Watch as pen spinners Ian Jenson and 吳宗諺 (PPM) perform some epic pen spinning, complete with a few great slow motion moments that really showcase what’s going on. This short from Taiwan’s Kuma Films makes us want to get some weighted spinning pens, but anyone can start practicing with an everyday pencil, too: How to Spin a Pencil Around Your Thumb.

Update via LaughingSquid: “PPM is currently competing in the video-based Pen Spinning World Cup 2014, in which he is a semi-finalist.”

In the archives: spinningtricks, and practice.

In a country with economic constraints and limited resources, the bicycle culture of Havana, Cuba has both flourished for its alternative mode of transportation, and struggled as new bikes and repair parts become more and more scarce. But a handful of resourceful mechanics are still trying to keep all kinds of bikes up and running for those who rely on them daily. From Kauri Multimedia, with subtitles: Havana Bikes.

In the archives: London’s table tennis scene and lighthouse keeper Leonardo Da Costa, plus more repairs.

If you’ve ever pretended to be on the Red Planet, you’re not alone. This is Crew 138 of the Mars Society’s Mars Desert Research Station (MDRS), a team of scientists who are researching what it would be like to live on Mars by pretending. From Wikipedia:

The crews usually consist of a mix of astronomers, physicists, biologists, geologists, engineers and the occasional journalist. Each crew member is usually assigned a role: Commander, Executive Officer (ExO), Health and Safety Officer (HSO), Crew Biologist, Crew Geologist or Chief Engineer.

In addition to cooking, cleaning, exercise, HAB maintenance, GreenHab gardening, etc, the crew has mission objectives to complete. A final mission report is written from their notes, analysis, and experiences so that future Mars astronauts and explorers can be well prepared. From National Geographic:

On the mission, the international team is working on in-the-field mapping, collecting and analyzing rock samples, measuring the payoff from exercise, and taking blood samples to monitor crew health. The team is working in mock space suits and testing work protocols indoors and outside.

The first days were largely spent learning to live and work in the Habitat, which is a round two-story structure that measures about 25 feet across.

After the crew enters full simulation, the Habitat contains all the food and water we need, as well as work and sleep quarters.

This team was based in the Utah desert, but there have been other “extraterrestrial” sites: Haughton Crater on Devon Island, and next to the Krafla Rift Volcano in Iceland. There’s also one in the works 324 miles (521 km) north of Adelaide, South Australia. For more information about the project, including volunteer requirements, check out desert.marssociety.org, and read more at National Geographic.

Watch more Mars videos, including a topographically accurate landscapes of Mars and everything Mars Curiosity.

via Devour.

What Does Sound Look Like? NPR’s SkunkBear shows us the differences in fluid densities — in the form of compression waves in a gas, the air that surrounds us — thanks to the light passing through those fluids. Schlieren flow visualization and a high speed video camera make it possible. 

When light travels through areas of different air density, it bends. You’ve probably noticed the way distant pavement seems to shimmer on a hot day, or the way stars appear to twinkle. You’re seeing light that has been distorted as it passes through varying air densities, which are in turn created by varying temperatures and pressures.

Schlieren Flow Visualization can be used to visually capture these changes in density: the rising heat from a candle, the turbulence around an airplane wing, the plume of a sneeze … even sound. 

More seriously amazing physics videos the archives: underwater bubble rings, a fluidized bed of sand, and huge wingtip vortices.