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Neptune

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Neptune Position

Neptune is currently in the constellation of Aquarius. The current Right Ascension is 23h 15m 40s and the Declination is -05° 54’ 27”.

23h 15m 40s
-05° 54’ 27”

Simplified sky chart showing where Neptune is right now in the sky with respect to the brightest stars and constellations (see fuillscreen Online Planetarium)

Map showing Neptune in Aquarius on August, 23 2019
Field of view: 60x30 degrees
View fullscreen
 = visible to the naked eye
 = binocular, brighter than 10th magnitude
= current altitude ≥ 30°   = current altitude < 30°   = below the horizon
Location: Greenwich, United Kingdom [change]

Hihgher precision deep sky finder chart showing where Neptune is right now (view fullscreen)

Neptune
RA: 23h 15m 40s
Dec: -05° 54’ 27”
Deep sky finder chart for Neptune
Field of view: 60x40 arcmins
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 4,333,513,993 kilometers, equivalent to 28.967752 Astronomical Units. Light takes 4 hours, 55.0467 seconds to travel from Neptune and arrive to us.

4,333,513,993
28.967752
4 hours, 55.0467 seconds

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.

Distance of Neptune from Earth between January 2013 and December 2049

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:

Tue Oct 29 2041
4,310,539,476
28.814177

NOTE: values for the closest approach are computed with a sampling interval of 1 day.

Neptune brightness

The current visual magnitude of Neptune is 7.82.

7.82
2.3”

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.

Predicted magnitude of Neptune between January 2013 and December 2049

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):

Azimuth: 95.9°
Max altitude: 32.6°
Azimuth: 264.1°
Neptune is above the horizon from Greenwich, United Kingdom

The rise and set times are defined as the time at which the upper limb of Neptune touches the horizon, consideting the effect of the atmospheric refraction. As the atmoshpere 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
2019 Aug 16 23h 16m 23s -05° 49’ 35” 7.82 2.3” Aquarius
2019 Aug 17 23h 16m 18s -05° 50’ 11” 7.82 2.3” Aquarius
2019 Aug 18 23h 16m 14s -05° 50’ 47” 7.82 2.3” Aquarius
2019 Aug 19 23h 16m 08s -05° 51’ 23” 7.82 2.3” Aquarius
2019 Aug 20 23h 16m 01s -05° 52’ 00” 7.82 2.3” Aquarius
2019 Aug 21 23h 15m 56s -05° 52’ 36” 7.82 2.3” Aquarius
2019 Aug 22 23h 15m 51s -05° 53’ 13” 7.82 2.3” Aquarius
2019 Aug 23 23h 15m 46s -05° 53’ 50” 7.82 2.3” Aquarius
2019 Aug 24 23h 15m 39s -05° 54’ 28” 7.82 2.3” Aquarius
2019 Aug 25 23h 15m 33s -05° 55’ 05” 7.82 2.3” Aquarius
2019 Aug 26 23h 15m 28s -05° 55’ 44” 7.82 2.3” Aquarius
2019 Aug 27 23h 15m 21s -05° 56’ 21” 7.82 2.3” Aquarius
2019 Aug 28 23h 15m 16s -05° 57’ 01” 7.82 2.3” Aquarius
2019 Aug 29 23h 15m 11s -05° 57’ 38” 7.82 2.3” Aquarius