Northern lights, comets, Mars, eclipses: the 2025 calendar of major astronomical events

The sky is sometimes capricious. Thus, comets often do not meet the brightness estimates that astronomers calculate, but on the whole, humans are good at accurately predicting eclipses, “occultations,” and most observable astronomical events. Here is a selection of what the sky and the stars will offer us spectacular in 2025.

Northern lights and comets?

• The Sun: our star is always at its strongest its peak of magnetic activity responsible for intense northern lights, like last October 10. We can expect a few more episodes like last fall before heading back towards a calmer ten years. Indeed, this peak of solar activity occurs only every 11 years.

• Comets: hairy and unpredictable like rock stars, these stars generally do as they please (who said their tails!?). We know perfectly well how to calculate their trajectory and estimate their luminosity, but we never know what exactly comets are made of. Is their core dense, porous? Will they break up as they pass closer to the Sun? C/2023 A3 Tsuchinshan Atlas did not disappoint and allowed himself to be admired in October.

C/2024 G3 Atlas could be the nice surprise of January 2025. Be careful, its close proximity to the Sun in the sky risks making it difficult to observe at sunset. It is nevertheless possible that it will be visible to the naked eye around January 20 in the Northern Hemisphere.

2025, a year with four eclipses, including one observable in France

No, it's not huge. It's even the minimum possible over a year! There will be two total lunar eclipses and as many partial solar eclipses. Two will be partly observable from mainland France. The lunar eclipse of March 14 in the morning will be visible for a few tens of minutes from 6:09 a.m., but not in its entirety (this site shows it very well).

On September 7 and 8, another total lunar eclipse will be centered on Asia.

A partial solar eclipse visible in France on a Saturday morning!

For solar eclipses, we will be able to take advantage of that of March 29, 2025, which will fall on a Saturday morning! It will be visible at 35% in Paris, 43% in Brest and 21% in Marseille (let's say “half” to honor the Marseille exaggeration). Not so bad.

On the other hand, the solar eclipse of September 21, 2025 will be reserved for New Zealanders or Antarctic penguins.

And the planets? Mars in opposition and four visible planets!

Mars will be atoppositionthat is to say in its most favorable observation period for Earthlings, January 16. That said, it is already perfectly visible from the start of the evening, as we see in these two simulations carried out on Stellarium. Note that we can observe, from west to east: Venus, Saturn, Jupiter and Mars, all in one glance after sunset.

One last notable event, but you will need to have a telescope to take advantage of it: Saturn will offer a rare spectacle in March with the apparent disappearance of his rings because of the plan according to which they will be observed.

Good heavens and happy new year 2025!