*Correction (8/01/08): This article originally identified the cost as $30 million.
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New approaches to space sail technology could give a much-needed push to interplanetary, and even interstellar, travel
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August 15, 2008
*Correction (8/01/08): This article originally identified the cost as $30 million.
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12 Comments
Add CommentPlease, are we that desperate to just throw mony down the drain to say in the New York Times we put a satellite in space that can go fast but we have no control of where it goes. Crack pot concept.
Reply | Report Abuse | Link to thisIf you are really interested in a practical solution look for near light speed propulsion engine now in development that will go 66,000,000 miles/hr and can be steered to what ever direction is desired. Realistic concept.
I really want to know why there isn't any sort of engine. If there are all these particles out there from the sun that can be repelled against then why don't we treat them like air and use the like we do in a jet engine. Clearly I am oversimplifying here but it seems to me that the suns of the universe have filled the cosmos with these particles for billions of years so they should be every where like the air in earths atmosphere.
Reply | Report Abuse | Link to thisearth has a magnetic field to deflect these particles, though.....
Reply | Report Abuse | Link to thisAd astra!
Reply | Report Abuse | Link to thisI think you are referring to a Bussard Ramjet
Reply | Report Abuse | Link to thishttp://en.wikipedia.org/wiki/Bussard_ramjet
Why isn't the concept of a continuous laser propulsion system from earth directed at the sail a viable concept? That way you would have a continuous source of outbound power beyond the range of solar winds and could even significantly increase the speed of the craft.
Reply | Report Abuse | Link to thisthe machine you are talking about is a Buzzard ram, it gathers ions and free atoms from space and accelerates them via a particle accelerator, the trouble is that this atoms are so disperse (acording to Sagan's Cosmos about one atom in 10 cubic centimeters, that is the avarage size of a grape handful), that you would need a collector dish in the order of hundreds of kilometers wide to get enough mater for a decent trust.-
Reply | Report Abuse | Link to thisI believe this kind of sails would handle about the same way as the old wind sails of yesteryear, where you position it in an angle that generates trust to the point you want to go to.
Reply | Report Abuse | Link to thisWhich kind of engine are you talking about? near light speed seems to be to hot to handle (radiation due to impacts, trouble looking beyond your nose
quote: "I really want to know why there isn't any sort of engine. If there are all these particles out there from the sun that can be repelled against then why don't we treat them like air and use the like we do in a jet engine." You are right, but the density is a million times lower, so any kind of airplane jet engine would not work.
Reply | Report Abuse | Link to thisFor goal #5: A sail with 1 gram per square meter?
Reply | Report Abuse | Link to thisCould that be done?
Why do you think we could not control the direction of such spacecraft?!! ... Very strange!
Reply | Report Abuse | Link to thisAlso, why do you need to precisely steer a spacecraft on a journey out of our solar system once you set the course once (which is basically away from the Sun)??!! Beats me... or probably you are clueless to the vastness of this cosmos and our insignificantly (in size and distance to near by stars/objects) solar system!
Even doubling or tripling the speed of Voyager 1, 2 - as these technologies promise as of now - would not make the possibility of reaching another star very likely! Get a clue man!
And ... a near speed of light propulsion engine?! Have I been knocked out and unconscious for the last decade?! ... So Strange!
I have invented a novel propulsion engine but it is in no way similar to the ion propulsion. It's an electro-mechanical engine, which means it converts electricity directly into mechanical force instead of using fuel. It's a novel concept and it's hard to explain how it works and creates thrust because some people (as I expected) told me it violates conservation of momentum. In theory yes but in practice I don't think so. I hope I will have a prototype of it fabricated and put to test soon. You may check it out on my website:
Reply | Report Abuse | Link to thiswww.hosseinnabipour.ca
-Hossein Nabipour, inventor of the first practical interstellar propulsion engine