Will interstellar travel ever be reality?

[bdewoody]

As I get older it seems to me that interstellar travel will always be in the realm of Science Fiction. Bopping around the galaxy in sci-fi stories has always fascinated me and in my younger days I truly believed that some day us earthlings would be doing it. <br /><br />So what do you think our future will behold and if you do think trips to other stars (and back again) are possible how will the task be achieved?<br /><br />Now I would be happy to find out we will be masters of our solar system sometime in the forseeable future. <div class="Discussion_UserSignature"> <em><font size="2">Bob DeWoody</font></em> </div>

 

[yevaud]

Best case scenarios I have read are along the lines of what Eddie mentioned about Generation ships. But the scenarios I have read seem to believe that we will colonize a goodly part of this arm of the Galaxy, but it'll be in series of slow waves outwards at very sublight velocities (more like 30% light speed as an upper limiting velocity).<br /><br />Each colony would arrive at it's new destination and set up shop. Assuming it survives and thrives, several generations later, <i>it</i> sends out a Colony attempt.<br /><br />I think this is sensible and likely. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[qso1]

Same here, as I get older, and having gained knowledge on how actual space travel is done. I too get the idea that interstellar travel may be impossible. But then I remind myself that this is a condition of being an older adult. We see things less ideally and if I allowed myself to believe that interstellar travel is impossible. I couldn't write about it.<br /><br />I'd say the most accurate answer is that we don't know. But someday it is likely that we will one day journey to the stars. That day may be 100 or more years off, but its probably coming barring some global catastrophe.<br /><br />bdewoody:<br />So what do you think our future will behold and if you do think trips to other stars (and back again) are possible how will the task be achieved?<br /><br />Me:<br />This is exactly the idea I'm attempting to address in my own sci fi writings. Unfortunately, I'm a no name so this probably will never see the light of day and I can't reveal all of it for obvious reasons. I would venture this however, as its not really a new idea. I suspect early interstellar flight will be in multigenerational craft and the people on board won't be coming back. In addition to the time it takes just to reach a nearby star, if the journey is to a planet similar to earth. We may not want anyone returning to earth until medical science can assure no cross contamination will irrevocably damage earths environment.<br /><br />The destination will be a major factor. I doubt any human missions to planets that do not support life in ways we can deal with will be attempted. An example being planets around red dwarf stars where the planet may have an atmosphere, but the overall colors within the environment lean towards being reddish. And crews would wear EMUs anytime they are on EVA.<br /><br />In my younger days, I once thought we'd explore any and every planet found. Now I would say any planet not being earth like will be left to robotic exploration.<br /><br />Looking way beyond (1,000 or more years) in <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[qso1]

Post deleted by qso1 <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[qso1]

ZeroGeezus:<br />I imagine generations ships will convert themselves into factories once the destination...<br /><br />Me:<br />You betcha. The main difference is in my concept, the ship has major manufacturing capability from the time it leaves earth.<br /><br />In the image below, there is one lander, and a couple of manufacturing or factory craft that also land as part of the landing party if you will. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[qso1]

Another example shown on another world, this one orbiting a gas giant that itself orbits Alpha Centauri. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[strandedonearth]

I'd at least like to see an interstellar probe leave in my lifetime. Something that takes at least two or three HLLV loads of fuel for the departure burn, followed by nuclear-ion once the chem rockets are done. A solar sail wouldn't hurt either. Laser-riding from the Moon or Mercury for extra boost. <br /><br />Starting with the nearest stars, the Centauri system, of course. The probe would probably slingshot through the system in a matter of months at the speed it would probably have by then. Not sure where/which direction to send it next.

 

[vogon13]

IIRC, a line drawn form the sun to Barnard's star when continued on, passes fairly close to another star (can't remember the name) within 20 light years of earth.<br /><br />Interesting follow on mission perhaps.<br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[strandedonearth]

Hmm, gravity might bend the course too much for that, although a solar sail could probably correct that.

 

[vogon13]

Depends on how fast you are going past Barnard's star, and how closely you pass it.<br /><br />Presumably the necessary course deflection for any probe we might send that way would be appropriately close to Barnard's star.<br /><br /><br />For a mission to be interesting (ie. accomplishable in the lifetime of the folks who design build and launch the thing) be thinking craft velocity would be /> 0.4C.<br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[strandedonearth]

Hmm, 4.5ly at an average 0.4c would take 11.25 years, plus data return time (laser signal?) would bring the total to about 16 years. That seems quite reasonable, the timeline could probably be doubled and still fall within a young engineer's/astronomer's career, at least for the initial Centauri observations. That would give training to the next generation for the next stellar encounter down the line, er, trajectory.<br /><br />So would 0.4c do for the terminal velocity, after several years of nuclear-ion cruise, or should that be an average velocity? And just how much chemical and ion propellants would be needed to reach such speeds, for a probe massing how much? <br /><br />Perhaps we should start a 'Design a probe mission to the Centauri system' over in SB&T?

