Summer 2024 ‘Strolling Astronomer’ Now Available

June 26 —The digital version of the summer issue of the quarterly Journal of the Assn of Lunar & Planetary Observers is now available for downloading to all paid-up members and various research institutions. Those wishing to join the ALPO should note that an annual membership starts at only $22. Contact Membership Secretary Matthew Will at for complete details.

Abbreviated as “DJALPO66-3″; this issue includes the following:

•    In our Point of View opinion column, Journal Editor Shawn Dilles offers his thoughts on how the ALPO seems lucky to see new contributors as others back away after many years of contributing. Yep, we’re always on the lookout for new contributors.
•    A roundup of general interest news, including important updates about several of our observing sections, news about the upcoming summer ALPO conference and more.
•    A look back at selected goings-on in The Strolling Astronomer 75, 50 and 25 years ago as presented by Carl Hergenrother.
•    Solar Section Coordinator Rik Hill provides the latest Carrington Rotation Report, this time, it’s rotations 2276 thru 2279. Among the conclusions is while there are some indications that this cycle may be reaching a climax in this calendar year, other data seems to suggest a “double-humped maximum” like we saw in cycles 24 and 23. We’ll see.
•    From Theo Ramakers, an extremely detailed analysis of the first four years of Solar Cycle 25, where he compares three different solar activity criteria between Cycle 24 and Cycle 25.
•    From Mercury Section Coordinator Frank Melillo, a report on the various appearances of his planet in 2022.
•    A paper by new contributor Dr. Oleksiy Arkhypov about sunlight forward scattering by the global dust envelope of the Moon causing a rare and forgotten phenomenon of an “Annular Moon.”
•    Two very interesting explanations about the hook-like shadow that occasionally appears on the floor of the lunar crater Plato — one by our Lunar Domes Studies Program Coordinator Raffaello Lena and another report by observer K.C. Pau.
•    From our Mars Section Photometry Coordinator Richard Schmude, a report on Photometric Brightness Measurements of the red planet in 2022-2023.
•    From our Remote Planets Section Coordinator (also Richard Schmude), a summary of the various reports he’s received about our far-out solar system neighbors during 2022-2023.
•    A directory of who’s who and what’s what of all things ALPO in the “ALPO Resources” section.

These reports and those who produce and contribute to them are what make our organization so vital to observational solar system astronomy. We are extremely proud of the work they do.

Use the various e-mail addresses and hyperlinks (in blue text) throughout this issue to instantly e-mail authors and ALPO staff members. The Table of Contents is also hyperlinked to make it easy to jump directly to a desired article.

As always, this issue is requires the free utility Adobe Reader (Version 7.0 or higher) available at

To access earlier digital issues of our Journal back to Issue 1, go to our homepage at, click on the “ALPO Section Galleries” link near the top-right corner of the screen, click on the “Publications Section” icon, then the “ALPO Journals” icon, and finally the icon for the desired volume and year. Afterwards, choose the desired “Strolling Astronomer”.

The ALPO thanks the following for their continued support of the ALPO:
•    Sky & Telescope magazine (and its owner, the American Astronomical Society); Sky & Tel has maintained its outside back cover ad on the Journal without fail since 1960 and we look forward to many more years of this.
•    Celestron Telescopes
•    The makers of both the Catseye Collimation System and Catsperch Observing Chairs

Please patronize these good folks who advertise in our Journal in return for their support of us.

Call for Observation Reports of the April 2024 Total Solar Eclipse

As the Total Solar Eclipse of 2024 becomes a memorable astronomical event witnessed by many, it will be preserved and shared by observers through documented visual observations and vivid personal recollections.  The ALPO wishes to share all the depth and nuance of this experience as well as its scientific and measured magnitude in an upcoming issue of Journal of the ALPO.

(Image here by Justin Maune taken at Kimball Bend Park in Central Texas)

Please send your observations and reports — whether they be images, drawings, diagrams, or written documentation and descriptions — to:


Reports should include the following information and data:

Observer’s name and exact location of the observation. Include an actual address, the city, state, and country or if in a rural location, an approximation, as well as latitude and longitude from where you observed the eclipse.

Date and time (Universal Time preferred) include “eclipse contacts” would be helpful.
•    First contact occurs when the partial phase of the eclipse begins
•    Second contact is when a total phase begins
•    Third contact is when the total phase ends
•    Fourth contact occurs when the partial phase ends.

Include an exact time for any specific events or observations observed with the naked eye or with instrumentation.

Instrumentation details including type of optical aid (telescope, binoculars, naked-eye, etc.), focal length, aperture (inches or mm), filter details (if used).

