Orange County Astronomers

Online Beginner's Class
2026-04-03 19:00 - 21:00, 2026-10-02 19:00 - 21:00 (America/Los_Angeles) | Online
This is a free and open to the public online event, to attend please register with zoom by clicking here at or after 6:40pm.
The 2nd session of the Beginners Astronomy Class covers the different types of equipment used to observe the night sky, including telescopes, mounts, eyepieces, filters, and advantages and disadvantages of different options.
This session is a must if thinking about buying a telescope.
For details, please visit here and download the sample information PDF package.
Views: 42

General Meeting - April 2026
2026-04-10 19:30 - 21:30 | Irvine Lecture Hall of the Chapman University, 336 N Center St, Orange, CA, 92866, United States
Join Zoom

Free and open to the public but per our host’s policy, minors (under 18) are welcome to attend as long as they are accompanied by their parent or guardian at all times.
This meeting’s speaker will present online.

Supernovae, Dark Energy, and the

Mystery of the Accelerating Universe

Type Ia supernovae are brilliant explosions of white dwarf stars and are some of the most powerful tools for measuring the universe. By comparing how bright these supernovae appear to how bright they really are, astronomers can measure distances across billions of light-years. In the late 1990s, these measurements led to one of the most surprising discoveries in the history of science: the expansion of the universe is speeding up, driven by a mysterious phenomenon that was named dark energy.
In this talk, we will explore how supernova discoveries (including contributions from dedicated amateur astronomers) feed into modern cosmological measurements. Along the way, we’ll see how today’s observations are deepening the mystery of dark energy rather than closing the case. The accelerating universe remains one of the biggest puzzles in physics and supernovae are still lighting the way toward the answer.

David Rubin is an Associate Professor of Physics and Astronomy at the University of Hawai‘i at Mānoa. His research focuses on using exploding stars called Type Ia supernovae to measure the expansion history of the universe and understand the nature of dark energy. He works on survey design, calibration, and statistical methods for current and next-generation observatories, including the Nancy Grace Roman Space Telescope.
Dr. Rubin received his Ph.D. in physics from the University of California, Berkeley working with Saul Perlmutter. He is still a member of the Supernova Cosmology Project and has authored or co-authored numerous publications on supernova cosmology and the accelerating universe.
Views: 42

OCA Astrophysics SIG Meeting
2026-04-17 19:00 - 22:00, 2026-05-15 19:00 - 22:00, 2026-07-17 19:00 - 22:00, 2026-08-21 19:00 - 22:00, 2026-09-18 19:00 - 22:00 | Orange Coast College, Building 40, Astronomy House, Merrimac Way, Costa Mesa, CA, 92626, United States
The monthly meeting of the Astrophysics Special Interest Group is at 7:00 PM every third Friday of the month at Orange Coast College, Building 40, Astronomy House. Please contact the ASIG chair for details at mark@ocastronomers.org .
Views: 42

Anza Star Party
2026-04-18, 2026-05-16, 2026-06-13, 2026-08-08, 2026-08-15, 2026-09-12, 2026-10-10 | On the Sky, CA, United States
The new moon weekend for the monthly star party. The Anza site is open to members and their guests only. Join other members for viewing and imaging. Contact any board member if you have any questions.
Views: 42

Online Beginner's Class
2026-05-01 19:00 - 21:00 | Online
This is a free and open to the public online event, to attend please register with zoom by clicking here at or after 6:40pm.
The 3rd session of the Beginners Astronomy Class covers different methods of finding objects in the night sky. Special topic is learning the constellations.
For details, please visit here and download the sample information PDF package.
Views: 42

General Meeting - May 2026
2026-05-08 19:30 - 21:30 | Irvine Lecture Hall of the Chapman University, 336 N Center St, Orange, CA, 92866, United States
Join Zoom

Free and open to the public but per our host’s policy, minors (under 18) are welcome to attend as long as they are accompanied by their parent or guardian at all times.
This meeting’s speaker will present online.

