News for hackers. Stuff that matters.

A comment on Magnetoplasma drive could make Mars transit take 39 days?. Parent comment

Re:Magnetoplasma drive could make Mars transit take 39 days? by a_crc on Thursday August 20, 2020 @02:47PM (#24227009)
It's a lot of solar panel. A quick search gives us a figure of 220 watts of power per square meter of space based solar panel. This would mean a 200MW solar collector would need to be almost a million square meters in size. For reference that would be a square the length of 155 NYC city blocks on each side.
[ Parent | on HN ]
Re:Magnetoplasma drive could make Mars transit take 39 days? by SECProto on Thursday August 20, 2020 @03:13PM (#24227417)
> A quick search gives us a figure of 220 watts of power per square meter of space based solar panel. This would mean a 200MW solar collector would need to be almost a million square meters in size. For reference that would be a square the length of 155 NYC city blocks on each side.

200MW/(220w/m2) gives us an area of 1,000,000m^2, a square 1000m on each side.

(side note: a NYC block isn't a very good length reference - they vary[1] from 250ft to 750ft depending which direction you're measuring. So the square would be 4 to 12 blocks on each side)

[1] https://streeteasy.com/blog/how-many-nyc-blocks-are-in-one-m...

[ Parent | on HN ]
Re:Magnetoplasma drive could make Mars transit take 39 days? by api on Thursday August 20, 2020 @03:11PM (#24227400)
Hmm... or maybe some smaller panels plus a really enormous and very very thin reflective collector for concentrating solar. Keep in mind that things can be very thin in space.

It would still weigh a lot though, and heat would be a major issue. You wouldn't want to melt the solar panels.

This would require someone much more knowledgable to determine if it's feasible.

Edit: I wonder if you'd get some amount of solar sail effect in addition to the plasma rocket? Of course this would help you one way and hurt you the other way.

[ Parent | on HN ]
Re:Magnetoplasma drive could make Mars transit take 39 days? by codeduck on Thursday August 20, 2020 @03:12PM (#24227404)
A million square metres is one square kilometre. It could be built but it would be heavy. A circular sail with a radius of just over 600 metres would do it.
[ Parent | on HN ]
Re:Magnetoplasma drive could make Mars transit take 39 days? by chasd00 on Thursday August 20, 2020 @06:20PM (#24229698)
wouldn't a million square metered be a megametre and not kilometre?
[ Parent | on HN ]
Re:Magnetoplasma drive could make Mars transit take 39 days? by codeduck on Friday August 21, 2020 @04:17AM (#24233061)
no. 1000m * 1000m = 1000000m^2 or 1 km^2
[ Parent | on HN ]
Re:Magnetoplasma drive could make Mars transit take 39 days? by jcims on Thursday August 20, 2020 @03:24PM (#24227558)
That's if it's illuminated by the sun. Blast it with a 500MW space-based laser and you'll up the tempo.
[ Parent | on HN ]