How To See Neptune Through A Telescope

How To Find Neptune In The Night Sky?

Neptune is so far away from the Sun that it rotates on its axis once every 16 hours and orbits the Sun once every 165 years. This means that Neptune hardly changes its position and it can always be found in the same small patch of sky.

Since the planet moves so slowly, you can find Neptune within the Aquarius constellation throughout the year 2021.

Because it moves so slowly, Neptune will spend the entirety of 2021 within the Aquarius constellation. Towards the end of the year, the planet will get very close to Pisces, but it will still remain in relatively the same place. 

As the year progresses, Neptune will get very close to Pisces, but it will still remain in almost the same place.

So whenever Aquarius and Pisces are in the night sky, Neptune will be in approximately the same place.

The best way to find the exact location of Neptune on any day or night of the year is to use astronomy phone apps such as SkySafari 6, Stellarium, SkyView Lite, or Night Sky Lite.

All you have to do is open the app on your phone and move your arm across the sky. The app will show you every sky object that’s there in the sky at that time. To find something specific, such as planet Neptune, use the search feature of these apps and you will have all the necessary information about the celestial object on your screen within seconds.

What Does Neptune Look Like Through a Telescope?

When you look at Neptune through a telescope it appears blue because huge quantities of methane gas in its atmosphere absorb all the red light from the sun and reflect the leftover blue light.

As I said before, the planet Neptune is quite difficult to observe, even with good magnification in a large amateur telescope, Neptune will look like a regular star with a bluish hue. This bluish hue will confirm that you’re looking at the planet and not at any random star.

Once you have found Neptune through your telescope, I highly recommend increasing the magnification. That is when Neptune will come into focus as a tiny blue disc rather than a pinprick of light, like a star.

There are two major surface features on Neptune called “Great Dark Spot” and the “Bright Smudge”. Both of these are parts of a storm on Neptune’s surface that is the size of the planet Earth. 

Although these surface features are as big as our planet Earth, you cannot see them from here even with a large telescope because Neptune is so far away.

Although you won’t be able to get a great view of the surface or the storms of the planet, just being able to see the flat blue disc which lies 2.8 billion miles away is an achievement in itself.

Best Telescope To See Neptune

You can see Neptune to an extent with any intermediate telescope. However, there are a few characteristics that make a telescope perfect for observing Neptune. 

As I mentioned at the beginning of this article, it’s best to observe Neptune with a telescope that has a long focal length. A telescope with a long focal length will allow you to focus on a small part of the sky where Neptune is visible. 

Although you won’t be able to see any surface features of Neptune, to distinguish it from the surrounding stars you would need a telescope with a magnification power of somewhere between 150x-200x. 

With such magnification, the planet Neptune will appear as a flat disc with a blueish hue which is very different from the stars around it. This is the best way to distinguish Neptune from the stars while observing it through a telescope.

Below are a few telescopes that I highly recommend that can help you see Neptune and other exclusive heavenly bodies.

• Celestron – NexStar 8SE – Computerized Telescope
• Orion 9738 SkyView Pro 8-Inch Reflector Telescope
• Sky-Watcher Flextube 200 Dobsonian 8-inch Collapsible
• Celestron CPC 1100 StarBright XLT GPS Schmidt-Cassegrain
• Celestron – NexStar 127SLT Computerized Telescope

Can You See Neptune’s Moons Through A Telescope

Neptune has 14 moons, the latest discovered in 2013. Each of the moons is named for a mythological Greek water deity. Moving from closest to Neptune to furthest out, their names are Naiad, Thalassa, Despina, Galatea, Larissa, Proteus, Triton, Nereid, Halimede, Sao, Laomedeia, Psamathe, and Neso.

The first moon to be discovered was Triton, which is also the largest one. Although Triton is the largest moon of Neptune, it is also very dim which makes it impossible to be seen without a very powerful telescope meant for scientific research. 

Useful Tips To Get The Best View of Neptune

Since Neptune is very far from Earth and very dim in the sky follow these tips to get the best views through your telescope.

1. Use a telescope with a large aperture with a long focal length.
2. Refer to the star charts or any of the astronomy apps to know the exact location of Neptune in the sky.
3. Use a GoTo telescope as it makes it easy to locate and view any of the sky objects and not just Neptune.
4. Remember that Neptune will appear as a small bluish disc in a sea of background stars.

Neptune At Opposition In 2021

In 2021, Neptune reaches opposition on September 14 at about 9 UTC. That’s when Earth is flying between the sun and Neptune, placing this outer world 180 degrees from the sun – opposite the sun – in our sky. Opposition marks the middle of the best time of year to observe an outer planet. At opposition, the planet rises in the east as the sun sets in the west and is visible throughout the night.

Neptune’s 2021 opposition takes place in front of the constellation Aquarius the Water Bearer.

In 2021, Earth and Neptune come closest for the year the day before opposition, on September 13. If Earth and Neptune both orbited the sun in perfect circles and on the same plane, then Neptune would be closest to Earth at opposition. But, in 2021, Earth comes closest to Neptune about 20 hours before opposition. By the time opposition rolls around, Earth is a bit closer to the sun (and, therefore, farther from Neptune).