5 ms·

tl;dr - The Apollo 11 computer ran at 0.001GHz with 0.000002GB memory and 0.000032GB of storage (read-only at that). The display amounted to a few dozen 1-bit p

tl;dr - The Apollo 11 computer ran at 0.001GHz with 0.000002GB memory and 0.000032GB of storage (read-only at that). The display amounted to a few dozen 1-bit pixels. And it took them to the Moon.

sp332 13y ago
Now we seem to be completely dependent on computers, but at the time, I'm sure they didn't rely on them as much. The people pretty much navigated themselves to the moon
- CapitalistCartr 13y ago
  At a speaking engagement by James Lovell, I heard him describe the emergency procedure for navigating that they did with Apollo 13. There was a large round port window facing forward with a line engraved across the middle. Line that up with Earth's terminator line like cross hairs. Fire the main engine by hand. That's it. And it worked.
- R_Edward 13y ago
  Some time ago, I was trying to buy a few hundred dollars worth of furniture, only to be informed that the cashier could not process my order because her computer was down. Everything I was buying had a price tag and I was paying cash, so I suggested that she find a pencil and some paper, and just write everything down, so she could enter it when the computer came back online. The concept apparently fried a circuit or two in her brain, because there was 6% sales tax on everything, and how was she supposed to know how much that would be? Plus, how was she supposed to know how much change to give me? Nowadays, we don't have price tags on anything anymore. Prices are fetched from a database using the UPC as a key, so if the computer's down, the buyer is out of luck. At a previous employer, we sold specialty goods to contractors, so we had strong relationships with our customers. I drafted a plan to print up pads of paper sale forms that looked more or less like our (80x24 greenscreen) order screens, so if we lost connection to the mainframe, we could still move product from the warehouse to the customers; we'd just give them the product and bill 'em later. It was a risky move, but not really any riskier than sending our customers across the street to our competitors. To my knowledge, they've never had to use the manual system, thankfully. We may not be "completely dependent on computers" just yet, but we seem to be getting there.
  - laxatives 13y ago
    I know you're making a point, but it just sounds like you were dealing with particularly incompetent cashiers. I've been to a number of brick and mortar stores where they had a system exactly as you described. They simply copied my credit card onto carbon paper and wrote in the calculated total so that they could take care of the billing when the system came back online.
    - R_Edward 13y ago
      I don't dispute the claim that there are very competent cashiers all over the place. I just seem to be particularly lucky in finding their counterparts whose greatest usefulness is in flattening the curve. Also, isn't it a little risky letting someone copy your credit card like that? Even if you trust the cashier not to steal the number, how do you know whether they're destroying the information after they're done with it?
      - showerst 13y ago
        Those carbon copiers were the way they charged CCs for years before computers, right? So presumably there are a decent number of safeguards built in. (Disclaimer: I'm 29, so don't really remember a time when those things were commonly used.)
        R_Edward 13y ago
        Well, yes, that's the way they did it before computers, but no, the safeguards really weren't there. They used carbon paper to transfer the number from the card to the leaves of the receipt. So when the carbon gets discarded, it becomes trivial for someone downstream of the transaction to pull the carbon out of the trash and use the embedded number to do some internet or telephone-based shopping of his own. It's funny--29 doesn't sound particularly young, but I'm really suppressing the urge to call you a whippersnapper.
      - sdkmvx 13y ago
