From the Director

Rex
by Rex Parker, Phd director@princetonastronomy.org

Be thankful for computerized star charts We’ll illuminate the history of celestial cartography at our next meeting via Zoom on Nov 10 at 7:30 (see Ira’s section below about the guest speaker and Zoom link). The premise that we stand on the shoulders of giants is apropos here, as planetarium software today owes a great debt to the work that came before. Our computers can display a wealth of graphical information using very large databases created over the decades (actually, centuries) by professional astronomers. Astrometry is the oldest branch of astronomy largely because of its role in the development of navigation. Some experienced AAAP members will recall flipping through paper star atlases with flashlights in the dark beside our telescopes, trying to find dim celestial objects which were equally faint on the chart pages. Having a laptop PC, iPad, or cell phone display colorful, zoom-able, searchable star charts with million object catalogs is one of the many wonders of the modern era that we absolutely cannot live without!

AAAP astrovideo live – one Friday per month via Zoom A proposal for regular astro video sessions for members was described in last month’s Sidereal Times, and I urge you to go back and read it. The vitality of our astronomy club depends on audio/video technologies – these days we have few alternatives. AAAP intends to expand involvement in these areas and help members apply them in an astronomy context. The idea we’re developing is to offer members regular opportunities to participate in live astrovideo Zoom sessions. The events feature electronically-assisted astronomy (EAA) with local telescopes run by members. The stable of scopes sending live video to these sessions includes the club’s Paramount/Celestron-14 with ZWO-ASI-294 CMOS camera, along with 6 inch Astrophysics refractor, 12.5 inch AG Optical Cassegrain, and other scopes owned by members. Those of you who are gearing up to do EAA with your own equipment are welcome to be part of the video source, and all members are urged to join in the sessions to learn and enjoy. This is the beauty of using Zoom to host the sessions.

The once-a-month events are being scheduled, rain-or-shine, on the Friday nearest the new moon each month for best sky conditions. In clear weather live sky tours will be featured, while cloudy nights allow a forum for “how-to” discussions of the technology and astronomy talk. The first session was held on Oct 16, a cloudy night, and it was well-attended and much appreciated based on feedback. Starting times and Zoom links will be sent to members prior to each event.

Upcoming AAAP astro video sessions
Nov 13 Dec 11 Jan 15 Feb 12



Seeking the next Program Chair

You may have heard that Ira Polans intends to step down as Program Chair after December following a tremendous run of 5 years in the post (see his article below). The chair of the program committee is an officer of the Board of Trustees whom we elect each May. With Ira ready to hand it over soon, we need one of you to step up into this important role.

We’ve usually had a committee of one, but it doesn’t need to be that way, and in my opinion should not be so going forward. In fact the by-laws describe the role as follows. Section 1: Duties of the Officers. E. Program Chair. The Program Chair shall select a Program Committee, over which the chair shall preside. The Program Committee shall be responsible for arranging suitable astronomy-related programs at general meetings.

Our club runs on the energy released by the speaker program, with the Princeton cachet as an additional fuel source. We have connected with amazing speakers over the past many years, and undoubtedly Princeton has been a draw for getting top notch speakers. Coming to campus, having AAAP-hosted dinner in town, and presenting in the auditorium of the famed Dept of Astrophysical Sciences is a potent venue for speakers. Now we are deep in the new era of remote Zoom meetings. While much seems lost, for a while at least, there are also positive aspects. There is the unique opportunity to connect with world-class scientists, authors, and innovators unencumbered by distance and travel expenses. The next program chair can contact potential speakers across the globe using the club’s “program@princetonastronomy.org” e-mail address. It’s a chance to directly communicate and develop rapport with professional and amateur astronomers, scientists, and other experts. The office empowers the Chair with the obligation to make the Princeton connection with these potential speakers, who nearly always are pleased to receive the invite even if they are not always able to say yes. Princeton provides the entrée into places and personalities that many other clubs may not have.

