5,372 reputation
1631
bio website keith-s-thompson.github.com
location San Diego, CA
age 55
visits member for 3 years, 2 months
seen 2 days ago

I'm a programmer and all-around nerd living in San Diego, California.
I work at JetHead Development Inc.

E-mail: Keith.S.Thompson@gmail.com


Dec
21
revised Do the stars imaged by a telescope even exist at present?
Discuss Milky Way supernova frequency
Dec
19
awarded  Nice Answer
Dec
19
comment Can I survive a free fall using a ramp and a rope?
A little elasticity in the rope might be enough to fling the ramp ahead of you. Not that the while idea is particularly realistic.
Dec
19
comment Can I survive a free fall using a ramp and a rope?
The question states that the ramp is very light. The idea is that when you reach the end of the rope, the ramp is pulled up along with you without significantly slowing you down. It then lands on the ground ahead of you, ready to cushion your fall again. (The ramp, of course, is made of pure unobtainium.)
Dec
9
comment How might clock synchronization work with RSA SecurID tokens?
Sounds like you could mess up the server's idea of your token's clock drift by waiting a while before entering your code, or entering one you generated a few minutes ago. I don't think that's exploitable, though.
Dec
8
comment Is there a small enough planet or asteroid you can orbit by jumping?
Another approach: Take a rock with you, and throw it directly backwards when you're half way around. This should give you enough extra velocity so your orbit doesn't intersect the surface at your starting point.
Dec
8
comment Don't heavier objects actually fall faster because they exert their own gravity?
The classic experiment, as performed by Galileo and David Scott, involves dropping two objects simultaneously. In that case, the pull of the larger mass also affects the falling time of the smaller mass, as the Earth falls up and meets both objects slightly sooner. With <handwave>appropriate assumptions</handwave>, do they still hit simultaneously, or is there some tiny third-order effect I'm not allowing for?
Nov
23
comment Does Earth's Rotation Affect Its Shape?
@EMACK: I suggest updating your title to reflect exactly what you're asking. Your current title is ambiguous; you could be asking whether the Earth's rotation affects its shape, or how it does so, or why it does so.
Nov
8
revised Americium battery
Typo in title
Oct
30
comment Why does the moon look bigger at the horizon?
en.wikipedia.org/wiki/Moon_illusion
Oct
28
answered If nothing in the universe can travel faster than light, how come light can't escape a black hole?
Oct
26
comment Dropping an object on the moon
And even if that weren't true (if the Moon were somehow stationary at the same distance from the Earth), the Moon's gravity would still be orders of magnitude stronger than the Earth's gravity.
Oct
25
revised Dropping an object on the moon
Add link to hammer-and-feature video
Oct
25
revised Could someone jump from the international space station and live?
MOOSE
Oct
25
awarded  Nice Answer
Oct
23
revised Could someone jump from the international space station and live?
Sorry, forgot about the Vostok capsule
Oct
20
comment Would two astronauts one in a satellite, one on top of a tower have the same experience?
Even if you're standing on the ground at sea level at the equator, your weight is slightly reduced by the rotation of the Earth. On a stationary tower at geosynchronous height, that effect would completely cancel out the force of gravity.
Oct
16
comment How does gravity work?
"How does gravity work?" "Fine, thanks!"
Oct
16
comment Could someone jump from the international space station and live?
@MathewFoscarini: I wasn't asking about the ISS vs. another orbiting object; I was asking about the ISS vs. a stationary platform. Of course no such platform currently exists.
Oct
16
comment Could someone jump from the international space station and live?
Is the question about jumping from the altitude of the ISS, about 400 km, starting at zero ground-relative velocity (say, jumping off a space elevator), or jumping from the ISS itself? The former gives you less velocity to kill, but also less atmosphere to use for braking; the latter gives you a shallow re-entry angle. I don't know which would be easier. Ignoring air resistance, a straight fall from 400 km would take about 5 minutes, with an impact speed of 2800 meters/sec -- much less that the station's orbital speed of 7700 meters/sec.