        Before widespread communications networks, credit card imprints were taken with machines that look like [1]. They are still sometimes used when networks are down or when there is no phone/Internet network (think temporary locations like fairs and carnivals). The security is that the credit card company will (hopefully) void invalid transactions... [1] http://img.ehowcdn.com/article-new/ehow/images/a04/b9/g6/credit-card-imprinter-work-800x800.jpg http://img.ehowcdn.com/article-new/ehow/images/a04/b9/g6/cre...
- kalleboo 13y ago
  I thought it was mostly rocket science? (calculating trajectories in advance, on supercomputers on the ground)
  - RBerenguel 13y ago
    Super...what? Actually, I asked my teacher on celestial dynamics how to determine a good trajectory to get "somewhere." The answer? "Clicking." So you just keep trying different solutions until you find it, or something close enough and then numerically optimise the solution.
- smackfu 13y ago
  Well, the other real alternative was to determine their position, etc., then send that data back to NASA who would use their big computers to do the calculations, then send back the burn duration, etc.
  - lostlogin 13y ago
    Ahh, the cloud option.
- rst 13y ago
  Actually, the lunar descents were all on autopilot until fairly close to the surface. And even when the astronauts took "manual" control, the LEM was still fly-by-wire, like a lot of modern aircraft: the guidance computer was reading the movements of the joysticks and translating that into thruster settings. (Pulling the joysticks "hard over" would bypass the computers, but that was considered an emergency measure only.) The LEM software was supposed to be capable of a fully automatic landing, but none of the astronauts rode it all the way down. David Mindell's book "Digital Apollo" goes into these systems, and their development, in much detail; the discussion of the LEM user interface is in chapter 8.
kalmi10 13y ago
I love reading this: http://www.hq.nasa.gov/alsj/a11/a11.landing.html http://www.hq.nasa.gov/alsj/a11/a11.landing.html "This display does not place a particularly heavy load on the computer, but when added to the existing load, was sufficient to generate the 1202 alarm." --- "102:38:26 Armstrong: (With the slightest touch of urgency) Program Alarm. 102:38:28 Duke: It's looking good to us. Over. 102:38:30 Armstrong: (To Houston) It's a 1202. 102:38:32 Aldrin: 1202. (Pause)" http://www.dailykos.com/story/2012/08/25/1124164/-Neil-Armstrong-the-1201-alarm-and-what-it-means-to-be-great http://www.dailykos.com/story/2012/08/25/1124164/-Neil-Armst... --- "102:36:18 Armstrong: (To Houston) Our position checks down range show us to be a little long. 102:36:21 Duke: Roger. Copy. (Heavy Static) [In a post-mission analysis, Apollo Descent and Ascent Trajectories, Floyd Bennett notes that, at PDI, Eagle was about 3 miles farther downrange than planned, due to [..]" -> ... after that, Armstrong selected a landing site visually, and landed the lunar module manually. :) [Mission Control] Thirty seconds. (Just Mission Control telling Neil Armstrong how many seconds of fuel he has left for landing) :)
- minikites 13y ago
  If you like this, there's Spacelog, which is a neat way to view transcripts for a number of missions: http://apollo11.spacelog.org/ http://apollo11.spacelog.org/ http://apollo13.spacelog.org/ http://apollo13.spacelog.org/ Browsing through the Apollo 13 "spacelog", it's interesting how a lot of the lines in the Apollo 13 movie are very similar to the ones in real life.
sigkill 13y ago
It's pretty awesome to know that you can get something that powerful inside your palm (the Atmega 328) for less than $3 single unit prices. After some minor conversion, the Atmega/Arduino has almost exactly same storage space and RAM. Only, the Arduino clocks at 16MHz. Still, awesome regardless.
- solistice 13y ago
  That was the Block II version though. The previous version (at 24k Storage and 1k memory) is proably closer to the ATtiny1634, which only has 16k of main storage but clocks at a veritable 20Mhz. The thing I find amazing is that there's a bga version of that chip that is 2x2mm. And they're like <2$ single unit. Sorry for whipping out my 1634 pet peeve.

