What’s up in the night sky: January 2025

Welcome to our night sky monthly feature where we focus on easy and fun things to see in the night sky, mostly with just your eyes. This month is a spectacular time to check out planets: there is a planet parade across the evening sky including Mars at opposition looking its brightest for a couple of years, as well as the standardly super-bright Venus and Jupiter. Also, this month we’ll see a planetary alignment — an often confusing, sometimes misleading, term that we’ll explain.

All month: In the evening, from west to east along an approximate line crossing the sky, see super bright Venus, yellowish Saturn, very bright Jupiter, and reddish, very bright Mars! If you’ve got binoculars you might see Uranus as well, and a telescope could get you Neptune. Some individual planet notes follow. 

All month: Venus is stunning in the evening west. The brightest natural object in the night sky except the Moon, Venus is particularly easy to see this month as it is far above the horizon in the early evening. It will drop lower as the months pass.

All month: Yellowish Saturn is visible in the eastern sky in the evening. 

All month: Reddish Mars rises in the east in the mid-evening. It is now almost as bright as Sirius, the brightest star in the night sky. 

All month: Very bright Jupiter is in the evening east above Mars.

Early January: Mercury is very low in the east in the pre-dawn.

Jan. 1: New Moon

Jan. 3: The Moon is near Venus in the sky. 

Jan. 3: The peak of the Quadrantids meteor shower. This shower tends to be very good (potentially tens of meteors per hour from a dark site) near the peak but is very concentrated so the shower weakens significantly as you get further from the peak. Also, it is much weaker in the Southern Hemisphere. The near-crescent Moon will not interfere much with viewing.

Jan. 4: Earth’s perihelion – Earth is at its closest to the Sun in its orbit.

Jan. 4: The Moon is very near Saturn. 

Jan. 10: The Moon is in the same part of the sky as Jupiter.

Jan. 12: Mars is closest to the Earth and therefore appears the brightest it will get this year. 

Jan. 13: Full Moon

Jan. 13: Mars is very near the Moon.

Jan. 16: Mars is at opposition – the opposite side of the Earth from the Sun. It will rise around sunset and set around sunrise. If both planets’ orbits were exactly circular, this also would be the closest point in the orbits for this time around. Because the orbits are actually elliptical, the closest point (Jan. 12 this year), is a few days from opposition.

Jan. 18: Venus is relatively close in the sky to the much dimmer Saturn. They will grow farther apart after this date.

Jan. 21: We get what is often referred to as a planetary alignment, which in this case represents when six planets (four visible with just your eyes), can be seen in the sky at once. Viewing them is just as good many days before and after, so don’t worry if you don’t look on this night. For more on “planetary alignment,” see below.

Jan. 29: New Moon

Notes on planetary alignment

So-called “planetary alignments” are fun because you can see multiple planets in the sky at one time, but they are often presented in such a way as to be accidentally misleading. People often think a planetary alignment means the planets involved are perfectly aligned in a line headed away from the Sun. In reality, the planets aren’t always in a perfect line because they aren’t exactly in the same plane. An alignment just means that multiple planets are all visible in the sky from Earth.  It is common, in fact pretty much normal, to have more than one planet up at the same time, thus lined up. What is somewhat unusual is getting so many up in the sky at the same time.

Often, planetary alignments are assigned one date, e.g., Jan. 21, 2025. This is when all planets visible in the line have the smallest arc on the sky, which in this case is still nearly from one side of the sky to the other, west to east. That is often presented in the press as the only date of a magical event. But viewing them is just as good many days before and after, so don’t worry if you don’t look on that particular night.

 From now until around the end of February is a great time to see lots of planets conveniently all in the evening sky. Go out and see them some time during the next many weeks. But don’t worry if you miss the exact date being tossed around as “the” planetary alignment.