Observe the sky: October 2025

After the rains of the last days of September, we begin October with unmistakably autumnal weather. Granada-style autumn: chilly mornings followed by warm midday sunshine. For those spending their first year in Granada, you’ll get used to it. But let’s get to the point before I start rambling. We kick off the month with a lunar observation, though it’s a bit uncertain due to the weather forecast—let’s hope we get lucky. Also, this month features two notable meteor showers in addition to what we’ll detail below. The Draconids will peak on the night of October 8, while the Orionids will reach their peak on the night of October 21. The latter will be the best night to spot a few meteors, as it coincides with the new moon.

Day	Time	Event
6	02:30	Moon in conjunction with Saturn, 3.33° N of Saturn
7	05:49	Full Moon
8	15:45	Moon at perigee ( 359775 km)
13	20:14	Moon in its last Quarter
14	01:50	Moon in conjunction with Jupiter, 4.18° N of Jupiter
17	07:53	Jupiter at quadrature
19	20:27	Moon in conjunction with Venus, 3.25° S of Venus
20	09:04	Mercury in conjunction with Mars, 1.98° S of Mars
21	14:26	New Moon
23	12:59	Moon in conjunction with Mars, 4.30° S of Mars
23	17:00	Moon in conjunction with Mercury, 2.16° S of Mercury
24	00:59	Moon at apogee ( 406449 km)
29	18:22	Moon in its First Quarter
29	23:22	Mercury greatest eastern elongation ( 23.88°)

Table 1: Main astronomical events of the month of October. Local time.

October is a month of transitions—days clearly grow shorter while nights stretch longer, all due to the apparent shift in the Sun’s position in the sky. Over the course of this month, the Sun will lose a striking 12º in altitude. As for the Moon, it’s worth noting that the full Moon and perigee (the point in its orbit when it’s closest to Earth) nearly coincide. Truth be told, this alignment holds little scientific or observational significance. But since we’re all headline-hungry these days, this Moon will be dubbed a “Supermoon” or even a “Harvest Moon”. It’s true that when the full Moon aligns with its closest approach, it appears slightly larger and a bit brighter. Still, you likely won’t notice much difference compared to previous or upcoming months.

Sun during October 2025. — **Figure 1:** Variation of the Sun's position during the month of October. Left: Maximum daily elevation of the Sun during the month. Right: Position in the sky if observed every day at the same time (12.00 UT). In orange the positions of the Sun throughout October; in yellow, throughout the year (analemma).

Moon during October 2025. — **Figure 2:** Observability and illumination of the Moon during the month of October 2025. In red the time zone (universal time, UT; local time = UT + 2) during which you will be able to observe the Moon. The vertical white lines indicate the time of the Moon's passage through the local meridian.

Moon during October 2025 (II). — **Figure 3:** Phases and Moon orbit during October 2025.

October is a striking month, as we’ll only be able to comfortably and reliably observe the gas giants—those beyond the asteroid belt. Saturn, Neptune, and Uranus will be visible throughout the night in the constellations of Pisces (the first two) and Taurus (Uranus). And as always, for those with a small telescope, here’s a table to help you enjoy the events involving Jupiter’s satellites this October (Jupiter table).

Planets observability towards the beginning of October 2025 — **Figure 5:** Observability of the different planets of the Solar System from Granada in October 2025. In red, the time zone (universal time) during which you will be able to observe the different planets. The vertical white lines indicate the time of the passage of the various planets through the local meridian.

Planets observability towards the middle of October 2025 — **Figure 5:** Observability of the different planets of the Solar System from Granada in October 2025. In red, the time zone (universal time) during which you will be able to observe the different planets. The vertical white lines indicate the time of the passage of the various planets through the local meridian.

Planetary situation for the month of October 2025 in Granada. — **Figure 6:** Representation of the sky that will be observable at the end, beginning and middle of a typical October night from Granada (October 14th is chosen as representative). The positions of the planets as well as their motion relative to the fixed stellar background are indicated. For the planets with less apparent motion (Jupiter, Saturn, Uranus and Neptune) a zoom is included for tracking with telescopes.

As for the stars, as we’ve been noting since September, we leave behind the spectacle of the summer sky—dominated by the galactic center—and transition to a more austere sky. It’s now ruled by the Great Square of Pegasus, Cassiopeia, and Perseus, with standout objects including the Andromeda Galaxy (M31), M34, and the Pleiades (M45).

The sky over Granada during the month of October 2025. — **Figure 7:** Representation of the sky that will be observable on a typical October night from Granada. The ecliptic is indicated (dashed line) as well as the main deep sky objects.

And now moving into the realm of artificial satellites, here comes the section dedicated to the International Space Station in “Observe the Sky from Ciencias.” At the following link, you’ll find a table (ISS table) listing the main ISS passes visible from Granada during October. This month, we highlight the pass on October 1st around 20:35, with a peak magnitude of -3.1. This pass will also appear to approach the Moon (in projection, of course) around 20:47. If you swing by Paseíllos, you’ll be able to observe it with us!

With that, we wrap up this brief summary of the astronomical events we’ll enjoy throughout October—a month when we’ll begin our observations, which we hope will be more fruitful than last year’s. As always, we remind you that we’re open to suggestions via our Telegram channel, where you can also stay informed about upcoming activities and receive timely alerts for easily observable astronomical events and much more. Here’s the link! We hope to see you soon at our events. Wishing you a great start to the academic year—and see you at Ciencias.

Clear skies!