Early galaxies and infant black holes

in the primeval Universe

Finding and understanding the nature of the first stars at cosmic dawn is one of the most important and most ambitious goals for modern astrophysics. The first populations of stars produced the first chemical elements heavier than helium and formed the first, small protogalaxies, which then evolved, across the cosmic epoch, into the large and mature galaxies, such as the Milky Way and those in our local neighbour. Equally important and equally challenging is the search, in the early Universe, of the seeds of the first population of black holes, which later evolved in the supermassive black holes at the centre of galaxies, with masses even exceeding a billion times the mass of the Sun. When matter accretes on such supermassive black holes it can become so luminous to vastly outshine the light emitted by all stars in their host galaxy.

Since its launch, about two years ago, the James Webb Space Telescope has been revolutionizing this area of research. Its sensitivity in detecting infrared light from the remotest parts of the Universe is orders of magnitude higher than any previous observatory, an historical leap in astronomy and, more broadly, in science. I will presents some of the extraordinary discoveries from the Webb telescope, which have resulted in several unexpected findings. I will also discuss the new puzzles and areas of investigation that have been opened by Webb’s observations, how these challenge theoretical models, and the prospects of further progress in the coming years.

Roberto Maiolino is Professor of Experimental Astrophysics in the Department of Physics and at the Kavli Institute for Cosmology, University of Cambridge. He is also an Honorary Professor at University College London and a Royal Society Research Professor.
He has served as Director of the Kavli Institute for Cosmology, Cambridge, and is a Fellow of the Royal Society. He was knighted by the President of Italy in the Order of the Star of Italy and was awarded the Blaauw Honorary Professorship at the University of Groningen.
His research focuses on the formation of galaxies and black holes, using observations from some of the largest ground-based and space telescopes. He has played a leading role in several major projects, including the James Webb Space Telescope, the MOONS spectrograph for the Very Large Telescope, and the ANDES spectrograph for the Extremely Large Telescope.

Views: 42

Orange County Star Party. May 09,2026
2026-05-09 19:00 - 22:30 | Online
Hi we will be having our first Orange County star party at the Augustine Staging Area. You musty sign up at the OC Park website.
https://letsgooutside.org/
You must pre-register to attend and you must arrive before 8pm. No late entries and no walk ups. Gates will open at 7:00PM and close promptly at 8:00PM The event is scheduled to end at 10:00pm with a final close and out at 10:45PM.
If you have questions please contact Alan Smallbone.
Further details to be added.
Views: 42

Online Beginner's Class
2026-06-05 19:00 - 21:00 | Online
This is a free and open to the public online event, to attend please register with zoom by clicking here at or after 6:40pm.
The 4th session of the Beginners Astronomy Class covers the science behind the telescope.
How do our eyes actually perceive objects we see in the telescope and what is the physics that allows that perception.
For details, please visit here and download the sample information PDF package.
Views: 42

General Meeting - June 2026
2026-06-12 19:30 - 21:30 | Irvine Lecture Hall of the Chapman University, 336 N Center St, Orange, CA, 92866, United States
Join Zoom

Tonight’s meeting will be online only.
Chapman University just notified us that we can not use their facility for tonight’s meeting.

The Big Eye: Palomar Observatory’s past and future

Palomar Observatory is just two hours from Orange County. Home to the 200-inch Hale telescope—once the world’s largest telescope—and an array of smaller facilities, it is one of the most productive astronomical research sites in the US. This talk will give an overview of Palomar’s development and rich history, and will discuss how creative ideas and evolving instrumentation help to keep the Observatory at the forefront of astronomical discovery as it nears its 100th birthday.

Geoffrey Mo is a Brinson Postdoctoral Fellow at the Carnegie Observatories and at Caltech. His main research interests are in the birth, evolution, and death of binary stars, particularly those involving white dwarfs, neutron stars, and black holes. He uses large telescopes on the ground and in space to study these systems, which are responsible for many of the most energetic events in the universe. He is also interested in new astronomical instrumentation and is leading the development of a new high-speed imager for the 200-inch Hale telescope at Palomar Observatory. Geoffrey was an undergraduate at Carleton College and earned his PhD at MIT.

