The Random Image Thread (keeping it PG-13 at the worst)

How's life?
User avatar
Geesie
Posts: 26077
Joined: Sat Feb 02, 2008 1:18 am
Title: Couldn't hit it sideways
Location: Searching for my mainline

Post by Geesie »

Image
Image
User avatar
Kirk
Posts: 25939
Joined: Mon Feb 04, 2008 5:09 pm
Location: SLO

Post by Kirk »

I remember those ads and wanting one of those. ;)
User avatar
Geesie
Posts: 26077
Joined: Sat Feb 02, 2008 1:18 am
Title: Couldn't hit it sideways
Location: Searching for my mainline

Post by Geesie »

Here's a fun article from someone who had one:
http://www.comicbookresources.com/?page ... e&id=18236
Image
User avatar
TOS
Posts: 39777
Joined: Mon Jan 21, 2013 5:48 pm

Post by TOS »

"TOS ain’t havin no horserace round here. “Policies” is the coin of the realm." -- iDaemon
DEyncourt
Posts: 17679
Joined: Sun Jan 20, 2008 2:38 am

Post by DEyncourt »

Stunning new technique to accurately map the ocean’s floor via satellites:

Image


So how does this map the seafloor? Get this: If there’s a mountain under the ocean, then it has more gravity than the water around it (rock is denser than water, so it has more mass per cubic centimeter, which means it has more gravity than the same volume of water). This slight increase in gravity draws in water on the surface around it, piling it up on the surface—water is incompressible, so it doesn’t just flatten out. So when the satellite flies over a seamount, it sees a little bump in the sea surface.

If there’s a chasm or trench in the seafloor, then it has slightly lower gravity than the rock around it, so there’s a corresponding dip in the sea surface above it.

Mind you, these bumps and dips in the water surface are tiny, on the order of a millimeter. This is usually completely swamped by currents, waves, chop, and the like. The only way to get good measurements is to take a lot of them, and then the bumps and dips that change over time will cancel out. It’s like flipping a coin; do it a few times and they might all come out heads, but do it a million times and you can be pretty sure you’ll get extremely close to half heads and half tails.

Mind you, these bumps are dips in the water are subtle: They may have a height of several meters, which sounds like a lot, but they’re spread out over a long distance, sometimes hundreds of kilometers. The slope of the water is incredibly small and difficult to measure, and this is complicated by currents, waves, chop, and the like. The satellites have to find that gently sloping trend up (in the case of seamounts) or down (in the case of trenches) despite all that noise. The only way to get good measurements is to take a lot of them, and then the noise that changes over time will cancel out. It’s like flipping a coin; do it a few times and they might all come out heads, but do it a million times and you can be pretty sure you’ll get extremely close to half heads and half tails.**

This was the first thing to amaze me: Scientists can measure the sea surface height to incredible accuracy. The map is based on new techniques that improve the measurements by a factor of two or so.

-----

** Correction, Jan. 14, 2016: Arg! OK, I made a mistake. When I originally wrote this, I said that the measurements had to be accurate on the order of a millimeter to measure the water piling up or flowing away from gravitational anomalies. However, the reality is subtly different: The satellites measure the slopes of the mounds or troughs in the water over great distances to map the topography beneath them. I have to admit: This is even more amazing to me. You're not just looking for a bump in your data that pokes up or down; you're looking for a looooong, slooooow trend, which is in many ways more difficult. So my admiration for this work stand; it just points in a slightly different direction. For more info, read this, and this, and my thanks to Peter Guth for his help.
[links omitted, italics and bold included]

EDIT: added the Bad Astronomer's correction.
Last edited by DEyncourt on Thu Jan 14, 2016 2:07 pm, edited 1 time in total.
User avatar
maurvir
Posts: 25588
Joined: Mon Nov 15, 2010 10:13 pm
Title: Steamed meat popsicle

Post by maurvir »

Stuff like that is why it is so exciting to be alive today. That would have been science fiction just 10 years ago.
User avatar
maurvir
Posts: 25588
Joined: Mon Nov 15, 2010 10:13 pm
Title: Steamed meat popsicle

Post by maurvir »

Image
User avatar
jkahless
Posts: 6504
Joined: Sun Nov 14, 2010 1:09 pm
Title: Custom Title

Post by jkahless »

Heckuvaway to unload some logs eh?
User avatar
Kirk
Posts: 25939
Joined: Mon Feb 04, 2008 5:09 pm
Location: SLO

Post by Kirk »

We had that posted here many pages back I think.
User avatar
ukimalefu
Posts: 45072
Joined: Wed Jan 16, 2008 3:52 pm
Title: DEFCON 5
Location: Failed State

Post by ukimalefu »

Kirk wrote: We had that posted here many pages back I think.


All of these have been posted before and will be posted again

Image
User avatar
TOS
Posts: 39777
Joined: Mon Jan 21, 2013 5:48 pm

Post by TOS »

i often see reposts in this thread

not terribly surprising considering it's been going for almost four years now
"TOS ain’t havin no horserace round here. “Policies” is the coin of the realm." -- iDaemon
User avatar
ukimalefu
Posts: 45072
Joined: Wed Jan 16, 2008 3:52 pm
Title: DEFCON 5
Location: Failed State

Post by ukimalefu »

Image
User avatar
ukimalefu
Posts: 45072
Joined: Wed Jan 16, 2008 3:52 pm
Title: DEFCON 5
Location: Failed State

Post by ukimalefu »

Joan Jett and Lita Ford

Image
User avatar
TOS
Posts: 39777
Joined: Mon Jan 21, 2013 5:48 pm

Post by TOS »

man, they were just kids
"TOS ain’t havin no horserace round here. “Policies” is the coin of the realm." -- iDaemon
User avatar
Geesie
Posts: 26077
Joined: Sat Feb 02, 2008 1:18 am
Title: Couldn't hit it sideways
Location: Searching for my mainline

Post by Geesie »

TOS wrote: man, they were just kids


At least 22 in that picture.
Image
User avatar
ukimalefu
Posts: 45072
Joined: Wed Jan 16, 2008 3:52 pm
Title: DEFCON 5
Location: Failed State

Post by ukimalefu »

Image
User avatar
juice
Posts: 12211
Joined: Wed Jan 23, 2008 12:26 am
Title: Inadvertently correct

Post by juice »

Big Wheel!

