Orrery · JPL Keplerian elements
The dance of the planets, 1900 to 2050
Run time forward: at each opposition, conjunction or greatest elongation, a line goes from the Earth to the planet.
- Mercury
- Venus
- Mars
- Jupiter
- Saturn
- Uranus
- Neptune
- Earth
Next event
Inferior conjunction
Mars at its closest
2027-02-20
Planets visible tonight
5
Positions computed from the approximate Keplerian elements of JPL (Standish), valid 1800–2050, to a few arcminutes. Distances compressed (about √) so that Mercury and Neptune fit in one view; sizes not to scale. Seen from the north of the ecliptic: the planets turn counter-clockwise.
Seen from the Earth, the planets seem to wander among the stars: that is the meaning of the Greek word planêtês. Their dance comes from two combined motions, their own around the Sun and that of the Earth. This page computes their positions for any date between 1900 and 2050 and derives the coming events: oppositions (the planet facing the Sun, visible all night, at its closest), conjunctions (the planet behind or in front of the Sun, invisible), greatest elongations of Mercury and Venus (the best time to see them), close pairings of planets in the sky. The computed dates were checked against the JPL Horizons ephemerides.
Where the planets are tonight (2026-10-29)
5 planets are far enough from the Sun in the sky (more than 15°) to be looked for. “Evening”: east of the Sun, visible after sunset; “morning”: west, before sunrise; “all night”: near opposition. Uranus needs binoculars, Neptune a telescope.
| Planet | Visibility | Distance from the Sun in the sky | Distance from the Earth | Light travel time | Apparent diameter |
|---|---|---|---|---|---|
| Mercury | Lost in the glare of the Sun | 14° East | 0.712 au | 5.9 min | 9.4″ |
| Venus | Lost in the glare of the Sun | 10° West | 0.275 au | 2.3 min | 60.7″ |
| Mars | Morning sky | 78° West | 1.457 au | 12.1 min | 6.4″ |
| Jupiter | Morning sky | 72° West | 5.543 au | 46.1 min | 35.6″ |
| Saturn | All night | 154° East | 8.524 au | 1.2 h | 19.5″ |
| Uranus | All night | 151° West | 18.558 au | 2.6 h | 3.8″ |
| Neptune | Evening sky | 147° East | 29.043 au | 4.0 h | 2.4″ |
Events of the next three years
Dates in Universal Time, to about half a day (compared with JPL Horizons). Pairings of two planets are listed only when they pass within 2° of each other; “invisible” marks a conjunction with the Sun.
| Date | Event | Planet | Detail |
|---|---|---|---|
| 2026-11-04 | Inferior conjunction | Mercury | 0.674 au (100.8 million km), apparent diameter 10.0″ |
| 2026-11-16 | Pairing of two planets | Mars – Jupiter | 1.2° apart; 88° from the Sun (West) |
| 2026-11-20 | Greatest morning elongation | Mercury | 19.6° from the Sun in the sky |
| 2026-11-25 | Opposition | Uranus | 18.439 au (2,758.4 million km), apparent diameter 3.8″ |
| 2027-01-01 | Superior conjunction | Mercury | invisible, in the direction of the Sun |
| 2027-01-03 | Greatest morning elongation | Venus | 47.0° from the Sun in the sky |
| 2027-02-03 | Greatest evening elongation | Mercury | 18.3° from the Sun in the sky |
| 2027-02-11 | Opposition | Jupiter | 4.359 au (652.1 million km), apparent diameter 45.2″ |
| 2027-02-18 | Inferior conjunction | Mercury | 0.644 au (96.3 million km), apparent diameter 10.5″ |
| 2027-02-19 | Opposition | Mars | 0.678 au (101.4 million km), apparent diameter 13.8″ |
| 2027-02-20 | Closest to the Earth | Mars | 0.678 au (101.4 million km), apparent diameter 13.8″ |
| 2027-03-17 | Greatest morning elongation | Mercury | 27.6° from the Sun in the sky |
| 2027-03-24 | Conjunction with the Sun | Neptune | invisible, in the direction of the Sun |
| 2027-04-07 | Conjunction with the Sun | Saturn | invisible, in the direction of the Sun |
| 2027-04-11 | Pairing of two planets | Mercury – Neptune | 1.0° apart; 17° from the Sun (West) |