Views: 42

OCA Astrophysics SIG Meeting
2026-06-19 | Orange Coast College, Building 40, Astronomy House, Merrimac Way, Costa Mesa, CA, 92626, United States
There will be no ASIG meeting in June. Instead we recommend attending the Society for Astronomical Sciences Annual Symposium, June 25-27, Ontario, CA., and/or the American Astronomical Society Summer Meeting, Pasadena, CA, June 14-18. Click on either conference title to be directed to the conference webpage. These meetings provide the opportunity for rich interaction with the worldwide Astronomical and Astrophysics communities.
Views: 42

OCA Astrophysics SIG Meeting
2026-06-19 19:00 - 22:00 | Orange Coast College, Building 40, Astronomy House, Merrimac Way, Costa Mesa, CA, 92626, United States
Views: 42

Beginner's Class In-person event(New Location)
2026-07-06 19:30 - 22:30 | Orange Coast College, Outside Planetarium, 2701 Fairview, Costa Mesa, CA, 92626, United States
This is a free and open to the public event (In-person event only).
The 5th session of the Beginners Astronomy Class is the “How to Use Your Telescope”.
If you have a telescope and would like some help learning to set it up and use it, attend this Hands-on class.
For details, please visit here and download the sample information PDF package.
Event is held at Orange Coast College, near Planetarium.
Look for Planetarium Parking, LOT E
Parking is $5.35 for a virtual daily parking permit and can only be paid online or by app at this time. There is no kiosk at the parking lot.
For instructions click on:
https://orangecoastcollege.edu/about/parking-and-public-safety/parking/index.html

Scroll down to: PURCHASE VIRTUAL DAILY PARKING PERMITS. You want LOT E which is ZONE 92847.

Click on the link for PassportParking.com to pay online. Go to the Menu and click on the PayOnline Button and follow the prompts. If you want to download the app, also usable at many other locations in the region and in the US, please follow the instructions provided by the App.
Views: 42

General Meeting – July 2026
2026-07-10 19:30 - 21:30 | Online
Join Zoom

Free and open to the public.
This meeting will be online only, please do NOT go inperson.

Searching for Signs of Life

on Jupiter’s Ocean-Bearing Moons

Using NASA’s Europa Clipper mission as our guide, we’ll journey to Jupiter’s icy moons – worlds that may contain vast oceans beneath their frozen crusts. We will examine the evidence to support the possibility of finding life at this seemingly-unlikely locale in our Solar System. We will also discuss the motivation for the search for life beyond Earth, and the impact of the search on humanity.

Robin Metcalfe is an associate professor at York University in Toronto, where she has been teaching physics and astronomy for over 25 years. She is also the Director of York’s Division of Natural Science, which offers courses spanning a broad range of scientific fields and designed for diverse audiences from any academic discipline for the purpose of engaging students in topical scientific issues and instilling an appreciation for scientific exploration. Robin is also active in public outreach, giving Astronomy-themed talks to a variety of audiences, including astronomy clubs and other interest groups. Through her teaching and outreach, Robin shares her passion for the night sky and the outdoors. She teaches students to appreciate what the night sky has to teach us, to gain perspective from our place in the Universe, and to value our precious planet Earth.
Views: 42

Heritage Montessori Lake Forest
2026-07-13 10:00 - 12:00 | Heritage Montessori Lake Forest, 2900 Portola Parkway, Lake Forest, 92630, United States
This event does not require anyone to bring their telescope! Rather, the school is asking for speakers to talk to its students about the night sky and astronomy, during the daytime.
The age of the audience is between 2 and 7 years, so don’t say anything too technical.
Views: 42

OCA Board Meeting
2026-07-26 11:00 - 13:00 | Online
OCA Board Meeting will be held via zoom at 11:00am. All current members are welcome to attend. Contact the club secretary for the link.
Views: 42

