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July 26, 2021 Archives
Monday, July 26, 2021
CONTEXT: Sabine Hossenfelder: Has Physics Become Too Speculative?
Posted at
15:29
CONTINUITY: Do-It-Yourself Cyanotype Photography
The cyanotype process was invented by astronomer John Herschel in 1842. The chemistry is sensitive only to ultraviolet light, so no darkroom is required. Exposure is usually by sunlight, which contains enough ultraviolet to (very slowly) form an image. This is the process used to make blueprints, and was used for that purpose well into the 20th century.
Posted at
14:47
CONTEXT: The Galileo Project: Scientific Search for Extraterrestrial Artefacts
Here is the home page of The Galileo Project at Harvard University and a description of its three initial areas of research. According to project head, Prof. Avi Loeb of the Harvard astronomy department, more than US$ 1.7 million has been raised from private contributions to support the project.
Posted at
12:12
THE HAPPENING WORLD: After Almost Twenty Years, Pirs Docking Module Departs International Space Station
Pirs, attached to a Progress cargo spacecraft, undocks from the ISS at 6:55 am EDT. pic.twitter.com/d0rB3qLQ0L
— Jeff Foust (@jeff_foust) July 26, 2021
The Pirs module was launched to the International Space Station (ISS) on 2001-09-14. It has supported numerous dockings of Soyuz and Progress craft, and as the airlock for many spacewalks from the Russian segment of the station. It is being towed away from the station by a departing Progress cargo ship, which will deorbit and burn up in the atmosphere later today. The operation frees up the docking port for the Nauka laboratory module, expected to arrive at the station in a few days.
There had been speculation that vacuum welding between the module and its ISS attach point might interfere with undocking, but this has been shown to be unfounded. The attach point will be inspected by cameras on the station's robotic arm to verify it is ready to receive the new module.
Update:
The time has come. At this moment, temperatures are building to unsurvivable levels for #Pirs and #ProgressMS16. The components that do make it will now splash harmlessly into Pacific at ~10:51 EDT / 14:51 UTC.
— Chris G - NSF (@ChrisG_NSF) July 26, 2021
Goodbye, Pirs, and thank you.
ARTICLE: https://t.co/pvknuTsSrM
2021-07-26 19:13 UTC
Posted at
10:59
TRACKING WITH CLOSEUPS: Explaining the Chain Fountain Phenomenon
Why, in particular, does metal ball chain rise over the lip of the container, while other kinds of chains don't?
Posted at
10:45