Planetary Gravity: Fall speed and Escape velocity

James O'Donoghue (NASA, JAXA) visualizes gravity effects (spacetime GIF): Fall speeds on different planets (GIF) in our solar system, and escape velocities from the same planets (GIF).

Wetbulb Temperature

Science Advances has a paper on habitable temperatures: At wet-bulb temperature (equivalent to 100% humidity) of above 35° Celsius (308K) a region becomes inhabitable to humans because sweating does not work anymore; higher temperatures are only tolerable with lower humidity. Becomes more relevant with climate change (xkcd).

Ethanol looks like a Dog

An Imgurian shares a drawing of the ethanol (an alcohol variant) molecule looking like a dog: Running, sniffing, eating and sleeping in its cartoon life. Should probably add it to my chemistry intro.

Input Devices: Squeezebox Keyboard

Like the Azeron speedpad, the Squeezebox keyboard prototype has only one row at the bottom, and expands with forward and backward finger clicks; cannot be bought though. The Breeze is a more conventional staggered column keyboard. Both ignore mousing completely. Slightly related: Why keyup on Linux is not easy to program for.

E-Ink Notebook: Build Your Own

Alexander Soto describes the EI2030 project on how to build an e-ink notebook: From the display and drivers, the operating system, to the hardware chassis (e.g. based on OpenBook). Would go nicely with e-ink phones.

Input Device: Azeron Gaming Keypad

Geekhack and PC gamer report on the Azeron Gaming Keypad, a speedpad with only one row but additional forward, backward and occasional side or up clicks. Seems fast, and no chance to misjudge a key anymore. Costs 150 EUR. See also my input device guide.

Radio Garden

An Imgurian links to the Radio Garden, a globe sprinkled with radio stations, all of whom you can listen to. Fascinating to see the sometimes gradual, sometimes abrupt changes in musical taste.

Orbital Mechanics in 60 seconds

An Imgurian shares an animation of orbital mechanics, showing the projected orbit for any amount of acceleration or deceleration: Speeding up to escape earth orbit, then slowing down to get into lunar orbit, instead of just swinging by.

Fanless Mini-PCs: AMD V2000

Liliputing reports on AMD's V2000 "grey hawk" chipset and first fanless mini computers like the iBox V2000: V2516 (6 cores) or V2718 (8 cores) processors around 2GHz, 64GB RAM, unspecified Radeon graphics, in the 25W range. See also my MiniPC guide.


Adam Williams explains booting with UEFI firmware: While BIOS firmware looks at the MBR of attached drives, UEFI looks at the GPT tables of attached drives to find a vfat partition with type identifier EFI, where one or more boot managers reside. Can be configured from within an OS; try e.g. efibootmgr -v for info.

Speed of Light in a GIF

An Imgurian shares a GIF illustrating the speed of light (c=300 Mm/s): 8 times around earth per second, or 1.2 seconds to the moon, or 3 minutes to Mars. Made by James O'Donoghue (NASA, JAXA).

Chemical Elements: What are they good for?

An Imgurian reports on Wlonk Elems, a periodic table where the purpose of each chemical element is briefly explained, by Keith Enevoldsen. Discover magazine also has coverage. See also my chemistry intro.

Lights and Shadows: Rendering

Bartosz Ciechanowski explains light rays and sources with a number of sliders and associated animations, yielding a good visual illustration of what happens during physically based rendering.

Python: Altair for Statistics Visualization

Python has matplotlib as a start to graphs and other number visualization. For statistics Altair may be a good addition. And for meshes PyVista based on VTK.

AMD Mini-PCs (2020)

AMD collects a list of passively cooled mini PCs based on Ryzen processors with integrated VEGA graphics, including BoxPC and iBox. Other models are Maxtang VHFP-30 [de] (V1605B board, 2500U processor, 8G RAM), Zotac ZBox CA622 pro nano [de] (R1505G, proc unknown, 16GB), Lenovo Thinkcentre M75n IoT [de] (board unknown, Silver 3050e, 4GB). See also my MiniPC guide.

The Small Web

Parimal Satyal writes on the "Small Web": Personal websites in the 1990 style neocities, web rings, the personal-only Wiby search, all built by non-commercial enthusiasts with basic HTML. See also my web programming guide.