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## Comment Re:economic case with different assumptions... (Score 2)163

Actually, I do know these things, but didn't bother to include all the sources, given it being Christmas and all. Since you are so insistent about it though...

Points 1 & 3 are taken from direct quotes by Elon Musk
Point 2 is taken from the design of the Falcon 9, available at spacex or nearby wikipedia.
"re-use without refurbishment" another direct E. Musk quote.

Spacex current launch rate (6 per year) and cadence and published launch costs and satellite weights for commercial space companies are just a google search away. Try this excellent site: http://www.spacelaunchreport.c... for starters

A very informative and useful place to find much of this information and discussion by knowledgeable space experts and enthusiasts is at: http://www.nasaspaceflight.com...

The rest is just simple math.

To sum up, I do have details, I'm not guessing, and I note where I make assumptions. Find fault with my assumptions if you like, but please explain why those assumptions are flawed with specifics, not generalities.

## Comment Re:economic case with different assumptions... (Score 4, Insightful)163

Interesting numbers. Let's try a variant case. Suppose in addition: You're assuming that the non-reusable launch vehicle cost per launch is \$60M. OK, let's start out by assuming 1/3 of that is fixed costs and operations costs, and 2/3 the vehicle cost, which is split evenly between the two stages (first stage is larger, but not proportionately more expensive). So, of the \$60 million, \$40 million is spent even if the vehicle first stage was free. Now assume that re-usability increases the launch cost by, say, \$5 million (launch operations are expensive! and the cost is not entirely the vehicle). Assume that all the stuff needed to make the first stage reusable increases the stage cost by 25%, from \$20M to \$25M. And assume that the delta-V and the added mass to do the fly-back decreases payload by 10%, and that the price you sell the launch for decreases a similar percentage (some payloads won't care, but some will.)

First off, the current cost of the rocket already includes the costs to do reusibilty, so the cost of the first stage will not increase- it is designed be reused up to 10 times right now with no change in hardware.

Secondly, the cost of the 2 stages are not even remotely close to equal; the first stage has 9 Merlin engines, the second stage only has 1. An estimate of 6 to 1 (first to second) for costs would be more reasonable.

Thirdly, the payloads currently quoted already include reusability (16MT to LEO and 4.5MT to GTO). No loss of earnings there.

So none your variant assumptions are useful for this discussion.

Let's look at some other factors you haven't considered.

Like the space shuttle, SpaceX now has a rocket for examination that has flown a full mission and hasn't had a 6G salt water landing. This means that they will be able to do full engineering analysis on what stresses the rocket actually experienced during a flight event that increase all steps necessary for re-use. The results of that analysis will allow them to determine what parts of the rocket need to be enhanced or reduced to meet the 10 tens re-use goal. SpaceX has the luxury of being to make changes to their rocket without Congressional approval, so this information can be used immediately to improve the vehicle. The design goal of the Falcon is that the rocket need not be "refurbished" after every flight, just put through some standard flight maintenance tests. Having the flown stages available for analysis will help them to meet this goal.

Additionally, SpaceX currently has launch costs based on 6 launches a year. As they have already demonstrated the ability to launch with a cadence of 2 weeks several times, being able to increase their launch rate to a minimum of 1 a month will cut their overall costs per launch.

Let's assume that a slight redesign based on analysis of real-world data let's them increase reliability of the Falcon 9 to 1 in 100 and increase the payload by 1MT to GTO. At 5.5MT to GTO, this let's them handle 90% of all GTO launches (6MT is at the current top end for commercial satellites to GeoSynchronous orbits) with the reuable design. 5MT is compable to \$137M Ariane 5 capbility or \$132M for an Atlas 5 launch for NASA with both the throw weight and reliability requirements necessary to get these flights.

\$60M to launch the current, reusable Falcon 9 1.1FT.
33% is launch cost. - \$20M
56% is first stage - \$34M
11% is the second stage \$6M

Assumption 1: increase in flight rate reduces launch costs by 25%
Assumption 2: landing/recovery/flight readiness check costs \$5M a launch
Assumption 3: 10 flights reuse of the first stage = \$3.5M a launch

Under these assumptions:
Launch cost \$15M
Landing/recovery/checks \$5M
First stage \$3.5M
Second Stage: \$6M

Total: \$29.5M

I'm OK with those numbers given what they can charge and how quickly they can do regular launches. Where they will really rake in the cash is for a Facon Heavy launch (same vehicle with 3 first stages instead of 1) with 56MT to LEO for an asking price of \$110M and a cost, by these assumptions of \$35M. They could even reduce their price after a few launches of the Heavy to \$56M, and start launching bulk cargo to space at a rate of \$1000/Kg

## Comment WSJ is incorrect in title, implication (Score 4, Informative)434

From Daily Kos:

"Late Thursday night, the Times published a story claiming that the Justice Department had been asked "to open a criminal investigation into whether Hillary Rodham Clinton mishandled sensitive government information on a private email account," only to quietly change the story to say that the Justice Department had been asked "to open a criminal investigation into whether sensitive government information was mishandled in connection with the personal email account Hillary Rodham Clinton used." As in, the story changed from being about a potential criminal investigation into Clinton's conduct to being about a potential criminal investigation into the mishandling of sensitive information by ... someone not named. "

So, haven't you guys learned yet to ignore mass media reporting when it involves a Clinton? It's almost like someone with billions of dollars has been trying to smear the leading Democratic candidate for a few years now.

