Explore the Solar System Through Time
Planets are constantly changing position, distance, apparent size and brightness. An ephemeris tells us how those properties change with time.
Four ways to follow a Solar System object
5 November 2026
Compare the brightness, distance, apparent size and sky position of Solar System objects on any date.
| Object | Magnitude | Distance | Apparent size | RA | Dec |
|---|---|---|---|---|---|
| Sun | -26.76 | 0.991914 AU | 1,935.38″ | 14h 39m 04.3s | −15° 29′ 53.2″ |
| Moon | -8.27 | 0.002566 AU | 1,868.70″ | 11h 25m 50.9s | +01° 21′ 11.1″ |
| Mercury | 6.51 | 0.676134 AU | 9.96″ | 14h 35m 08.2s | −15° 26′ 17.9″ |
| Venus | -4.44 | 0.290000 AU | 57.59″ | 13h 23m 34.8s | −12° 57′ 51.1″ |
| Mars | 0.79 | 1.398130 AU | 6.69″ | 09h 32m 46.1s | +16° 20′ 13.9″ |
| Jupiter | -2.03 | 5.322000 AU | 36.25″ | 09h 47m 49.3s | +14° 02′ 45.6″ |
| Saturn | 0.48 | 8.298020 AU | 19.36″ | 00h 36m 02.5s | — |
| Uranus | 5.61 | 18.381100 AU | 3.81″ | 04h 08m 45.1s | +20° 49′ 24.2″ |
| Neptune | 7.70 | 28.972100 AU | 2.35″ | 00h 08m 11.9s | — |
| Ceres | 8.36 | 2.105010 AU | 0.62″ | 07h 39m 28.0s | +24° 10′ 56.6″ |
| Vesta | 6.82 | 1.433700 AU | 0.51″ | 01h 10m 04.0s | −04° 33′ 27.9″ |
| Pluto | 14.59 | 35.606100 AU | 0.09″ | 20h 24m 32.4s | −23° 41′ 13.9″ |
Values are read from the JPL-derived ephemeris data used throughout Show Me The Sky.
Choose an object and explore
How does it change?
Venus — Magnitude
What do these parameters tell us?
Brightness and apparent size
A planet's appearance changes as both its distance and geometry relative to Earth and the Sun change.
The magnitude scale describes apparent brightness, while angular size describes how large an object appears in the sky.
Distance and elongation
One astronomical unit (AU) is approximately the mean Earth–Sun distance.
Elongation measures the apparent angular separation between an object and the Sun. It is especially useful when considering the visibility of Mercury and Venus.
The Solar System is a moving system
A planet does not have one fixed distance, apparent diameter or brightness. Those quantities continually change as Earth and the other planets move around the Sun.
Ephemerides turn that orbital motion into predictions we can use to plan observations and understand what we see through a telescope.
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