Oppositions of Neptune until 2037
Dates are in Universal Time. The distance is the one at the instant of opposition. In this list the closest opposition is that of October 20, 2037, at 28.828 AU.
| Opposition | Constellation | Distance | Kilometres | Closest to Earth |
|---|---|---|---|---|
| Pisces | 28.868 AU | 4,318.6 million km | ||
| Pisces | 28.862 AU | 4,317.6 million km | ||
| Pisces | 28.857 AU | 4,316.9 million km | ||
| Pisces | 28.853 AU | 4,316.3 million km | ||
| Pisces | 28.850 AU | 4,315.9 million km | ||
| Pisces | 28.847 AU | 4,315.5 million km | ||
| Pisces | 28.845 AU | 4,315.1 million km | ||
| Pisces | 28.842 AU | 4,314.7 million km | ||
| Pisces | 28.838 AU | 4,314.1 million km | ||
| Pisces | 28.833 AU | 4,313.4 million km | ||
| Pisces | 28.828 AU | 4,312.6 million km |
What happens at opposition
At opposition the Earth passes between Neptune and the Sun: the planet is opposite the Sun in our sky. It rises around sunset, is highest around midnight and sets around sunrise, so it is visible all night.
It is also the time of year when Neptune is nearest and brightest, and when its disc is largest in a telescope. The good observing season lasts for several weeks on either side of the date.
Oppositions come back after one synodic period, the time Earth needs to catch up with the planet again. Around each opposition the planet moves retrograde for a few months.
Frequently asked questions
When is the next opposition of Neptune?
The next opposition of Neptune is on September 28, 2027, in 320 days, in Pisces. Neptune will be 28.868 AU from Earth (4,318.6 million km, 2,683.4 million miles).
How often is Neptune at opposition?
The next ones are on September 28, 2027, September 30, 2028, October 2, 2029 and October 5, 2030. The interval is the synodic period of Neptune.
Is Neptune closest to Earth on the day of opposition?
Within a few days of it. The closest approach is slightly offset from the opposition because the orbits of Earth and Neptune are ellipses; the table gives both dates.