Space

The universe is big, old and frankly showing off.

Space makes our everyday sense of scale look rather modest. Planets turn at different speeds, sunlight takes time to reach us, and the material inside a collapsed star behaves nothing like the stuff on your desk. These facts explore the Solar System and the universe beyond it, from observations made by spacecraft to measurements gathered on Earth. Big numbers are useful, but the explanation matters just as much. Where a comparison is theoretical or a measurement is approximate, the story makes that clear. There is plenty of wonder left without turning an estimate into a promise.

All space facts

243 days

A rotation on Venus takes longer than its entire year.

1B tons

A teaspoon of neutron star would weigh about a billion tons.

1969

Apollo footprints can remain on the Moon for thousands of years.

~3T

Earth’s estimated tree count exceeds the Milky Way’s estimated star count.

5x

A bolt of lightning is about five times hotter than the surface of the Sun.

Blue

Sunsets on Mars are blue.

0.69

Saturn is less dense than water, so in theory it would float.

8 min

The sunlight hitting your face right now left the Sun about 8 minutes ago.

176 days

One sunrise-to-sunrise day on Mercury lasts about two Mercury years.

~467°C

Venus is hotter than Mercury even though it is farther from the Sun.

~98°

Uranus rotates almost on its side.

1846

Neptune was predicted mathematically before its confirmed discovery.

5,268 km

Jupiter’s moon Ganymede is wider than Mercury.

Methane rain

Titan has lakes and seas of liquid hydrocarbons.

Hundreds

Io is the solar system’s most volcanically active world.

Ice jets

Enceladus sprays icy material into Saturn’s E ring.

Backward orbit

Triton orbits Neptune opposite the planet’s rotation.

Outside Pluto

Pluto and Charon orbit a shared center outside Pluto.

Asteroid belt

Ceres is the only recognized dwarf planet in the asteroid belt.

~600 km

Olympus Mons is a volcano roughly 600 kilometers across.

Two moons

Mars’s moons are named for fear and panic.

99.8%

The Sun contains about 99.8 percent of the solar system’s mass.

~230 million years

The Sun takes about 230 million years to orbit the Milky Way.

Four ring systems

All four giant planets have rings, not just Saturn.

Hidden ocean

Europa likely hides a saltwater ocean beneath its icy surface.

~3.8 cm/year

The Moon is moving away from Earth by about 3.8 centimeters a year.

Contact binary

An asteroid moon discovered by Lucy is itself a double-lobed object.

Four giants

Voyager 2 is the only spacecraft to have visited all four giant planets.

~1.5 million km

Webb operates near a point about 1.5 million kilometers from Earth.

1992

The first confirmed exoplanets were found around a pulsar.