Comments on: Ion Thrusters Come of Age for Interplanetary Spacecraft

By: Usarian

Usarian — Fri, 25 Sep 2009 14:36:58 +0000

I don’t think VASIMR is ION in any way.. no expert, but a big fan of the project. It uses lasers and rf emitters to superheat matter into plasma. Plasma is repelled by all magnetic fields, so really strong magnets are used to contain and compress the plasma and force it out at high velocity. It can’t go as fast as ion engines, but it has a much stonger thrust and doesn’t take years to speed up, and goes significantly faster than chemical thrusters and doesn’t use up the fuels anywhere near as fast. BTW, that 39 day trip to Mars actually IS VASIMR with their most expensive and (unfortunately) least likely configurations, not Ion. VASIMR requires nuclear power to be viable, but a tiny one has been designed to run off the space stations solar power in short bursts for proof of concept basically.

By: DocM

DocM — Fri, 18 Sep 2009 21:23:23 +0000

The engine Bolden mentioned @Congress that could make a 39 day Mars trip is VASIMR. The author left it open in the last paragraph.

Also; VASIMR is a plasma rocket, not an ion engine in the sense of NEXT or the others which use electrodes to accelerate the fuel mass. VASIMR uses superconducting magnets to creat fields that accelerate the fuel mass, so no electrode erosion which is a big problem with ion thrusters.

By: Dan

Dan — Sun, 13 Sep 2009 21:03:27 +0000

So N years from now, will astronomers in solar systems N light years away be able to detect these various xenon ion trails crisscrossing our solar system?

Can you imagine their headlines? “Those alien beings bombarding us with bad television now have space travel!”

By: Henry Wysmulek

Henry Wysmulek — Sat, 12 Sep 2009 12:49:15 +0000

Nasa might as well pack it’s bags and close the doors under this current president1

By: Mike

Mike — Fri, 11 Sep 2009 20:30:57 +0000

Ion thrusters or even full blown warp drives won’t alone make humanity a space faring race… not in the sense it was once the seafarers that discovered new lands.

It takes both vision and courage to commit to a long term space effort, something that our current crop of leaders seem far too timid to dare. We are all very busy building military machines, inventing noxious germs in secret labs and basically just conspiring against our common good for any such noble undertaking.

If there are alien races out there, you can bet they are hoping that the trash stays put, on Earth.

…

By: Carter

Carter — Thu, 10 Sep 2009 23:31:23 +0000

No thruster produces any kind of meaningful ‘lift’ in outer space. Perhaps many readers do not have the benefit of a high school physics course, but I lobby that this should not dissuade Discover Magazine’s blogs from using accurate terminology. In this case, that would be ‘counteract the force of gravity on a pound coin’ instead of ‘lift a pound coin.’ And in the following sentence, it is desirable to point out that the same amount of force is generated but due to the near lack of gravitational forces and matter to produce friction on the spacecraft, acceleration is quite slow but continually increases the velocity of the spacecraft. This would dispel any confusion with the analogy of the pound coin.

By: YouRang

YouRang — Wed, 09 Sep 2009 14:29:10 +0000

Yep ion thrusters have been just around the corner since the 60s. The problem is: Ion thrusters are the RIGHT tool; whereas Chemical thrusters (and atomic bomb thrusters even more so) are the BIG TOOL (as in Tim tool man Daley’s poster–”Now THAT’s a Tool.” )

By: Romeo Vitelli

Romeo Vitelli — Wed, 09 Sep 2009 00:00:21 +0000

Is it just me or has ion propulsion been just around the corner since the 1960s?