It’s been fantastic for me to work with Ira over the past 5 years. He’s done the job at a very high level with innovation and creativity. He’s carried out the role with deep consideration of appropriate topics and identified and coaxed important astronomers to speak to us at our monthly meetings. We’ve had some of the best speaker presentations ever in the history of AAAP during these 5 years. Please contact me soon if you are interested. And I will help you form the committee so you’re not going it alone.

Posted in November 2020, Sidereal Times | Tagged , | Leave a comment

From the Program Director

by Ira Polans

The November meeting will be held on the 10th at 7:30 PM. (See Joining the Meeting with Zoom below for details). This meeting is open to AAAP members and the general public. Due to the number of possible attendees, we will use the Waiting Room. This means when you login into Zoom you will not be taken directly to the meeting. The waiting room will be opened at 7:00 PM. Prior to the meeting start time (7:30 PM) you may socialize with others in the waiting room. The meeting room has a capacity of 100 people.

For the Q&A session, you may ask your question using chat or 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.

Meeting Event Participant Can Speak? Participant Can Self-Unmute?
Rex’ General Remarks Yes Yes
Ira’s  Speaker Introduction Yes Yes
Speaker Presentation No No
Q&A Session Start All on Mute Yes
Business Meeting Start All on Mute Yes

Only the Business part of the meeting will be locked.

Featured Speaker: Amateur astronomer Nick Kanas, MD will give a talk on Celestial Mapping and the Modern Amateur Astronomer. The history of celestial cartography has evolved into several pathways that have relevance for today’s amateur astronomer. Ancient views of the sky had star mapping traditions that used both a geocentric orientation (where the stars and constellations were pictured as they were seen from the Earth) and an external orientation (where they were right to left reversed as seen from the outside of a celestial globe carved in marble). The development of the telescope favored a geocentric view, as well as a switch in the celestial grid from a longitude/latitude perspective to one that spoke about right ascension/declination. Many ancient books included volvelles, analog computers on paper that attempted to reproduce some of the features of 3-dimensional astrolabes on 2-dimensional pages in a book. These led to our modern planispheres. Early atlases pictured beautiful images of mythological and scientific figures in over 100 constellations, but these were reduced in number by an international society to 88 constellation areas of the sky, with increasingly fading then non-existent constellation images (but whose line drawings persist in modern astronomy magazines). Dr. Kanas will trace the history of these and other developments that we take for granted as amateur astronomers.

Speaker’s Biography: Nick Kanas has been a member of the SFAA since 1977, serving as a Board member in the early 1980s. He has been an amateur astronomer since childhood. He is a Fellow of the Royal Astronomical Society (London). He has collected antiquarian celestial maps for over 40 years and has given talks on celestial cartography to amateur and professional groups, including the Adler Planetarium; the Lick Observatory; the California Academy of Sciences; and annual meetings of the International Conference on the History of Cartography, the Society for the History of Astronomy, and the Flamsteed Astronomical Society in Greenwich, U.K. He has published articles on celestial cartography in magazines and journals, such as Sky and Telescope, Imago Mundi, and the Journal of the International Map Collectors Society. He has written two celestial map-related books: Solar System Maps: From Antiquity to the Space Age, and Star Maps: History, Artistry, and Cartography, the 3rd edition of which was published in 2019. He also has published three science fiction novels. As a UCSF Professor of Psychiatry, he was a NASA-funded Principal Investigator studying psychosocial issues involving astronauts and cosmonauts in space. He is the co-author of the textbook Space Psychology and Psychiatry (now in its 2nd edition), and more recently the author of Humans in Space: The Psychological Hurdles. Both books were award Life Science Book Awards from the International Academy of Astronautics.

Using Zoom: While we are, social distancing the AAAP Board has chosen to use Zoom for our meetings, based our belief that many members have already have used Zoom and its ease of learning. 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.

How to Join the November Meeting: For the meeting, we are going to follow a simple two-step process:

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

NOTE: We plan to open the meeting site 30 minutes to the 7:30 start time. This way you won’t have to rush to join the meeting. A maximum of 100 attendees can join the meeting.

