This May, the conjunction of Mars and Jupiter will take place. Learn how and when to see it.
What is planetary conjunction?
In simple words, 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, conjunction happens when celestial objects share the same right ascension¹ or ecliptic longitude² in the sky.
¹Right ascension is the equivalent of longitude on the Earth’s surface projected onto the celestial sphere.
²Ecliptic 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.
While the first definition is more common, it isn’t very precise. In fact, it describes a close approach (small angular separation) of space objects — an event that usually takes place near conjunction. But don’t confuse these events! A close approach isn’t necessarily conjunction.
Usually, the distance between objects during 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 — the 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.
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 planetary conjunction and a planetary alignment sometimes referred to as a “planet parade.” Conjunction implies a shorter than usual distance between objects in the sky, while an alignment means that planets line up in a row in the same area of the sky, as seen from the Earth.
May conjunctions
In May, we will see the single fascinating conjunction of Mars and Jupiter. Not to miss it, type “Mars Jupiter” in the Sky Tonight app’s search field and select the fitting result to find the exact timings and coordinates for your location. If you tap the target icon, you’ll see the objects’ position in the sky in the moment of conjunction.
May 29: Mars-Jupiter conjunction
On May 29, 2022, at 08:57 GMT (04:57 a.m. EDT), Mars will meet Jupiter in the constellation Pisces. Jupiter will shine brightly at a magnitude of -2.3, so you can observe it easily with the unaided eye. Mars will be a bit dimmer — with a magnitude of 0.7. The planets will be separated by only 0.6° in the sky but still too far from each other to see them together through a telescope. Try to spot them both with the naked eye or with a pair of binoculars!
In addition to planetary conjunctions, you can enjoy the conjunctions between the Moon and planets. A fair number of them will occur in May.
We wish you clear skies and happy observations!
Text Credit: Vito Technology, Inc.
