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>Deep Space1 put out 90 millinewtons of thrust, this is putting out around .9 Newtons of thrust with an ISP of >6000.

Could we get this past 10,000-20,000 ISP with around 100 Newtons of thrust? A technology definitely worth investigating.

What the hell did you just say?!

English Please?

OK.
ISP is specific thrust:
This is: thrust (pounds, for instance) for a time (seconds) per mass of propellant (kg, for instance).

So, Deep Space 1 has Isp of 3,100:
That's a thrust of about .1 newton (or .022 pounds) for 310,000 seconds for each kg of propellant.

Thus, (for instance - numbers not exact) the earlier Deep Space 1 100 kg of propellant will run for 30 million seconds
or more than a year with a thrust of less than an ounce.

It has run for at least 40 million seconds or used 127 kg of propellant.

Long-distance interplantary probes can use low thrust for long periods. They minimize the propellant mass (for efficiency) and maximize the acceleration of the propellant (no 'burning' reaction, only an electrostatic charge which accelerates an ion).

The ion engine is like the solar sail concept in that it uses low power over a long time. A spacecraft of small mass can accelerate over time.

For the example above, a 100 kg craft for 450 days would get to more than 90,000 miles per hour. (but would typically spend half the travel time decelerating).