By Victor Davis

Welcome Back to Peyton Hall

The February, 2023 meeting of the AAAP will take place IN PERSON on Tuesday, February 14^th at 7:30 PM. As usual, the meeting is open to AAAP members and the public. It’s worth noting that this is Valentine’s Day, and members are reminded to be extra thoughtful toward our life partners who tolerate, and occasionally encourage, our astronomical proclivities.

Hybrid Meeting

You may choose to attend the meeting in person or participate via Zoom or YouTube as we’ve been doing for the past few years. (See How to Participate below for details). Participants who choose to participate virtually will be able to log in to the meeting as early as 7:00 pm to chat informally with others who log in early. We’ve had some security concerns during a past broadcast, so we’re re-instituting the Zoom waiting room. Please be patient for the host to recognize you and grant you entry into the meeting. Be aware that you must unmute yourself to be heard by other participants.

For the Q&A session, you may ask your question using Zoom’s chat feature or you may unmute yourself and ask your question directly to the speaker. To address background noise issues, we are going to follow the rules in the table below regarding audio. If you are not speaking, please remember to mute yourself. You are encouraged, but not required, to turn your video on.

I’ll be out of town for the meeting, but plan to participate via Zoom and introduce the guest speaker as usual.

Featured Speaker: John Church, PhD
Retired Research Scientist
Long-time member of AAAP
j.church@mindspring.com

Cosmic Clockwork: Occultations, Eclipses, and Transits Occultations, eclipses, and transits are among the most impressive solar system events we can observe.  Once portents of doom or omens of the machinations of deities, these events are vivid illustrations of celestial mechanics. Our ability to predict them accurately signals the attrition of magic into rational thought. Nevertheless, they are magical events. At no other times can we get such a sense of the power associated with the movement of massive objects in our relatively near cosmic neighborhood.  In particular, a total solar eclipse is an unforgettable experience as the entire landscape quickly darkens and the sun’s magnificent corona appears for a short time.

These events have also been of deep scientific interest on many occasions.  Transits of Venus were formerly used to determine the scale of the solar system.  Timings of lunar occultations helped refine long-term estimates of the gradual recession of the moon.  Historical records of ancient eclipses were useful in pinning down the gradual slowing of Earth’s rotation due to tidal friction.  Studies of the sun’s corona enabled advancements in solar physics.  Modern techniques have largely taken over in these areas, but such occasions will always remain of deep human interest.

John Church, PhD
A native of Richmond, John Church graduated from the University of Virginia with a bachelor’s degree in chemistry and then earned M.S. and Ph.D. degrees from Lawrence University in Appleton, Wisconsin.   His thesis work was concerned with the reaction of crystalline carbohydrate derivatives with oxygen under relatively mild conditions.  He spent his career in research and development with American Can Company at their Corporate R&D laboratory in Princeton and then with Colgate-Palmolive at their Corporate Research Center in Piscataway.

John is the author of sixteen scientific, historical, and technical publications, including several on the optics of refracting telescopes as well as one on close conjunctions of Jupiter and Saturn.  He holds ten U.S. patents and is the author of a book chapter on the chemistry of bleach. He has written three books and edited several others.  One of his Sky & Telescope articles traced the history of the 6 ¼ inch Hastings-Byrne refractor now installed in our observatory in Washington Crossing State Park, which he and many others helped build in the late 1970’s.

John has served as Assistant Director, Director, and Program Chair of the AAAP.  This September will mark his 53rd year as a club member.  His civic activities include presently serving on the West Windsor Township Zoning Board of Adjustment.  He is married and has three children and six grandchildren.

In 2017, John organized a trip to Oregon to watch the Total Solar Eclipse. He recorded the visit in this document “The Total Eclipse“.

AAAP webcast:  This month’s AAAP meeting, beginning with Rex’s opening remarks and ending at the beginning of the business meeting, will be webcast live on YouTube and recorded for subsequent public access on AAAP’s YouTube channel. Be aware that your interactions during this segment, including questions to our guest speaker, may be recorded for posterity.

