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Comments

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This Satellite Could Be Beaming Solar Power Down From Space By 2025

mark99 Re:Nope. (245 comments)

An ion thruster I suppose would do the trick. Of course it would run out of Xenon after awhile, but ion engines have the highest fuel to force ratios short of a solar sail.
Actually come to think of it I am not sure it is much of a problem. If you were in a geosynchronous orbit, surely the solar pressure would push you away half the time, but push you back the other half, right?

1 year,22 days
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This Satellite Could Be Beaming Solar Power Down From Space By 2025

mark99 Re:Nope. (245 comments)

Agree with the poster. I figure solar cells in space will not trump solar cells on the ground until we dramatically lower the cost of delivery to orbit. At the moment we SpaceX is quoting 4300 USD/Kg to orbit on a Falcon 9 (1.1 - still waiting on maiden flight Sept5), and maybe down to 1200 UDS/Kg for the not yet built or demonstrated Falcon Heavy. And that is to LEO, Solar Cells probably need GTO which is about twice as expensive. I can't imagine a space based array can be competitive at those prices.
Now if someone built a rail-gun based launcher, then maybe it could make sense.
And as AC mentioned, we are in the midst of a ground based solar cell revolution right now. Very cool...

1 year,22 days
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Microsoft Needs a Catch-Up Artist

mark99 Re:Catch-up because (406 comments)

He does know how to swear like Gates (at least like he used to). And he does have a newish vision.

Kind of light on Enterprise though. MSFT needs someone who can do both. It is a tall order.

1 year,22 days
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SpaceX Launch Not So Perfect After All

mark99 Re:Transparency ? (272 comments)

I don't care how they dress. I thought the "Mohawk guy" on the Curiosity landing was pretty cool. So do most others I believe.

about 2 years ago
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Astronomy Portfolio Review Recommends Defunding US's Biggest Telescope

mark99 Defund the SLS instead (192 comments)

They should defund the Senate Launch System instead and fund more of these science programs. (Like a few more Mars Rovers).

about 2 years ago
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Fusion Power Breakthrough Near At Sandia Labs?

mark99 I believe (358 comments)

because I am an idiot and a slow learner.

about 2 years ago
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Ask Slashdot: Ambitious Yet Ethical Software Jobs?

mark99 Re:Ethical Dilemma (559 comments)

Nice. Seems a bit like rationalzation, yet the logic is undisputably there. Glad you had a good ride.

more than 2 years ago
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Ask Slashdot: Ambitious Yet Ethical Software Jobs?

mark99 Hobbiest Niche (559 comments)

Hope you don't want to have kids.

more than 2 years ago
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NASA, Congress Reach Accord On Commercial Crew Program

mark99 Re:Just as obvious.... ATK (137 comments)

Actually that last sentence doesn't parse. Are you saying that if ATK gets cut they wil somehow cause the selection process to be jettisoned? That sounds wrong...

more than 2 years ago
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NASA, Congress Reach Accord On Commercial Crew Program

mark99 Re:Just as obvious.... ATK (137 comments)

It sounds like you know what you are talking about, ... so you are depressing me.

Although I am pretty sure SpaceX will build a human rated Dragon regardless of what the CCD program decides.

more than 2 years ago
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NASA, Congress Reach Accord On Commercial Crew Program

mark99 Re:3 out of 4 (137 comments)

I think the Space Shuttle was just a big flop that only escaped being cancelled because the US Government has such deep pockets. In the end, in fact way before the end, it was a jobs program more than anything else. It set the space program back something like 20-30 years.
I don't understand why people can't just admit it was a horrible mistake. Actually, of course I do understand, so many valuable lifetimes of work were sunk into it.We have to pretend.... But we should have just been building cheaper rockets (which the two other programs on the table proposed) - or funding a Ramjet, or Roton, or almost anything else. The only really useful thing the Shuttle did was repair Hubble.

