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Is the Moon Geologically Dead?
2/2/2025
TBD
In recent years, our understanding of the Moon has undergone a significant transformation. For centuries it was thought to be a geologically dead world, but recent discoveries are challenging this notion. Researchers from the University of Maryland and the Smithsonian Institution have found evidence of recent geological activity on the moon's far side. They identified 266 lunar ridges, suggesting that the moon has been active within the past 200 million years and might still be active today.

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Video (and Sound!) of Meteorite Impact
1/17/2025
Live Science Logo
Imagine stepping out for a walk, only to return and find your walkway transformed by a cosmic event. This is exactly what happened to a couple in Prince Edward Island, Canada. Their doorbell camera captured the first-ever video and audio of a meteorite crash-landing right outside their home. The footage shows a fast-moving space rock hurtling towards the ground, creating a loud crash and an explosive burst of gray dust.

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Check the Events Calendar
All Times are in Universal Time (UT)

2025-02-20 17:32
Last Quarter Moon

2025-02-21 09:00
"Antares 0.4° north of Moon, occultation Easter Island to South Africa"

2025-02-28 00:45
New Moon lunation 1264

2025-03-02
Jupiter at eastern quadrature

2025-03-07
Mercury at dichotomy & greatest elongation east

2025-03-08
Mercury at highest altitude in evening sky

2025-03-12
Saturn at solar conjunction

2025-03-14 03:57
Total Lunar Eclipse (Western Hemisphere)

2025-03-22
Venus at inferior solar conjunction

2025-03-23
Saturn ring plane crossing

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Learn about the ALPO

The Association of Lunar and Planetary Observers (ALPO) is an international organization devoted to study the Sun, Moon, planets, asteroids, meteors, and comets. Our goals are to stimulate, coordinate, and generally promote the study of these bodies using methods and instruments that are available within the communities of both amateur and professional astronomers.

The ALPO collects and analyzes observations of various Solar System bodies and associated phenomena and publishes detailed reports concerning these bodies in its quarterly publication the Journal ALPO, otherwise known as The Strolling Astronomer. Membership in the ALPO includes receiving our journal, and back issues can be found in our Publications section.

We welcome and provide services for all individuals interested in lunar and planetary astronomy. For the novice observer, the ALPO is a place to learn and to enhance observational techniques. For the advanced amateur astronomer, it is a place where one's work will count. For the professional astronomer, it is a resource where group studies or systematic observing patrols add to the advancement of astronomy. Further details about the ALPO can be found here.

There are a range of membership levels available starting with annual dues of only $22. See the footer below for links on how you can become a member today.

The Association of Lunar and Planetary Observers (ALPO) is an international organization devoted to study of the Sun, Moon, planets, asteroids, meteors, and comets. Celebrating our 75th anniversary in 2022, our goals are to stimulate, coordinate, and promote the study of these bodies using methods and resources available to both amateur and professional astronomers.

The science of astronomy has never been more exciting or dynamic than it is today - for the novice observer, the ALPO is a place to learn and enhance one’s observational techniques. For the advanced amateur astronomer, it is a place where one's work will matter. And for the professional astronomer, it is a resource where group studies or systematic observing patrols add to the advancement of astronomy.

ALPO members range from enthusiastic individuals with the desire to pursue an initial interest in astronomy to advanced amateurs to professional astronomers deeply involved in lunar and planetary astronomy.

Becoming a member is easy, and we welcome you to join us as we explore and learn more about this vast universe we all call home. Simply select one of the options below to get started.

Paying Online

Please use this link to purchase your membership online via PayPal.

Paying by Mail

Download and complete the ALPO Membership form following the instruction on the form