Observing the majestic planet Jupiter through the lenses of a telescope is an awesome experience that can transmute you from an ordinary stargazer into a fully-fledged amateur astronomer. Viewing planets through a telescope and getting to see the almost live images of the celestial bodies kilometers away is nothing short of awe-inspiring.
In this article, I will be telling you how best to see Jupiter with a telescope.
I will also discuss how to find Jupiter in the night sky and factors to consider when observing Jupiter through a telescope. So stick with me through the end and get to learn these and more Jupiter-related topics. Let’s get started.
Jupiter: The Third Brightest Object in the Sky
Before we go deeper into viewing Jupiter with a telescope, we first need to understand what Jupiter is. This giant planet is mostly made of gases helium and hydrogen.
The planet is 11 times wider than our planet Earth (that’s about 139900 kilometers in diameter). It is 318 times bigger than Earth.
Jupiter has a massive hot and icy core at its center, but unlike Earth, the planet does not have a surface. Instead, it has layers that blend into each other smoothly.
How to Find Jupiter in the Night Sky
Jupiter is among the brightest planets in the sky, making it easy to spot and track when it is up. It is worth noting that you are not always going to see Jupiter up in the sky because the conditions of the night sky keep changing over the day and throughout the year, so the planet is not going to be up every evening.
In my experience tracking the planet, sometimes I see it in the early morning, sometimes early in the night, and other times it is very difficult or impossible to locate. However, when it is up, Jupiter appears as a bright yellow-white or white star. It doesn’t twinkle, and it often appears before the stars are up.
However, there are better and easier ways to find Jupiter in the sky. If you are good at identifying constellations, you just need to figure out the opposition of Jupiter in which constellation and you will easily locate it.
For instance, on November 2nd 2023, the planet’s opposition will place it at 3.9 AU (583431696 kilometers) opposite to the Sun in the constellation Aries. During this time, Jupiter will be at its highest point in the sky at midnight.
It will also be visible for most part of the night. You can easily find a chart of the constellations the planet will be in during different oppositions online.
Another way to locate Jupiter is by using various astronomy software and mobile applications. Software like Stellarium and Sky Safari will give you detailed information on where to look for Jupiter (and other planets).
There are also plenty of mobile applications, such as Star Walk 2 for both Android and iPhone, that you can use to locate Jupiter. When you know the planet is up, you now need to view it.
How to See Jupiter Without Telescope
I mentioned earlier that Jupiter is a big bright planet that you can easily observe without a telescope. If you already know where the planet is, say, by using mobile software, you can start finding it with your naked eye.
Most astronomy applications and software will give you a sky plan. Use that plan to try and locate the planet.
For instance, the software may give you the altitude of Jupiter as 12.5 degrees above, say, the Southeast horizon. Now, the horizon itself will be at 0 degrees. Directly above the horizon will be at 90 degrees, and midway between the horizon and directly overhead is 45 degrees.
You can, therefore, roughly locate the planet. It will be the brightest spot you will see.
You can also use good-quality binoculars to see Jupiter. Binoculars with 7x to 20x magnification will do a good job.
Once you find the location of the planet using your application, point your binoculars towards the direction. If you see a bright point of light, that’s Jupiter.
A more powerful pair of binoculars will show Jupiter as a slightly yellowish spot that doesn’t twinkle. Now, pay attention to either side of the planet. You should see a line of four or three tiny starts. Those are satellites (moons) of Jupiter. Each of them is about the size of our Moon.
How to See Jupiter with a Telescope
Now, let’s look at how you can see Jupiter with a telescope. I am going to discuss how to view the planet with a small telescope, a moderately powerful one, and then a more powerful telescope.
Viewing Jupiter with a Small Telescope
Here, I am assuming the conditions are good for stargazing, and you have a small telescope of magnification between 20X and 50X. Now, all you need to do is set up your small telescope and set the finderscope correctly. Find the location of Jupiter using the methods discussed in the section above.
When you have the location ready, center the finderscope on the brightest spot you have identified. Look through the eyepiece to find out whether or not you have Jupiter in view.
Note that there may be many stars around the planet, but it is easy to locate it because it is disc-shaped. Stars appear as small pinpricks of light.
You need to further confirm if you are really observing Jupiter. How to do this? Closely check either side of the planet.
You should see four or three starts in a straight line with the planet. Sometimes, they can be on one side, but in most cases, they are on either side of Jupiter. If they are there, then you are definitely looking at Jupiter because those are its satellites.
If you have a telescope with about 50X magnification, you may see 1-2 dark bands or stripes running across the face of the bright disc. This is another huge giveaway that you actually have Jupiter in your view.
