Our star — the gravitational anchor of everything you see.
- · 99.86% of the solar system's mass lives here. Surface 5,500 °C, core 15 million °C.
- · Light takes 8 minutes 20 seconds to reach Earth from this point.
NASA's Sun-grazer — the fastest object humans have ever built.
- · Hits 692,000 km/h at perihelion (December 2024) — 0.064% the speed of light.
- · Carbon-foam heat shield endures 1,400 °C while its instruments stay at room temperature behind it.
The innermost planet — fastest orbit, wildest temperature swings.
- · A year here is just 88 Earth days. Surface flips between 430 °C day and -180 °C night.
- · NASA's MESSENGER mapped it 2011-2015. ESA/JAXA's BepiColombo arrives in orbit late 2026.
A runaway-greenhouse hellscape — and Earth's near-twin in size.
- · Surface 465 °C under 92x Earth's pressure. Clouds of sulfuric acid above.
- · Soviet Venera probes landed here in the 1970s. NASA DAVINCI and ESA EnVision launch in the 2030s.
The only world we know that holds life.
- · Atmosphere: 78% nitrogen, 21% oxygen — and the oxygen is biological in origin.
- · A molten iron core generates the magnetic field that deflects solar wind.
Earth's only natural satellite — humans walked here in 1969.
- · 384,400 km away, drifting outward 3.8 cm per year.
- · Tidally locked: the same hemisphere always faces Earth.
Humans live and work here, 400 km above your head, right now.
- · Continuously crewed since November 2000 — humanity has not all been on Earth since.
- · Orbits every ~92 minutes at 27,600 km/h. Sees 16 sunrises a day.
The 1990 telescope that rewrote astronomy — still working 35+ years on.
- · Five Space Shuttle servicing missions (1993-2009) fixed its mirror and upgraded its instruments.
- · Orbits 540 km up. Has logged over 1.6 million observations of the universe.
Today, three working rovers and a helicopter sit on this surface.
- · Olympus Mons is 22 km tall — the largest volcano in the solar system.
- · A Martian day is 24h 37m. Eerily Earth-like.
The largest object in the asteroid belt — a dwarf planet just beyond Mars.
- · 940 km across — about 25% of the asteroid belt's entire mass.
- · NASA's Dawn mission orbited Ceres 2015-2018, finding bright salt deposits and possible briny water.
The largest planet — its Great Red Spot has raged for 350+ years.
- · More massive than every other planet combined, 2.5x over.
- · 101 IAU-recognised moons. Galileo first spotted four of them in 1610.
The most volcanically active body in the solar system — over 400 active volcanoes.
- · Jupiter's gravity flexes Io by 100 m, melting the interior into a sulfur-spewing inferno.
- · NASA's Galileo mapped it in the 1990s. Juno made its closest pass in December 2023.
A moon-wide ocean of liquid water beneath an icy shell.
- · Twice as much liquid water as all of Earth's oceans combined.
- · NASA's Europa Clipper launched in 2024 — arrives 2030 to look for life signatures.
The largest moon in the solar system — bigger than Mercury.
- · The only moon with its own magnetic field, generated by a salty subsurface ocean.
- · ESA's JUICE mission, launched 2023, will orbit Ganymede in 2034 — a first for any moon.
The most heavily cratered surface in the solar system — a 4-billion-year fossil.
- · Geologically dead since the early solar system. Every impact since is still recorded here.
- · A subsurface ocean may sit 250 km down. Lowest radiation of Jupiter's big moons.
Its rings are mostly water ice — and only ~10 m thick.
- · 274 confirmed moons — by far the most of any planet (jumped from 146 in 2025).
- · Density less than water — Saturn would float in a (cosmically large) bathtub.
A 500 km moon venting the contents of a salty subsurface ocean to space.
- · Cassini flew through the south-polar plumes and detected hydrogen, organics, and salts — every ingredient for life chemistry.
- · Brightest body in the solar system: 99% of incoming sunlight reflects back off the fresh-ice surface.
The only moon with a thick atmosphere — and it rains methane.
- · Lakes and rivers of liquid methane and ethane cover the surface.
- · Surface pressure is 1.45x Earth's. With strapped-on wings, you could fly.
Tipped on its side — its rotation axis is tilted 98°.
- · Each pole gets 42 years of continuous sunlight, then 42 years of darkness.
- · Coldest planetary atmosphere in the solar system: -224 °C.
Winds reach 2,100 km/h — fastest in the solar system.
- · Voyager 2 is still our only visitor. Last pass: 1989.
- · Discovered by math first — predicted from Uranus's orbital anomalies in 1846.
Neptune's largest moon — a captured Kuiper-Belt object orbiting backward.
- · Active nitrogen geysers caught mid-eruption by Voyager 2 in 1989 — one of only a handful of geologically alive bodies known.
- · In ~3.6 billion years tidal forces will break Triton apart into a Saturn-style ring around Neptune.
Reclassified as a dwarf planet in 2006 — but still the king of the outer system.
- · A year on Pluto is 248 Earth years. Surface temperature: -230 °C.
- · NASA's New Horizons flew past in July 2015, revealing nitrogen-ice glaciers and an atmosphere.
Pluto's partner moon — half its diameter, locked in a perpetual gravitational dance.
- · Pluto and Charon orbit a common centre of gravity above Pluto's surface — a true binary system.
- · New Horizons revealed a reddish polar cap (Mordor Macula) made of tholins blown over from Pluto's atmosphere.
Humanity's farthest emissary — 163 AU out and still phoning home.
- · Crossed into interstellar space in August 2012 — the first human-made object to do so.
- · Carries the Golden Record: greetings in 55 languages, music, and Earth sounds, in case anyone's listening.
The grand-tour craft — the only spacecraft to have visited Uranus and Neptune.
- · Launched 16 days before Voyager 1 in 1977. Flew past all four giant planets between 1979 and 1989.
- · Crossed the heliopause into interstellar space in November 2018, six years after Voyager 1.
China's modular space station — fully assembled in 2022, continuously crewed.
- · Three modules: Tianhe core (2021), Wentian and Mengtian labs (2022). Roughly 20% the mass of the ISS.
- · Orbits 340-450 km up. Six-month crew rotations of three taikonauts via Shenzhou capsules.
Our newest eyes — sees the universe in infrared from 1.5 million km away.
- · 6.5 m gold-coated mirror, 18 hexagonal segments. Operates at -223 °C.
- · Has photographed galaxies from when the universe was just 280 million years old.