roselabiche:

summery

Roam the whole solar system with little or no energy.

isomorphismes:

To efficiently travel in the solar system (like, using gravity as much as possible and fighting it as little as possible — cf, Dao/wuwei 無爲) you want to weave among these moving pullers like a Tarzan brachiating among the vines.

via @vruba:

It wasn’t so much learning as relearning, but I was delighted the other day when one Peter R. – no, that won’t do; let’s call him P. Richardson – linked to the interplanetary transport network. This is a fluid set of easy paths around the Solar System that has only a very abstract kind of existence but is of first importance if you want to, say, send something to Mars.

Orbital mechanics are way beyond my understanding, but they’re really cool. Twice now I’ve implemented the velocity Verlet integrator, without really getting why it works, to play. Actually, a friend of my family is a mathematician whose entire – quite successful – career is in geometric integration. He’s published a couple dozen papers on, basically, the plusses and minuses of various ways of simulating simple physical systems. It’s all just super neat. Did you know Buzz Aldrin figured out an important Earth-Mars orbit?

A Snapshot of the Inside of an Atom – ScienceNOW

Snapping a picture of the inside of an atom […] is no easy task. […] most attempts to directly observe wave functions actually destroy them in a process called collapse. Physicists at AMOLF […] demonstrated a new nondestructive approach […] the team first fired two lasers at hydrogen atoms inside a chamber, kicking off electrons at speeds and directions that depended on their underlying wave functions. 

A New York aussi il y a eu un El, pas qu’à Chicago

(via Under the El: 1942 | Shorpy Historical Photo Archive)

alaska

marcel dadi