In-person Beginner's Class(New Location)
2026-08-07 19:00 - 21:00 | Orange Coast College, Building 40, Astronomy House, Merrimac Way, Costa Mesa, CA, 92626, United States
This is a free and open to the public event (in person event only)
The 6th session of the Beginners Astronomy Class covers the basics of astrophotography, covering different types of imaging, how different types of cameras are used for this kind of photography, and other equipment and considerations for taking a good picture.
This session is taught by Kyle Coker, who is active in the club’s AstroImaging special interest group.
Free and open to the public as well as members of OCA.
For details, please visit here and download the sample information PDF package.
Event is held at Orange Coast College, Building 40, Astronomy House.
Parking is $5.35 for a virtual daily parking permit and can only be paid online or by app at this time. There is no kiosk at the parking lot.
For instructions click on:
https://orangecoastcollege.edu/about/parking-and-public-safety/parking/index.html

Scroll down to: PURCHASE VIRTUAL DAILY PARKING PERMITS. You want LOT E which is ZONE 92847.

Click on the link for PassportParking.com to pay online. Go to the Menu and click on the PayOnline Button and follow the prompts. If you want to download the app, also usable at many other locations in the region and in the US, please follow the instructions provided by the App.

Views: 42

General Meeting – August 2026
2026-08-14 19:30 - 21:30 | Online
Join Zoom

Free and open to the public held online-only.

From Data to Discovery:

Communicating PACE Science to the World

NASA’s Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission provides unprecedented insights into Earth’s interconnected ocean and atmospheric systems. But how do we transform complex scientific data into meaningful public understanding?
This presentation will introduce the PACE mission and explore strategies for communicating Earth science to diverse audiences. We’ll discuss the challenges of sharing complex ocean-atmosphere research, making data accessible to educators and students, and engaging communities in understanding their connection to global environmental systems.
This will show how PACE is not just observing our planet, but inspiring the next generation of Earth science enthusiasts and informed citizens.
The presentation with the reference links can be downloaded by clicking here.

Carina Poulin is a scientific designer at The Ocean Ecology Laboratory at NASA’s Goddard Space Flight Center, where she works at the intersection of Earth science, visualization, and communication. She has a scientific background in ocean color remote sensing and phytoplankton optics. Her work focuses on making complex satellite missions like PACE more accessible and meaningful to scientists, students, and the public.
Views: 42

Online Beginner's Class
2026-09-04 19:00 - 21:00 | Online
This is a free and open to the public online Zoom event, to attend please click here at or after 6:40pm
The 1st session of the Beginners Astronomy Class gives a general overview of all of the different objects you can see in the night and day time skies, with some history and information about what they are and their significance. An overview of the current scientific understanding of the Universe’s beginning, present and future is also covered.
For details, please visit here and download the sample information PDF package.
Views: 42

General Meeting – September 2026
2026-09-11 19:30 - 21:30 | Online
Join Zoom

Free and open to the public held online-only.

Sounds of the Stars:

Journey to the Center of a Star

What lies at the center of a star? A stellar core is surrounded by a million Earth’s worth of plasma, so we cannot see it directly. However, the immense power of a star’s radiation causes nearly all stars to pulsate, creating “star quakes” at their surfaces. These oscillations are a collection of musical notes that uniquely define each star and are determined by its internal structure, just as the sound of a musical instrument is determined by its size and shape. Join me for a cosmic symphony as we journey to the center of the Sun, Saturn, white dwarfs, red giants, and heartbeat stars.

Jim Fuller is a professor of theoretical astrophysics at the California Institute of Technology. His research covers a broad array of topics, ranging from Saturn’s moons to massive stars that explode as supernovae or collapse into black holes! Recently he has been studying the evolution of massive stars just before supernova, the neutron stars and black holes that they produce, asteroseismology and magnetic fields inside of red giants, pulsations of tidally distorted stars, the deep interior of Saturn as revealed by its rings, and the long-term orbital evolution of exoplanets and moons.

Views: 42
