Southern Maine Astronomers
Club Meeting
1 September, 2022 7:00 p.m.
Attending were members David Gay, Kevin, Kane, Russell Pinizzotto, Greg Thorup, Ron
Thompson, Greg Shanos, Jack Gelfand, David Manchester, John O’Donnell, Jon Wallace, Ted
Hebert, Chris Parent, Dana Hutchins, Carson Hanrahan, Alison Leonard, Kerry Kertes, Roy
Reigel, Forrest Sumner, Craig Snapp, Bob Ashton, Brad Irish, Earl Raymond, Anita Devito, John
Saucier, George Bokinsky, Nicholas Wall and Rob Burgess and guests Joe Glasik, Bob Harrison,
Frederic Pouille, Brian, and our speaker, Gary Golnik.
Club Updates:
Rob reported that since July six new members have joined the club taking membership to 86,
another record high. There has also been a surge in people joining Google Groups which now
has 99 participants, most of whom are not club members but simply individuals interested in
astronomy. Some of these GG members will eventually become club members, so it is good to
have a strong and growing participation in our discussion forum. Rob reminded SMA members
who are not on the Google Groups forum to sign up to stay engaged in various discussions and
postings within the club.
Since our last meeting the club has hosted two star parties at Neptune Drive and another in
Cumberland sponsored by the local library. The August 13 club star party was very well
attended with about 40 guests. Rob attributed this to finally getting the publicity process
figured out. Thanks to Maame Andoh for handling this so effectively. James Shields also led a
group of about 50 campers in an observing session at Bradbury Mountain State Park on July 22.
Reports from Club Members:
Russ Pinizzotto informed members that he had imaged a few more nebulae and clusters in the
Herschel 400 Catalog and has only about five left to observe. He and his wife recently were at
the upper end of the Bay of Fundy near Moncton, NB and witnessed a two foot tidal bore
running upstream, and amazing scene demonstrating the power of tides. Russ also reported on
a debate raging within the Astronomical League about their observing programs being
completed with the assistance of new automated devices, and whether or not those
observations should be given full credit. He’ll keep us informed. Dana Hutchins reported on a
program he attended at the Pioneer Works in Brooklyn, NY that was inspiring and amazing.
Carson Hanrahan attended the Maine State Star Party at Cobscook Bay State Park at the end of
August, along with Dwight Lanpher, and said the weather was great and he had not been under
such dark skies for years. The program and camaraderie were great, but dew was a challenge!
Announcements:
- Club Directors’ Meeting Wednesday, Sept. 21 at 7 pm via zoom. All members are welcome to attend.
- Club Star Party at Neptune Drive, Saturday, Sept 10, 7-9 pm. Ron Thompson will provide a talk and demonstration of “navigating the night sky.” As always, volunteers are needed to run or assist with telescopes and laser-pointer tours, manning a welcome table, and just assisting with set up and tear down. Many hands make light work! Please consider helping out and contact Rob if you can do so.
- Club Star Party with Maine’s First Ship at the Bath waterfront, Saturday, Sept. 24, 6-9 p.m. Nautically-themed star party focusing on navigational stars that would have been used to help the pinnace Virginia, perhaps the first ship built in North America by European settlers, make her maiden voyage back to England in 1607. Volunteers are also needed for this event which will be a different kind of star party and a real community event in Bath.
- Club Star Parties at Neptune Drive, October 6 and November 12, 7 -9 p.m.
- Club Star Party at Woodward Point, Brunswick, October 29, exact time TBD, with Maine Coast Heritage Trust.
Speaker and Presentation:
Rob introduced our speaker, Gary Golnik, now retired after 42 years in optical engineering, the
last 20 of which were as a leader in the optical systems of the James Webb Space Telescope.
Gary received his BS in Physics at Worcester Polytech and his MS in Optical Engineering at the
University of Rochester. For the twenty or so year preceding his work with NASA Gary worked
on a variety of government programs through the Department of Defense. Gary’s team
received the Robert H. Goddard Exceptional Achievement for Engineering Award from NASA,
and Gary was personally recognized with the NASA Exceptional Public Service Medal for his
work on JWST.
Gary explained that JWST followed the NASA Great Observatories program that featured
Hubble (visible), Spitzer (IR), Chandra (X-ray) and Compton (Gamma-ray). Its mission is
fourfold: to examine the first light of star formation, to explore exoplanets in greater detail, to
examine the assembly of galaxies and to examine the birth of stars and planets. Its primary
instrument is its NIRCam, examining these targets in the infrared. In order to function properly,
the telescope has to be shielded from the heat of the sun, Earth and Moon, utilizing a series of
sun shields as well as being located at Lagrange point 2, nearly a million miles from Earth. Even
in space, the sun-side of the shield would be in the hundreds of degrees Kelvin whereas the
shaded, operating side with the telescope would be at 45 degrees Kelvin. (The image
processors are even colder, being mechanically cooled, at 4.2 degrees K.)
The Hubble Deep Sky field in 1995 was an added impetus to the development of JWST when it
revealed that an area of sky thought to be devoid of anything was found to be swimming in
thousands of unseen galaxies.