More Information: The Zoom site has many training videos most are for people who are hosting a meeting. 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.

Journal Club Presentation: Rafael C. Caruso will present on Sir Arthur Eddington’s observations of the 1919 solar eclipse, which supported the predictions of the general theory of relativity. His presentation is based on a chapter from the book Gravity’s Century: From Einstein’s Eclipse to Images of Black Holes by Ron Cowen (Harvard University Press, 2019).

We are looking for other members to give a Journal Club Presentation. If interested, please contact either director@princetonastronomy.org or program@princestonastronomy.org.

Program Chair: As announced at the October meeting I am resigning as Program Chair effective December 31, 2020. When I started, I figured I would do the job for a year or two. I ended up serving for 5 plus years. Now I think it is time for somebody else to take on this role. If you’re thinking about becoming the Program Chair, you have the unique opportunity to test drive the role for 3-4 months before deciding if you want to continue on for a full-term. As Program Chair, under our by-laws, you can establish a Program Committee to help choose topics and speakers so you don’t have to go it on your own. The committee could decide to rotate the formal position of Program Chair among its members from year-to-year. This way no one is making a long-term commitment.

As Program Chair you will have the final word on the topics you, think the club will be interested in hearing or learning about with the support of the Program Committee. You also will have the opportunity to interact with professional astronomers and authors as you fill the schedule. While serving as Program Chair I learned that most astronomers are very happy to give a talk to our club. The fact that the Princeton University Astrophysics department hosts us is a draw to potential speakers.

In addition, we have a ready-made pool of speakers in the area. This includes Princeton, Philadelphia, New York, and Eastern Pennsylvania. We also have Zoom. This means that potential speakers don’t have to travel to NJ to give their talks. This month’s featured speaker will be giving his talk from California. While I will not be scheduling speakers past December, I’ve offered to help with the transition and provide advice to the new Program Chair. As of next year, I will be a regular member of the AAAP. To keep things on track, ideally somebody will step up at our November club meeting to be the next Program Chair.

Posted in November 2020, Sidereal Times | Tagged , , | Leave a comment

Minutes of the October 6, 2020 AAAP Board of Trustees meeting (virtual)

by John Miller, Secretary

● Rex Parker opened the Zoom meeting at 7:00 P.M.

● Rex and David Skitt indicated that the previous plan of opening the Washington Crossing Observatory to six people inside the building had failed to consistently succeed in keeping individuals at the required “social distancing” spacing of six feet (Covid-19 safety rules). Control of people into the observatory, it was reported, proved difficult to manage.

● Rex suggested modifying his “Phase 2” Observatory Re-Opening Plan. It was proposed a “Phase 1.5” ad-hoc change be adopted in the interim. This adjustment to the original “Phase 2.0” plan would:
1. Raise the guest number from 16 to 20 (6 inside; 14 outside from the original 6 inside 10 outside).
2. Assign a AAAP key holder to monitor/control the number of people entering the observatory.
3. Allow only AAAP members and their families to attend (“Phase 2.0” would allow the public in limited numbers). Mask-wearing, hand sanitizer and “social distancing” would continue to be enforced.

● Secretary John Miller called for a Board vote to adopt the interim “Phase 1.5.” The vote was:
Rex Parker, Director Yea;
Larry Kane, Assistant Director Yea;
Michael Mitrano, Treasurer Yea;
John Miller, Secretary Nay;
Ira Polans, Program Chair, (in absentia per Rex Parker), Yea.
The motion was passed 4 to 1.. .

● Bill Murray, current AAAP representative to the United Astronomy Clubs of NJ (UACNJ), mentioned he was named a nominee by the UACNJ as a candidate for the UACNJ liaison to the member clubs. Should he gain this position, he would have to relinquish his representative status (to the UACNJ) at the AAAP.

● Additional suggestions were made by Observatory Chair David Skitt to use our EAA (Electronically Assisted Astronomy) set up at the observatory to live-stream images to members online and on screens mounted on the outside of the WC Observatory.

