🪐spacetime dept.

New what-if every day

What if…every light on Earth went out? 🌌

Space, but you're actually there. We fly you into black holes, swap our Moon for Saturn and switch off every city, all built from real NASA data and real physics.

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26,000light-years to that glow

80%of Americans can't see it 😳

Saturn would float in a big enough bathtubA day on Uranus pole = 42 yearsTON 618 weighs 40 billion SunsIt might rain diamonds on Uranus 💎Saturn's rings are only ~10 m thickThe Milky Way is above you every night Saturn would float in a big enough bathtubA day on Uranus pole = 42 yearsTON 618 weighs 40 billion SunsIt might rain diamonds on Uranus 💎Saturn's rings are only ~10 m thickThe Milky Way is above you every night

Fan favourites

Start with these. Fair warning: you'll look at the night sky differently.

The Milky Way over a dark street

🌌80% can't see this

What if every light on Earth went out?

Saturn over a street at night

🪐35× wider than the Moon

What if Saturn replaced our Moon?

The black hole TON 618

🕳️40 billion Suns

POV: you fly to the biggest black hole ever

Diamond rain inside Uranus

POV: you fall into Uranus

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Nerd corner 🤓

Every number in our videos, and where it comes from.

Every light on Earth went out

~80% of North Americans can't see the Milky Way from home: Falchi et al., Science Advances (2016).
Full dark adaptation takes about 20–30 minutes.
Street: real 360° photo, Poly Haven (CC0). Milky Way: ESO/S. Brunier (CC BY 4.0), a long exposure; to the eye it looks fainter and greyer.

Saturn replaced our Moon

120,536 km wide; at the Moon's distance it would span 17.9° of sky (the Moon: 0.52°), rings about 40°.
Main rings mostly water ice, typically ~10 m thick. Saturn's density is lower than water's. Day: 10 h 33 min. 274 known moons (2025).
Maps: Solar System Scope (CC BY 4.0). Locations: Poly Haven (CC0). Rendered in Blender.

The biggest black hole ever found

TON 618: about 40 billion solar masses (estimates vary). Event horizon ~1,580 AU across; Neptune's orbit is 60 AU.
Tidal forces at the horizon are tiny at this mass; the longest fall from horizon to centre is πGM/c³, about 7 days.
Rendered with our own light-bending ray-tracer. Deep field: NASA, ESA, S. Beckwith and the HUDF Team (CC BY 4.0).

Falling into Uranus

Tilted 98°; each pole gets ~42 years of daylight. Voyager 2 flew past in 1986. Coldest measured atmosphere: about −224 °C.
Diamonds have formed from hydrocarbons under Uranus-like pressure in lab experiments (SLAC, 2017 and 2022).
Map: Solar System Scope (CC BY 4.0). Space and diamond rain rendered in Blender; the cloud dive is partly AI-generated.