Category Archives: Space

Wie ein Delfin aus dem Wasser springen…

… könnten Menschen, die auf dem Mond schwimmen gehen:

100 Sekunden Physik: Wie ist es auf dem Mond zu schwimmen? (YouTube, 4:52min) “Fast 50 Jahre nach der letzten bemannten Mondmission, rückt der Mond gerade wieder ins Zentrum der Raumfahrt. Da könnte man sich die Frage stellen, wie es sich für einen Astronauten anfühlt in einem See auf dem Mond zu schwimmen?”

Mr. Feynman goes to Washington

BBC: The Challenger Disaster. (YouTube, 1.5 hours)

This movie tells the story of the Space Shuttle Challenger disaster in 1986 and Richard Feynman‘s work in the Rogers Commission.

By the way, you can watch the Presidential Commission on the Space Shuttle Challenger Accident Hearing of February 25, 1986, on YouTube – all 5.5 hours of it. And here is Feynman’s demonstration that the O-rings lose their flexibility in ice water (YouTube, 1:16min).

Kürzlich lief in der ARD eine deutsche Synchronfassung des Films unter dem Titel Challenger – ein Mann kämpft für die Wahrheit. (ARD Mediathe, 1,5 Stunden, verfügbar bis 28.11.2021 05 Uhr)

The chances are about 1 in 100 billion per year

NPR: A meteorite crashes through a home in Canada, barely missing a woman’s head. “It turns out that the 2.8-pound space rock, about the size of a small cabbage, was part of a meteor shower identified by Alan Hildebrand, a planetary scientist in the Department of Geoscience at the University of Calgary, and his colleagues. The group said the trajectory of the meteorite that hit Hamilton’s house would have made it visible throughout southeastern British Columbia and central and southern Alberta.”

Victoria News: B.C. woman awakes to a hole in her roof and a space rock on her pillow.

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Schwarze Löcher

… sind weder schwarz noch Löcher.

Anlässlich der “Black Hole Week” von NASA veröffentlichte Markus Pössel im April auf seinem Blog eine Reihe zu schwarzen Löchern:

Relativ einfach: Woche der Schwarzen Löcher. 1: Sicherheitshinweise, 2: Akkretion, 3: Schattenrisse mit dem Event Horizon Telescope, 4: Wellenschlag mit LIGO, Virgo & Co., 5: Singularitäten als Wissenslücke.

100SekundenPhysik: Wie schwarze Löcher wirklich aussehen. (YouTube, 4min)

“Always do the right thing for the right reason at the right time with the right people. [And] you will have no regrets for the rest of your life.”

NPR Obituaries: Remembering Allan McDonald: He Refused To Approve Challenger Launch, Exposed Cover-Up.

“On Jan. 27, 1986, Allan McDonald stood on the cusp of history.

McDonald directed the booster rocket project at NASA contractor Morton Thiokol. He was responsible for the two massive rockets, filled with explosive fuel, that lifted space shuttles skyward. He was at the Kennedy Space Center in Florida for the launch of the Challenger “to approve or disapprove a launch if something came up,” he told me in 2016, 30 years after Challenger exploded.

His job was to sign and submit an official form. Sign the form, he believed, and he’d risk the lives of the seven astronauts set to board the spacecraft the next morning. Refuse to sign, and he’d risk his job, his career and the good life he’d built for his wife and four children.

“And I made the smartest decision I ever made in my lifetime,” McDonald told me. “I refused to sign it. I just thought we were taking risks we shouldn’t be taking.””

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