Observing Every Planets Through Your Telescope - An introduction

Last Updated: 15th April 2019

Observing the planets of our solar system through a telescope is not as difficult as you may think. Many beginners imagine that astronomy is a complex science that only those with advanced degrees in physics or mathematics can practice. With a little training and patience, it is possible to observe many wonders such as the large cloudy bands of Jupiter, the gigantic rings of Saturn, but also the Moon, our companion in space.

Can you see planets with a home telescope?

It is definitely possible to observe the planets with your home telescope. Depending which celestial body you chose to look at, even the more modest equipment can offer a good viewing. The most important thing is to try to observe them without atmospheric turbulence because the planets usually require a higher magnification. The slightest turbulence can blur the image and the finer details are no longer perceptible.

Even with the naked eye, it is possible to spot the planets in the night sky. They usually look a little bit different than stars and they do not twinkle as much. Even if you are located in a city with light pollution, you should be able to easily find them.

Our readers frequently ask us if there is one optical instrument that is best for planetary observation. The truth is all models, refractors or reflectors, can allow you to achieve very good planetary observations.

Observing the inferior planets through a telescope

The inner planets are a little more difficult to observe because they orbit very closely to the sun. From our point of view on Earth, they are never too far away from our home star. They follow it through the Ecliptic (an imaginary line in the sky that marks the annual path of the sun). For this reason, it is much easier to observe those planets during their “greatest elongation”, which is the moment where they are the furthest away from the sun. 

Bonus Target: The Moon.

The Moon is in synchronous rotation with Earth meaning the same side is always facing the Earth.

Find out how you can observe the Moon through a telescope.

picture of the moon
  • Brightness: -4 (min) / -12 (max)

This planet is among the most difficult to observe as it does not deviate much from the Sun and is often low on the horizon. Its greater elongation is only 28°

Check out how you can see Mercury through a telescope.

picture of planet Mercury
  • Next Favorable Position: 20 Oct 2019
  • Brightness: 5.14 (min) / -2.42 (max)

Depending on the time of the year, Venus can be observed either early morning or early evening. It is the brightest planets due to close it orbits the sun. This planet can actually be observed during the day with a telescope, granted you are being extra prudent that your field of vision does not go too close to the sun. Venus display phases, just like the moon, and many amateur astronomer try to capture image of every phases this planet go through. 

picture of planet Venus
  • Next Favorable Position: 24 March 2020
  • Brightness: -3.82 (min) / -4.73 (max)

Observing the superior planets through a telescope

The outer planets (particularly Saturn) are often the reason why people fall in love with stargazing and buy their first amateur telescope. The closest outer planets can be seen even in modest optical instruments

Mars is bright enough to always be visible to the naked eye. It generally looks like a star with a reddish hue, however, it does not twinkle as much as stars can do. Even with modest telescope, you can make out quite a lot of the planet’s surface features. Mars is at its closest position to Earth every two years and for about two months: the ideal moment to take your telescope outside and observe the red planet. With enough practice, you might even be able to see the polar caps!

picture of planet mars
  • Next Favorable Position: 14 October 2020
  • Brightness: 1.74 (min) / -2.72 (max)

This planet is one of the easiest telescopic target to observe and does not require an expensive or large optical instrument. Throughout the entire year, Jupiter is usually visible during a big part of the night. Every 13 months, this planet enters a new constellation in the sky, which makes it relatively easy to track for long period of time. Even in small telescopes, let’s say 4inch aperture, Jupiter will look majestic and you should even be able to make out some of the 4 Galileans moons. With a telescope of 8inch or more, you should comfortably see the great red spot and enjoy the different colours made out by the belts and zones that constitues the planet’s surface.

picture of planet Jupiter
  • Next Favorable Position: 14 July 2020
  • Brightness: -1.74 (min) / -2.62 (max)

The ringed planet is the most impressive telescopic target to observe and is often the reason why so many people fall in love with stargazing. Saturn is the easiest planet to admire through a telescope.  With a 200mm telescope, you can make out so many details, including cloud layers. Depending on your instrument, you might even be able to spot a few Saturnian moons. Titan and Rhea particularly, as they orbit the planet rather rapidly (16 days and 4,5 days respectively.) 

Saturn is ideal for anyone beginning in stargazing and owns an entry-level telescope for practice.

a picture of planet Saturn
  • Next Favorable Position: 20 July 2020
  • Brightness: 1.46 (min) / -0.92 (max)

Uranus is far, very far. To see it through a telescope, you need advanced equipment and be under a perfectly black sky. You will also have to know precisely its location and the stars around it, as it can be very easy to confuse the planet with background stars. With binoculars, the problem remain the same. It would be ideal to have a telescope of 80 mm and a magnification of at least 200 times. Even with the best viewing conditions and a decent telescope, you would only be able to make out a fait dot with a blueish hue. 

While it’s not the most impressive planet to observe through a telescope, we still find it rather amazing that this distant celestial body it can be seen from a backyard.

a picture of planet Uranus
  • Next Favorable Position: 28 October 2019
  • Brightness: 5.89 (min) / 5.67 (max)

The gas giant is very far from the Sun and requires a high magnification (200 to 300) to be seen. A large telescope may reveal a very small disc of a bluish colour due to the methane present in the upper atmosphere.

Find out how you can observe Neptune through a telescope.

a picture of planet Neptune
  • Next Favorable Position: 10 September 2019
  • Brightness: 7.96 (min) / 7.82 (max)

The Dwarf planet is extremely far from us. Seeing Pluto requires a telescope with at least 8 inches (200mm) aperture at a minimum. Even then, Pluto will resemble a tiny star. Nonetheless, many amateur astronomers are proud to observe this planet as it is truly a challenging target.

Discover how you can observe Pluto through a telescope.

a picture of planet Pluto
  • Next Favorable Position: 16 July 2020
  • Brightness: 14

What do planets look like through a telescope?

It is important to understand that what you will see while looking at the planets through a telescope will be very different from the numerous images you may have seen online. These images are usually digitally processed and enhanced with a software.

In reality, you will see live images, often through thick layers of atmosphere that can make the image slightly blurry. Think of it this way: if you were to look at an object through water, the further away the object is, the harder it would be to see it clearly. Now imagine that the water started flowing and move back and forth: observing the object would be even harder. This is the same principle with celestial bodies in the sky, but the water from our example would be the atmosphere. The quality of your viewing will also depend on your optical instrument. A larger telescope offering a higher magnification will always perform better than the entry-level telescopes.

Below are some examples of what the planets might look like through a telescope.

Pro-Tip: Before investing in a telescope, we recommend finding an astronomy club near where you live and participate in star parties. You will be able to try different optical instruments and learn more information about them from a fellow amateur astronomer. This will definitely help you make a more informed decision, as some telescope are more specialised for planetary observation and some are better for deep sky object like galaxies.

The easiest way to spot the planets in the sky

There are many ways to spot the planets. One of the easiest solution is to use a free software called “Stellarium”. It’s a sort of digital planetarium that allows you to simulate the sky in real time depending on your location, including the planets position, the constellations, as well as some information about the brightest stars.

Once  you’ve set up your location, you can check the position of the stars and planets that you want to observe today or at a future date: you can speed up time or even go back in time to see how the sky looked like a few weeks ago. This software is very handy for anyone wanting to plan their stargazing session in advance!

You can download and learn how to use it here: https://stellarium.org/

Observing the planets of our solar system through a telescope is not as difficult as you may think.