The HST does not have sufficient resolution for this. The biggest thing that astronauts left on the moon is on the order of 1m, and the moon is 4e8 meters away, for an angular size of about 2.5e-9 radians. To resolve this at a wavelength of 800nm, you need a circular mirror with a diameter of 390m = 1.22 * 8e-7 / 2.5e-9. It would be cheaper to go and look, rather than to build a mirror that big.
A circle that has an area of 60km^2 has a radius of 4.5km. The distance from a station on the perimeter of this little circle to the balloon is 24.5km = sqrt( 4.5^2 + 24^2 ), by Pythagoras. Nobody would ever deploy a transmitter that could reach 24km, but not 500m further.
The angle subtended by a station on the perimiter of the little circle and a second station on the perimiter diametrically opposed to the first is 20 degrees = 2 * arctan( 4.5/24 ). Nobody would ever deploy an antenna with a 20 degree beamwidth for this application.
If the circle has a radius of 60km, then the station on the perimeter is 64km away from the baloon (less than 10db down compared to a station directly underneath, 24km away), and the beamwidth would be about 135 degrees. Much more likely.
If the key has your room number and length of stay, then my lost & found room key plus a $39 magnetic stripe card reader equals a stolen laptop, right?
Just about every rocket is orbital for some portion of its journey (unless it turns into a glider immediately after its engines shut off). It's just that the orbit intersects the surface of the earth - no big deal, really.
If you do have free WiFi in a cafe, you have to tie it to purchases. An identifier on the reciept is good. Otherwise, I'll rent an apartment down the street, mount a cantenna on my balcony, and point it at your café.
The scheme to generate the identifier doesn't have to be all that clever. There's a few bits of entropy in the purchase price, after all.
10M email per day, $0.0001 per email cost to victims. That's only 1/100th of a penny, surely a lower bound.
10,000,000 * $0.0001 = $1000 per day. Let's say he's a little lazier than the average Joe, so he only works 200 days per year. That's still $200K per year to have him on the outside.
md5sum only outputs charactes in the set [0-9a-f], for 16 possibilities. Suppose you use those characters for your passwords, and I use the 64 characters [A-Za-z0-9.!] for mine. My passwords, of the same length, are lg( 64 ) / lg( 16 ) = 1.5 times as effective as yours. This means that your 6 character password is only as good as my 4 letter password.
I doubt if this is something that humans can detect with their eyes, since our brains automatically apply drastic correction factors for ambient light. Although we all notice when a cloud blocks the sun, I know that during a partial solar eclipse. It's basically impossible to notice a gradual 20% dimming of the ambient sunlight. (At least I can't tell, and there always seems to be masses of people who don't notice...)
In absolute terms, a snowball in your living room at night with the light on reflects about as much light as a lump of coal does in direct sunlight. You can tell the difference between direct sunlight and indoor lights, of course, but the correction is good enough to decode coal == black, snow == white.
Glass has a cutoff for transmittance of wavelengths longer than about 3000nm. The sun, at 6000 Kelvins, radiates a lot in the 700nm - 3000nm range, which is just infrared of visible. Your room, at about 300 Kelvins produces a lot less radiation, and most of it is in the far infrared (peak at around 8000nm) that glass doesn't transmit at all.
This coating probably reduces transmittance of the near infrared, and you just have to put up with the default behaviour of glass not transmitting the far infrared.
LEA was "Load Effective Address" for the 8086, and it was a fast (and obscure, sidey-affecty) way to speed up a certain set of multiplication (and combo multiplication/addition) operations, which I now forget. Where's Abrash when you need 'im?
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"Never underestimate the bandwidth of a station wagon full of tapes hurtling down the highway."
The HST does not have sufficient resolution for this. The biggest thing that astronauts left on the moon is on the order of 1m, and the moon is 4e8 meters away, for an angular size of about 2.5e-9 radians. To resolve this at a wavelength of 800nm, you need a circular mirror with a diameter of 390m = 1.22 * 8e-7 / 2.5e-9. It would be cheaper to go and look, rather than to build a mirror that big.
A circle that has an area of 60km^2 has a radius of 4.5km. The distance from a station on the perimeter of this little circle to the balloon is 24.5km = sqrt( 4.5^2 + 24^2 ), by Pythagoras. Nobody would ever deploy a transmitter that could reach 24km, but not 500m further.
The angle subtended by a station on the perimiter of the little circle and a second station on the perimiter diametrically opposed to the first is 20 degrees = 2 * arctan( 4.5/24 ). Nobody would ever deploy an antenna with a 20 degree beamwidth for this application.
If the circle has a radius of 60km, then the station on the perimeter is 64km away from the baloon (less than 10db down compared to a station directly underneath, 24km away), and the beamwidth would be about 135 degrees. Much more likely.
If the key has your room number and length of stay, then my lost & found room key plus a $39 magnetic stripe card reader equals a stolen laptop, right?
But you can make even more if you do, and publicly traded corporations are bound by law to make the best return possible for their shareholders.
Just about every rocket is orbital for some portion of its journey (unless it turns into a glider immediately after its engines shut off). It's just that the orbit intersects the surface of the earth - no big deal, really.
He's got soooooo many, they're going to let him stay in space until October. For free!
The scheme to generate the identifier doesn't have to be all that clever. There's a few bits of entropy in the purchase price, after all.
A Faraday cage? You mean like a tinfoil hat or something?
$50k per year to lock him up. Okay.
10M email per day, $0.0001 per email cost to victims. That's only 1/100th of a penny, surely a lower bound.
10,000,000 * $0.0001 = $1000 per day. Let's say he's a little lazier than the average Joe, so he only works 200 days per year. That's still $200K per year to have him on the outside.
md5sum only outputs charactes in the set [0-9a-f], for 16 possibilities. Suppose you use those characters for your passwords, and I use the 64 characters [A-Za-z0-9.!] for mine. My passwords, of the same length, are lg( 64 ) / lg( 16 ) = 1.5 times as effective as yours. This means that your 6 character password is only as good as my 4 letter password.
In absolute terms, a snowball in your living room at night with the light on reflects about as much light as a lump of coal does in direct sunlight. You can tell the difference between direct sunlight and indoor lights, of course, but the correction is good enough to decode coal == black, snow == white.
A wide ultra-extended graphics array is clearly the better alternative to a super ultra-extended graphics array.
Glass has a cutoff for transmittance of wavelengths longer than about 3000nm. The sun, at 6000 Kelvins, radiates a lot in the 700nm - 3000nm range, which is just infrared of visible. Your room, at about 300 Kelvins produces a lot less radiation, and most of it is in the far infrared (peak at around 8000nm) that glass doesn't transmit at all. This coating probably reduces transmittance of the near infrared, and you just have to put up with the default behaviour of glass not transmitting the far infrared.
LEA was "Load Effective Address" for the 8086, and it was a fast (and obscure, sidey-affecty) way to speed up a certain set of multiplication (and combo multiplication/addition) operations, which I now forget. Where's Abrash when you need 'im?