Jupiter racing toward opposition on November 2-3, 2023

Jupiter and its stormy atmosphere as seen by the Hubble Space Telescope on September 4, 2021. Image via Amy Simon (NASA-GSFC)/ Michael H. Wong (UC Berkeley)/ Hubblesite.

Earth will fly between the sun and Jupiter – bringing Jupiter to its yearly opposition – on November 2-3, 2023. That’s one day after Jupiter reaches perigee – its closest point – to Earth.

Jupiter in 2023: Maybe you’ve noticed Jupiter. It’s been the very bright object ascending in the east earlier each evening. Brighter than all the stars!
It reaches opposition on November 2-3 at 5 UTC (12 a.m. CDT) bringing Jupiter opposite the sun in our sky. It happens as Earth flies between the sun and Jupiter.
Jupiter is closest to Earth not on the day of opposition, but one day earlier, overnight (by American clocks) on November 1-2. At that time, its distance will be 3.982 astronomical units (Earth-sun units, aka AU)/ 370 million miles/ 595 million km/ 33.11 light-minutes from Earth.
Opposition constellation: Aries the Ram.
Brightness at opposition: Magnitude -2.9. Jupiter will shine as the 4th-brightest object in the sky, after the sun, the moon and the planet Venus. It’ll be the brightest starlike object visible for most of the night (until Venus rises before dawn).
Size at opposition (as seen through a telescope): 49.45 arcseconds across.
Through binoculars (anytime): Jupiter reveals a bright disk. If you look closely, you’ll see several of its four Galilean moons appearing as pinpoints of light, arrayed in a line that bisects the giant planet.

On November evenings, look for Jupiter above the eastern horizon after sunset. It lies in the dim constellation Aries the Ram. Jupiter – the 2nd brightest of all planets – reaches opposition at 5 UTC on November 3, 2023. At opposition, Jupiter is 33 light-minutes (3.992 AU) distant from Earth. The beautiful star cluster Pleiades is near the giant planet. Chart via John Jardine Goss / EarthSky.

For precise sun and Jupiter rising times at your location:

Old Farmer’s Almanac (U.S. and Canada)

timeanddate.com (worldwide).

Stellarium (online planetarium program)

In-the-sky information and finder chart for your location

Opposition happens when Earth flies between an outer planet, like Jupiter, and the sun. Illustration via Chris Peat/ Heavens-Above.

How often does Jupiter reach opposition?

Jupiter takes 12 earthly years to orbit the sun once. So Jupiter comes to opposition roughly every 13 months. That’s how long Earth takes to travel once around the sun relative to Jupiter. So – according to our earthly calendars – Jupiter’s opposition comes about a month later each year. Add to that the fact that there are 12 constellations of the zodiac. And there are 12 months in a year. So Jupiter is in a new zodiacal constellation at each year’s opposition (last year, Pisces; this year, Aries).

2023 Jupiter opposition – November 3
2024 Jupiter opposition – December 7
2026 Jupiter opposition – January 10
2027 Jupiter opposition – February 10

Jupiter events in 2023

January 20, 2023: Jupiter’s perihelion or closest point to the sun.
April 11, 2023: Jupiter at solar conjunction, or behind the sun as seen from Earth.
September 4, 2023: Jupiter begins retrograde motion, or westward motion on the sky’s dome, a sign that opposition is coming.
November 1, 2023: Jupiter at perigee, or closest to Earth for 2023.
November 3, 2023: Jupiter at opposition, or opposite the sun as seen from Earth.
December 30, 2023: Jupiter ends retrograde motion, a sign that the best time of year to observe Jupiter is ending. But the planet will remain somewhere in our night sky for many more months, and in fact is visible somewhere in our night sky for most of every year.

A comparison of the apparent size of Jupiter at opposition (November 1-2, 2023) and when it is most distant from the Earth at solar conjunction (May 18, 2024). Image via Dominic Ford’s In-the-Sky.org. Used with permission.

View from above the solar system, November 2023

View larger. | Heliocentric view of solar system, November 2023. Chart via Guy Ottewell. Used with permission.

A failed star

Perhaps you know that Jupiter isn’t a rocky planet like Earth. It’s more like a failed star, not massive enough or hot enough inside to spark thermonuclear fusion reactions, but some 2 1/2 times more massive than all the other planets in our solar system combined. Jupiter is big! But without that thermonuclear reaction it can’t shine as stars do.

You’d need some 80 Jupiters – rolled into a ball – to be hot enough inside to spark fusion. So Jupiter isn’t a star. That is, it doesn’t shine with its own light, but instead by reflected sunlight.

Yet in late October and early November 2023 – as bright Jupiter rises in the east more or less opposite the sunset – you can stand on Earth all night and peer toward bright Jupiter in our sky. And you can imagine that, if the giant planet did have enough mass to shine as stars do, then around Jupiter’s opposition, we’d have no night at all. Instead, Jupiter would shine as a 2nd sun, all night long.

Read more: How to see Jupiter’s moons

In fact, Jupiter (red) completes one orbit of the sun (center) for every 11.86 orbits of the Earth (blue), since our orbit is smaller, and we move faster! Animation via Wikimedia Commons (CC BY-SA 3.0).

EarthSky Community Photos

View at EarthSky Community Photos. | Meiying Lee in Taipei, Taiwan, took these images of Jupiter’s 4 largest moons over the course of a single night. She wrote: “I always thought that to see obvious changes in the 4 major satellites of Jupiter would take several nights of continuous observation. Later, I discovered that the Galilean satellites move very fast around Jupiter.” See the volcanic moon Io move behind Jupiter and emerge on the other side just a few hours later? Amazing! Thanks, Meiying.

View at EarthSky Community Photos. | Meiying Lee in Taipei, Taiwan, shared this chart with us on October 6, 2023, and wrote: “From the evening of August 15 to the early morning of August 16, 2021, the Galilean satellites experienced very exciting changes. Callisto, Ganymede, and Europa passed through the surface of Jupiter one after another, while Io was occulted by Jupiter. This resulted in the rare phenomenon that there was no Galilean satellites around Jupiter for 20 minutes late at night on August 16th. Finally, before dawn, the 4 satellites appeared around Jupiter one after another. I watched the Galilean satellites show all night, it was really exciting!” Thank you, Meiying.

View at EarthSky Community Photos. | Aurelian Neacsu of Visina, Dambovita, Romania, captured this image of Jupiter on August 22, 2023, and wrote: “The bright dot visible on the right bottom corner is not a planet’s satellite; it’s the star Sigma Arietis.” Thank you, Aurelian.

Bottom line: Jupiter will reach opposition on November 2-3, 2023, when Earth will fly between the sun and Jupiter. It’ll be closest to Earth on November 1-2, 2023.

Read more: Jupiter: Closest to the sun November 1, 2023

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