Planetary Conjunctions 2025: Next Stop — Mercury & Saturn
Spotted two "stars" shining side by side? It could be Mercury and Saturn! Use the free Sky Tonight app to check when they’ll rise next in your city. In this article, we’ll dive into what planetary conjunctions are and when you can catch the next ones.
Contents
- What is planetary conjunction?
- Planetary alignment
- Locating planets with Sky Tonight
- When to see two planets close together in 2025?
- Planetary conjunctions: bottom line
What is planetary conjunction?
In simple words, a planetary conjunction occurs when two or more planets appear close to each other in the sky. Such proximity of planets is an optical illusion — in reality, they are very far away from each other.
From an astronomical point of view, a conjunction happens when celestial objects share the same right ascension or ecliptic longitude in the sky.
To really understand what a conjunction is, let's also break down what right ascension and ecliptic longitude are.
Right ascension is the equivalent of longitude on the Earth’s surface projected onto the celestial sphere.
Ecliptic is an imaginary line that marks the Sun’s apparent path across the sky during a year. Ecliptic longitude is measured along the ecliptic eastwards from the Sun’s position at the March equinox. For a clearer understanding of celestial coordinates, explore our dedicated infographic.
When planets are at their closest angular separation but do not have the same right ascension or ecliptic longitude, this is called a close approach. A close approach and a conjunction often occur close together, but not always, so don't confuse these events!
Usually, the distance between objects during a conjunction varies from 0.5° to 9°. To get it better, imagine that 0.5° is the average width of a Full Moon disk. Sometimes planets come even closer — last time it happened with Jupiter and Saturn in 2020 when they appeared less than 0.1° apart. Such an event is called the Great Conjunction and provides a spectacular show for stargazers.
A conjunction can include other celestial objects besides planets — for example, moons, asteroids, or stars. In our article, we list the upcoming conjunctions of the Moon and planets, so you can learn which planet is close to the Moon tonight.
Planetary alignment
Some people confuse a planetary conjunction and a planetary alignment, sometimes referred to as a “planet parade.” In an alignment, more than two planets gather closely in the same area of the sky as seen from Earth. Interestingly, some planets can simultaneously be in conjunction with each other while also part of a planetary alignment. For example, on February 25, Saturn and Mercury will be in conjunction, and for a few days around that date, both will also be part of a full evening alignment alongside Mars, Jupiter, Uranus, Venus, and Neptune.
Curious about planetary alignments and when to see the next planetary parade? Check out our regularly updated infographic!
Locating planets with Sky Tonight
You can easily locate planets in the sky above you with the help of Sky Tonight. Just follow these steps:
- Launch the app and type the name of the planet you're looking for in the search bar.
- Tap the blue target button next to the relevant result, and the app will show you the planet's location on the sky map.
- Tap the blue compass button to find the planet's actual position in the sky above you. A white arrow will appear on your screen, so you can follow it until you spot the planet. The app's image matches the real sky.
When to see two planets close together in 2025?
February 25: Saturn-Mercury
- Close approach: February 25, 09:48 GMT
- Close approach distance: 1°26'
- Conjunction: February 25, 21:27 GMT
- Conjunction distance: 1°40'
Saturn (mag 1.1) will pass close to Mercury (mag -1.2) in the constellation Aquarius. Technically, both planets are bright enough to be visible to the naked eye, but at this period, they will be tricky to see as they will be close to the Sun. Still, it’s worth trying to spot the illusive planets! Saturn and Mercury will also be a part of the great planetary alignment, along with Neptune, Venus, Uranus, Jupiter and Mars. Check out our dedicated article for tips on how to observe the planetary parade.
March 2: Neptune-Mercury
- Close approach: March 2, 12:03 GMT
- Close approach distance: 1°50'
- Conjunction: March 3, 06:24 GMT
- Conjunction distance: 2°10'
Neptune (mag 8.0) and Mercury (mag -0.9) will appear close together in the constellation Pisces. The planets will be visible for about an hour after local sunset. While Mercury will be bright enough to be seen with the naked eye, faint Neptune will require a small telescope or at least binoculars.
March 9: Mercury-Venus
- Conjunction: March 9, 10:52
- Conjunction distance: 6° 21′
- Close approach: March 12, 17:53 GMT
- Close approach distance: 5° 32'
Mercury (mag 0.3) will appear close to Venus (mag -4.4) in the constellation Pisces. The planets will be visible to the naked eye for about an hour after local sunset.
March 28: Mercury-Venus
- Close approach: March 28, 20:24 GMT
- Close approach distance: 5° 39'
Mercury (mag 4.2) and Venus (mag -4.2) will meet in the constellation Pisces. The planets will be visible in the morning sky, right before sunrise. The pair will also be visible during a partial solar eclipse in some locations. However, the sunlight will still be quite bright, and you will need special eclipse glasses to view the event safely.
Want to know more about the upcoming eclipses? Check out our regularly updated infographic.
Planetary conjunctions: bottom line
Planetary conjunctions are beautiful events when planets appear close together in the sky. From an astronomical point of view, they occur when objects share the same right ascension or ecliptic longitude. Don’t miss the upcoming Mercury-Saturn pairing on February 25 — it’s a perfect chance to see these planets side by side. Need help finding them? The Sky Tonight app makes it super easy to locate planets and enjoy the night sky. Happy stargazing!
