Facts About Jupiter: The Biggest Planet in the Solar System
See Jupiter at its best in January 2026! On January 10, the planet will reach opposition and shine at its brightest throughout the night. Locate Jupiter in the sky with the Sky Tonight app and keep reading this article to learn more about the planet.
Contents
- Jupiter Planet Facts
- What does Jupiter look like?
- How big is Jupiter?
- Jupiter's orbit and rotation
- How far away is Jupiter?
- What does Jupiter look like?
- Jupiter's moons
- Does Jupiter have rings?
- Missions to Jupiter
- When and where is Jupiter visible in 2026?
- F.A.Q.
- Did you know?
- All about Jupiter: Bottom line
Jupiter Planet Facts
- Planet type: gas giant
- Radius: 69,911 km (43,441 mi)
- Mass: 1.8982×10^27 kg
- Aphelion: 817 mln km (508 mln mi)
- Perihelion: 741 mln km (460 mln mi)
- Average distance from the Earth: 778 mln km (484 mln mi)
- Surface temperature: −145 ℃ (−234 °F)
- Solar day length: 9 h 55 m 33 s
- Sidereal day length: 9 h 55 m 30 s
- Year length: 11.8618 Earth years
- Age: 4.603 billion years
- Named after: Roman god of the sky and thunder
What does Jupiter look like?
Jupiter is a giant ball of gas wrapped in swirling cloud bands. It doesn’t have a solid surface, and scientists still aren’t sure whether it has a solid core deep inside or if it's just a super-hot, dense mixture all the way through. Jupiter also has rings, but they’re faint and difficult to see from Earth.
In the sky, to the naked eye, Jupiter appears as a very bright dot, and a small telescope will show it as a pale white or cream-color planet. Want to observe it yourself? Check out our guide with tips for spotting this majestic planet.
How big is Jupiter?
Jupiter is considered the giant or the Jovian planet, together with Saturn, Uranus, and Neptune. When ancient astronomers named Jupiter after the Roman ruler of all gods, they had no idea about its enormous size, surpassing other planets. Yet, they came up with a very fitting name.
Is Jupiter the biggest planet in the Solar System?
With a radius of 69,911 km (43,441 mi), Jupiter is the biggest planet in the Solar System. In comparison, the second-biggest planet, Saturn, has a radius of 58,232 km (36,184 mi). Jupiter is also the most massive planet — it’s more than twice as massive as all the other planets combined.
Jupiter size compared to Earth
Are you struggling to imagine something as huge as Jupiter? Let’s say that it would take more than 1,300 Earths to build a single Jupiter. If the gas giant were the size of a basketball, the Earth would be the size of a grape.
Jupiter's orbit and rotation
Each planet takes a certain amount of time to complete one orbit around the Sun and one rotation around its axis. As we live on the Earth, we take the local days (24 hours) and years (365.25 days) as a standard. Let's see how different from our planet Jupiter is.
How long is a day on Jupiter?
Despite being the largest planet, Jupiter is also the fastest-spinning planet in the Solar System; therefore, it has the shortest days. One day on Jupiter lasts slightly less than 10 hours — the exact time varies from 9 hours and 56 minutes around the poles to 9 hours and 50 minutes close to the equator. The reason behind this difference is that Jupiter is a gas planet and doesn’t rotate as a solid sphere. Instead, its equator rotates slightly faster than the polar regions, which leads to the distinction in the day length in different areas.
How long is a year on Jupiter?
One Jovian year takes 11.8618 Earth years or 4,332.59 Earth days – this is how long it takes the planet to orbit the Sun. In comparison, the second-largest planet Saturn has an orbital period of around 29 Earth years, and the smallest planet Mercury revolves around the Sun every 88 Earth days.
How far away is Jupiter?
Jupiter is the fifth planet from the Sun: Mercury, Venus, Earth, and Mars lie in between them. There is also the asteroid belt located roughly midway between Mars and Jupiter’s orbits.
How far is Jupiter from the Sun?
The gas giant is 5.2 AU from the Sun or 778 mln km (484 mln mi) away. In comparison, Mercury, the closest planet to the Sun, is 0.4 AU or roughly 58 mln km away (35 mln mi) from our star. Quick reminder: one astronomical unit (AU) is the distance between the Sun and the Earth.
How far is Jupiter from the Earth?
The distance between planets is constantly changing because they are moving along their orbits. Jupiter is only 588 mln km (365 mln mi) away when it’s closest to our planet and 968 mln km (601 mln mi) at its farthest.
How long would it take to get to Jupiter?
