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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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Daytime Planetary Imaging

Our next Digital Section webinar will be held on Saturday, March 22nd at 3pm EDT (Noon PDT, 19:00 UT). The topic for that day is going to be planetary imaging during the day, with our own Frank Melillo and Gregory Shanos leading the discussion. Both gentlemen have provided the ALPO with many fine captures of Mars, Saturn, and even Mercury with the Sun still above the horizon. For many observers their setup may not be mobile, and so an obscured horizon means their only real chance to image Mercury would be well before it slips behind the buildings or tree line. Another situation is when an event that you would like to capture is happening during the day, such as a Titan shadow transit.

If you are an ALPO member interested in picking up some tips and recommendations from Greg and Frank, head over to the registration page to reserve your spot via Zoom so that you can participate in the conversation. For non-ALPO members, a recording of the webinar will be made available on the ALPO YouTube channel.

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Read News Headlines

Evidence for a Callisto Ocean
2/20/2025

Researchers investigating Callisto’s magnetic field postulate that the planet’s ionosphere alone cannot account for it, suggesting the need for a thick conductive ocean estimated to be tens of kilometers thick. Starting in 2030, the Europa Clipper and JUICE will perform flybys, most under 1000 km, to provide more data for the existence of an ocean on Callisto.

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.

Check the Events Calendar

All Times are in Universal Time (UT)

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

2025-03-14 06:55
Full Moon total lunar eclipse visible western hemisphere

2025-03-16 20:00
Spica 0.4° north of Moon, occultation Africa and Australia

2025-03-20 17:00
Antares 0.5° north of Moon, occultation Indonesia to South America

2025-03-22
Venus at inferior solar conjunction

2025-03-22 11:29
Last Quarter Moon

2025-03-23
Saturn ring plane crossing

2025-03-24
Mercury at inferior solar conjunction

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

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