| 2027-04-19 | Pairing of two planets | Mercury – Saturn | 0.6° apart; 10° from the Sun (West) |
| 2027-04-24 | Pairing of two planets | Venus – Neptune | 0.2° apart; 29° from the Sun (West) |
| 2027-04-28 | Superior conjunction | Mercury | invisible, in the direction of the Sun |
| 2027-05-07 | Pairing of two planets | Venus – Saturn | 0.6° apart; 26° from the Sun (West) |
| 2027-05-11 | Pairing of two planets | Mercury – Uranus | 1.9° apart; 14° from the Sun (East) |
| 2027-05-27 | Conjunction with the Sun | Uranus | invisible, in the direction of the Sun |
| 2027-05-28 | Greatest evening elongation | Mercury | 22.9° from the Sun in the sky |
| 2027-06-14 | Pairing of two planets | Venus – Uranus | 0.7° apart; 16° from the Sun (West) |
| 2027-06-23 | Inferior conjunction | Mercury | 0.556 au (83.2 million km), apparent diameter 12.1″ |
| 2027-07-15 | Greatest morning elongation | Mercury | 20.7° from the Sun in the sky |
| 2027-08-11 | Pairing of two planets | Mercury – Venus | 0.5° apart; 2° from the Sun (West) |
| 2027-08-11 | Superior conjunction | Mercury | invisible, in the direction of the Sun |
| 2027-08-11 | Superior conjunction | Venus | invisible, in the direction of the Sun |
| 2027-08-19 | Pairing of two planets | Mercury – Jupiter | 0.6° apart; 9° from the Sun (East) |
| 2027-08-26 | Pairing of two planets | Venus – Jupiter | 0.5° apart; 4° from the Sun (East) |
| 2027-08-31 | Conjunction with the Sun | Jupiter | invisible, in the direction of the Sun |
| 2027-09-24 | Greatest evening elongation | Mercury | 26.3° from the Sun in the sky |
| 2027-09-28 | Opposition | Neptune | 28.869 au (4,318.8 million km), apparent diameter 2.4″ |
| 2027-10-18 | Opposition | Saturn | 8.329 au (1,246.0 million km), apparent diameter 20.0″ |
| 2027-10-19 | Inferior conjunction | Mercury | 0.668 au (99.9 million km), apparent diameter 10.1″ |
| 2027-11-04 | Greatest morning elongation | Mercury | 18.8° from the Sun in the sky |
| 2027-11-25 | Pairing of two planets | Venus – Mars | 0.3° apart; 27° from the Sun (East) |
| 2027-11-30 | Opposition | Uranus | 18.374 au (2,748.7 million km), apparent diameter 3.8″ |
| 2027-12-11 | Superior conjunction | Mercury | invisible, in the direction of the Sun |
| 2028-01-08 | Pairing of two planets | Mercury – Mars | 0.7° apart; 16° from the Sun (East) |
| 2028-01-17 | Greatest evening elongation | Mercury | 18.8° from the Sun in the sky |
| 2028-02-02 | Inferior conjunction | Mercury | 0.657 au (98.3 million km), apparent diameter 10.2″ |
| 2028-02-11 | Pairing of two planets | Venus – Neptune | 1.2° apart; 42° from the Sun (East) |
| 2028-02-27 | Greatest morning elongation | Mercury | 26.9° from the Sun in the sky |
| 2028-03-12 | Opposition | Jupiter | 4.440 au (664.2 million km), apparent diameter 44.4″ |
| 2028-03-21 | Conjunction with the Sun | Mars | invisible, in the direction of the Sun |
| 2028-03-22 | Greatest evening elongation | Venus | 46.1° from the Sun in the sky |
| 2028-03-26 | Conjunction with the Sun | Neptune | invisible, in the direction of the Sun |
| 2028-03-28 | Pairing of two planets | Mars – Neptune | 0.6° apart; 2° from the Sun (West) |
| 2028-04-04 | Pairing of two planets | Mercury – Neptune | 0.4° apart; 8° from the Sun (West) |
| 2028-04-08 | Pairing of two planets | Mercury – Mars | 0.6° apart; 4° from the Sun (West) |
| 2028-04-11 | Superior conjunction | Mercury | invisible, in the direction of the Sun |
| 2028-04-20 | Conjunction with the Sun | Saturn | invisible, in the direction of the Sun |
| 2028-05-01 | Pairing of two planets | Mars – Saturn | 1.8° apart; 9° from the Sun (West) |
| 2028-05-09 | Greatest evening elongation | Mercury | 21.4° from the Sun in the sky |
| 2028-05-30 | Conjunction with the Sun | Uranus | invisible, in the direction of the Sun |
| 2028-06-01 | Inferior conjunction | Venus | 0.288 au (43.1 million km), apparent diameter 57.9″ |
