The Solar System, on record.
A working orrery and a fact-checked almanac. Every plate carries real figures from NASA's fact sheets; the orbits themselves are a drawing, and the page says so.
Tab to the planetsEnter opens a plateEsc closes
- Orbit spacing & speeds — illustrative, not to scale
- Planet discs — not to scale
- Figures — NASA planetary fact sheets
Mission record
Real missions, real dates — from the first artificial satellite to an infrared observatory parked at Sun–Earth L2.
- 1957
Sputnik 1
The first artificial satellite, launched 4 October 1957; it circled Earth every 96 minutes.
Status: Completed — decayed 1958
- 1969
Apollo 11
First crewed landing on the Moon, 20 July 1969. Two astronauts walked; one kept orbit.
Status: Completed
- 1977
Voyager 2
The only spacecraft to visit all four giant planets, flying them in order from 1979 to 1989.
Status: Operating — interstellar space
- 1977
Voyager 1
Crossed into interstellar space in 2012, the farthest human-made object — and still transmitting.
Status: Operating — interstellar space
- 1997
Cassini–Huygens
Thirteen years orbiting Saturn; the Huygens probe landed on moon Titan in 2005. Ended in 2017.
Status: Completed — deorbited 2017
- 2006
New Horizons
Flew past Pluto on 14 July 2015, returning the first close pictures of the dwarf planet.
Status: Operating — Kuiper Belt
- 2020
Perseverance
Rover in Mars' Jezero Crater since February 2021, sealing rock samples for a future return.
Status: Operating — Mars surface
- 2021
JWST
Infrared observatory stationed at Sun–Earth L2; its first science images arrived July 2022.
Status: Operating — L2 orbit
Scroll the strip — or focus it and use arrow keys.
The archive
One table, eight planets, no invented numbers. Figures transcribed from NASA's planetary fact sheets.
Diameters — equatorial, km
Periods — Earth days unless marked yr
Distances — mean, AU (1 AU = 149.6M km)
Moons — NASA confirmed counts
| Object | Diameter | Orbital period | Mean distance | Moons |
|---|---|---|---|---|
| Mercury | 4,879 km | 88.0 days | 0.39 AU | 0 |
| Venus | 12,104 km | 224.7 days | 0.72 AU | 0 |
| Earth | 12,756 km | 365.2 days | 1.00 AU | 1 |
| Mars | 6,792 km | 687.0 days | 1.52 AU | 2 |
| Jupiter | 142,984 km | 11.9 yr | 5.20 AU | 95 |
| Saturn | 120,536 km | 29.4 yr | 9.54 AU | 274 |
| Uranus | 51,118 km | 84.0 yr | 19.19 AU | 28 |
| Neptune | 49,528 km | 164.8 yr | 30.07 AU | 16 |
Every figure above is real. Only the orrery on this page is illustrative — and it says so.
How to read this almanac
An almanac is only useful if it tells you which parts are measurement and which parts are drawing. Here is the split.
Sourced — measurement
- All planetary figures — diameter, orbital period, mean distance, moon counts — are transcribed from NASA's planetary fact sheets.
- Mission dates and firsts on the mission record are matters of public record.
- The Sun's figures come from NASA's Sun fact sheet.
Illustrative — drawing
- Orbit spacing on the orrery is compressed; true scale would put Neptune roughly 100 Earth-distances out.
- Orbital speeds are slowed, shortened and made regular — they are not the real periods.
- Planet discs are not to scale; Jupiter would need to be about 28 times wider than Mercury.
- Plate art is drawn in code (SVG), not photographed — every plate is captioned as illustrative art.