Posted in November 2020, Sidereal Times | Tagged , , , | Leave a comment

Robert Vanderbei’s Mars Photo

Bob Vanderbei is a professor in the Department of Operations Research and Financial Engineering at Princeton University. He is an amazing astro-photographer and a club member.  His photo of Mars below taken at 3:15 a.m. on October 6 makes you want to visit the planet and perhaps make a stop at the resort on its southern tip! 

  • Bob’s telescope is a 4” f/5 Takahashi FSQ-106 refractor.
  • He uses it for imaging when the desired field of view is too large for his 10” RC. I does not use it as a guide scope.
  • The mount is a Takahashi NJP Temma-II equatorial mount.
  • His current astro-specfic camera is a StarlightXpress Trius SX-694 CCD camera.  
  • It’s not a color camera and that’s why he has a filter wheel.
  • https://vanderbei.princeton.edu/

Posted in November 2020, Sidereal Times | Tagged , , | Leave a comment

Mars Opposition Photos from the Past

by John Church


Left Picture: August 18, 1971         Right Picture: Oct. 11, 1973
Edmund 4-inch refractor            Hastings-Byrne 6¼ inch refractor
Angular diameter 24.7 arcsec           Angular diameter 21.4 arcsec
Central Meridian 10º              Central Meridian 328º
                       Published in Sky & Telescope, March 1979

Back in the 1970’s I did not have today’s superb electronics, charge-coupled devices, and so on. All I had was fine-grain film, a home darkroom, and advice about special developing techniques from an advanced amateur photographer and a professional at work. Plus some good refractors. I still have my Edmund 4-inch which I occasionally use at home. I was lucky to have had custody of our fine Hastings-Byrne refractor from 1972 until it was installed at our Washington Crossing observatory soon after we had finished building it in the late 1970s.

Mars is a superb object at a good opposition when there isn’t a major dust storm, such as the one two years ago. We are having an excellent view at present and many surface features are visible. In my August 1971 photo, the prominent feature Syrtis Major had just rotated out of view to the east. Mare Serpentis extends upwards towards the south polar cap. Sinus Meridiani, at 0 degrees Martian longitude, had rotated slightly east of center. The south polar cap is prominent. The extensive dark area to the upper right is Mare Erythraeum.

In my October 1973 photo, Syrtis Major is the large dark area, with Mare Serpentis again extending upwards to the right. Sinus Meridiani is the rightmost small dark area. The south polar cap has shrunk considerably with the advance of summer in Mars’ southern hemisphere. We can also see a small change in the apparent tilt of Mars as seen from Earth. At the present opposition, the south polar cap is also quite small but still readily visible in our telescopes at the observatory.

Technology has advanced tremendously since the age of film. Our talented club astrophotographers are producing wonderful images of Mars and other objects with their fine equipment and techniques. I look forward every month to seeing the results of their extraordinary work in the pages of Sidereal Times.

Posted in November 2020, Sidereal Times | Tagged , | Leave a comment

Super Nova 2020SSF in NCG7722 – EAA With The AAAP C14

by Tom Swords

For the October 3rd AAAP members observatory night, one of the target suggestions on my list was for a recently discovered SuperNova I had read about on Cloudy Nights.

The previous night I had attempted to capture an image of SN 2020ssf from my backyard with a 5.5” APO refractor and ASI385 camera with no success. Perhaps the C14 and camera could?

It was the end of the evening, we were winding down observing and I remembered that we had not attempted this target yet. I asked Dave Skitt if he wanted to try for it and he agreed to.

So off to NGC7722 in Pegasus we went. NGC7722 is a spiral galaxy at mag 13.4 and 2.1 X 1.6 Arc minutes in size. Small and dim even for the C14 at F6.3.

DSS image of NGC7722 from Sky Safari

I wasn’t expecting we would see much. The slew stopped and we saw nothing but a few brighter field stars in the preview window. Dave began the stacking process and increasing exposure. And there it was! Well at least we hoped it was what we though it was.

