National Capital Astronomers

About NCA

Founded in 1937 at the US Naval Observatory by a group of professional and amateur astronomers, the National Capital Astronomers (NCA) is a volunteer-driven nonprofit aiming to ignite public interest in astronomy and space science. We're all about sharing the wonders of the universe with everyone!

Our Stellar Activities:

Our Cosmic Perspective:

While we marvel at the discovery of thousands of exoplanets, we recognize Earth's unique hospitality. This drives our mission to protect our planet's resources and life. After all, as Captain Kirk (a.k.a. William Shatner) discovered, space is a harsh place!

Join us for a cosmic journey and be part of our mission to explore, understand, and protect our universe!

Our Meetings

Monthly Meetings with Educational Presentations are Free and Open to the Public

NCA has regular monthly meetings September through June on the second Saturday of the month. For 2025-26, meetings will be held in-person at the University of Maryland Astronomical Observatory in College Park, Maryland (directions/map) AND online via Zoom (details below). Seating is limited, so we are encouraging folks to attend via Zoom.

Public transportation: Directions/maps to the UMD Observatory

Inclement weather: In case of severe weather (tornado/snow/impassable roads), a notice will be placed on the Observatory Website on the day of the meeting. (Be sure to refresh/reload the page to make sure you are seeing an updated page.)

The meetings for this year will be HYBRID (online via Zoom AND in-person), unless otherwise noted!

Meeting Schedule for 2026-2027

With permission of the speakers, most meetings will be recorded. Once available the audio and video will be linked.

Online Meeting Information

National Capital Astronomers will be holding its 2025-2026 meetings online via Zoom and in-person. This year, the Zoom meetings have been set up so that there is no registration required. This is the direct Zoom link, it is the same for everybody for every meeting this year. If we have problems with Zoom bombing at a meeting, then the link will be canceled and a new one created that will require registration for subsequent meetings.
As usual, the Zoom room "doors" open at 7pm ET with the actual meeting starting on time at 7:30pm! While you do not need to sign in right at 7pm, please do not wait until 7:35pm!! And since we are not registering folks, it will be important that you have a recognizable name showing so that I can let you in from the virtual waiting room.

With the permission of the guestspeakers, we will be recording the meetings.

Zoom Link

Join Zoom Meeting: NCA Monthly Zoom

Zoom Etiquette

These guidelines will be updated as needed.

Models of the Universe (what we can and cannot know, what do we know, how and when did we know it?)

Dr. James B. Cole (Leidos)

Next Meeting Date: Saturday, 10 October 2026

7:30 pm

Abstract: How can we infer the shape and structure of the universe? How much confidence do we have in our deductions about the greater part of the Universe which we cannot access?
"The miracle of the appropriateness of the language of mathematics to the formulation of the laws of physics is a wonderful gift, which we neither understand nor deserve," thus remarked Eugene Wigner, one of the greatest physicist / mathematicians of the 20 th Century (contributions to fundamental science on a par with Einstein).
Models too can have almost mystical powers. Quarks were first considered a convenient fiction to explain the multiplicity of subatomic particles, but they turned out to be real. Except for the infinitesimal fraction of the Universe, which we can directly access, our understanding is through models based on observations and inference following the laws of logic and mathematics, constrained by the almost miraculous efficacy of Occam's razor.
We briefly review the historical stepping stones to our current understanding from the philosophy of Anaximander, on through the models of Ptolemy, Copernicus, and Kepler; and finally the Big Bang.
How can we infer the shape and structure of the universe? We delve into a few technical details: How do we measure the size of stars and their distances; what do we (think) we know about how stars evolve and the Big Bang?

Bio: I began my professional career at the University of Maryland (PhD, particle physics). I became interested in the structure of the Universe as a teaching assistant in the Astronomy Dept. We taught some of pioneering methodologies of Henrietta Leavitt in the classes. I was awarded a National Research Council post-doctoral fellowship at the NASA-Goddard Space Flight Center. A NASA balloon experiment that had detected antiprotons in the cosmic rays. Many exotic theories about their origin were extant: arrivals from an antimatter galaxy, decay of exotic particles, etc. My branch chief supported a more prosaic explanation: high energy (ordinary) protons interacting with ordinary matter in the upper atmosphere. We proved this via detailed simulations and modeling of the experimental instrumentation, which incorporated the known high energy proton flux, and antiproton production cross sections 1 . I realised that the extraction of information from noisy and imperfect data 2 , based on physical models is common denominator of basic science.
I transitioned to the US Naval Research Laboratory, where I developed models and algorithms to simulate wave propagation in complicated environments. This initiated my career in computational physics. I led and managed a joint research project 3 funded by Rohm and Hass Corp. to apply my algorithms to their industrial optics problems 4 .
A chance encounter with a member of a DARPA team that was planning to visit research laboratories in Japan. I causally mentioned that I speak technical Japanese, and was invited to join the team. After the tour I was invited by the NTT Basic Research Laboratory (Japan) as a visiting professor. where I gave seminars on Lie group theory and worked with the brain research group to model early vision 5 . We also examined the "invariance problem" in pattern recognition for industrial robot vision 6 .
Later I transitioned to the University of Tsukuba in Japan (tenured professor), and pioneered a new high-precision methodology for computational photonic, optics and quantum science 7 .
After more than twenty years in Japan I returned to the US on a senior research fellowship sponsored by Air Force Institute of Technology as a visiting professor, funded by the National Academy of Sciences, where I investigated Bayesian machine learning methodologies 8, 9 .
Lately I am a corporate scientist, working in quantum science and photonics research.
 
