October 2025 presents itself as one of the most attractive months of the year for astronomical observation from Argentina. The combination of meteor showers, lunar conjunctions, and supermoons offers multiple opportunities to connect with the night sky without the need for telescopes or specialized equipment.
Orionids: meteor shower with guaranteed dark sky
October 21 will be the peak of activity, with up to 20 meteors per hour.
The Orionids are an annual meteor shower that occurs between October 2 and November 7, reaching its peak on the night of the 20th to the 21st.
These meteors come from the remnants of Halley’s Comet, and although the radiant is located in the constellation of Orion, they can be observed all over the sky.
- Origin: Halley’s Comet
- Peak: October 21
- Frequency: Up to 20 meteors per hour
- Ideal condition: New Moon on the 21st, ensuring a dark sky
To enjoy them, it is recommended to find a place away from light pollution, with a clear horizon, and to observe between midnight and dawn. Bringing warm clothing, a blanket, and patience is key for a full experience.
Lunar conjunctions: celestial encounters with bright planets
The Moon will share the sky with Saturn, Jupiter, Venus, Mars, and Mercury.
During the remainder of October, unique astronomical postcards can be observed:
- October 13: Moon and Jupiter at night
- October 19: Moon and Venus at dawn
- October 23: Moon, Mars, and Mercury at dusk
These conjunctions are visible to the naked eye and offer opportunities for amateur astronomical photography and community celestial education.
Mercury at its best moment of the year
On Wednesday 29, Mercury will be in its most favorable position for observation, just after sunset over the western horizon.
This phenomenon marks the best time of the year to see the planet closest to the Sun without optical instruments.
Harvest Supermoon: tradition and science in the sky
The last supermoon of the year was observed on October 6, with intense light and orbital proximity.
The Harvest Supermoon, observed on October 6, is the full moon closest to the autumn equinox. Although the term “supermoon” has no strict astronomical definition, it refers to a full moon at perigee, that is, at its closest point to Earth.
- Origin of the name: Agricultural tradition, taking advantage of moonlight to extend harvests
- Technical definition: Full moon within 90% of the orbital perigee
- Upcoming dates: November 5 (the closest of the year) and January 3, 2026
Recommendations for astronomical observation
Preparation, patience, and connection with the natural environment.
- Location: Move away from urban lights and seek clear skies
- Time: Spend at least 30 minutes for your eyes to adjust to the darkness
- Comfort: Bring warm clothing, a blanket, a hot drink, and a reclining chair
- Recording: If you wish, capture the moment with your phone or camera
