A full moon has unveiled an owl-shaped finial on a house in Hede-Bazouges, a suburb of Rennes in western France, just days before Halloween on October 29, 2023.
This week, the largest full moon of 2024 is set to rise. The peak is expected on Thursday, October 17, at 7:26 a.m. EDT, or 11:26 GMT. Just under 11 hours prior, the moon will reach perigee, its closest point to Earth, at a distance of 221,938 miles (357,174 km).
These two phenomena together will create a “supermoon,” which is about 14% brighter than an average full moon and will bring significant tidal changes later this week into the weekend. Dr. Fred Espenak, a retired NASA astrophysicist, defines a supermoon as a full moon that occurs within 90% of its closest approach to Earth. For 2024, there will be four supermoons: in August, September, October, and November, with this week’s event being the closest alignment of a full moon and perigee.
While many weathercasters will suggest that viewers step outside on Thursday to enjoy the “Full supermoon,” the moon will actually be in a waning gibbous phase by that time, further away from the perigee point in its orbit. Instead, Wednesday night will be ideal for observing the effects of the supermoon as it will be very close to perigee and approaching its full phase.
The October full moon, traditionally known as the Hunter’s Moon, signifies the time of hunting as animals prepare for winter.
High tides, known as “spring” tides, are expected when the moon is full or new, as the moon and sun align, enhancing their tidal effects. Conversely, “neap” tides occur when the moon is in its first and last quarters, leading to weaker tides. Interestingly, the highest tide will happen days later, with Boston Harbor reaching its peak on Friday and Cape Fear, North Carolina, experiencing high tide on Saturday.
The phenomenon of a perigee moon, particularly at moonrise or moonset, creates a striking visual effect called the “moon illusion,” making the moon appear significantly larger when close to the horizon, especially near foreground objects. Observers can witness this impressive spectacle by noting local moonrise and moonset times.
For those interested in observing the moon and other celestial objects more closely, various telescope and binocular options are available for purchase.