| 2028-06-02 | Inferior conjunction | Mercury | 0.549 au (82.1 million km), apparent diameter 12.3″ |
| 2028-06-03 | Pairing of two planets | Venus – Uranus | 0.4° apart; 3° from the Sun (West) |
| 2028-06-23 | Pairing of two planets | Mars – Uranus | 0.2° apart; 22° from the Sun (West) |
| 2028-06-26 | Greatest morning elongation | Mercury | 22.2° from the Sun in the sky |
| 2028-07-25 | Superior conjunction | Mercury | invisible, in the direction of the Sun |
| 2028-08-10 | Greatest morning elongation | Venus | 45.8° from the Sun in the sky |
| 2028-09-06 | Greatest evening elongation | Mercury | 27.1° from the Sun in the sky |
| 2028-09-30 | Opposition | Neptune | 28.864 au (4,317.9 million km), apparent diameter 2.4″ |
| 2028-09-30 | Conjunction with the Sun | Jupiter | invisible, in the direction of the Sun |
| 2028-10-02 | Inferior conjunction | Mercury | 0.658 au (98.4 million km), apparent diameter 10.2″ |
| 2028-10-17 | Greatest morning elongation | Mercury | 18.2° from the Sun in the sky |
| 2028-10-22 | Pairing of two planets | Mercury – Jupiter | 1.0° apart; 17° from the Sun (West) |
| 2028-10-30 | Opposition | Saturn | 8.233 au (1,231.6 million km), apparent diameter 20.2″ |
| 2028-11-10 | Pairing of two planets | Venus – Jupiter | 0.6° apart; 32° from the Sun (West) |
| 2028-11-20 | Superior conjunction | Mercury | invisible, in the direction of the Sun |
| 2028-12-03 | Opposition | Uranus | 18.307 au (2,738.7 million km), apparent diameter 3.8″ |
| 2028-12-31 | Greatest evening elongation | Mercury | 19.6° from the Sun in the sky |
| 2029-01-16 | Inferior conjunction | Mercury | 0.667 au (99.8 million km), apparent diameter 10.1″ |
| 2029-02-09 | Greatest morning elongation | Mercury | 25.7° from the Sun in the sky |
| 2029-03-23 | Superior conjunction | Venus | invisible, in the direction of the Sun |
| 2029-03-25 | Opposition | Mars | 0.649 au (97.1 million km), apparent diameter 14.4″ |
| 2029-03-26 | Superior conjunction | Mercury | invisible, in the direction of the Sun |
| 2029-03-27 | Pairing of two planets | Mercury – Venus | 0.2° apart; 2° from the Sun (East) |
| 2029-03-27 | Pairing of two planets | Mercury – Neptune | 0.4° apart; 2° from the Sun (East) |
| 2029-03-27 | Pairing of two planets | Venus – Neptune | 0.1° apart; 2° from the Sun (East) |
| 2029-03-28 | Conjunction with the Sun | Neptune | invisible, in the direction of the Sun |
| 2029-03-29 | Closest to the Earth | Mars | 0.647 au (96.8 million km), apparent diameter 14.5″ |
| 2029-04-12 | Opposition | Jupiter | 4.450 au (665.7 million km), apparent diameter 44.3″ |
| 2029-04-21 | Greatest evening elongation | Mercury | 20.1° from the Sun in the sky |
| 2029-04-24 | Pairing of two planets | Venus – Saturn | 1.6° apart; 8° from the Sun (East) |
| 2029-05-04 | Conjunction with the Sun | Saturn | invisible, in the direction of the Sun |
| 2029-05-05 | Pairing of two planets | Mercury – Venus | 1.8° apart; 11° from the Sun (East) |
| 2029-05-12 | Inferior conjunction | Mercury | 0.555 au (83.0 million km), apparent diameter 12.1″ |
| 2029-05-19 | Pairing of two planets | Venus – Uranus | 0.4° apart; 15° from the Sun (East) |
| 2029-06-04 | Conjunction with the Sun | Uranus | invisible, in the direction of the Sun |
| 2029-06-08 | Greatest morning elongation | Mercury | 23.9° from the Sun in the sky |
| 2029-06-23 | Pairing of two planets | Mercury – Uranus | 1.2° apart; 17° from the Sun (West) |
| 2029-07-09 | Superior conjunction | Mercury | invisible, in the direction of the Sun |
| 2029-07-19 | Pairing of two planets | Mars – Jupiter | 1.6° apart; 82° from the Sun (East) |
| 2029-08-19 | Greatest evening elongation | Mercury | 27.4° from the Sun in the sky |
| 2029-09-07 | Pairing of two planets | Venus – Jupiter | 1.7° apart; 42° from the Sun (East) |
| 2029-09-15 | Inferior conjunction | Mercury | 0.644 au (96.4 million km), apparent diameter 10.4″ |