If imaging the eclipse, what kind of camera was used? DSLR, DSLM, webcam or CCD.  Give details (brand and model), type of lens used and focal length, exposure parameters such as aperture (f/?), ISO, exposure time and any other kind of digital enhancements.  Post processing details (capture and processing programs) should be included if applicable.

Sky conditions should include seeing (steadiness) and transparency as well as general sky conditions.  Report weather descriptions, especially from any weather instruments brought to your site.

Written descriptions and impressions are welcome too, about what was observed at various stages of the eclipse.  This can include observations during the partial phases concerning wildlife, sky darkening, shadow bands just before and after totality, and any other environmental effects.  Be sure to note the time for these events.  For totality, size, shape, and extent of the corona, prominences, chromosphere, etc. are of interest as well as sky colors, visibility of landscape, visual identification of planets, stars, etc., including weather conditions at the time.  Visual impressions of the diamond ring are welcome too.

We hope it was a wonderful eclipse wherever you were and that you will share your observations with us.  The ALPO will analyze and report these observations collectively, in an upcoming issue of the Journal.


The ALPO YouTube Channel is Now Alive!


July 10, 2020 — In another effort to expand our online presence, ALPO Podcast Coordinator Tim Robertson has started an ALPO YouTube channel. While it’s still new, here you will find videos and content — including live streaming of events and tutorials — that support the mission of this organization. To learn more about the ALPO on our YouTube channel, click on the ALPO YouTube Channel link in the upper corner of the right  sidebar on this screen.


Publications Section Bulletin

Are you looking to see if the ALPO ever covered a special solar system event that you remember? Does your current research require specific solar system observational data by the amateur astronomy community? Click Here to go to JALPO Indexes



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ALPO 2021 Conference News
By Tim Robertson & Ken Poshedly,
ALPO Conference coordinators

Due to the continuing nearly worldwide quarantining caused by the Covid-19 pandemic, the 2021 Conference of the ALPO will be held online on Friday and Saturday, August 13 and 14. (This is to prevent a scheduling conflict with the 2021 Astronomical League Convention (ALCON 2021) which will be held in Albuquerque, NM, on August 4 thru 7, 2021.)
The ALPO conference times will be:
Friday from 1 p.m. to 5 p.m. Eastern Time (10 a.m. to 2 p.m. Pacific Time)
Saturday from 1 p.m. to 6 p.m. Eastern Time (10 a.m. to 3 p.m. Pacific Time).
The ALPO Conference is free and open to all via two different streaming methods:
The free online conferencing software application, Zoom.
On the ALPO YouTube channel at
Those who plan to present astronomy papers or presentations must (1) already be members of the ALPO, (2) use Zoom, and (3) have it already installed on their computer prior to the conference dates. Zoom is free and available at
Those who have not yet joined the ALPO may do so online, so as to qualify to present their work at this conference. Digital ALPO memberships start at only $18 a year. To join online, go to, then scroll to the bottom of that page, select your membership type, click on “Add to Cart” and proceed from there.
There will be different Zoom meeting hyperlinks to access the conference each of the two days of the conference. Both links will be posted on social media and e-mailed to those who wish to receive it that way on Thursday, August 12, 2021. The Zoom virtual (online) “meeting room” will open 15 minutes prior to the beginning of each day’s activities.
Those individuals wishing to attend via Zoom should contact Tim Robertson at as soon as possible.
The conference will consist of initial welcoming remarks and general announcements at the beginning each day, followed by papers and research findings on astronomy-related topics presented by ALPO members.
Following a break after the last astronomy talk on Saturday will be presentations of the Walter Haas Observing Award, the Peggy Haas Service Award and the Michael D. Reynolds Astronomy Award. The last one is brand new and was presented to Ms. Pranvera Hyseni several months ago in recognition for her work over the past several years to advance the public’s awareness and appreciation of astronomy.
A keynote speaker will then follow the awards presentations on Saturday. The selection of a keynote speaker is in progress and the final decision will be announced in the summer issue of this Journal (JALPO63-3).
Presentation Guidelines
All presentations should be no more than 15 minutes in length; the preferred method is 12 minutes for the presentation itself plus 3 minutes for follow-up questions. The preferred format is Microsoft PowerPoint.
Send all PowerPoint files of the presentations to Tim Robertson at .
Suggested Topics
Participants are encouraged to present research papers and experience reports concerning various aspects of Earth-based observational astronomy including the following.
New or ongoing observing programs and studies, specifically, how those programs were designed, implemented and continue to function.
Results of personal or group studies of solar system or extra-solar system bodies.
New or ongoing activities involving astronomical instrumentation, construction or improvement.
Challenges faced by Earth-based observers such as changing interest levels, deteriorating observing conditions brought about by possible global warming, etc.
Information about paper presentations, the keynote speaker and other conference data will be published in this Journal and online as details are learned.