A few days later I saw an image of the Super Nova from these folks at the Virtual Telescope Project 2.0, they provide the information about the equipment and exposure used to capture the image.

AAAP C14 at F6.3 Color image, imaged October 3rd, 2020
Same approximate area, note the same stars are in the FOV, just a bit bigger in scale.

Dave later gave me a copy of the images that were captured with the C14. I thought to confirm that we had indeed captured an image of the Super Nova by comparing our image to the one provided by the virtual telescope team. I examined the two images, did some cropping to get the imaged area to be similar in FOV with identical field stars and the C14 definitely got it!

Virtual Telescope Project 17’ Plane Wave at F6.8, Monochrome image, imaged Oct 8th, 2020

I actually prefer our image in color because you can see that the nova is a brighter white than the surrounding galaxy.

This is a fun and rewarding part of being active with EAA. Engaging a reported new target, attempting to get an image and we did!

Posted in November 2020, Sidereal Times | Tagged , , | Leave a comment

Symphony of the Stars

by Samuel Sherman

Asteroseismology is the use of sounds produced by the Sun and other stars to expand our knowledge of the physical traits and characteristics of stars and better understand our Sun. From the stellar sound we can learn about “the effective temperature, density, mass, age, and metallicity of stars.” Stars are three-dimensional, so their natural oscillation modes have nodes in three orthogonal directions. Those nodes are “concentric radial shells, lines of latitude, and lines of longitude in a spherical coordinate system.”

Kepler Space Telescope, Model 2 – NASA

From data collected by Kepler, K2, and in the future, TESS, we can translate the subtle pulsation of stars mathematically into a view of the number of modes and the displacement of each. After this is done, it is easy to determine the location of nodes on and within a star. Once this is determined, for modes that are not directed at the center of the star (nonradial modes) the lower part of the wave is in a higher temperature environment than the upper part of the wave. This means that it is in a region of higher sound speed. As a result the wave is refracted back to the surface, where it is reflected, because acoustic energy is trapped in the star. The location of this refraction can be predicted mathematically as a function of temperature. This means that we can probe the interior of our Sun and all stars where we perceive these modes.

Nicolaus Copernicus -National Geographic

None of this data could be collected without the development of Copernican Heliocentric theory. This theory was published by Nicholas Copernicus, a Polish mathematician and astronomer, in 1543. His theory was important to Asteroseismology in multiple ways, but the largest was that it gave way to centuries of great minds seeking to correct errors he had made with his original theory. One of the most famous examples of someone who changed his theory was Kepler, who found the oscillation of the Suns and planets. Measuring the oscillations of the Sun is the basis from which the study of Helioseismology, a study closely linked to Asteroseismology, comes. Although it may seem obvious today, Copernican Heliocentricity put the Sun much closer to the Earth than any other star, making it ideal for studying the characteristics of stars. The understanding of the Sun being much closer to Earth than any other star is the basis understanding the Solar-Stellar Connection. The Solar-Stellar Connection explains the connection between the immensely more detailed collection of data we can collect about the Sun over any other star and how we can compare the data from the Sun to other stars to better place the information of our Sun into the proper context.

To collect the data needed to piece together the Solar-Stellar Connection, we have launched missions into space. The current data has come from the Kepler and K2 missions. Kepler was launched in March 2009 to “determine the percentage of terrestrial and larger planets that are in or near the habitable zone of a wide variety of stars and to discover the variety of orbit size and planet reflectivities, sizes, masses, and densities of short-period giant planets.” It was also sent to determine the properties of the stars that harbor planetary systems. By using data primarily for exoplanet transit detection, asteroseismologists were able to “infer the influence of stellar pulsations from companion stars.”

Transiting Exoplanet Survey Satellite (TESS) – NASA

Our data is limited to stars with solar-like oscillators, stars with convective zones, such as cool main-sequence stars, subgiants, and red giants (this does not include stars with surface radiative zones, as they behave very differently). If we know the mass and radius, we can easily find the star’s density, which can tell us about the star’s composition. These patterns help us situate stars on an HR diagram more accurately, and thus infer much about the age and metallicity of the star. It is important to note that the field of asteroseismology is in “its relative infancy.” Therefore, it will develop and evolve over time. The data that will be collected from TESS promises many more discoveries that will help develop our understanding of the Solar-Stellar Connection.