tl;dr - The Apollo 11 computer ran at 0.001GHz with 0.000002GB memory and 0.000032GB of storage (read-only at that). The display amounted to a few dozen 1-bit pixels. And it took them to the Moon.

sp332 13y ago

Now we seem to be completely dependent on computers, but at the time, I'm sure they didn't rely on them as much. The people pretty much navigated themselves to the moon

CapitalistCartr 13y ago
At a speaking engagement by James Lovell, I heard him describe the emergency procedure for navigating that they did with Apollo 13. There was a large round port window facing forward with a line engraved across the middle. Line that up with Earth's terminator line like cross hairs. Fire the main engine by hand. That's it. And it worked.
R_Edward 13y ago
Some time ago, I was trying to buy a few hundred dollars worth of furniture, only to be informed that the cashier could not process my order because her computer was down. Everything I was buying had a price tag and I was paying cash, so I suggested that she find a pencil and some paper, and just write everything down, so she could enter it when the computer came back online. The concept apparently fried a circuit or two in her brain, because there was 6% sales tax on everything, and how was she supposed to know how much that would be? Plus, how was she supposed to know how much change to give me? Nowadays, we don't have price tags on anything anymore. Prices are fetched from a database using the UPC as a key, so if the computer's down, the buyer is out of luck. At a previous employer, we sold specialty goods to contractors, so we had strong relationships with our customers. I drafted a plan to print up pads of paper sale forms that looked more or less like our (80x24 greenscreen) order screens, so if we lost connection to the mainframe, we could still move product from the warehouse to the customers; we'd just give them the product and bill 'em later. It was a risky move, but not really any riskier than sending our customers across the street to our competitors. To my knowledge, they've never had to use the manual system, thankfully. We may not be "completely dependent on computers" just yet, but we seem to be getting there.
- laxatives 13y ago
  I know you're making a point, but it just sounds like you were dealing with particularly incompetent cashiers. I've been to a number of brick and mortar stores where they had a system exactly as you described. They simply copied my credit card onto carbon paper and wrote in the calculated total so that they could take care of the billing when the system came back online.
  - R_Edward 13y ago
    I don't dispute the claim that there are very competent cashiers all over the place. I just seem to be particularly lucky in finding their counterparts whose greatest usefulness is in flattening the curve. Also, isn't it a little risky letting someone copy your credit card like that? Even if you trust the cashier not to steal the number, how do you know whether they're destroying the information after they're done with it?
    - showerst 13y ago
      Those carbon copiers were the way they charged CCs for years before computers, right? So presumably there are a decent number of safeguards built in. (Disclaimer: I'm 29, so don't really remember a time when those things were commonly used.)
      - R_Edward 13y ago
        Well, yes, that's the way they did it before computers, but no, the safeguards really weren't there. They used carbon paper to transfer the number from the card to the leaves of the receipt. So when the carbon gets discarded, it becomes trivial for someone downstream of the transaction to pull the carbon out of the trash and use the embedded number to do some internet or telephone-based shopping of his own. It's funny--29 doesn't sound particularly young, but I'm really suppressing the urge to call you a whippersnapper.
    - sdkmvx 13y ago
      Before widespread communications networks, credit card imprints were taken with machines that look like [1]. They are still sometimes used when networks are down or when there is no phone/Internet network (think temporary locations like fairs and carnivals). The security is that the credit card company will (hopefully) void invalid transactions... [1] http://img.ehowcdn.com/article-new/ehow/images/a04/b9/g6/credit-card-imprinter-work-800x800.jpg http://img.ehowcdn.com/article-new/ehow/images/a04/b9/g6/cre...
kalleboo 13y ago
I thought it was mostly rocket science? (calculating trajectories in advance, on supercomputers on the ground)
- RBerenguel 13y ago
  Super...what? Actually, I asked my teacher on celestial dynamics how to determine a good trajectory to get "somewhere." The answer? "Clicking." So you just keep trying different solutions until you find it, or something close enough and then numerically optimise the solution.
smackfu 13y ago
Well, the other real alternative was to determine their position, etc., then send that data back to NASA who would use their big computers to do the calculations, then send back the burn duration, etc.
- lostlogin 13y ago
  Ahh, the cloud option.
rst 13y ago
Actually, the lunar descents were all on autopilot until fairly close to the surface. And even when the astronauts took "manual" control, the LEM was still fly-by-wire, like a lot of modern aircraft: the guidance computer was reading the movements of the joysticks and translating that into thruster settings. (Pulling the joysticks "hard over" would bypass the computers, but that was considered an emergency measure only.) The LEM software was supposed to be capable of a fully automatic landing, but none of the astronauts rode it all the way down. David Mindell's book "Digital Apollo" goes into these systems, and their development, in much detail; the discussion of the LEM user interface is in chapter 8.

kalmi10 13y ago

I love reading this: http://www.hq.nasa.gov/alsj/a11/a11.landing.html http://www.hq.nasa.gov/alsj/a11/a11.landing.html "This display does not place a particularly heavy load on the computer, but when added to the existing load, was sufficient to generate the 1202 alarm." --- "102:38:26 Armstrong: (With the slightest touch of urgency) Program Alarm. 102:38:28 Duke: It's looking good to us. Over. 102:38:30 Armstrong: (To Houston) It's a 1202. 102:38:32 Aldrin: 1202. (Pause)" http://www.dailykos.com/story/2012/08/25/1124164/-Neil-Armstrong-the-1201-alarm-and-what-it-means-to-be-great http://www.dailykos.com/story/2012/08/25/1124164/-Neil-Armst... --- "102:36:18 Armstrong: (To Houston) Our position checks down range show us to be a little long. 102:36:21 Duke: Roger. Copy. (Heavy Static) [In a post-mission analysis, Apollo Descent and Ascent Trajectories, Floyd Bennett notes that, at PDI, Eagle was about 3 miles farther downrange than planned, due to [..]" -> ... after that, Armstrong selected a landing site visually, and landed the lunar module manually. :) [Mission Control] Thirty seconds. (Just Mission Control telling Neil Armstrong how many seconds of fuel he has left for landing) :)

minikites 13y ago
If you like this, there's Spacelog, which is a neat way to view transcripts for a number of missions: http://apollo11.spacelog.org/ http://apollo11.spacelog.org/ http://apollo13.spacelog.org/ http://apollo13.spacelog.org/ Browsing through the Apollo 13 "spacelog", it's interesting how a lot of the lines in the Apollo 13 movie are very similar to the ones in real life.

sigkill 13y ago

It's pretty awesome to know that you can get something that powerful inside your palm (the Atmega 328) for less than $3 single unit prices. After some minor conversion, the Atmega/Arduino has almost exactly same storage space and RAM. Only, the Arduino clocks at 16MHz. Still, awesome regardless.

solistice 13y ago
That was the Block II version though. The previous version (at 24k Storage and 1k memory) is proably closer to the ATtiny1634, which only has 16k of main storage but clocks at a veritable 20Mhz. The thing I find amazing is that there's a bga version of that chip that is 2x2mm. And they're like <2$ single unit. Sorry for whipping out my 1634 pet peeve.