Neptune
Neptune Position
Neptune is currently in the constellation of Aquarius. The current Right Ascension is 23h 21m 57s and the Declination is -05° 12’ 37”.
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 4,608,803,680 kilometers, equivalent to 30.807950 Astronomical Units. Light takes 4 hours, 16 minutes and 13.3143 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 28.81417655 Astronomical Units, or 4,310,539,467 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 Mar 31 | 23h 21m 00s | -05° 18’ 28” | 7.96 | 2.2” | Aquarius |
| 2020 Apr 01 | 23h 21m 07s | -05° 17’ 39” | 7.96 | 2.2” | Aquarius |
| 2020 Apr 02 | 23h 21m 15s | -05° 16’ 50” | 7.96 | 2.2” | Aquarius |
| 2020 Apr 03 | 23h 21m 24s | -05° 16’ 00” | 7.96 | 2.2” | Aquarius |
| 2020 Apr 04 | 23h 21m 32s | -05° 15’ 12” | 7.96 | 2.2” | Aquarius |
| 2020 Apr 05 | 23h 21m 39s | -05° 14’ 25” | 7.96 | 2.2” | Aquarius |
| 2020 Apr 06 | 23h 21m 47s | -05° 13’ 36” | 7.95 | 2.2” | Aquarius |
| 2020 Apr 07 | 23h 21m 55s | -05° 12’ 50” | 7.95 | 2.2” | Aquarius |
| 2020 Apr 08 | 23h 22m 02s | -05° 12’ 02” | 7.95 | 2.2” | Aquarius |
| 2020 Apr 09 | 23h 22m 09s | -05° 11’ 16” | 7.95 | 2.2” | Aquarius |
| 2020 Apr 10 | 23h 22m 18s | -05° 10’ 29” | 7.95 | 2.2” | Aquarius |
| 2020 Apr 11 | 23h 22m 24s | -05° 09’ 44” | 7.95 | 2.2” | Aquarius |
| 2020 Apr 12 | 23h 22m 32s | -05° 08’ 58” | 7.95 | 2.2” | Aquarius |
| 2020 Apr 13 | 23h 22m 40s | -05° 08’ 13” | 7.95 | 2.2” | Aquarius |