How to See Jupiter’s Great Red Spot (Hint: It Isn’t Red)

We all know about the Great Red Spot. This dark, blood-red patch has an imposing presence in Jupiter’s atmosphere.

Well… that’s not exactly true.

The Great Red Spot (or GRS) is a storm, and storms change over time. The color has gradually changed from a deep red to a subdued orange, and the storm has gotten smaller.

So if you’re looking for a large red spot, you may not not see it at all. It can actually be fairly challenging to see, unless you know how to find it (more on that in a minute).

One other thing: The Great Red Spot may disappear within 20 years. So you should try to see it tonight if you can!

What the Great Red Spot actually looks like

NASA photo of Jupiter's Great Red Spot showing pale orange color
Image credit: NASA/JPL-Caltech/Space Science Institute

In the photo above, you can see that the GRS is actually fairly pale – and lighter than some of the clouds around it. Keep in mind that this is a closeup photo from NASA, so you won’t see this level of detail unless you happen to own a spaceship.

Through a typical telescope, Jupiter will appear fairly small. That means the GRS will be a lot smaller and less distinct than you’re used to seeing in photos. If you adjust your expectations before you try to find it, you’ll have better luck and will be better able to appreciate it when you find it.

The right tools for the job

You’ll need a telescope to see the Great Red Spot. It’s far too small to see with the naked eye, and most binoculars aren’t powerful enough. Also, small, inexpensive telescopes may not show adequate detail, which will make it more difficult to spot the Spot.

The Great Red Spot can be seen with a Newtonian reflector (such as a Dobsonian), Schmidt-Cassegrain, Maksutov-Cassegrain, or refractor. The type of telescope you use is less important than the quality and aperture size. Larger-aperture telescopes can capture more detail and also support higher magnifications.

If you have a telescope, hopefully you have at least a couple of eyepieces. Generally, you’ll need to use an eyepiece with a lower focal length (giving a higher magnification) to see the Great Red Spot.

But depending on your telescope and atmospheric conditions, a higher magnification isn’t always better, so you may need to experiment with different eyepieces.

Knowing WHEN to look for the Great Red Spot

Step 1: Make sure you can actually see Jupiter! Depending on the time of year, Jupiter may not be visible. The best time to observe Jupiter is when it is at opposition, which means it is at its closest point to Earth. You can get this info from astronomy apps (like Star Walk) or from an astronomy magazine or news website.

Step 2: Make sure the Great Red Spot is visible. This is slightly trickier because Jupiter rotates every 10 hours or so. That means the Great Red Spot does not always face toward the Earth and isn’t always visible.

This is another way that photos can be misleading, since most photographers prefer to take photos of Jupiter’s “good side” to showcase the Red Spot. This can give people the mistaken impression that the GRS is always visible.

Luckily, there are websites that can tell you when to look for the GRS. Sky and Telescope has a Great Red Spot transit calculator. Just click “Initialize to today” and then click “Calculate”. Make sure to look at the “Local times” column (it should detect your time zone automatically).

The calculator will give you a list of upcoming transit times, which is the time when the GRS is facing directly toward the Earth. You don’t have to observe the GRS at exactly this time – any time up to one hour before or after the transit is a good time to observe it.

It’s best to observe the GRS well after sunset – the darker the sky, the better. A clear, cloudless night will also make things much easier.

What to look for

So you have your telescope set up, and you’ve used a transit calculator to know when the Great Red Spot will be visible. What now?

First, be patient. It may take a while to find, but as your eyes adapt to the dark and you familiarize yourself with Jupiter’s cloud bands, you may start to gradually see more detail.

The Great Red Spot is located in Jupiter’s southern hemisphere. Depending on your latitude and your telescope (some telescopes flip the image), the GRS may appear to be in the “top” or “bottom” hemisphere.

Although Jupiter’s atmosphere is always changing, there’s a good chance you’ll see two darker cloud bands – one in each hemisphere. The GRS is in the southern cloud band.

Because the Great Red Spot is very pale, don’t look for something red. Rather, focus on the location – if you are observing it very close to the transit time, look near the meridian (an imaginary vertical line through the center of Jupiter).

Next, look for an oval shape in or near the cloud band. The cloud band itself may actually be darker than the GRS, so the GRS itself may look like a “bite” taken out of one of the cloud bands. If you see this, look carefully, and you may begin to make out a faint yellow or tan color in the “bite”.

Other stuff you might see

You may see other shapes or details in the cloud bands. These are sometimes mistaken for the Great Red Spot. But they can also be interesting in their own way. If you’re observing with another person, try describing the details and see if they are able to see the same features.

You might sometimes see a tiny dark spot on Jupiter. This is the shadow of one of Jupiter’s many moons. If you were actually on Jupiter in that exact spot, you would be witnessing a total solar eclipse.

Once you find the Great Red Spot, spend some time really looking at it. Although it may not be red, it’s a truly unique object. It’s the largest storm in our solar system, even bigger than the Earth itself.

This storm has been raging since at least 1830, but it won’t be here forever. See it while you can!