Join YouTube Live to listen to the speaker John Church using the link below –

AAAP February 2023-John Church, PhD on “Cosmic Clockwork: Occultations, Eclipses, and Transits “

This session will be recorded and saved on YouTube. Send me an email at program@princetonastronomy.org if you have any concerns

Using Zoom: While we are social distancing, the AAAP Board has chosen to use Zoom for our meetings, based on our belief that many members have already used Zoom and have found it easy to use. One of its great features is you can choose whether you want to install the software on your computer or use it within your browser.

NOTE: The Zoom site has many training videos. If you’re unsure how Zoom works you might want to view the videos on how to join a meeting or how to check your computer’s audio and video before the meeting.

How to Participate:

• Please make sure you have Zoom installed on your computer. You do not need a Zoom account or to create one to join the meeting. Nor are you required to use a webcam.
• Please see below for the link to the meeting, or visit our website.

Join Zoom Meeting Link,   Meeting ID: 845 6648 2175   Passcode: 138071

There is no “Unjournal Club” presentation scheduled this month. As you may know, guest speakers receive a baseball cap with the AAAP logo embroidered upon it as a “thank you” for making a presentation to us. We’re expanding the hat giveaway to members who contribute an “Unjournal Club” presentation to encourage participation.

We hope to make these short presentations a regular feature of our monthly meetings. We’d like to know what members are doing or what members are thinking about in the broad range of topics encompassed by astronomy. A brief ten-minute (or so) presentation is a good way to introduce yourself and the topics you care about to other club members. If you are interested in presenting a topic of interest, please contact either director@princetonastronomy.org or program@princetonastronomy.org.

A look ahead at future guest speakers:

March 14, 2023	Joe DePasquale, Space Telescope Science Institute Joe is Senior Data Imaging Developer in the Office of Public Outreach at the Space Telescope Science Institute. A colleague of January’s guest speaker, Alyssa Pagan, Joe will describe his work turning data from the James Webb Space Telescope (JWST) into images combining science and art to illuminate our perspectives on our universe.
April 11, 2023	Ira Polans, former Program Chair of AAAP Ira will speak briefly on The Anasazi of the Southwest: Chaco Canyon and the Sun Dagger and then introduce the film The Sun Dagger, narrated by Robert Redford. The film tells the story of its exciting discovery in the 1970s by Washington artist Anna Sofaer and its subsequent investigation. It also examines the life and culture of the Anasazi (Ancestral Puebloan) Indians who built the calendar and thrived in the arid canyon environment a thousand years ago. Since then the sun dagger has marked the seasonal solstices and equinoxes in vivid symbolic images of light and shadow on stone. Join us to learn more about this fascinating discovery!   NOTE: This film is solely for in-person viewing, as copyright restrictions will not permit broadcasting it on the internet. This meeting will not be a hybrid meeting.
May 9, 2023	Alain Maury, Astronomer and discoverer of comets and asteroids. Alain Maury operates a time-sharing observatory near San Pedro de Atacama, Chile. He’s also an active observer and discoverer or co-discoverer of several dozen comets and asteroids, several of which (i.e. 3780 Maury) were named in his honor. He’ll talk about his observatory, its operation, and his numerous astronomical activities.
June 13, 2023	Bill Murray, AAAP’s Outreach Director and staffer at NJ State Museum planetarium Bill will give his traditional planetarium show at the New Jersey State Museum in Trenton.
	Summer Hiatus
Later this fall	Gary Rendsburg, Distinguished Professor of Jewish Studies and History at Rutgers Prof. Rendsburg will talk about “The Jewish Calendar,” with emphasis on its astronomical connections to lunar months, intercalated month to adjust to the solar year, festival days, and new moon observances.

As always, members’ comments and suggestions are gratefully accepted and much appreciated.