## Comment New scheme (Score 1)199

Obviously, the next verision of Linux needs to be "Linux 11 for Computers" - we need to look more advanced than OS X and Windows 10.

Other variants can be "Linux 2015 Mobile Edition" for phones and tablets, and "Linux Server 2011 (Based on Linux 3.0 technology)" for servers.

## Comment No. (Score 1)239

Any headline that ends in a question mark can be answered with "No."

Mass surveillance won't end. We have a new era of existence now, and that era includes easy access to anything you've ever communicated.

The thing we'll need to keep in check is how the information collected is used, which is part of the reason why personal right and acceptance of others is so important.

## Comment "Open source made easy" (Score 1)598

The back of the 10.4 server box said "Open source made easy" - and that's what it was, a lot of open technologies pulled together and given focus by Apple. Samba, bind, Apache, MySQL, openldap, etc all controlled with a pretty decent gui. Even the Mach kernal had an open version you could download and use with a bad-like user land (darwin).

Then in 10.5 they started removing the open parts and closing it all up. 10.4 could be a windows domain controller thanks to leveraging samba- today's OS X server can't, because Apple decided to replace samba with a closed implementation.

Not only has Apple made more work for themselves, they are actively pushing away the users that help grow the platform. Sure, the grandparents don't care if there's a decent xserver included- but the young person who helps keep their computers working (and tells them what to buy) does.

I embraced OS X when 10.4 for intel came out, because I could run anything. I could compile my Unix tools and use them on a nice, more focused platform. Now that's much more difficult, and instead of looking forward to what's next from Apple, I'm wondering how much longer I can stand to stay in the ecosystem.

## Comment Finally a moden display for my arcade cabinet (Score 1)330

I've been looking for a square (or 4:3) ~27 inch display forever, for an arcade cabinet build. There are CRT SDTVs out there but they are horrible and getting rare. This may do the trick.

## Comment Wow (Score 1)27

This is straight out of science fiction.

I can see it now, a comic book super villain and his swarm of programmable insects.

What a time to be alive.

## Comment I for one, (Score 5, Insightful)108

Thank our KDE developers for their hard work. I'm really impressed by KDE and have used it a lot over the years.

## Comment Re:Simple innovations are the best. (Score 1)253

There was a study a while back that showed that most NASCAR drivers and crews had lead poisoning due to the leaded fuel- they didn't move to unleaded fuel until 2008!

So in a way, we've already seen NASCAR with drivers under the influence.

## Submission + - Why Standard Deviation Should Be Retired From Scientific Use (edge.org) 1

An anonymous reader writes: Statistician and author Nassim Taleb has a suggestion for scientific researchers: stop trying to use standard deviations in your work. He says it's misunderstood more often than not and also not the best tool for its purpose. 'It is all due to a historical accident: in 1893, the great Karl Pearson introduced the term "standard deviation" for what had been known as "root mean square error." The confusion started then: people thought it meant mean deviation. The idea stuck: every time a newspaper has attempted to clarify the concept of market "volatility", it defined it verbally as mean deviation yet produced the numerical measure of the (higher) standard deviation. But it is not just journalists who fall for the mistake: I recall seeing official documents from the department of commerce and the Federal Reserve partaking of the conflation, even regulators in statements on market volatility. What is worse, Goldstein and I found that a high number of data scientists (many with PhDs) also get confused in real life.'

## Submission + - To OLPC or not to OLPC (laptop.org)

koubalitis writes: A friend of mine, an elementary school principaly in Greece, has asked me to help him evaluate the following situation, An ex student of the elementary school, now in his 70', wants to make a donation in the form of computer laptops. He is willing to buy a laptop for every student in the school, arround 150. He suggested getting OLPCs which cost arround 250-280euros per piece (including shipping and import taxes) but he is open to other alternatives. The principal gave me a sample OLPC XO-4 unit for evaluation. The truth is i wasn't impressed. It doesn't have support for Greek (UI or keyboard layout), the screen is too small, it feels too slow and the whole environment is too restrictive. On the other hand i liked the ruggedized plastics and the battery life. 300euros can get you a descent 11'' dual core netbook with linux preinstalled . So the question is this. Should we go for the OLPC or an alternative netbook/laptop/tablet? Does any slashdoter have experience with OLPCs?

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