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ALPO Announcements

Jupiter 2025-26 Webinar

Drs. Richard Schmude and John Rogers will lead an ALPO Digital Section webinar on Saturday, December 13 at 3:00 p.m. EST (12:00 PST, 20:00 UT) to discuss the current Jupiter apparition and targets of opportunity as the planet approaches opposition on January 10. Dr. Schmude, ALPO’s Jupiter Section Coordinator, regularly guides observers on how to contribute scientifically useful images and reports. Dr. John Rogers, Director of the BAA Jupiter Section and one of the world’s most experienced Jupiter observers and synthesizers of visual and imaging data, will complement the discussion with his deep historical perspective and recent analyses of belt and spot behavior.

Jupiter is known as a highly active planet in amateur telescopes, exhibiting belt outbreaks and revivals (most recently involving the SEB and NTB), convective outbreaks in the STB/SSTB region, and long‑lived ovals and disturbances. These are the phenomena that professional and amateur networks have been documenting throughout 2024–25 and into our current apparition.

Whether you contribute visual sketches, methane‑band images, or high‑resolution webcam runs, the webinar will touch upon what to watch for and how to submit observations so they feed ongoing ALPO and BAA analyses. ALPO members may register (here) to participate via Zoom where they will have the benefit of being able to ask questions to the presenters, and the webinar will be freely livestreamed on the ALPO YouTube channel for the broader amateur astronomy community.

ALPO Youth Program Coordinator Needed!

The Association of Lunar and Planetary Observers (ALPO) is seeking an energetic and enthusiastic volunteer to serve as our Youth Program Coordinator.

Responsibilities:

Develop engaging lunar and planetary observing exercises designed for ages 7–18.
Write a quarterly Youth Section report for the Journal of the ALPO (JALPO), highlighting youth activities and observing programs.
Work with guidance from the ALPO Board of Directors—while also having the freedom to shape and grow the program with your own creativity and vision.

Why Join?

This is an exciting opportunity to inspire the next generation of planetary observers and help young astronomers build skills that will last a lifetime. You’ll play a vital role in connecting young people with the wonders of the Moon, planets, and beyond.

If you’re passionate about astronomy education and youth engagement, we want to hear from you!

Apply today if you are an ALPO member and help us inspire tomorrow’s explorers of the universe.

Participate in our Sections

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The ALPO Organization Sections

Read News Headlines

The Hidden Danger of Lunar Micrometeoroid Storms
11/12/2025

A new study quantifies the threat of micrometeoroid impacts to NASA's planned permanent lunar base, showing that up to 23,000 impacts may occur per year. Even microscopic particles carry enough energy to damage equipment and threaten astronaut safety. The research reveals that impact rates vary dramatically by location, with the lunar south pole, the chosen Artemis base site, fortunately experiencing the lowest bombardment.

New images of the interstellar comet 3I/ATLAS reveal it is glowing green and has a surprisingly minimal tail structure as it moves through the inner solar system. The intense green hue is believed to be caused by the irradiation of diatomic carbon, which is excited by the Sun's ultraviolet light. This unique coloration and the comet's overall appearance are providing astronomers with key data about objects originating from other star systems.

The X5.1-class eruption from sunspot AR4274 is this year's most powerful solar flare and Earth is currently in the firing line. The eruption sparked radio blackouts across parts of Africa and Europe, disrupting high-frequency communications. This significant activity, along with recent coronal mass ejections (CMEs), has prompted a geomagnetic storm watch for the coming days as the plasma cloud heads towards Earth.

Check the Events Calendar

All Times are in Universal Time (UT)

2025-11-17
Peak of the Leonid meteor shower

2025-11-17 11:00
Spica 1.2° north of Moon, occultation South America and Antarctica

2025-11-20
Mercury at inferior solar conjunction

2025-11-20 06:47
New Moon lunation 1273

2025-11-22
210P/Christensen at perihelion (0.53 au)

2025-11-22 19:05
Titan begins transit across Saturn (5½ hours duration)

2025-11-23
Saturn Rings nearly edge-on at 0.5°

2025-11-24
C/2025 K1 (ATLAS) closest to Earth (0.40 au)

2025-11-28 06:59
First Quarter Moon

2025-12-01
Start of Carrington Rotation 2305

Explore our Galleries

Credit: Robert Reeves
Equipment: Celestron C-11
The low sun angle seen in this image casts shadows that reveal what many people do not realize; the Straight Wall lies within a large unnamed partial ghost crater tentatively named Ancient Thebit.Spanning nearly 200 kilometers, this half-hidden crater is one of the Moon’s larger craters.

Credit: Keith Bible
Equipment: (Equipment not listed)
A brilliant fireball slices through the Milky Way in this star-strewn photo taken on March 13th of last year.

Credit: Clyde Foster
Equipment: 355mm Celestron Edge, Player One Mars-MII
Mars has shrunk rapidly in the eyepiece this spring, yet here we see a wealth of detail in the Syrtis Major region in this RGB image. Mars was barely 5" at this time, smaller than Mercury's usual size.

Credit: Christian Viladrich
Equipment: Takahashi 150, Basler 1920-155 Camera
A huge promience breaks free from the Sun's grasp and launches into space in this stunning image.

Credit: Gary Walker
Equipment: MCT 254mm f/14.5 with QHY5III200M camera
In the early morning hours of Sept 20th veteran ALPO imager Gary Walker recorded the transit of Saturn's largest moon Titan as well as its shadow among the colorfully striated cloud tops of the Ringed Planet. Shadow transits for Titan are now over and observers will need to wait another 14 years for the next series to begin.

Credit: Paul G. Abel
Equipment: 305mm Newtonian at 230x
Are sketches still valuable? As seen here the resounding answer is "Yes!" This detailed sketch by skilled observer/artist Paul Abel captures many features, including the recent STB outbreak abpve and to the right of the GRS. Sketches also help to provide continuity to our rich archive of sketches that allows comparisons to be drawn.

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

ALPO Announcements

Jupiter 2025-26 Webinar

ALPO Youth Program Coordinator Needed!

Participate in our Sections

Read News Headlines

The Hidden Danger of Lunar Micrometeoroid Storms
11/12/2025

Irradiated Comet 3I/ATLAS Glows Green and Hides Its Tail in New Image
11/11/2025

Strongest Solar Flare of 2025 Sparks Radio Blackouts Across Africa and Europe
11/11/2025

Check the Events Calendar

Explore our Galleries

Learn about the ALPO

ALPO Announcements

Jupiter 2025-26 Webinar

ALPO Youth Program Coordinator Needed!

Participate in our Sections

Read News Headlines

The Hidden Danger of Lunar Micrometeoroid Storms 11/12/2025

Irradiated Comet 3I/ATLAS Glows Green and Hides Its Tail in New Image 11/11/2025

Strongest Solar Flare of 2025 Sparks Radio Blackouts Across Africa and Europe 11/11/2025

Check the Events Calendar

Explore our Galleries

Learn about the ALPO

The Hidden Danger of Lunar Micrometeoroid Storms
11/12/2025

Irradiated Comet 3I/ATLAS Glows Green and Hides Its Tail in New Image
11/11/2025

Strongest Solar Flare of 2025 Sparks Radio Blackouts Across Africa and Europe
11/11/2025