03 — TERRESTRIAL PLANET
THE COSMIC PERSPECTIVE01 / OUR SOLAR SYSTEM
A little curiosity.
An infinite universe.
Travel beyond the familiar. Discover the worlds
and wonders that make up our cosmic neighborhood.
SOL SYSTEM
LOCAL ARM · MILKY WAY
LOCAL ARM · MILKY WAY
+EARTH · 3D OBSERVATIONARTISTIC MODEL · NOT TO SCALE
DRAG TO ROTATE · SCROLL TO ZOOM
SUN · APPROXIMATE LOCATION
Illustrative arms and star distribution
Illustrative arms and star distribution
CHOOSE YOUR DESTINATIONSun → planets · Moon beside Earth →
SMALL FACTS. BIG PERSPECTIVES.
Earth: a closer look
NEW / THE STELLAR OBSERVATORY
Meet the stars.
Follow their stories.
From cool red dwarfs to dense white dwarfs: discover stellar colors, fusion, and the life cycles that reshape the universe.
THE EXPLORATION ARCHIVE
Small steps.
Historic leaps.
Discover the first satellite, the first spacewalk, lunar exploration, and the observatories that changed our view.
NEW / HUMAN EXPLORATION
Meet the explorers.
And the engineering.
ZOOM OUT / THE MILKY WAY
Your cosmic address.
Earth → Solar system → Orion Spur → Milky Way → Local Group
A city of stars, seen from within.
Our galaxy has a central bar and sweeping spiral arms within a broad disk. The green marker in the model shows an approximate position for the Sun; individual points and arms are illustrative, not a measured star map.
A light-year measures distance: how far light travels in one year. Even light needs about 100,000 years to cross the Milky Way’s stellar disk.
Read about galaxies · NASA ↗THE OBSERVER'S NOTEBOOK
There’s always more
to look up to.
One star. Eight very different worlds.
Mercury, Venus, Earth and Mars are rocky planets. Beyond the asteroid belt lie the gas giants Jupiter and Saturn, then the ice giants Uranus and Neptune. Sizes and distances in this explorer are adjusted for visibility.
Explore NASA’s planet guide ↗Where escape becomes impossible.
A black hole’s event horizon marks the boundary beyond which light cannot escape. The glowing material around some black holes is an accretion disk, heated as matter falls inward.
03 / THE STAR THAT POWERS OUR WORLD
The Sun: light from nuclear fusion.
Deep in the Sun’s core, hydrogen fuses into helium and releases energy. The visible surface is the photosphere; beyond it, the corona extends outward into space. The warm-colored model is an artistic illustration.
Sun facts · NASA ↗04 / OUR CLOSEST COMPANION
The Moon: one world, changing phases.
The Moon shines by reflecting sunlight. Its phases change as we see different portions of its sunlit half during its orbit. It rotates once per orbit, so the same hemisphere faces Earth. Both its near and far sides experience daylight.
Moon facts · NASA ↗