Meet your single-celled neighbours – a microbial tour of a metropolis

From an anthropocentric point of view, big cities are one of humanity’s most majestic achievements: massive, self-contained ecosystems built by, catering to, and inhabited by huge numbers of people. But you could forgive microorganisms for claiming that cities are actually theirs. After all, they outnumber humans in urban environments by the trillions. They also affect cityscapes in a far more tangible way: city planners and epidemiologists shape urban environments with pathogenic threats in mind. 

For his experimental short film The Big City, the Canadian filmmaker Evan Luchkow put the hidden lifeforms of downtown Vancouver’s main roads under the literal microscope, documenting the various microbes he found to reveal, in his words, ‘the blurry boundary between human society and the natural world’. The result is an extraordinary and enlightening glimpse of the vast biodiversity with which we share our cities. 

How 3D-printing robots will get Mars home-ready for our arrival

NASA has tentative plans for a manned mission to Mars sometime in the 2030s. Between now and then, there’s still much that needs to be sorted. To start, massive dust storms, high levels of radiation, low temperatures and a lack of water make the Martian surface an unfriendly place for long-term visits. Taming it for human life will likely prove one of the most demanding and complex engineering puzzles in human history. With those extraordinary obstacles in mind, in 2015 NASA announced the 3D-Printed Habitat Challenge: an open call asking designers and architects outside the traditional aerospace industry to create plans for Martian living centred around 3D printing. One of 10 finalists announced in 2019, this plan from the design practices HASSELL and Eckersley O’Callaghan envisions teams of 3D-printing robots building a protective shield on the Martian surface several months in advance of a human landing. Upon arrival, astronauts would then work alongside the autonomous robots to piece together an inflatable, modular habitat.

Frozen for millennia, an ancient Greek soldier is freed to charge into battle once again

The artifacts that underlie so much of our understanding of the ancient world can often feel like brittle remnants of a dim and dusty past that’s hard to access without context and extensive knowledge. But sometimes just a little kineticism can transform a bit of pottery into a living story. Such is the effect of this animation produced for an exhibition at the Ure Museum of Greek Archaeology at the University of Reading in the UK, which breathes life into war scenes from a vase found on the island of Euboea and thought to date to roughly 550 BCE. The story follows a spear-wielding hoplite (citizen-soldier in the infantry) as he moves through several stages of the wartime experience. After witnessing a ceremonial animal sacrifice performed by a priest, he departs for battle alongside his fellow soldiers, fights the enemy and creates a trophy from their discarded equipment to mark his side’s victory. Learn more about the video at the Panoply Vase Animation Project website.

Historic street view: an image for each of the 181 years since the dawn of photography

Just a decade after the first surviving photograph was taken, photography became widespread enough that, today, the Canadian film archivist and YouTuber Guy Jones could assemble this parade of streets worldwide – one photograph for each year from 1838 to 2019. The resulting montage offers a scattershot urban history of modernity, chronicling seismic shifts in transportation methods and fashions, as well as the more subtle evolutions of storefront signage and roadway surfaces. The video also provides a meaningful window into the history of the medium itself. At the dawn of photography, the black-and-white images are deliberately framed, with the camera often drawing the attention of its subjects. In recent photos, as the camera has become more ubiquitous, it’s often less artfully employed, and its presence goes mostly unnoticed by the people whose lives it freezes in discrete moments. 

What wrapping a rope around the Earth reveals about the limits of human intuition

If you tied a rope tight around the Earth’s equator and then added a single yard of slack, would the extra material make any noticeable difference to someone standing on the ground? Yes, actually. The answer comes as a surprise to most people, but the additional bit of rope raises it high enough off the ground for our eyes to easily discern it, and our feet to easily trip over. That fact might seem trivial, but the early 20th-century philosopher Ludwig Wittgenstein believed that this chasm between human intuition and physical reality revealed something important about the fallibility of our thinking. After all, if something that seems obvious to almost everyone can be totally false, what else might we be wrong about? This video from the Center for Public Philosophy at the University of California, Santa Cruz breaks down the mathematics behind Wittgenstein’s knotty example, and asks whether it should make us all feel a bit less certain about even our most deeply held beliefs.