Wednesday, January 27, 2021

SpaceX's Record Breaking* Rideshare Mission Launches 143 Satellites

* Before viewing, can you guess which previous mission launched more objects into orbit in a single launch?

Posted at 13:35 Permalink

Tuesday, January 26, 2021

How Many Ways Can You Make Change for a Googol Dollars?

This problem is presented in Concrete Mathematics by Graham, Knuth, and Patashnik.

Posted at 14:36 Permalink

Sunday, January 24, 2021

Lunar Lander that Makes its Own Landing Pad

Posted at 21:24 Permalink

Saturday, January 23, 2021

Three Hours of Conversation on Physics, Theories of Everything, and Doing Research outside Academia

With Brian Keating (host), Garrett Lisi (developer of the E8 theory of fundamental physics), and Eric Weinstein (in the second two hours).

Posted at 14:11 Permalink

Thursday, January 21, 2021

Tensegrity Structures Explained

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Wednesday, January 20, 2021

Virgin Reaches Orbit with the Help of Cosmic Girl

Scott Manley wraps up Virgin Orbit's successful air launch mission.

Posted at 13:14 Permalink

Tuesday, January 19, 2021

Secrets of the “Nothing Grinder”

Posted at 13:18 Permalink

Sunday, January 17, 2021

First Full Test of SLS Booster Fails as Engines Trigger Emergency Shutdown

Here is Scott Manley's quick look analysis of the SLS test firing abort. He notes that in 2020, there was discussion about skipping the “green run” test and proceeding directly to launch. Had they done that, it might have been a really bad day for SLS (but at least the first launch will not carry a crew, although that was also considered in 2020, as part of the push to return to the Moon by 2024).

Posted at 21:17 Permalink

Saturday, January 16, 2021

I Painted My Entire Room with Musou Black—the World’s Blackest Paint

Posted at 14:04 Permalink

Friday, January 15, 2021

Mathematicians Resurrect Hilbert’s 13th Problem

Did you know that every smooth cubic surface contains exactly 27 straight lines?

Posted at 12:24 Permalink

Thursday, January 14, 2021

LED Lamps from Dubai: They Leave the West Behind

Only sold in Dubai: Philips LED lamps that use more LED chips running at lower current, resulting in greater efficiency (light output per electrical power consumed) and much longer life. The initial cost is higher, but the longer life will probably more than recover this. There's an internal voltage regulator which keeps the lamps from dimming or brightening when the mains voltage varies (but means they won't work with dimmers).

Posted at 15:55 Permalink

Wednesday, January 13, 2021

The Many Forms of Brassica oleracea

And don't forget Brassica’s wacky fractal sibling, Romanesco!

Posted at 13:06 Permalink

Tuesday, January 12, 2021

Exploding Hardened Steel Parts with 150 Ton Hydraulic Press

Posted at 13:09 Permalink

Monday, January 11, 2021

Moon Phases in 2021 (Including Libration and Position Angle)

For additional details, see my:

Posted at 12:06 Permalink

Thursday, January 7, 2021

Vacuum Tubes: Getting Familiar with Getters

More about getters.

Posted at 16:20 Permalink

Monday, January 4, 2021

Thunderstorm Sprite Lightning at 100,000 Frames per Second

Details from Astronomy Picture of the Day.

Posted at 19:51 Permalink

Tighten This Bolt in Any Direction You Want

Posted at 14:32 Permalink

Saturday, January 2, 2021

Extracting Potassium Metal from Bananas

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Friday, January 1, 2021

How SpaceX Recovers Falcon 9 after Drone Ship Landings

Posted at 15:18 Permalink

Thursday, December 31, 2020

Understanding Synthetic Aperture Radar

Posted at 13:31 Permalink