Category Archives: Physics

From the Earth to Space

Astronomy Picture of the Day: Rocket Launch as Seen from the Space Station. (YouTube, 1:37min) “Video Credit: ISAA, NASA, Expedition 57 Crew (ISS); processing: Riccardo Rossi (ISAA, AstronautiCAST); music: Inspiring Adventure Cinematic Background by Maryna.”

“Have you ever seen a rocket launch — from space? A close inspection of the featured time-lapse video will reveal a rocket rising to Earth orbit as seen from the International Space Station (ISS). The Russian Soyuz-FG rocket was launched ten days ago from the Baikonur Cosmodrome in Kazakhstan, carrying a Progress MS-10 (also 71P) module to bring needed supplies to the ISS. Highlights in the 90-second video (condensing about 15-minutes) include city lights and clouds visible on the Earth on the lower left, blue and gold bands of atmospheric airglow running diagonally across the center, and distant stars on the upper right that set behind the Earth. A lower stage can be seen falling back to Earth as the robotic supply ship fires its thrusters and begins to close on the ISS, a space laboratory that is celebrating its 20th anniversary this month.”

“We’re changing a mass realization system that we’ve had for 129 years”

NPR Science: Say Au Revoir To That Hunk Of Metal In France That Has Defined The Kilogram.

“The world is about to say au revoir to Le Grand K, a cylinder of platinum and iridium that has long reigned over the world’s system of weight measurement.

Le Grand K was forged in 1879 and is held in a locked vault outside Paris — revered and kept under lock and key because its mass, a little over 2 pounds, is the official definition of the kilogram.

But this is will soon change. On Friday, the international General Conference on Weights and Measures will meet in Versailles, France, to vote on whether to redefine the kilogram.

The vote is expected to be unanimous, a mere formality after years of work. Going forward, the world’s system of mass measurement will not be based on some special hunk of metal, but rather on unalterable features of the universe — such as the speed of light, time and Planck’s constant, a number that helps scientists figure out the energy of a photon of light, given its wavelength.”

Minkowski-Diagramme verstehen

Universalthinker: Minkowski-Diagramm 🚀 Spezielle Relativitätstheorie veranschaulicht! (YouTube, 25:30min)

“Möchtest Du spezielle Relativitätstheorie ohne Formeln verstehen, aber Du bist mit der populärwissenschaftlichen Erklärung nicht befriedigt? Dann sind Raum-Zeit-Diagramme (hier: Minkowski-Diagramme) genau das Richtige für Dich! Damit kannst Du alle Phänomene der speziellen Relativitätstheorie (Zeitdilatation, Längenkontraktion) veranschaulichen. Worum geht es im Video genau? In Kurzen Abschnitten wird Dir Folgendes näher gebracht: [22 Punkte]”

Passend dazu gibt’s beim Universaldenker (aka Alexander Fufaev) auch Minkowski-Diagramm: so veranschaulichst Du Relativitätstheorie.

Science Podcast

Motherboard: Science Solved It podcast.

“I grew up on shows like The X-Files and Unsolved Mysteries. I checked out books on UFOs and Bigfoot from the library. I was fascinated by all of the wondrous, unexplainable things in the universe. And I still am. Only now, as an adult, a science journalist, and a skeptic, I’m much more interested in the explanations behind these mysterious phenomena.

That’s why I created Science Solved It, a new weekly podcast from Motherboard. Each episode, I explore one of the world’s greatest mysteries that was solved by science. I talk to the actual, real live scientists who cracked the case, while also indulging in some of the bizarre conspiracy theories that accompany these mysteries. Throughout the season, you’ll hear about unexplained, underwater noises, floating lights, moving rocks, and even a cartoon that gave people seizures.”

I found the podcast via this MetaFilter post: Science Solved It: theories and solutions to strange occurances, which has links and summaries to all the episodes in the first two seasons. I especially liked the episodes about the underwater flies at Mono Lake and the moving rocks in Death Valley, because I’ve been to those places years ago – plus, now I want to go see albino redwood trees (which probably won’t happen, as their location is being kept secret for good reasons).

I’ve got a cold at the moment and spent the past two days on the couch binge-listening to all 14 episodes in the first two seasons. Highly recommended!