 

[qso1]

Don't know what happen to my images but I posted them yesterday and they still are awaiting approval. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[qso1]

Ah yes, thanks. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[vogon13]

Even my favorite, Orion Nclear Impulse Propulsion, won't be up to the task.<br /><br />Even with all the tweaks I can think of, Orion won't exceed 0.07 to 0.10C.<br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[lampblack]

<font color="yellow">Even my favorite, Orion Nclear Impulse Propulsion, won't be up to the task.<br /><br />Even with all the tweaks I can think of, Orion won't exceed 0.07 to 0.10C. </font><br /><br />You couldn't, like, use highly refined carbomite instead? Maybe give it a little boost? <div class="Discussion_UserSignature"> <font color="#0000ff"><strong>Just tell the truth and let the chips fall...</strong></font> </div>

 

[qso1]

Possibly, but only if they can mass produce antimatter in large enough quantities for the task. However, if one wishes to get really close to "C", even antimatter may not be up to the task. Theoretically, as you reach C, it takes all the energy in the known Universe to sustain or maybe exceed C.<br /><br />Anything well below C is probably doable with antimatter once the current technical and cost barriers are overcome. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[vogon13]

You want the lightest possible nukes with the highest yield per pound (and that retain their potency for the duration of the flight).<br /><br />Advances in material sciences and chemical explosives do help push today's nukes further up the graph/ Additionally, staging the Orion vehicle, and having nukes in fine gradations of yield will help the vehicle achieve 'starfall' as quickly as possible.<br /><br />Perhaps a 'continuous staging' pusher plate could be developed. Every nuke detonated might 'burn' a millimeter of 2 off the edge, and tune the mass/diameter of the pusher plate for optimum efficiency for the duration of the flight.<br /><br /><br />Acceptable mass fraction of vehicle to nukes is apparently around 90%. Hopefully, some of the improvements in vehicle performance can be balanced between speed and payload.<br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[spacefire]

what's up with all this primitive methods you people come up with?<br />we will travel through space at the speed of light, or very close to it. Ships will need are mass shielding devices and a good efficient impulse drive to push to such speeds.<br />Trips will last mere hours for the crew but on Earth thousands of years had elapsed.<br />If any way of travelling instantaneously can be found, it will make things even easier.<br />I just read "The Forever War" so I'm partkly inspire dby that book.<br /><br /><br /><br /><br /><br /> <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[bdewoody]

This is what I too expect that the reality of interstellar space travel will be. I suspect that a means of getting around the galaxy in a matter of days or weeks and then getting back to earth in time for juniors birthday will remain the stuff of Sci-Fi stories forever. <div class="Discussion_UserSignature"> <em><font size="2">Bob DeWoody</font></em> </div>

 

[spayss]

I find it amusing folks say we will travel at 40% the speed of light. Based on what? It's just grabbing a figure out of the air.<br /><br />We're down around a few ten thousandths the speed of light. Claiming we'll achieve 40% the speed of light is based on nothing.

 

[qso1]

spayss:<br />I find it amusing folks say we will travel at 40% the speed of light. Based on what?<br /><br />Me:<br />I'd have to say you are correct on this one, although I think some folks are basing it on what scientists say may be possible with certain types of advanced propulsion proposals such as Orion nuclear pulse can achieve a certain percentage of SOL based on the physics of nuclear explosions and the point of diminishing return one might reach when it would take too many nukes to be practical for going beyond the percentage of SOL that may be practical.<br /><br />Even these are merely educated guesses, but there has to be a starting point or frame of reference when engaging in discussions of such far off topics. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[yevaud]

No, not at all. The figure is based on known, but not quite yet achievable propulsion systems. As well, the figure of 30% (not 40%) is based on friction with the Interstellar medium, which means very high energy particles and phoptons impacting your ship. The 30% is from the theoretical limit on anything we know of that could possibly shield ship and crew from it. Beyond that, they'd fry like a fish from the Primary, Secondary, and Tertiary radiation. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[spayss]

That has nothing to do with manned spacecraft travelling at those speeds. <br />

 

[qso1]

Actually, it does. Particularly the part about people frying. There is something associated with SOL called the Lorentz scale or factor IIRC, which suggests as you get closer to SOL, the outer skin of a spacecraft would begin to get radioactive. SOL involving matter transferring to or becoming energy, this makes sense to me.<br /><br />The way around it is also theoretical. That would be materials designed to somehow keep the radiation from reaching inside the craft. Although I don't know if this radiationb effect affects just the outer portion of a vehicle or all of it.<br /><br />The other way around it is to build an interstellar craft out of a hollowed out asteroid but not hollowed to the point of a thin crust.<br /><br />The most likely way around it is limited speed which is why this does relate to manned spacecraft.<br /><br />All assuming some new discovery dosn't change the equation altogether. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[vogon13]

IIRC, the effect is caused by interstellar hydrogen atoms colliding with the vehicle.<br /><br />Induced cosmic rays, if you will.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>