Imagine where we would be now if NASA had done something like COTS 20 years ago after Challenger blew up instead of building another Shuttle.

more than 2 years ago
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NASA, Congress Reach Accord On Commercial Crew Program

mark99 Re:Terms and conditions (137 comments)

I think NASA showed that they hadn't a clue what they should do with their terribly expensively developed "National Assets". They are all now rusting hulks. And they are developing another one with no clue as to what it is for (jobs for retiring engineers maybe).
At least the commercial guys are likely to rack their brains out as to how they can get more money out of "their" assets.
And face it - if a war broke out and SpaceX had useful assets, who do you think would control them overnight?

more than 2 years ago
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NASA, Congress Reach Accord On Commercial Crew Program

mark99 Re:Just as obvious.... ATK (137 comments)

Are you sure they have a chance? The article clearly states that they are to be selected form the *current 4*...

more than 2 years ago
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NASA, Congress Reach Accord On Commercial Crew Program

mark99 Re:3 out of 4 (137 comments)

What is your logic here? You think it costs signifcantly less to turn Dream Chaser around than a Dragon Capsule? It looks an awful lot like a Space Shuttle to me for that.
The two who seem to be doing a lot for bringing the price down would be Blue Origin (who are banking on a seemingly unlikely SSTO), and SpaceX with their Resuable Powered Decent stages (which also seem pretty far away at this point). It takes a 130 million Atlas V to put a Dream Chaser into orbit last time I looked, where as the Dragon only needs a 60 million dollar Falcon 9. Although Dream Chaser *could* probably fit on a Falcon 9 and in either case you are looking at additional costs on top of the basic launcher.

more than 2 years ago
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NASA, Congress Reach Accord On Commercial Crew Program

mark99 Re:Just as obvious.... ATK (137 comments)

Hard to beleive SpaceX would not be one of them at this point. In fact I think it is fair to say that Musk would drive the man rating of Dragon forward regardless of whether or not they get it, and that could potentially make the CCP program completely idiotic - i.e. if they went for something else and it cratered budget-wise, as space programs traditionally do.
Still, I am not convinced that a good deal of SpaceX's success is somehow begininers luck that could fade as the org grows and they take on too many goals (Man-rating Dragon, Falcon Heavy, Grasshopper, Bigelow, 10 Falcon launches a year, etc). Can they possibly do *all* of that?

more than 2 years ago
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NASA, Congress Reach Accord On Commercial Crew Program

mark99 Re:Just as obvious.... ATK (137 comments)

You think ATK can out manuver Boeing? Boeing is 10 times bigger.

more than 2 years ago
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Intelsat Signs Launch Contract With SpaceX

mark99 Every Part Tested? (167 comments)

Really? What about the center core propellent cross-feed? That sounds like a major piece that cannot have been launch tested yet. AFAIK there is no other rocket that has ever had it either so there must be some element of risk. All that mass transfer could go wrong in any number of ways I suppose.

more than 2 years ago
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Kenya Seeks Nuclear Power Infrastructure

mark99 Re:Go Solar (180 comments)

Solar is getting cheaper by about 10 percent a year, and has been for decades. And there is no reason to think it will be any different in the future. This cannot be said of any other form of energy.
And it has reached grid parity already in many places where incremental costs of additional capacity are high (like India).
Btw, I find your ignorance AND your rudeness appalling.

more than 2 years ago

Submissions

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mark99 mark99 writes  |  more than 7 years ago

mark99 (459508) writes "We all know that Biofuels have lots of problems, yet they seem to be the best bet for converting our economy to renewable enery without massive technical changes to our infrastructure. This article seems to disaggree, but it also seems full of logical fallicies, like implying that if there is no "net new crops", then there will be no carbon gain.

However conversion of biomass that would not have been eaten, but will be disposed of and turned into CO2 anyway reducing the amount of oil we dig out of the ground and vaporize would surely be a huge gain would it not? Or does this senario rely on tech that we do not have?

And it seems to imply that you have to put non-renewable energy in to get biomass generated energy out, that can't be right, since then it would never be profitable, but we know that it is once oil hits a certin cost. Is this worth discussing again, or have we beat this horse to death already?"

Journals

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mark99 mark99 writes  |  more than 10 years ago

Apparently you have to write a message to CowboyNiel. Says so at the bottom of the screen where you select all the topics that are displayed on your homepage.

Preferences tab and then Homepage Tab.

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mark99 mark99 writes  |  more than 10 years ago

Hello? I turned off daily messages to my gmx account in the Message Tab.

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mark99 mark99 writes  |  more than 10 years ago Hey, this isn't bad. Now I can make notes about how to use this monstrocity.

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