If you want to make a simple flyby, it will take about 550-650 days, as happened with the Voyager spacecraft: Voyager 1 took only 546 days, and Voyager 2 took 688 days. However, if you’re actually planning to go into Jupiter’s orbit, you’ll need to be going slowly enough when you reach the planet. For example, NASA’s Galileo spacecraft flight duration was 2,242 days before it finally arrived at Jupiter.
What does Jupiter look like?
Jupiter doesn’t have a solid surface; its atmosphere just gets denser the farther down you go, transitioning into a liquid layer surrounding a small core. Simply, it means that the atmosphere of Jupiter makes up almost the entire planet. Jupiter (and its atmosphere) consists of about 90 % hydrogen and 10 % helium — which is very similar to the Sun’s composition.
Jupiter’s formation
Like other planets in the Solar System, Jupiter formed about 4.5 billion years ago, when gravity pulled gas and dust together to create the gas giant. The planet took most of the mass left over after the formation of the Sun and became more than twice the combined material of the other bodies in the Solar System. About 4 billion years ago, Jupiter settled into its current position as the fifth planet from the Sun.
Jupiter's structure
We still don’t know for sure what Jupiter’s core looks like. It might consist of solid materials or be a thick, boiling, dense soup. What we know is that the core is surrounded by a layer of liquid metallic hydrogen that extends out to 90% of the planet’s diameter.
Surface of Jupiter
This gas giant doesn’t have a hard surface like we do on Earth. The planet is mostly swirling gases and liquids. A spacecraft can’t land on it or fly through the planet due to the extreme pressures and temperatures that will crush, melt, and vaporize it.
What is the Great Red Spot on Jupiter?
The Great Red Spot is a giant storm (about twice as wide as the Earth) located in Jupiter’s Southern Hemisphere. It consists of crimson-colored clouds that spin counterclockwise at a speed that exceeds any storm’s speed on the Earth.
This storm was first observed in 1878; however, Gian Domenico Cassini in 1665 mentioned “Permanent Storm,” which is believed to be the Great Red Spot. Such a long-lasting storm can be explained by the absence of a solid surface on Jupiter. On Earth, hurricanes disintegrate when they reach solid ground, but the Red Spot simply doesn’t have land to collide with.
How to see the Great Red Spot
To see Jupiter’s Great Red Spot (GRS), you’ll need at least a 6-inch telescope for a reliable view and the right timing. Since Jupiter rotates rapidly, the Great Red Spot periodically rotates into and out of our view. To find out when it’s visible from your location, use the astronomical calendar in the Sky Tonight app.
- Open Sky Tonight.
- Search for “Jupiter” and open its object card.
- Go to the Events tab.
- There you’ll see the times when the Great Red Spot is visible from your location.
Before planning the observation, make sure Jupiter is visible in the sky. The planet is best observed around opposition (the next one takes place on January 10, 2026) and is not visible around solar conjunction.
To quickly check whether Jupiter is visible tonight, tap the telescope icon at the bottom of the app screen and see if Jupiter appears in the list.
Is the Great Red Spot shrinking?
The Great Red Spot on Jupiter has been shrinking over time — from a length of about 39,000 km (24,200 miles) in 1879 to about 14,000 km (8,700 miles) in 2024. The spot is also becoming more rounded. Astronomers suppose the shrinking may be caused by a change in the Great Red Spot’s “diet”. The growth and stability of this gigantic storm depend on devouring smaller storms — and lately, there has been a decline in such storms near the Great Red Spot.
Jupiter's moons
Jupiter and its numerous satellites resemble a miniature Solar System and present a scientific interest for astronomers around the world.
How many moons does Jupiter have?
Jupiter has 95 moons. Most of them are small — about 60 satellites are less than 10 km (6.2 mi) in diameter. As of 2026, Jupiter is losing to Saturn in terms of the number of satellites; according to NASA, the ringed planet has 274 moons.
What are the names of Jupiter's 4 largest moons?
Jupiter’s four largest moons are Io, Europa, Ganymede, and Callisto. They’re called the Galilean moons after their discoverer and are as remarkable as Jupiter itself.
Ganymede is bigger than Mercury and is known as the largest natural satellite in the Solar System. It even has its own magnetic field and can have a subsurface ocean.
Europa, which is about 90% the size of the Earth's Moon, has a very high potential to be habitable — there is evidence of a vast ocean just beneath its icy surface. It’s thought to have twice as much water as the Earth! The Europa Clipper spacecraft is now on its way to Europa to confirm whether it has conditions suitable for life.
