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ALPO Announcements

The Upcoming March 14 Total Lunar Eclipse

Members, please get out on March 13-14, 2025 and take some images of the upcoming total lunar eclipse and share them with us here at ALPO on the Eclipse Gallery Page. Please submit your images and observations and share what you witnessed with the entire ALPO community.

When you are ready to report on your eclipse activities and/or post images to the ALPO Eclipse Gallery or blog, please send them to the eclipse@alpo-astronomy.org address. Be sure to follow the guidelines when sending your photos so that they meet the threshold of being sufficiently documented to be of value for subsequent research and evaluation. Please see my notes on annotating the images below. In addition to your reports & images being posted on the Eclipse Blog and in the Eclipse Gallery, some items will be selected to be published in the quarterly on-line and print publication, the Journal of the Association of Lunar & Planetary Observers (“JALPO”).

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Read News Headlines

JWT Captures Neptune Auroras
3/27/2025

The James Webb Space Telescope has achieved a historic breakthrough by capturing auroras on Neptune for the first time. Unlike Earth's polar light shows, Neptune's auroras, driven by its tilted magnetic field, appear near the planet's mid-latitudes. This groundbreaking discovery not only completes Voyager's unfinished work but also opens a new chapter in studying the gas giants' hidden features and mysteries.

The sun's current solar cycle, Solar Cycle 25, has been full of surprises, surpassing predictions with a peak sunspot count of 156.7 in 2024, exceeding earlier forecasts. Scientists debate whether the cycle's solar maximum has already occurred or if another peak awaits later in 2025, as solar cycles can sometimes show a "double peak" pattern. Despite possible signs of decline, experts suggest strong solar activity may persist for a year or more, offering continued opportunities for aurora displays and solar observation.

Check the Events Calendar

All Times are in Universal Time (UT)

2025-03-29 08:50
Partial Solar Eclipse (Europe, Northeast US CA)

2025-03-29 10:58
New Moon lunation 1265, partial solar eclipse Europe

2025-04-03
Jupiter 6º south of Moon

2025-04-05 02:15
First Quarter Moon

2025-04-13 00:22
Full Moon, smallest of 2025

2025-04-13 02:00
Spica 0.3º north of Moon, occultation Central and South America

2025-04-16 23:00
Antares 0.4º north of Moon, occultation Africa to Australia

2025-04-19
Mercury at highest altitude in morning sky

2025-04-21
Mercury at greatest elongation west

2025-04-21 01:35
Last Quarter Moon

Explore our Galleries

Credit: Michael Mattiazzo
Equipment: Canon 6D DSLR and a Sigma 200mm f/2.8 lens
A stack of ten 30-sec shots of Comet C/2024 G3 (ATLAS) just a day or two after the complete disintegration of the comet's nucleus. Near-linear features, synchronic bands and striae, are visible within the dust tail.

Credit: Christophe Pellier
Equipment: 305mm SW Flextube f/5 with ASI462MM camera
Jupiter's NTrZ has been undergoig dramatic change to kick off 2025. Here is an excellent shot showing the two distrubtions (bright white) and their wake of dark material just above the NEB.

Credit: Paul G. Abel
Equipment: 305mm Newtonian in IL and W15, W21, and W47 filters
A marvelous sketch of Venus that documents the cusp anomaly (i.e., the effect whereby the terminator deviates from it's usual path at the poles and becomes much flatter). Also note the presence of both polar cusp caps.

Credit: Michael Teoh
Equipment: Lunt 152mm Solar telescope and QHY5III678M camera
While normally tethered to the Sun, in this sharp image we see a prominence being hurled from the eastern limb of our home star.

Credit: KC Pau
Equipment: 250mm f/6 Newtonian with QHYCCD 290M
A detailed capture of the craters Aristoteles and Eudoxus showing their terraced wall structure. This shot was taken from a balcony of a high rise apartment in Hong Kong, catching the Moon between high-rise skyscrapers!

Credit: Clyde Foster
Equipment: 355mm Celestron Edge HD with PlayerOne Mars camera
Only when Saturn is in its Equinox season can we catch its moons cutting in front of the planet. Here we see the uncommon presentation of its largest moon, Titan, casting its shadow upon the cloud tops below.

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.

Join ALPO

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

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Paying by Mail

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