My brother and I rode the human waste out of the ones my grandparents got us one Christmas.
User avatar
Geesie
Posts: 26077
Joined: Sat Feb 02, 2008 1:18 am
Title: Couldn't hit it sideways
Location: Searching for my mainline

Post by Geesie »

Image
Image
User avatar
maurvir
Posts: 25588
Joined: Mon Nov 15, 2010 10:13 pm
Title: Steamed meat popsicle

Post by maurvir »

Image

There are times when I really get jealous of Lee Hutchinson...
User avatar
Geesie
Posts: 26077
Joined: Sat Feb 02, 2008 1:18 am
Title: Couldn't hit it sideways
Location: Searching for my mainline

Post by Geesie »

Image
Image
User avatar
obvs
Posts: 27962
Joined: Sat Jan 12, 2008 8:44 pm
Title: Socialist isn't an epithet;it's a badge.

Post by obvs »

Geesie wrote: Image
What does this mean?
DEyncourt
Posts: 17679
Joined: Sun Jan 20, 2008 2:38 am

Post by DEyncourt »

Rings of Saturn near equinox (back in 2009) display perturbations due to tiny moon Daphnis:

Image


This emphasizes the thinness of the rings: Daphnis is only about 8 km in diameter.
User avatar
dv
Posts: 30731
Joined: Wed Jan 16, 2008 3:42 pm

Post by dv »

obvs wrote:
Geesie wrote: Image
What does this mean?


1) Fake mustache.
2) Real mustache, fake fake.
3) Real moustake, fake fake fake, fake hand.
4) Fake girl.

Or, as I read it: If you're one of those mustache-worshipping douchebag hipsters, any girl who seems interested in you and your stick fiddling skinny jeans is probably a reptilian.
Image
User avatar
obvs
Posts: 27962
Joined: Sat Jan 12, 2008 8:44 pm
Title: Socialist isn't an epithet;it's a badge.

Post by obvs »

Is that what was really intended?
User avatar
obvs
Posts: 27962
Joined: Sat Jan 12, 2008 8:44 pm
Title: Socialist isn't an epithet;it's a badge.

Post by obvs »

Image
User avatar
maurvir
Posts: 25588
Joined: Mon Nov 15, 2010 10:13 pm
Title: Steamed meat popsicle

Post by maurvir »

Image
User avatar
maurvir
Posts: 25588
Joined: Mon Nov 15, 2010 10:13 pm
Title: Steamed meat popsicle

Post by maurvir »

Image
User avatar
obvs
Posts: 27962
Joined: Sat Jan 12, 2008 8:44 pm
Title: Socialist isn't an epithet;it's a badge.

Post by obvs »

Where can I get one of those?
User avatar
Kirk
Posts: 25939
Joined: Mon Feb 04, 2008 5:09 pm
Location: SLO

Post by Kirk »

You could 3D print that. ;)
The fixed parts I mean. Motors and slides to make it move are extra.
User avatar
maurvir
Posts: 25588
Joined: Mon Nov 15, 2010 10:13 pm
Title: Steamed meat popsicle

Post by maurvir »

Image
User avatar
maurvir
Posts: 25588
Joined: Mon Nov 15, 2010 10:13 pm
Title: Steamed meat popsicle

Post by maurvir »

Image
User avatar
Kirk
Posts: 25939
Joined: Mon Feb 04, 2008 5:09 pm
Location: SLO

Post by Kirk »

Image
User avatar
DukeofNuke
Posts: 33415
Joined: Mon Jan 21, 2008 1:33 pm
Title: FREE RADICAL
Location: Scintillating!

Post by DukeofNuke »

obvs wrote: Where can I get one of those?


You're not talking about the cake cutter, are you ?
intellectual/hipster/nihilist

"Everyone is entitled to their own opinions, but not their own facts."
-Senator Daniel Patrick Moynihan
User avatar
Kirk
Posts: 25939
Joined: Mon Feb 04, 2008 5:09 pm
Location: SLO

Post by Kirk »

Image
User avatar
maurvir
Posts: 25588
Joined: Mon Nov 15, 2010 10:13 pm
Title: Steamed meat popsicle

Post by maurvir »

Image
User avatar
maurvir
Posts: 25588
Joined: Mon Nov 15, 2010 10:13 pm
Title: Steamed meat popsicle

Post by maurvir »

Image
User avatar
obvs
Posts: 27962
Joined: Sat Jan 12, 2008 8:44 pm
Title: Socialist isn't an epithet;it's a badge.

Post by obvs »

DukeofNuke wrote:
obvs wrote: Where can I get one of those?


You're not talking about the cake cutter, are you ?
Yes, actually I was.
User avatar
Kirk
Posts: 25939
Joined: Mon Feb 04, 2008 5:09 pm
Location: SLO

Post by Kirk »

Awesome truck driving there.

Hah, I figured TEOO was after the cake cutter. ;)
User avatar
Donkey Butter
Posts: 1658
Joined: Sun Nov 14, 2010 8:15 am
Title: jerk face
Location: over yonder

Post by Donkey Butter »

wasn't that cheese that is was cutting?
Post Reply