1 J. B. Cole, J. F. Ormes, The low energy atmospheric antiproton albedo, AIP Conf. Proc. 183, 386-387, https://doi.org/10.1063/1.38002.
2 J. B. Cole, The Statistical Mechanics of Image Recovery and Pattern Recognition, American Journal of Physics, vol. 59, no. 9, pp. 839-842 (1991).
3 CRADA between NRL and Rohm & Haas Co., Title: Computational Approach to Mie Scattering, NRL number: NCRADA-NRL-95-090.
4 S. A. Palkar, N. P. Ryde, M. R. Schure, N. Gupta, J. B. Cole, Finite Difference Time Domain Computation of Light Scattering by Multiple Colloidal Particles, Langumir, vol. 14, no. 13, pp. 3484-3492 (June, 1998).
5 S. Naito, J. B. Cole, "The Gravity Lens Illusion and its Mathematical Model," Chapter 3, pp. 3950, in "Contributions to Mathematical Psychology," G.H. Fischer, and D. Laming, editors (Springer Verlag, 1994).
6 J. B. Cole, S. Naito, A Lie Group Theoretic Approach to the Invariance Problem in Feature Extraction and Object Recognition, Pattern Recognition Letters, vol.12, pp. 519-523 (1991).
7 J. B. Cole, and S. Banerjee, "Computing the Flow of Light, Nonstandard FDTD for Photonics Design," SPIE Press, 2017 https://spie.org/Publications/Book/2250613?SSO=1
8 J. B. Cole, B. V. Egner, et al, Unsupervised Probability Density Expectation Maximization Algorithm for Particle Identification in Pulse-Shape Discrimination Applications, SORMA West 2021 Session PS 02-21, https://sormawest.org/poster-session-ps-02/
9 R. J. Olesen, J. B. Cole, et al., Regenerative neural network for rotating scatter mask radiation imaging, https://www.sciencedirect.com/science/article/abs/pii/S1350448721000780, (R.J. Oleson PhD dissertation).

Weather-permitting, there will be observing through the telescopes after the meeting for members and guests.

Telescope-Making and Mirror-Grinding

The telescope making, maintenance, and modification workshop with Guy Brandenburg is held in the basement (wood shop) of the Chevy Chase Community Center which is located at the intersection of McKinley Street and Connecticut Avenue, NW, a few blocks inside the DC boundary, on the northeast corner of the intersection. The workshop is open on Tuesdays & Fridays, from 6:00 to 9:00 PM. For information visit Guy's Website. To contact Guy, call 202-262-4274 or Email Guy!

Come See the Stars at Exploring the Sky 2026!

Exploring the Sky is a joint program between the National Capital Astronomers and the National Park Service Rock Creek Park Nature Center and has been run since 1948 at this location, the field at the corner of Glover and Military Roads in the District. There is an adjacent parking lot. It is free and all are welcome who have an interest in observing the heavens. It's not an ideal dark sky location but we can still see solar system objects (even the occasional comet), open and globular clusters and maybe a fuzzy galaxy or two.

Questions? Call NCA at 202-262-4274 and leave a message.

Download the 2026 flier

Date Time Things of interest
18 Apr 8:00pm M45, Orion, Jupiter
16 May 9:00pm M44, Leo, Arcturus, M13, Moon, Jupiter
20 Jun 9:00pm Leo, Bootes, Hercules, M13, Moon, Venus, Beehive
18 Jul 9:00pm Moon, Hercules, M13, Summer Triangle, Venus
15 Aug 8:30pm Moon, Hercules, M13, Summer Triangle, M57, M31, Venus
19 Sep 8:00pm Moon, Summer Triangle, Great Square of Pegasus, M31
17 Oct 7:30pm Summer Triangle, Moon, Great Square of Pegasus, M31, Saturn
07 Nov 7:00pm Summer Triangle, Pegasus, M31, Saturn, Moon
Exploring the Sky is a presentation of the National Park Service and National Capital Astronomers.

For NCA information by E-mail or phone

NCA Documents