Viewing Jupiter with a Medium and Large Telescope
By medium, I mean any telescope with 100X TO 200X magnification, and by large, I mean anything with 200X to 400X magnification.
You also need to follow the steps outlined above; that’s finding the planet and setting up your telescope and its finderscope. With a medium telescope, you begin to see the really subtle details of the planet. You should see the two dark stripes running across the bright disc.
The Galilean moons should also be visible with a medium telescope. If you are more careful, you may spot a shadow on Jupiter.
This happens when a satellite passes past in front of the planet. The shadow you see is often that of Callisto or Ganymede (two of Jupiter’s satellites), as they are larger than the other two satellites.
With a larger 200X telescope, you can see more detail on the planet. For instance, you may be able to see more than 2-3 cloud belts and multiple large dark-brown barges.
At 300X magnification, you can see Jupiter clearly and sharply. You are also going to see multiple cloud bands, brown barges, structures on the Great Red Spot, as well as subtle festoons.
Occasionally, you may also see white ovals against the planet’s equatorial belts as well as subtle temperate belts. When the satellites are transitioning, you can see a satellite(s) as a tiny spot.
However, the satellites are low-contrast and quite difficult to clearly observe compared to the shadows they cast on Jupiter.
If you have a very large telescope in the range of 12 inches+, you will begin to see subtle features of Jupiter’s satellites. For example, you can see the albedo features of Ganymede because of its massive size.
What to Target When Viewing Jupiter with a Telescope
So now you know how to see Jupiter with a telescope, but what should you be targeting to have the best viewing experience?
I have three targets in mind. The first one should be Jupiter’s largest moons, called the Galilean moons. These moons are easy to spot, even with a small telescope or powerful binoculars.
As I have explained in previous sections, the moons appear as small stars (usually 3 or 4) in a straight line with the planet.
These satellites transit. So, as they orbit, you may see all of them behind or in front of the planet. However, in most cases, you will see them on either side of the planet.
The second thing you want to pay attention to is the major bands and zones. Even with smaller telescopes, you should see the bands or stripes across the planet. If you have a larger telescope, you will see more subtle details, and the stripes should be thinner.
Lastly, you should target the Great Red Spot. You will only be able to see this spot with its features and structures with a magnification of about 300X or more.
How to See Jupiter with a Telescope: Factors to Consider
Here are some of the most critical factors you want to consider when viewing Jupiter with a Telescope:
The Effect of the Atmosphere
When Jupiter is lower on the horizon, the light coming from it travels a longer distance in the atmosphere. When it is higher up, the light from it has a shorter distance to cover. This difference may affect the quality of the images you get.
You, therefore, want to view the planet when it is ideally positioned. Use mobile applications and astronomy software to determine the best possible time to view the planet.
Light pollution is a major issue of concern for stargazers. Light pollution causes an unwanted glow in the atmosphere that may distract your viewing. Also, light from street lights reduces the contrast between the target planet and the sky’s dark background.
However, since Jupiter is very bright, you can still see it with minimal light pollution, but it is always a good idea to choose locations with the least amount of light pollution.
The “Seeing” condition is often used by stargazers to describe the condition of the atmosphere when you are in an observing session. Note that the atmosphere is made up of various gases that keep moving and swirling around. They can affect the quality of your viewing sessions.
You may, for instance, notice that the planet is blurry even when you have everything set perfectly. This will be more likely be a result of poor seeing conditions.
This is another huge factor that may affect your Jupiter viewing sessions. You want to choose your viewing spot carefully and avoid areas that may have a lot of air turbulence.
For instance, avoid setting up your telescope on a concrete surface. Why? The concrete absorbs the sun’s heat during the day, and at night, it will still produce the heat back towards the atmosphere, stirring the air above.
You should also avoid setting up your viewing spot directly above your house as there will still be heat coming from the chimney or off the roof that will cause air turbulence distorting the images you get.
Temperature and Dark Adaptation
The equipment you use, whether it is a reflecting or refracting telescope, is going to be affected by the temperature outside. The telescope has various metal parts and lenses that may expand or contact depending on the outside temperature.
It is, therefore, advisable to leave your equipment outside for about 20-30 minutes before viewing so that all the parts adjust accordingly.
Your eyes also need to adapt to the darkness outside. You don’t want to get out of your abundantly-lit house and go straight to the eyepiece. Go out with a cup of coffee and sit by your equipment as you wait for your equipment to adjust to the temperature outside.
Viewing Jupiter with a telescope is one of the best stargazing experiences you will get as an amateur astronomer. The star is bright and has a lot of features that are just awe-striking.
As we have discussed, you can see the planet with your naked eyes, binoculars, or even a small telescope. However, the experience gets better with larger telescopes. Follow the tips provided above and enjoy your Jupiter viewing sessions.