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Journal Journal: Geothermal vs Solar Power 1

Here are the basic numbers on aailable geothermal vs solar power (since this has come up in discussion more than once).

The surface area of the Earth is about 5.1 x 10^14 m^2. The cross sectional area is about 1.3 x 10^14 m^2 (one quarter of the surface area, of course).

Per this paper found as a cite on wikipedia, the total heat flow out from the Earth's interior is 4.42 x 10^13 W, or 0.0867 W/m^2. Of course, the available power is much less because it's only the subsurface-surface temperature difference that's available.

Total solar irradience is 1361 W/m^2 by NASA's latest estimate (so about 1.7 x 10^17 W across the entire cross section), or about 1000 W/m^2 on the surface at noon on a cloudless day. Averaged over the day-night cycle (surface area vs cross-section, so 250 W/m^2), and taking clouds into account that's about 180 W/m^2 (I can't find a solid source on that yet, but it looks close).

So, total solar power flow is about 4000 times as large as total geothermal flow. I'm not quite sure how to estimate the (ideal) available power as a percentage of the total geothermal power flow, but if we use a WAG of 50%, then the available power from solar is also about 4000 times per square meter more than geothermal - significantly more if we average solar power only across populated latitudes.

Math

Journal Journal: help with math 1

Hopefully somehow out there is better with math than I.

Suppose a giant ball of ice, 130km in diameter (water volume significantly greater than the Great Lakes) were to strike the moon at a speed of 3km/s (just above the moon's escape velocity). If my math is right, most of the water will remain on the moon in the newly formed crater, though I'm sure a significant amount would sublimate away over time.

Any help would be appreciated.

Oh, and this is for a possible scifi story. I just want to make sure the basis for the drama is at least plausible, it doesn't have to be 100% exact.
The question, how much water would end up left behind? I'm not sure if it would rival Lake Superior, Lake Erie, some other lake, or essentially none at all.

User Journal

Journal Journal: Tags? 3

Am I the only one who can't see tags on stores in the new Slashdot 3.0? No matter which story I'm looking at, there are no tags showing up. Which is too bad, because there's usually a lot of meta-humor contained in those things.

If anyone else had this problem and fixed it, please let me know what to do. I'm using the latest Firefox on WinXP SP2.

User Journal

Journal Journal: Games vs sports 2

I feel that the perennial debate over the difference between games and sports is viewed very, very wrongly by our society. Games are viewed as being childish fripperies, whereas sports are serious tasks that require tactics and dedication. This is utter balderdash. Here is how I would define the difference between a sport and a game:

The activity in question shall be known as X.

if (X.winner(fitMan, skilledMan) == fitMan) {
xIsASport = true;}
else{
xIsASport = false;}

In other words, if a skilled but unfit man can be beaten by an unskilled but very fit man, it is a sport. Examples would be long distance running, football / soccer, or weightlifting. If the converse is true, then the activity is a game. Examples include chess, Call Of Duty MP, WoW PvP, darts, snooker... the list goes on.

I think it is clear from this brief series of examples that games are by far the superior pastime, and yet sports are given a huge amount more time, money, and respect.

Of course, this is somewhat a strawman argument - I am defining common words to mean what I want them to mean so that my argument holds. However, I do feel that this is the most sensible way to delineate the two concepts of game and sport - to establish a continuum with no clear or strict boundary, but which most activities will clearly settle on one side or the other of.

Now that that's off my chest, I'm off to play a game. Or maybe a sport. We shall see...

User Journal

Journal Journal: Long time, no see 1

It has been a bit more then a month since I have last seen Slashdot. I have discovered the greatness of Facebook, and have become adicted to it. I am scared

User Journal

Journal Journal: Controlling my computer with a phone

I am, at this very moment, using my tmobile mytouch slide to control my laptop. I don't know how this technology works, but it is awsome! I can, literally, control my computer from anywhere.

User Journal

Journal Journal: New Phone, New "Mom", Lifes Good

Two great pieces of news. One is that I have achieved something some geeks don't, I moved out of my moms house, but into my grandmas house. My grandma obtained official legal custody today. I'm happy. I am away from my mom the bitch.
The other good news is I got a new android phone, the tmobile mytouch swipe. Love at first use on this phone. Review comming later.

User Journal

Journal Journal: School Interesting

I write an essay yesterday, making it sound as downplaying to the average person, and I get 20 out of 20. Something is wrong with that. I tell a person that they have no way of join the geek society if they don't join before age 10 and yet she gives me 20 out of 20. Jeez. I mean, it was meant to see how biased her grading scale is, in terms of insults. I gave her the ultimate insult and called the people reading, for a lack of better terminology at the time, STUPID! I sometimes wonder. Does this indicate that the average person is willing to admit that nerds and geeks are better than them? Or is it that she didn't have the ability to find another different English teacher for me for the rest of the year? She is a seemingly average American. Something is wrong with America, if a teacher tells a student good job for calling her stupid. Other than the fact that they force children to go to school.

Firefox

Journal Journal: Just noticed something

Every time I decide to mess off on my school computer in school, I observe the following things. 1. I end up in Firefox Private Browsing. 2. I end up with a full bar (or more) of minnimum-sized tabs. 3. My beautiful girls flash drive becons to me.
Is this normal?

Firefox

Journal Journal: Wow

I just got on a computer, loaded up runescape, used the KVM to hide that i was on Facebook and Slashdot, and found the computer that i didn't re-install had firefox 2.something, 2.5 i think. I am amazed. I mean, i haven't used anything before 3.5 at all this year, and i find firefox 2.5 on a computer

User Journal

Journal Journal: Slashdot in Negative 1

Just a disclaimer: I am using a POS iBook G4. This method is not guaranteed to work for any other computer.
Anyway, Slashdot looks so cool in negative. I got to it by pressing Command, Option, Ctrl, and 8, all at the same time. But it looks cool, especially the apple page.

User Journal

Journal Journal: Some assholes

Today, i find out that some asshole stole the remainder of my fresh gum supply, four pieces. So now, until i can get to the store, i have to survive on pre-chewed gum. At least it is myself who prechewed it.

User Journal

Journal Journal: New hosts.txt file 2

I am currently trying to make a new hosts file as defined in numerous standards, and want a list of websites to spawn it on. Can someone give me a list?

User Journal

Journal Journal: Curious of the old internet

Does anyone have an old copy of the SRI-NIC Hosts.txt file? I want a copy of such so that I can do a study on the history of the internet, along with create a list of web sites in current use.

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