Anti-Matter Rockets

[barrykirk]

Not sure if this post belongs in Freespace or here.<br /><br />Anyway, the biggest obstacle to antimatter based rockets at this point from what I understand is the lack of a good source of antimatter.<br /><br />Just a couple of questions here pointed towards when do people think antimatter based rockets would be feasible.<br /><br />1) What research is being done towards developing antimatter production and storage facilities? Do we expect to have usable amounts of it within 20 years, 50 years, 100 years?<br /><br />2) What research is being done towards developing an antimatter based rocket engine? What do people think it would look like? What kind of thrust levels could be expected? And what kind of ISP could be expected?<br /><br />Yes, I know that with antimatter you could theoretically have a pure photon exhaust for really good ISP, but that would probably be a low thrust option for deep space operation.<br /><br />I'm talking about rockets that can go from the surface to LEO.<br /><br />Just throwing this out.

 

[PistolPete]

<font color="yellow">I'm talking about rockets that can go from the surface to LEO.</font><br /><br />First of all, using anti-matter as a propellant in the atmosphere is only a slightly better idea that using a Project Orion style rocket to launch satellites! Anti-matter drives are exclusively for deep space.<br /><br />Second, to attempt to answer your main question, as far as I know, all methods, both current and theoretical, are still too energy intensive to be practical, so it is unlikely to be a viable rocket fuel for the foreseeable future. <div class="Discussion_UserSignature"> <p> </p><p><em>So, again we are defeated. This victory belongs to the farmers, not us.</em></p><p><strong>-Kambei Shimada from the movie Seven Samurai</strong></p> </div>

 

[owenander]

all I know is it takes like billions of dollars to produce like 1/2 a gram or something<br /><br />I used to have the NASA weird projects website that had information on it

 

[barrykirk]

The problem with Orion going from surface to LEO is that it leaves large amounts of radioactive dust in the atmosphere.<br /><br />The half life of antimatter in the atmosphere is so low that it won't leave any radioactive material in the atmosphere. <br /><br />What happens when an antiproton impacts the nucleus of an atom other than Hydrogen? Does it make that atom radioactive? If it does, then that would be a problem.<br /><br />Is it possible to make sure that 99.99% of the atoms that are encountered by antiprotons are hydrogen atoms? If so, then the amount of radioactive material generated by a antimatter rocket should be miniscule.

 

[barrykirk]

That is true at present and the amount of energy released by "burning" 1/2 gram of antimatter is an infinitesmal amount compared to the energy required to manufacture it.<br /><br />But if the manufacturing efficiency could be raised to even 1%, would it make sense to use it as a rocket fuel?<br /><br />Who knows?<br /><br />At a certain manufacturing efficiency, I'm sure that it would be an optimal rocket fuel, assuming that other non rocket propulsion technologies haven't ecclipsed it by then.

 

[Boris_Badenov]

The biggest problem with Antimatter engines right now is not creating antiprotons, but storing them.<br /> Check out these sites; <br /><br />http://www.universetoday.com/am/publish/positron_drive_pluto.html<br />http://www.aiaa.org/aerospace/images/articleimages/pdf/NFFP.pdf<br />http://yarchive.net/space/exotic/antimatter.html<br /> <br /> And these sites for storage of Antimatter; <br /> http://www.matter-antimatter.com/antimatter_storage.htm<br />http://yarchive.net/space/exotic/antimatter_storage.html<br />http://www.thespacesite.com/space_antimatter_propulsion.html<br /> <div class="Discussion_UserSignature"> <font color="#993300"><span class="body"><font size="2" color="#3366ff"><div align="center">. </div><div align="center">Never roll in the mud with a pig. You'll both get dirty & the pig likes it.</div></font></span></font> </div>

 

[why06]

I wish....it was a half a gram cause I heard 1/34th of a gram could power 16 shuttle flights or something.... <div class="Discussion_UserSignature"> <div>________________________________________ <br /></div><div><ul><li><font color="#008000"><em>your move...</em></font></li></ul></div> </div>

 

[barrykirk]

The real question is, is this technology possible within the next 100 years?<br /><br />I agree that this is a long way off.<br /><br />And yes, there are three main problems.<br /><br />1) Generating the anitmatter economically.<br /><br />2) Storing the antimatter.<br /><br />3) Building a working antimatter rocket.<br /><br />

 

[barrykirk]

My bad, I just assumed that when protons annihilate with antiprotons it was similar to the electron positron reaction.<br /><br />After review some articles on the web, I can see that it is much more complicated than that.<br /><br />Still 40% of a whole lot of energy is a whole lot of energy.

 

[ittiz]

The gamma ray radiation from an antimatter rocket launching on the Earth's surface would be extremely destructive. An impulse drive needs to be developed before before using antimatter will become usable. Also antimatter is just a good way of storing energy in a high density manner. Making it is highly costly. Unless we can find a way to "magically" invert the quantum bits to transform matter to antimatter using antimatter won't be feasible.

 

[owenander]

I've come to understand that antimatter would not produce radiation and that's what is so great about it..<br /><br />It's the same method of getting energy as nuclear... The problem is you don't have endless hydrogen atoms to pull from you have to produce it.

 

[barrykirk]

An antimatter based rocket would produce plenty of radiation, what it has a good possibility is not producing any radioactive fallout.<br /><br />You run out of antimatter or you turn off the reaction and the radition levels should drop to zero immediatly.<br /><br />At least that is my understanding.

 

[qso1]

That it produces radiation won't matter as long as its operated in space. I don't see a real need for an endoatmospheric antimatter rocket other than that it could make possible, an engine the size of a thimble for a vehicle the size of a space shuttle. But the associated expense would probably make even that kind of engine unable to compete with chemical engines for leaving earths surface. Especially with potential endoatmospheric radioactivity hazards. <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>

 

[nyarlathotep]

"Anyway, the biggest obstacle to antimatter based rockets at this point from what I understand is the lack of a good source of antimatter. "<br /><br />We've got plenty of good albeit expensive sources of antimatter. What we lack is low mass containment. If your mass fraction is 0.0000001, your rocket isn't going to be a whole lot more useful than using a scuba bottle.

 

[qso1]

Another barrier is the sheer expense of producing it in any sort of useful quantity. <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>

 

[barrykirk]

Keep in mind that antimatter would have a much larger energy content per mass than any known chemical reaction.<br /><br />Your right if the containment bottle is high enough mass compared to the mass of the antimatter, it's not practical. But I don't know what the point of practicality is.