ROOT / SOLAR // DECODED EPHEMERIS: JPL KEPLERIAN · LIVE POSITIONS
Solar // Decoded

The solar system,
where it actually is.

Not a diagram — a computation. Every planet below is placed by solving Kepler's equation from NASA JPL orbital elements, so what you see is where these worlds genuinely are right now, with their true eccentric, inclined orbits. Run time forward, then zoom out past the Kuiper Belt to the galaxy.

8
Planets, live positions
4.6B
Years old
99.8%
Of system mass is the Sun
100k
AU to the Oort Cloud
// Orrery

Live orbital mechanics

Drag to orbit · scroll to zoom · click any world for its data.

Rate ⏪ Reverse ◉ Now ——
Jump to Compressed distances
Orbit paths Labels Asteroid belt Kuiper Belt Comets Milky Way
drag to orbit · scroll to zoom · click a world
✕
Computing ephemeris…

> Positions from JPL approximate Keplerian elements (valid 1800–2050), solved each frame via Kepler's equation. Body sizes are exaggerated to stay visible; distances are compressed by default — switch to true scale to feel how empty space really is.

// The architecture

How the system is built

The Sun holds 99.8% of all mass in the solar system. Everything else — every planet, moon, asteroid and comet — is a rounding error orbiting the leftovers of a molecular cloud that collapsed 4.6 billion years ago.

Inside the snow line, where it was too warm for ice to survive, only rock and metal could condense: Mercury, Venus, Earth and Mars. Beyond it, ice was abundant, so cores grew big enough to capture hydrogen and helium directly from the nebula — that is why Jupiter and Saturn are gas giants, while Uranus and Neptune, forming later and further out, ended up as ice giants rich in water, ammonia and methane.

Past Neptune the Kuiper Belt holds Pluto, Eris, Haumea and Makemake in a ring of frozen volatiles. Beyond that, the Oort Cloud — a spherical shell reaching perhaps 100,000 AU — is the reservoir that occasionally drops a long-period comet back into the inner system. Our nearest star sits at about 268,000 AU.

// Beyond the Sun

Exoplanets: our system is not typical

What 6,160 confirmed worlds taught us about ourselves.

ClassSizeDensity / structureIn our system?
Super-Earths1.2–1.9 R⊕Rocky, bulk density 5–7 g/cm³None
Mini-Neptunes2.0–4.0 R⊕Thick H/He envelope, 0.8–1.5 g/cm³None
Hot JupitersGas giantOrbits inside 0.1 AU; radii inflated up to 20% over modelNone
Terrestrials<1.2 R⊕Rock and metalMercury → Mars
Gas & ice giants4–12 R⊕H/He or water-ammonia-methane icesJupiter → Neptune

The single most important finding is an absence. Super-Earths and mini-Neptunes — worlds between Earth and Neptune in size — are the most common planets in the galaxy, and our solar system has none of them. Whatever process built our system skipped the galaxy's favourite outcome entirely.

The second surprise is spacing. Most multi-planet systems are extremely compact, with several planets orbiting inside 100 days — tighter than Mercury. Ours is unusually spread out, with Jupiter parked at 5.2 AU. Interior models tie the observed mass–radius relation to composition: rocky worlds scale roughly as R ∝ M1/4, while gas-enveloped planets inflate far beyond that, which is how a transit radius and a radial-velocity mass together reveal what a planet is made of without ever seeing its surface.

// Zoom out

The Milky Way and everything above it

Each step up is a structure made of the one below.

Our galaxy

Milky Way

A barred spiral of 100–400 billion stars. The Sun sits about 26,000 light-years out in a spiral arm, orbiting a supermassive black hole — Sagittarius A*, roughly 4.1 million solar masses — once every about 230 million years.

Structure

Disk, bulge, halo

A thin disk of young stars and star-forming gas, a thick disk of older metal-poor stars, and a diffuse stellar halo largely assembled from ancient mergers such as the Gaia-Enceladus collision about 10 billion years ago.

Neighbours

The Local Group

Us, Andromeda, Triangulum and 50+ dwarf galaxies, gravitationally bound. Andromeda is inbound — the two spirals will merge in roughly 4.5 billion years.

Classification

Elliptical (E0–E7)

Smooth ellipsoids of mostly old stars with little gas and almost no ongoing star formation — the end state of repeated galactic mergers.

Classification

Spiral & barred (S / SB)

Disk-dominated with dust-and-gas-rich arms where stars are actively being born. The Milky Way and Andromeda both belong here.

Classification

Irregular (Irr)

No clean symmetry, usually because tidal interaction or a merger tore the structure apart. Many satellite dwarfs are irregular.

Keep zooming and the hierarchy continues: the Local Group is one node of the Laniakea Supercluster, itself a strand of the cosmic web — filaments of galaxies wrapped around vast, nearly empty voids. Every scale on this page, from Mercury's 88-day orbit to a 500-million-light-year supercluster, is the same physics running at a different magnitude.

Sources: Bevelacqua, J. (2021), Solar System Planets and Exoplanets, IntechOpen (doi:10.5772/intechopen.98431) · Spiegel, D. S., Fortney, J. J. & Sotin, C. (2013), Structure of Exoplanets, PNAS 111(39) (doi:10.1073/pnas.1304206111) · NASA JPL approximate ephemerides.

// Frontier dispatch · newest in deep space

An interstellar visitor

For only the third time on record, something from another star passed through.

DEEP SPACE

3I/ATLAS carries water far colder and older than anything born here.

On July 1, 2025 the ATLAS survey in Chile spotted 3I/ATLAS — only the third object ever confirmed to come from outside our solar system, after ʻOumuamua (2017) and Borisov (2019). Moving at roughly 60 km/s on a wildly hyperbolic orbit, it rounded the Sun at perihelion on October 29, 2025 and is now heading back out, passing Jupiter's distance in March 2026.

What makes it remarkable is its chemistry: its water shows a deuterium-to-hydrogen ratio more than 30 times that of comets born in our system, pointing to formation in a far colder, older environment around another star. Hubble, Webb and SPHEREx were all trained on it while there was still time.

> Sources: NASA Science · Sky & Telescope · Hubble/Webb observations.