to push a craft at amazing speeds without the need for fuel.
The feasibility of this concept has already been proven in 2010 by Japan’s Interplanetary Kite-craft Accelerated by Radiation Of the Sun (IKAROS) project, and last year by the LightSail project.
The challenge with solar sails is that as it moves farther away from the sun, the weaker its thrust becomes. This basically limits its use to cosmic destinations that are not too distant from the sun.
Different technologies and different capabilities all directed towards one goal – to bring us to space. Let’s sit back and observe while the race to build the best propulsion system rages on.
Were those guys ever found?
I don't believe so. I think they're still out there. :)
Seriously, at least in the original TV series, they never permanently made it back to earth. However, in two episodes I recall, they did manage to find their way there momentarily, Will, by himself in an old B&W episode, and, in one of the later color episodes, the entire crew, only it was 1940s Earth and so they left, under hostile pressure from the frightened townspeople.
From my experience on submarines...
The first two weeks are the most emotionally charged as you leave home, followed by the 2 weeks before you get back to home.
The rest of the tour is crazy free
There are too many reports by solid witnesses to reject the notion of interstellar or interdimentional visitors out of hand. People are seeing things that do not fit conventional wisdom.
The thing is time slows down almost to zero for those on such a Light speed ship...it’s been measured that velocity effects subjective time for the given object(time slows down relative to stationary observers). So while at light speed traveling to a destination, time will seem not to pass at all but when decelerating...thousands of years will have passed on Earth but perhaps only a few months will have passed on the craft. The trick will be designing systems that can accelerate the ship and de-accelerate at the precise fractions of eternity so that a ship doesn’t over shoot its mark during “timelessness” mode. In other words....in trying to reach Alpha Centauri at the speed of light, a mistake is made and instead A. Centauri, the ship goes to the opposite side of the galaxy before anyone on the ship gets a sense that perhaps too much time/distance has gone by.
So aging won’t be an issue for persons on such craft, it will be for us on Earth!
It would take 8 to 10 years round trip to power up to get the A centauri, power down, explore a bit, then power up, the de-accelerate down. 10 years will have passed for us, several months plus exploration time(1-2 years) will have passed for them. The need for mapping will be huge as the travellers’ visual perspectives will have changed as they will see what Sol’s system will look like in relation to other known stars and constellations.
It already is possible, just not from Earth.
Funny, I started searching a bunch of different sites, thinking “where are they messing up? OB has a different number! How can these sites be getting it wrong!”
Everyone misses a putt once in a while!
FReegards!
he didn’t mention NASA’s new emdrive. Interestingly this is a warp drive.
he didn’t mention NASA’s new emdrive. Interestingly this is a warp drive.
Thanks- your pictorial sums up what I thought when I saw this last night
Humans thirst for knowledge is greatest achievement, building blocks, governments cannot quench - might take or co-op, but never quench.
Will happen in my lifetime, unknown but the dreamer says I hope so.
From first flight to jet propulsion was 50 years give or take, does not take a rocket scientist to see opportunities in the future for space travel
We will if we want to hard enough. Interstellar travel does not necessarily mean rewriting the laws of physics.
Yes, faster-than-light travel may or may not be possible. We can still get to the stars, if we accept a journey that may take a long while, as in generations. There are lots of SF stories covering methods: hibernation, colonies that take generations to get there, etc.
We can send off automated probes to all the nearby stars, which can explore any habitable ones, send back signals by laser as to what they find, and start the process of setting up a colony.
Um... NO... Two words... Cosmic Radiation. You cant get Humans to Mars without them being dead by the time you get there... unless you have a rocket with 18 inch thick lead walls... which....um... last time I checked are a bit heavy.
WOW..sounds like a plan...I am just a down to earth mechanical engineering, using Newtonian physics. I am clueless on theory of relativity. Many thanks for taking time to explain.
Thanks for the explanation, but it is way over my head, since all I know is Newtonian physics.
Piece of dust or two would kind of ruin your day, as well.
Though, drives like these discussed would be excellent to get raw materials to Mars well in advance of any colonists.
Reaching the stars is just a dream.
Make the best out of our world and we won't need to go elsewhere. We still need to build that wall!
Heh.....the round the world trips with jet bombers with time devices exactly synchronized with devices on the ground showed that the plane’s clocking devices were several seconds slower than the ground devices at the end of the trip. Apparently it was a mathematically expected result should the theory be valid. So a relativity expert I am not but I get the concept...Time goes slower for an object the faster it if travels towards the speed of light.
If we learn how to fold space-time, maybe.
It probably would have worked if the center fuel tank part had jettisoned as planned.
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