There were many daunting challenges facing JWST. It would be the largest orbiting telescope
ever built, it would be the lightest (with a strong and thermally stable beryllium mirror surface,
98% of which was machined out in a honeycombed pattern for strength), it would be
deployable (foldable) so it could fit into testing chambers, C-5 transport airplanes, and the
Ariane 5 rocket faring), it would operate in extreme cold to capture faint IR signals, and there
was no fixing it – it needed to work perfectly the first time. It would hold two NIRCams for
redundancy. The telescope needed to be assembled under pristine cleanliness, a challenge in
that in the course of assembly and testing it was moved around the country to various testing
facilities. The slightest amount of dust on the mirrors could obscure its targets of the faintest
signals, and dust also reduced the reflectivity of the mirrors. They acuity of the mirrors was in
the 50 nanometer range with a human hair’s thickness representing 70,000 nanometers. Gary
said the mirrors were so thin that a simple piece of tape to hold a thermocouple to the back
side of the mirror for testing would measurably deform the mirror. Realities like this challenged
the engineers to develop whole new ways of testing the instrument.
Gary said that one of the reasons for Webb’s frequently criticized cost overruns and time delays
was the fact that so much of the designs for components, and testing, were being invented
from scratch which clearly takes time. Some of the testing for the telescope occurred in giant
cryo chambers used for the Apollo mission. This required the telescope to be frequently moved
from place to place around the country – no small feat. He said that once the instrument was
placed in the cryo chamber it took 30 days to cool it to the extremely low temperatures it
would face in space, giving the scientists about another 30 days to conduct their test. After
that, it took 30 days to bring the instrument back to room temperature.
Each of the 18 mirrors has its own actuators that can reposition the mirror and make
adjustments in its curvature. The actuators are slow to make adjustments. The mere act of
using them also creates heat that must be accounted for when adjustments are made.
Electronic systems had to be shared among various component users since weight and size
limitations prevented independent systems on the telescope. The mirrors were assembled in a
“folding table” design, with the outside mirrors folding flat against the telescope core like
leaves on a table, until deployed into one large 6.6 meter shape. The tolerances between these
mirrors when deployed were within 100 microns.
Gary explained the mirror alignment process that occurred this spring after the telescope was
at L2. It took two days for each test picture taken by each of the 18 mirrors. The first combined
image showed a random scattershot of dots. Eventually those dots were positioned into the
hexagonal configuration matching the actual mirrors and then focused in to form one image.
While some of the images show diffraction spikes caused by the telescope design, those are
eventually removed by software. Gary showed the latest images of Jupiter in IR light and the
Cartwheel Galaxy.
In answer to a question about the micrometeor hit on one of the mirrors Gary said it did not
create much of a problem. Small scale impacts can be adjusted for. The sturdy beryllium
structure also diffuses the effects of an impact, not allowing it to propagate as might happen
with glass. Actuators allow for minor adjustments. If the impact was bad enough the mirror
could be tilted out of the light path. The telescope’s capabilities would be diminished but not
destroyed. He stated that the space weather at L2 was reasonably understood although JWST
does keep track of developments in the Solar System that could affect operations. Gary said all
electronic cabling with any external exposure was shielded in aluminum to protect it from
micrometeorite impacts.
In response to another question about possibly refueling the telescope to extend its life Gary
stated there are no capabilities to do that. Designing in nozzles to accept refueling creates its
own set of unique problems that were outside of what the design team was prepared to
accept. He said the excellent launch by the French Ariane team put the telescope on an ideal
course for L2, saving lots of fuel. He also stated that because the weight of the telescope was
somewhat under budget they were able to add more fuel. Since the telescope is not movable
itself, the entire spacecraft needs to move with such maneuvers requiring fuel. At this point
they believe the telescope should operate for at least 10 years, twice its design specs.
Gary said how proud we should all be with the accomplishment of JWST team, involving 10,000
people, from 40 to 50 countries, with five major countries assisting in the project. This is a
project for all of humanity.
Tour of Globular Clusters:
To close off the meeting, Russ Pinizzotto led us on a tour of four of the smaller and more
obscure, but no less delightful, constellations high in the late summer sky: Equuleus (the Little
Horse), Delphinus (the Dolphin), Sagitta (the Arrow) and Vulpecula (the Fox). There were two
Messier objects among these constellations: M71 in Sagitta, the Starfish Cluster, a low density
globular cluster; and M27 in Vulpecula, the Dumbbell Nebula (aka the Applecore Nebula”), the
first planetary nebula discovered by Charles Messier in 1764. It also houses the largest known
white dwarf.
There are three Caldwell objects – C42 and C47, two beautiful globular clusters and C37, an
open cluster.
Notable NGC objects include NGC 7015 in Equuleus, a small, face-on classically shaped galaxy;
NGC 7045 – a nice double star in Equuleus; NGC 7013 – a spiral galaxy in Delphinus; NGC 6905 –
the Blue Flash Nebula (a planetary) in Delphinus; NGC 6891 – a very blue planetary in
Delphinus; NGC 6839 – an interesting asterism in Sagitta; PNG054.2.03.4 – a planetary nebula –
the Neckless Nebula, a stunning blue string of outburst rays; The Coathanger Asterism in
Vulpecula; and PSR 131919+21 Pulsar in Vulpecula – discovered in 1967, the first pulsar ever
discovered of now 3,000 pulsars, found by Jocelyn Bell Burnell. Ms. Bell discovered it as a
graduate student and her advisor, Anthony Hewish, got all the credit including a Nobel Prize.
She discovered a total of four pulsars. Eventually, the injustice of the lack of recognition for the
Nobel Prize was remedied with a $3 million award to her that she used to help under-
represented groups pursue astronomy careers.
October’s meeting tour: Lyra, Lacerta
Reported by:
Rob Burgess