Io, that’s slightly larger than our Moon, is the most volcanically active body in the Solar System. It has over 400 active volcanoes on its surface!
Callisto, which is about the same size as Mercury, is the third-largest moon in our Solar System. Its surface is the most heavily cratered of any known object in the Solar System. Like Ganymede and Europa, it can have an underground ocean of liquid water beneath its icy crust.
How to see Jupiter’s Galilean moons?
To see Jupiter’s Galilean moons, simply point your telescope at Jupiter. The four largest moons — Io, Europa, Ganymede, and Callisto — are easy to spot even with a small telescope. A decent pair of binoculars can also show them as tiny points of light close to the planet, though a telescope will show them more clearly.
If you want to tell the moons apart and check where each one is at the moment you’re observing, use the Sky Tonight app. Open the app, type a moon’s name (for example, “Io”) in the search bar, open the result, and tap the target icon — the app will show the moon’s current position.
The moons don’t always appear as dots beside Jupiter. Depending on their positions, you may also notice:
- Transit: a bright dot crossing Jupiter’s disk.
- Shadow transit: a small dark spot moving across Jupiter — the moon’s shadow on Jupiter’s cloud tops.
- Occultation: a moon passing behind Jupiter, so it disappears for some time from your point of view.
To find out when these events will happen, search for a Galilean moon in Sky Tonight (for example, “Ganymede”), open its object card, and check the Events tab. There you’ll see when the moon passes in front of Jupiter, behind it, or casts a shadow, as seen from Earth.
The most notable events are double transits, when two Galilean moons (or their shadows) cross Jupiter at the same time. Find them in the Calendar window by tapping the Calendar icon at the bottom of the main screen. There, look for the planet icon with horizontal bands and a small dot on its disk.
Does Jupiter have rings?
The Jovian ring system was the third ring system discovered in the Solar System, after those of Saturn and Uranus. Jupiter’s rings are faint and mostly consist of dust; they’re likely leftovers from the meteor bombardment of Jovian moons.
How many rings does Jupiter have?
Jupiter has four rings: a faint halo ring (the closest to the planet), a relatively bright but very thin main ring, and two wide and thick gossamer rings — the Amalthea and the Thebe. The last two are named after the moons of whose material they consist. You can take a closer look at the Jovian ring system mosaic to understand the Jovian ring system better.
Are Jupiter's rings visible?
You surely won’t see the Jupiter rings with the naked eye since they’re too faint and tenuous. For ground-based observation, the largest telescopes available are required. Even from space, they’re visible only when viewed from behind Jupiter and are lit by the Sun or directly viewed in the infrared.
Missions to Jupiter
Past missions to Jupiter
Since 1973, numerous spacecraft have visited Jupiter. Here, we’ll mention the most iconic missions.
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The first one was NASA’s Pioneer 10, which provided hundreds of Jupiter’s photos and collected some measurements. The Pioneer 11 in 1974 got three times closer to the planet than its predecessor.
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In 1979, the famous Voyager spacecraft discovered the Jovian ring system and took thousands of pictures of clouds and storms on the planet. Those pictures also showed that the mysterious Great Red Spot is a gigantic storm. Moreover, Voyager 1 and 2 discovered dozens of volcanoes on Jupiter’s moon Io — the first found active volcanoes on another space object.
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NASA’s Galileo probe became the first spacecraft to enter Jupiter’s orbit; it arrived on the planet in 1995. The Galileo mission, among many other things, examined Jupiter’s atmosphere and immense magnetic field and closely studied the Galilean moons. Several years later, in 2000, the Cassini spacecraft that was heading to Saturn took some of the best photos we have of Jupiter.
Current and upcoming missions to Jupiter
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NASA’s Juno spacecraft entered a polar orbit of Jupiter in 2016. Juno is studying Jupiter’s atmosphere and interior structure to determine the composition of the planet and to help scientists learn how giant planets were formed. The mission will continue until the end of Juno’s operational life.
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NASA’s Europa Clipper probe was launched in October 2024 and will arrive at Jupiter’s moon Europa in April 2030. The spacecraft will perform a series of fly-bys of Europa and determine whether its underground ocean is habitable. Watch our short video to learn more about Europa Clipper.
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ESA’s Juice spacecraft (Jupiter Icy Moons Explorer) will enter Jupiter’s orbit in 2031. It will explore the gas giant and three of its moons: Europa, Callisto, and Ganymede. Like Europa Clipper, Juice will attempt to determine whether Jupiter’s moons have conditions suitable for extraterrestrial life.
When and where is Jupiter visible in 2026?
