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🌎 Location: Greenwich, United Kingdom [change]

Neptune

Neptune is currently in the constellation of Aquarius. The current Right Ascension of Neptune is 23h 25m 34s and the Declination is -04° 54’ 38” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom [change]). The current magnitude of Neptune is 7.83 (JPL).

Summary of key facts about Neptune [tip: you can also create a Quick Access page for this data if you access it frequently and would like to have a simpler view]:

23h 25m 34s
-04° 54’ 38”
Aquarius
7.83
  • Neptune is above the horizon from Greenwich, United Kingdom [change].
  • It is visible looking in the South-South-West direction at an altitude of 31° above the horizon.
  • Given its current magnitude, Neptune is visible with the help of a binocular with a 30-40mm aperture, easy with a small telescope.
  • See also Neptune rise and set times.
  • Go to interactive sky chart

If you need to access this information frequently for your observations, you can create a simple customized Quick Access page, so that you can easily bookmark it in your browser favorites or add a shortcut to your mobile phones' home screen.

Additional information about Neptune available on TheSkyLive:

Available Resources

Neptune Position and Finder Charts

Below we provide Neptune finder charts showing where the object is right now in the sky with respect to the brightest stars. The first finder chart has a field of view of 50 degrees, while the second one has a field of view of 10 degrees. Click on each finder chart to access a full screen interactive Online Planetarium.

Map showing Neptune in Aquarius on August, 07 2020
Field of view: 50x30 degrees
View fullscreen
Map showing Neptune in Aquarius on August, 07 2020
Field of view: 10x6 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]

Higher precision deep sky finder chart, 60 arcmin wide, showing where Neptune is right now. Click on the image to see a more detailed fullscreen tracker view.

Neptune
RA: 23h 25m 34s
Dec: -04° 54’ 38”
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 from Earth

The distance of Neptune from Earth is currently 4,352,773,991 kilometers, equivalent to 29.096497 Astronomical Units. Light takes 4 hours, 1 minutes and 59.2912 seconds to travel from Neptune and arrive to us.

4,352,773,991
29.096497
4 hours, 1 minutes and 59.2912 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 1900 and January 2100

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 1900 and January 2100 the closest approach of Neptune to Earth happens on Tue Oct 29 2041 at a distance of 28.81417197 Astronomical Units, or 4,310,538,781 kilometers:

Tue Oct 29 2041
4,310,538,781
28.814172

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

Neptune brightness

The current visual magnitude of Neptune is 7.83.

7.83
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 1900 and January 2100

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: 94.9°
Max altitude: 33.6°
Azimuth: 265.1°

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 Jul 31 23h 26m 05s -04° 51’ 02” 7.84 2.3” Aquarius
2020 Aug 01 23h 26m 02s -04° 51’ 30” 7.83 2.3” Aquarius
2020 Aug 02 23h 25m 57s -04° 52’ 00” 7.83 2.3” Aquarius
2020 Aug 03 23h 25m 53s -04° 52’ 29” 7.83 2.3” Aquarius
2020 Aug 04 23h 25m 49s -04° 52’ 59” 7.83 2.3” Aquarius
2020 Aug 05 23h 25m 44s -04° 53’ 30” 7.83 2.3” Aquarius
2020 Aug 06 23h 25m 40s -04° 54’ 01” 7.83 2.3” Aquarius
2020 Aug 07 23h 25m 35s -04° 54’ 33” 7.83 2.3” Aquarius
2020 Aug 08 23h 25m 31s -04° 55’ 05” 7.83 2.3” Aquarius
2020 Aug 09 23h 25m 26s -04° 55’ 36” 7.83 2.3” Aquarius
2020 Aug 10 23h 25m 20s -04° 56’ 09” 7.83 2.3” Aquarius
2020 Aug 11 23h 25m 15s -04° 56’ 43” 7.83 2.3” Aquarius
2020 Aug 12 23h 25m 10s -04° 57’ 15” 7.83 2.3” Aquarius
2020 Aug 13 23h 25m 05s -04° 57’ 50” 7.83 2.3” Aquarius