Neptune
Neptune Position
Neptune is currently in the constellation of Aquarius. The current Right Ascension is 23h 12m 46s and the Declination is -06° 10’ 21”.
Simplified sky chart showing where Neptune is right now in the sky with respect to the brightest stars and constellations (see full screen Online Planetarium)
Higher precision deep sky finder chart showing where Neptune is right now (view fullscreen)
Also check out Where is Neptune?, a page that provides all the information needed to find Neptune in the sky and additional links to sky charts.
Neptune Distance
The distance of Neptune from Earth is currently 4,593,584,539 kilometers, equivalent to 30.706216 Astronomical Units. Light takes 4 hours, 15 minutes and 22.5487 seconds to travel from Neptune and arrive to us.
The following chart shows the distance of Neptune from Earth as a function of time. In the chart the distance data is measured in Astronomical Units and sampled with an interval of 1 day.
The value of the reported distance might be somewhat inaccurate around the times of closest approach for objects passing extremely close to Earth. The value of the distance of Neptune from Earth is also available as a real time updated value in the Live Position and Data Tracker.
Closest approach of Neptune to Earth
Between January 2013 and December 2049 the closest approach of Neptune to Earth happens on Tue Oct 29 2041 at a distance of 28.81417661 Astronomical Units, or 4,310,539,476 kilometers:
NOTE: values for the closest approach are computed with a sampling interval of 1 day.
Neptune brightness
The current visual magnitude of Neptune is 7.95.
The following chart is the predicted light curve (visual magnitude as a function of time) of Neptune, according to the most recent ephemerides data. Magnitude data is sampled with a 2 days interval and there might be inaccuracies for objects changing brightness very rapidly during the course of a few days. For comets there could be large discrepancies between the observed and predicted brightness because of their highly dynamic behaviour.
Neptune rise and set times
Location: Greenwich, United Kingdom [change]
Latitude: 51° 28’ 47” N
Longitude: 0° 00’ 00” E
Timezone: Europe/London
Today's Neptune rise, transit and set times from Greenwich, United Kingdom [change] are the following (all times relative to the local timezone Europe/London):
The rise and set times are defined as the time at which the upper limb of Neptune touches the horizon, considering the effect of the atmospheric refraction. As the atmospheric conditions cannot be modeled precisely the times reported here should be considered correct with an approximation of few minutes.
Neptune Physical Data
The following shows the known values of the most important physical parameters of Neptune. Source: JPL Small-Body Database
| Physical Parameter | Value | Relative to Earth |
|---|---|---|
| Diameter | 49244 km | 3.8647 |
| Mass | 102.41 x 1024 kg | 17.1478 |
| Density | 1.638 gr/cm3 | 0.2971 |
| Escape Velocity | 23.56 km/s | 2.1055 |
| Sideral Rotation | 16.1100 hours | 0.6731 |
| Absolute Magnitude | -6.87 | |
| Geometric Albedo | 0.41 |
Neptune 15 Days Ephemeris
The following table lists the ephemerides of Neptune computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Neptune in our Online Planetarium at the chosen date.
| Date | Right AscensionR.A. | DeclinationDec. | MagnitudeMag | Apparent DiameterDiameter | Constellation |
|---|---|---|---|---|---|
| 2020 Jan 22 | 23h 11m 53s | -06° 15’ 59” | 7.94 | 2.2” | Aquarius |
| 2020 Jan 23 | 23h 12m 01s | -06° 15’ 16” | 7.94 | 2.2” | Aquarius |
| 2020 Jan 24 | 23h 12m 06s | -06° 14’ 35” | 7.94 | 2.2” | Aquarius |
| 2020 Jan 25 | 23h 12m 14s | -06° 13’ 53” | 7.94 | 2.2” | Aquarius |
| 2020 Jan 26 | 23h 12m 20s | -06° 13’ 09” | 7.94 | 2.2” | Aquarius |
| 2020 Jan 27 | 23h 12m 26s | -06° 12’ 26” | 7.94 | 2.2” | Aquarius |
| 2020 Jan 28 | 23h 12m 33s | -06° 11’ 43” | 7.95 | 2.2” | Aquarius |
| 2020 Jan 29 | 23h 12m 41s | -06° 10’ 58” | 7.95 | 2.2” | Aquarius |
| 2020 Jan 30 | 23h 12m 47s | -06° 10’ 14” | 7.95 | 2.2” | Aquarius |
| 2020 Jan 31 | 23h 12m 55s | -06° 09’ 28” | 7.95 | 2.2” | Aquarius |
| 2020 Feb 01 | 23h 13m 01s | -06° 08’ 43” | 7.95 | 2.2” | Aquarius |
| 2020 Feb 02 | 23h 13m 09s | -06° 07’ 57” | 7.95 | 2.2” | Aquarius |
| 2020 Feb 03 | 23h 13m 15s | -06° 07’ 09” | 7.95 | 2.2” | Aquarius |
| 2020 Feb 04 | 23h 13m 23s | -06° 06’ 23” | 7.95 | 2.2” | Aquarius |