In early 2026, Jupiter will be at its biggest and brightest. As it approaches opposition on January 10, the planet will reach an apparent magnitude of about -2.7 and an apparent size of about 46–47 arcseconds.
After opposition, Jupiter will set a little earlier each day. In January and February, it will be an all-night object, staying up from dusk till dawn. Around February 28, Jupiter will be part of a six-planet evening alignment. By mid-June, it will be setting around midnight. At the same time, Jupiter will appear very close to Venus, creating a couple of interesting alignments. On June 21–22, near the June solstice, Jupiter will move from Gemini into Cancer.
On July 29, Jupiter will reach solar conjunction and become lost in the Sun’s glare, making it essentially unobservable. When it returns in August, it will reappear in the morning sky. It will also take part in a large planetary alignment on August 12, — a date highlighted as one of the best stargazing opportunities of the year (see our dedicated article for details). On September 24, Jupiter will enter Leo, where it will remain through the end of 2026. On December 13, it will start moving "backward" in the sky.
Upcoming events
January 10, 2026: Jupiter opposition
Jupiter will be in opposition to the Sun on January 10, 2026, at 08:34 GMT. The planet will shine brilliantly at a magnitude of -2.7. You’ll find Jupiter in the constellation Gemini, where it will rise in the east at sunset and remain visible all night, reaching its highest point around midnight local time.
Even without optical aid, Jupiter will be a dazzling sight. Through binoculars or a small telescope, you’ll be able to spot its four largest moons — Io, Europa, Ganymede, and Callisto — which appear as tiny points of light lined up near the planet. A telescope will also reveal Jupiter’s striped cloud bands.
At opposition, Jupiter will come closest to Earth for 2026 — at a distance of about 4.23 astronomical units. Its disk will appear especially large, measuring 45.6 arcseconds across, offering excellent conditions for detailed observation.
January 31: Moon near Jupiter
- Conjunction time: 02:30 GMT
- Conjunction distance: 3°50'
- Close approach time: 03:38 GMT
- Close approach distance: 3°47'
On January 31, the 95%-illuminated Moon will be close to Jupiter (mag -2.6) in the sky. Observe them with the naked eye or through a pair of binoculars in the constellation Gemini. Both objects will be high in the sky already at sunset and will be visible almost until dawn.
Six planets alignment on February 28, 2026
Look for a large planetary alignment around February 28, 2026! In the evening, about an hour after sunset, six planets — Jupiter, Uranus, Saturn, Neptune, Venus, and Mercury — will align in the sky.
Four of them (Jupiter, Saturn, Venus, and Mercury) will be easily visible to the naked eye. For Uranus and Neptune, get a pair of binoculars or a small telescope.
The Moon, about 90% illuminated, will also be in the sky, appearing very close to Jupiter. This will create a particularly beautiful view.
F.A.Q.
What color is Jupiter?
Jupiter is a beautifully colored planet covered with mainly white, orange, brown, and red clouds; the Great Red Spot has a reddish-brown color.
Who discovered Jupiter?
Jupiter was known from ancient times, but the first person who provided detailed observations was Galileo Galilei in 1610.
Can a human live on Jupiter?
Well, landing on Jupiter is a bad idea for human beings. The word “land” itself isn’t very appropriate since there is no solid land on Jupiter. You would fall inside the planet until you reach its core, experiencing a thousand times stronger pressure than on the Earth on the way.
What is between Mars and Jupiter?
There is the asteroid belt between the orbits of Mars and Jupiter. This donut-shaped region contains solid, irregularly shaped bodies of different sizes and shapes called asteroids and minor planets.
Where is Jupiter in the sky?
The easiest way to find Jupiter in the sky is to use the free stargazing app Sky Tonight. Just tap the magnifier icon, type “Jupiter” in the search field, and tap the target icon next to the corresponding result. The app will show you the planet’s position in your sky.
Did you know?
- Jupiter has no seasons due to a very small tilt of only 3 degrees. Instead, there are a lot of long-term storms on the gas giant.
- Jupiter is a failed star. It would need more than 70 times its current mass to start a nuclear fusion process and become a real star.
- Jupiter has the largest ocean in the Solar System — it’s made of hydrogen instead of water.
- Jupiter has the strongest magnetic field of any planet in the Solar System.
All about Jupiter: Bottom line
Now you know all the basic facts about Jupiter — from its size to upcoming exploration missions. Want to test your newly gained knowledge? Take our fun quiz about the gas giant! To easily find and identify Jupiter in the sky in your location, use the Sky Tonight app.
Wishing you clear skies and happy observations!
