Rounding out the year

November and December will see two excellent speakers present talks, rounding out this most unusual year for the Cuyahoga Astronomical Association’s (CAA). COVID-19 isolation restrictions on group gatherings, and closed meeting facilities caused the club to take its meetings online via the Zoom cloud service. Normally the club hosts a December dinner in lieu of a meeting but since the dinner cannot be held, there will be a December “virtual” meeting complete with speaker.

Suzie Dills

Coming November 9: Suzie Dills, longtime CAA member and director of the Hoover-Price Planetarium in Canton, Ohio, will give a talk entitled “Women in Astronomy.” Dills will tell us stories of female astronomers’ inspirations, science, and contributions which have been and often are unheralded.

Glenn StarkmanDecember 14: Professor Glenn Starkman, co-chair of physics and astronomy at Case Western Reserve University will present “The Big Bang and Beyond.” Dr. Starkman will take us to the beginnings of space and time, and show us what we know, what we think we know, and what we wish we knew.

Attendees may join the Zoom meeting beginning at 7:20 p.m. the nights of CAA scheduled meetings and meetings begin at 7:30. Details will be published on this website on how to join our meetings.

Our Amazing Moon

The video linked here is a recording of the presentation portion of the October 12, 2020 Zoom meeting of the Cuyahoga Astronomical Association (CAA). The presenter is CAA president William Murmann whose chief interest in astronomy is Earth’s own Moon. A brief question and answer exchange is included at the end of Murmann’s talk. This video, hosted at Vimeo, will eventually become unavailable.

October 12 monthly meeting takes place via Zoom

Because our regular meeting place is closed in accordance with COVID-19 restrictions, meetings of the Cuyahoga Astronomical Association (CAA) are taking place via the popular Zoom service.

The title of tonight’s talk is “Our Amazing Moon” presented by our local lunar expert Bill Murmann. He will discuss our nearest neighbor in space and the critical role it plays in our lives, and the possible role it may play in our future.

Here is how to attend the October 12 meeting via Zoom when “doors open” t 7:20 p.m. —

Either “Phone in” or watch and participate via “Zoom Video”.

Phone In: Just dial: 1-312-626-6799 (Chicago number)

You will be required to enter our Meeting Number: 987 496 1637


Zoom Video with video and audio, on your web browser. (No camera required) (No password to enter)

If you are tech-savvy, go to, you can download and install their app on your phone, tablet, or computer, then join our meeting using the Meeting Number given above.

Meeting Agenda

7:20 Meeting will be opened to everyone. (Socializing is welcomed!)

7:30 Opening Announcement will be made (All will be muted)

Introduction of President for commentary

Vice President will introduce our speaker for the evening

Speaker will ‘take the floor’. (No questions during the presentation)

Question & Answer session (Please be patient, it does take time to manipulate)

8:20 (ish) President calls the CAA Business Meeting to Order (All Muted)

At conclusion of the meeting, everyone is welcome to stay to socialize.

2020 Nobel Prize in Physics awarded for research on Milky Way’s supermassive black hole

The central parts of our Galaxy, the Milky Way, as observed in the near-infrared with the NACO instrument on ESO’s Very Large Telescope. By following the motions of the most central stars over more than 16 years, astronomers were able to determine the mass of the supermassive black hole that lurks there.
Credit:ESO/S. Gillessen et al.

Reinhard Genzel and Andrea Ghez have jointly been awarded the 2020 Nobel Prize in Physics for their work on the supermassive black hole, Sagittarius A*, at the center of our galaxy. Genzel, Director at the Max Planck Institute for Extraterrestrial Physics in Germany, and his team have conducted observations of Sagittarius A* for nearly 30 years using a fleet of instruments on European Southern Observatory (ESO) telescopes.

Genzel shares half of the prize with Ghez, a professor at the University of California, Los Angeles in the US, “for the discovery of a supermassive compact object at the center of our galaxy”, with the other half awarded to Roger Penrose, professor at the University of Oxford in the UK, “for the discovery that black hole formation is a robust prediction of the general theory of relativity.” 

“Congratulations to all three Nobel laureates! We are delighted that the research on the supermassive black hole at the center of our galaxy has been recognized with the 2020 Nobel Prize in Physics. We are proud that the telescopes ESO builds and operates at its observatories in Chile played a key role in this discovery,” says ESO’s Director General Xavier Barcons. “The work done by Reinhard Genzel with ESO telescopes and by Andrea Ghez with the Keck telescopes in Hawaii has enabled unprecedented insight into Sagittarius A*, which confirmed predictions of Einstein’s general relativity.”

ESO has worked in very close collaboration with Genzel and his group for around 30 years. Since the early 1990s, Genzel and his team, in cooperation with ESO, have developed instruments designed to track the orbits of stars in the Sagittarius A* region at the center of the Milky Way. 

They started their campaign in 1992 using the SHARP instrument on ESO’s New Technology Telescope (NTT) at the La Silla Observatory in Chile. The team later used extremely sensitive instruments on ESO’s Very Large Telescope (VLT) and the Very Large Telescope Interferometer at the Paranal Observatory, namely NACO, SINFONI and later GRAVITY, to continue their study of Sagittarius A. 

In 2008, after 16 years of tracking stars orbiting Sagittarius A*, the team delivered the best empirical evidence that a supermassive black hole exists at the center of our galaxy. Both Genzel’s and Ghez’s groups accurately traced the orbit of one star in particular, S2, which reached the closest distance to Sagittarius A* in May 2018. ESO undertook a number of developments and infrastructure upgrades in Paranal to enable accurate measurements of the position and velocity of S2.

The team led by Genzel found the light emitted by the star close to the supermassive black hole was stretched to longer wavelengths, an effect known as gravitational redshift, confirming for the first time Einstein’s general relativity near a supermassive black hole. Earlier this year, the team announced they had seen S2 ‘dance’ around the supermassive black hole, showing its orbit is shaped like a rosette, an effect called Schwarzschild precession that was predicted by Einstein.

Genzel and his team are also involved in the development of instruments that will be installed on ESO’s Extremely Large Telescope, currently under construction in Chile’s Atacama Desert, which will enable them to probe the environment even closer to the supermassive black hole.