By Samuel Sherman[1], Kelly Al-Dakkak[1], Ashley Nalley[1], Rosanne Di Stefano[1, 2]
1. Dept of Astronomy, Harvard University, Cambridge, MA
2. Professor in the Department of Astronomy. rdistefano@cfa.harvard.edu

Posted in November 2020, Sidereal Times | Tagged , , | Leave a comment

Snippets

compiled by Arlene & David Kaplan

-NYT

-NYT

-BBC

 Sir Roger Penrose: The man who proved black holes weren’t ‘impossible’  If you ever struggled with maths at school, you were in good company. Sir Roger Penrose, who on Tuesday won the Nobel Prize for Physics, would also scratch his head in class. “I was always very slow. I was good at maths, yes, but I didn’t necessarily do very well in my tests,” the Colchester-born (1931) laureate recalled….more

-BBC

Planet Mars is at its ‘biggest and brightest’   Mars is at its biggest and brightest right now as the Red Planet lines up with Earth on the same side of the Sun. Every 26 months, the pair take up this arrangement, moving close together, before then diverging again on their separate orbits around our star…more

-BBC

 Black hole breakthroughs win Nobel physics prize   Three scientists have been awarded the 2020 Nobel Prize in Physics for work to understand black holes. Sir Roger Penrose, Reinhard Genzel and Andrea Ghez were announced as this year’s winners at a news conference in Stockholm. David Haviland, chair of the physics prize committee, said this year’s award “celebrates one of the most exotic objects in the Universe”…more

-NYT

-NASA

Life on Earth: Why we may have the moon’s now defunct magnetic field to thank for it  The habitability of a planet depends on many factors. One is the existence of a strong and long-lived magnetic field. These fields are generated thousands of kilometres below the planet’s surface in its liquid core and extend far into space – shielding the atmosphere from harmful solar radiation….more

-ALMA (ESO/NAOJ/NRAO)

Volcanoes fuel gaseous atmosphere on Jupiter’s moon Io  What is creating the bubbling, gaseous atmosphere on Jupiter’s moon Io? Scientists think they finally have the answer: volcanoes. Io, the solar system’s most volcanically active world, is one of four Galilean moons — the four largest moons of Jupiter, which were discovered by Galileo in the 17th century — and one of 79 total known satellites around the planet…more

-Rodriguez et al

The first habitable-zone, Earth-sized planet discovered with exoplanet survey spacecraft   TESS, the Transiting Exoplanet Survey Satellite, was launched in 2018 with the goal of discovering small planets around the Sun’s nearest neighbors, stars bright enough to allow for follow-up characterizations of their planets’ masses and atmospheres. TESS has so far discovered seventeen small planets around eleven nearby stars that are M dwarfs….more

Water On The Moon Confirmed, And There May Be Much More Than We Thought  NASA’s intriguing announcement last week that it would reveal an “exciting discovery about the Moon” led to a lot of speculation on what this big discovery might be. We can now all share in the excitement of the space agency: the Moon appears to have a lot of water, and this could make future exploration of our natural satellite much easier…more

-NASA

Water on the Moon could sustain a lunar base Having dropped tantalising hints days ago about an “exciting new discovery about the Moon“, the US space agency has revealed conclusive evidence of water on our only natural satellite. This “unambiguous detection of molecular water” will boost Nasa’s hopes of establishing a lunar base. The aim is to sustain that base by tapping into the Moon’s natural resources…more

-NASA

American astronaut casts vote in space for US elections  Nasa astronaut Kate Rubins voted from the International Space Station last week for the US presidential elections. Rubins, the only American astronaut currently in space, is on a 6-month-long mission. Read on to know how an astronaut votes from space…more

Posted in November 2020, Sidereal Times | Tagged , | Leave a comment