| 2029-10-01 | Greatest morning elongation | Mercury | 17.9° from the Sun in the sky |
| 2029-10-02 | Opposition | Neptune | 28.858 au (4,317.1 million km), apparent diameter 2.4″ |
| 2029-10-27 | Greatest evening elongation | Venus | 47.0° from the Sun in the sky |
Oppositions of Mars, 1990–2050: apparent size at closest approach
The loop of Mars around its opposition of 2027-02-19
Kepler’s third law
Orbital periods and returns seen from the Earth
The sidereal period is the time of one turn around the Sun; the synodic period, the interval between two oppositions (or two inferior conjunctions) seen from the Earth: 1/S = |1/P − 1/PEarth|. Mars comes back to opposition about every 780 days; Jupiter and Saturn almost every year, as the Earth soon catches them up.
| Planet | Sidereal period (years) | Synodic period (days) |
|---|---|---|
| Mercury | 0.24 | 116 |
| Venus | 0.62 | 584 |
| Mars | 1.88 | 780 |
| Jupiter | 11.86 | 399 |
| Saturn | 29.45 | 378 |
| Uranus | 84.02 | 370 |
| Neptune | 164.79 | 368 |
Method and sources
Positions. Approximate Keplerian elements of the planets from JPL (Standish), valid 1800–2050: semi-major axis, eccentricity, inclination, mean longitude, longitudes of perihelion and node at J2000, and their drift per century. Kepler’s equation is solved by Newton iterations; heliocentric positions in the ecliptic J2000 frame. The “Earth” of these elements is the Earth–Moon barycentre (4,700 km from the centre of the Earth, no effect here).
Events. Geocentric ecliptic longitude and latitude of each planet and of the Sun computed day by day, then refined by bisection to the minute: conjunction when the longitude of the planet equals that of the Sun, opposition at 180° (almanac definitions, in longitude); inferior or superior conjunction of Mercury and Venus by their distance; greatest elongation at the maximum of the Sun–Earth–planet angle; closest distance of Mars to the Earth; pairing of two planets when their longitudes are equal, with their true separation on the sky. Geometric positions, without light time, aberration or nutation; Universal Time without ΔT (about 69 s).
Check. The dates from 2020 to 2027 (Jupiter–Saturn great conjunction of 21/12/2020, oppositions of Mars in 2022, 2025 and 2027, of Jupiter and Saturn, elongations of Venus) agree with JPL Horizons and the almanacs to within half a day; the closest distance of Mars on 20/02/2027 (0.6779 au) is that of Horizons to 10⁻⁴ au.
Reading these data
The approximate elements are only valid from 1800 to 2050 and give positions to a few arcminutes: enough for the dates of events, not for pointing a telescope or predicting an occultation. Dates are in Universal Time. Being “in the evening sky” says nothing about the height above the horizon, which depends on the place and the season; 15° from the Sun is a minimum, often not enough for Mercury. Distances and sizes on the 3D globe are not to scale.
SOURCES OF THIS PAGE
- Standish, E. M. (1992, revised). Keplerian Elements for Approximate Positions of the Major Planets. JPL Solar System Dynamics (ssd.jpl.nasa.gov/planets/approx_pos.html), valid 1800–2050.
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Standish, E. M. (1992, revised). Keplerian Elements for Approximate Positions of the Major Planets. JPL Solar System Dynamics (ssd.jpl.nasa.gov/planets/approx_pos.html), valid 1800–2050.
Licence : Published literature; cited - Meeus (1998)
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Meeus, J. (1998). Astronomical Algorithms (2nd ed.). Willmann-Bell, Richmond.
Licence : Published literature; cited - Giorgini et al. (1996)
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Giorgini, J. D., Yeomans, D. K., Chamberlin, A. B., et al. (1996). JPL’s On-Line Solar System Data Service. Bulletin of the American Astronomical Society, 28, 1158 (Horizons, used to check the dates).
Licence : Published literature; cited