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The ALPO YouTube Channel

The most recent ALPO webinar, Chairside Processing with Gary Walker, has now been posted to the ALPO YouTube channel. If you weren’t able to catch the webinar live you can now catch it here.

But – did you know that the channel has over 150 videos, including our annual conventions from 2020 through last summer? You’ll also find all episodes of the ALPO’s bi-monthly podcast, the Observers Notebook hosted by Tim Robertson, available to replay. The podcast covers a wide range of topics, from current reports on what’s of interest in the sky to historical context of the study of the Solar System by amateur astronomers.

So be sure to take a moment to check out all the great content available on our YouTube channel. And while you are there be sure to subscribe – that way you’ll never miss when new videos become available with topics such as the Mars Ingenuity Helicopter or Tracking Down Planets in the Daytime!

JALPO Vol 67 No. 1 Available

In this issue...

In our Point of View opinion column, Journal Editor Shawn Dilles offers his thoughts on the “Awe-Inspiring Beauty and Scientific Impact of Amateur Observing.” What you’ll also find inthis issue includes:

A roundup of general interest news, including a request to our membership about possible ALPO items to offer that can subtly promote our organization.
A report from our Membership Secretary as to our current membership categories.
Minutes of the July 26 ALPO Board of Directors meeting.
A look back at selected goings-on inThe Strolling Astronomer75, 50 and 25 years ago as presented by Carl Hergenrother.
A great reminder to all about our fascinating Lunar & Planetary Training Program. Do we need it? You betcha!!! And probably more than most of us realize.
Solar Section Coordinator Rik Hill provides the latest Carrington Rotation Report, this time, rotations 2284 thru 2286. Says Rik: “The activity in these three rotations saw the highest in two solar cycles. While close to the solar max, I would quote Winston Churchill: ‘It is not even the beginning of the end. But it is, perhaps, the end of the beginning.’ ”

Continue reading...

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Read News Headlines

Is the Moon Geologically Dead?
2/2/2025

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.

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.

Check the Events Calendar

All Times are in Universal Time (UT)

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

2025-03-01 23:00
Venus 6° north of Moon

2025-03-02
Jupiter at eastern quadrature

2025-03-05 13:00
Moon 0.6° north of Pleiades

2025-03-06 16:32
First Quarter Moon

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

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

2025-03-09
Mars 1.7° south of Moon

2025-03-12
Saturn at solar conjunction

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

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

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