Ancient astronomy comes to life
We’ll immerse ourselves in the history of astronomy from the ancient Greek perspective when we meet again via Zoom on Oct 13 at 7:30 (see Ira’s section below for info on the guest speaker and Zoom link). The Greeks developed an Earth-centered system of the universe that guided western thought for two millennia, although that was not the only view. Hipparchus, considered the father of trigonometry and one of the greatest ancient astronomical observers, compiled the first star chart (129 BC) with celestial longitudes and latitudes for 850 stars. This was the first astrometric survey. The catalog itself vanished in the fog of antiquity although it was drawn upon by Ptolemy centuries later in his profound work The Almagest. Interestingly, Hipparchus himself was one of the first to propose a heliocentric solar system, a radical alternative to the Earth-centric universe. Yet he later abandoned it because the calculated orbits were not perfectly circular, an absolutely mandatory criterion in the science of the era. The rejection of heliocentrism by Hipparchus and Aristotle dominated western thought for almost 1800 years, until the Copernicus revolution in the 1500’s finally got it right.

AAAP Astrovideo Project

Summary of Proposal

The trend to virtual meetings and audio-video technologies is widespread across the US and expected to continue in life after Covid. The obstacles to being an active astronomy club can be overcome by audio-video technologies, in fact we have few alternatives. I believe that AAAP should expand its involvement in these areas and help members apply them in an astronomy context. This will draw on the skills of experienced members and provide a path for all members to develop better skills and knowledge in the related hardware and software. The following goals are proposed. Note the proposed dates in the details section below.

(1) Provide members with regular opportunities to participate in live astrovideo in the form of Zoom sessions with electronically-assisted astronomy (EAA). Use these sessions to illustrate the techniques of astrovideo and also astrophotography, described below under Details of Proposal. Where appropriate these live sessions can also be recorded and made available on the website to members and the public.

(2) Encourage and assist members interested in taking part in audio-video recordings covering interviews, instruction about astrophotography, EAA technologies, reviews of software and hardware, and astronomy science topics in general. The recordings, for example MP4 files, would be made available on the club website and potentially elsewhere.

(3) Toward these goals, I propose once-a-month live Zoom video events (dates listed below). In clear weather these sessions would feature live astrovideo sky tours via Zoom originating from the club’s Observatory and members’ telescopes with EAA capability. On cloudy nights the sessions could be a forum for “how-to” discussions of astrovideo and astrophotography, hardware and software demo’s, and astronomy talk. If desired the Zoom sessions could be recorded, potentially providing content for goal (2) above.

Details of Proposal

1. Astrovideo is electronically assisted astronomy (EAA). EAA is telescope imaging with dedicated CMOS or CCD cameras with short exposures (often 5-20 seconds, repeatedly) using specialized software in real time to align and stack frames and reduce noise, giving a near-live video display of what the telescope is seeing. One key is having a sensitive camera capable of high speed download rates. With the right equipment, the method works remarkably well to show deep sky objects in color that are poorly visible by eyepiece, especially in light polluted skies. Examples include the recent astrovideo session in Sept using Zoom to stream EAA from a few members’ telescopes; and the videos Dave Skitt has posted on the AAAP website under “Member Videos” at the bottom of the front page of our website https://www.princetonastronomy.org/. There seems to be strong interest about this in the club.

2. Astrophotography is basically long exposure astrovideo with a lot of computer processing. Astrophotography is related to EAA but uses generally much longer exposures (often several minutes each) with specialized cooled CCD or CMOS cameras (sometimes DSLRs). There is plenty of overlap in the hardware choices, and some cameras can do well in either genre. The image sub-frames are saved on the PC and processed later for aligning, stacking, noise reduction, etc., to create high quality astrophotographs. This is closely related to EAA in telescope and camera technology and software, however, it is more demanding of equipment. An excellent-tracking telescope mount is needed and a guide-scope or off-axis guider is advised. Examples can found in the links on the club’s website at the bottom of the main page under “Club Astrophotography” at https://www.princetonastronomy.org/. There seems to be significant interest in this in the club.

3. Instructional audio-videos on astronomy and astrotech can help members on the learning curve. This means creating digital audio-videos about astronomy with members, for example using modern DSLR video-capable cameras with audio input (cell phones are not ruled out though they typically result in lower quality production). Future content could include a range of club members’ interests, such as technical instructional videos, software and hardware reviews, astronomical science topics. The output files, e.g., MP4 format, can be streamed via Youtube or Vimeo and linked on our AAAP website for member and public access. Examples include several videos produced this summer by member Rich Sherman with a few of us, also videos produced by Dave Skitt, available under the “Member Videos” tab at the bottom of the front page of the AAAP website https://www.princetonastronomy.org/. This is an opportunity for members to step forward to be interview subjects or producers of new videos. There seems to be substantial interest in having access to relevant “how-to” content on the website.

Please get these Zoom meeting dates on your calendars: Oct 16, Nov 13, Dec 11, Jan 15, Feb 12, Mar 12, Apr 09, May 14, June 11, July 09, Aug 06, Sept 10. These are the Fridays each month near the new moon, which provides optimal sky conditions for astrovideo and astrophotography. Starting times and Zoom links for members will be sent prior to each event.

I am asking members to think about whether we want to record these Zoom astrovideo events, and broadcast them as live or recorded video streams. If so, what about editing to make the content more enjoyable and cut out unproductive time. Think about how this could be done, whether it is desired, and who would want to spend time doing it.

I welcome your comments, either by e-mail (director@princetonastronomy.org) or at the Oct 13 AAAP Zoom meeting.