Once you’ve found the brightest five planets – Mercury, Venus, Mars, Jupiter, and Saturn, and perhaps even taken on the challenge of Uranus, the last and furthest planet in the solar system, Neptune, awaits.

Neptune is such a tricky beast because it is the only solar system planet that is beyond naked-eye visibility from Earth. It is only slightly smaller than Uranus, but is 50% further away and never appears brighter than magnitude 7.6.

Our eyes, even under perfect conditions, can only see objects as faint as magnitude 6.5. Planet Neptune, therefore, can only be seen with an optical aid, such as binoculars or a telescope.

Thankfully, magnitude 7.6 is not incredibly faint so it’s not too tricky to spy this cold, giant planet, so long as you know when and where to look.

Finding Neptune in the Night Sky

Named for the Roman god of the sea, Neptune takes a leisurely 165 years to orbit the sun once. Its cloud tops are famed for being one of the coldest temperatures in the solar system at just 55K. In everyday language, that’s -218°C / -361°F.

Voyager 2 image of planet Neptune showing its Great Dark Spot and the Bright Smudge.
Voyager 2 image of Neptune, shows the Great Dark Spot and Bright Smudge (source)

Is Planet Neptune Visible Tonight in 2022?

Since Neptune takes so long to orbit the sun, it appears to move very slowly against the background stars. For us, this means we’ll find it in Aquarius or Pisces in 2022.

This cold world starts the year in the constellation of Aquarius, where it stays until the start of May. It can then be found in Pisces until mid-August, when it returns to Aquarius to see the year out.

  • Shines at its brightest: mid-July to mid-November
  • Magnitude Range: +7.8 to +8.0 (dimmest)
  • Visible in the evening sky: January, October – December
  • Not visible: February – May (superior conjunction is on 13 March)
  • Visible in the morning sky: June and July
  • Visible all night: August and September
  • Opposition Date – September 16, 2022

At the start of 2022, Neptune is best viewed in the evening after true darkness takes hold. This is a short window of opportunity because Neptune sets before 9pm at the end of January.

The planet moves too close to the Sun to be usefully spied from February to May, before reappearing in the predawn darkness of June’s sky. It passes directly behind the sun (superior conjunction) of 13 March.

It stays in the morning sky, gradually getting higher during hours of darkness, into July and August.

This ice giant is so distant that its visibility changes very little, even as it reaches its closest approach to us and opposition on 16 September. Its disc size and brightness increase a fraction, but not enough to be noticeable at the telescope.

A few weeks on either side of its opposition date, the planet is visible all night long. But, as 2022 progresses, Neptune becomes an evening planet visible after dusk gives way to night and setting around 4am at the beginning of November. By year’s end, Neptune sets at 11pm.

Where to Find Planet Neptune

As we said earlier, Neptune doesn’t move against the background of stars very much in a year, so it can always be found in the same small patch of sky in 2022.

The image below, from SkySafari 6, shows where it is at opposition on 14 September this year. The stars are shown to magnitude 5.0 and you can see Neptune high over the southeast horizon at 11pm. The planet is nestled between the constellations of Pisces and Aquarius.

Star chart for Neptune's 2022 opposition on 16 September
Location of Neptune on Sept 16, 2022 (click for full-screen)

However, you don’t need to look for Neptune on just this one night. Whenever Aquarius and Pisces are in the night sky, Neptune will be in approximately the same place.

To find it locate the stars Phi Aquarii and Hydor in Aquarius. These are relatively bright stars, shining at magnitude 4.2 and 3.8, respectively.

Use an imaginary line to join Hydor to Phi Aquarii, this points to the patch of sky that Neptune spends all of 2022 inside, as shown in the image below.

Detailed star chart showing where to find Neptune in 2022
Finding Neptune in 2022, click for full-screen.

For more detailed charts, use software such as SkySafari 6 or Stellarium (free), and consider joining our own Virtual Astronomy Club.

What Does Neptune Look Like Through a Telescope?

Neptune’s apparent size is a tiny 2.4 arcseconds at its closest approach to us. Even with big magnification in a decent-sized scope, the best you’ll see is a recognizable disc (rather than a pinprick of light, like a star) with a bluish hue.

Use even a small telescope at a magnification of 100x or to see color which is caused by methane in Neptune’s atmosphere absorbing red light and reflecting blue.

Swap up your magnification to 200x and your telescope will reveal that this is not a point of light like a star, but a disc. This is your first confirmation that you are looking at a planet.  

Sadly, there are no surface features apparent with small telescopes, but just seeing the planet is a bigger achievement than many backyard astronomers can claim.

Can You Spot Neptune’s Moons?

Neptune has a moon called Triton, which you have probably heard of. Triton is slightly odd because it is the only moon in the solar system which orbits against the direction of the planet’s spin.

Triton is also a big satellite, the seventh-largest in the solar system. However, it is such a distance from us that it shines below magnitude 13 and is effectively out of reach of average amateur telescopes.

There are 13 other moons known around Neptune, but they are all considerably smaller than Triton.

More on Neptune…

If you have a desire to learn more about Neptune, check out our article Neptune: All you need to know for fascinating information about the planet.

  • Sharmila Kuthunur

    Sharmila Kuthunur is a freelance science writer based in India. She has been a bibliophile for as long as she remembers and her love for reading introduced her to Carl Sagan’s Pale Blue Dot. She has been hooked to astronomy ever since. In addition to writing for Love the Night Sky, she also contributes feature articles to Astronomy Magazine, where her work allows her to bombard scientists with unlimited questions. She also loves putting thoughts into words. On her blog, Fuel Your Curiosity she narrates astronomical phenomena as stories to make science fun to read.