"No known roof is as beautiful as the skies above."

– Michael O'Muircheartaigh

CAA Public Events 2019

Young Observer at C16

A young observer peers through the CAA's vintage Celestron 16 telescope.


The CAA hosts at least 12 Saturday Public Observing events featuring a guest speaker that is followed—weather permitting—by celestial viewings through telescopes at the facility. During viewing hours, society members will be available to answer questions and provide everyone with an opportunity to look through the Society's telescopes and those of our members.

This site will be updated through out the year as we assemble our speakers and events.

 Future Presentations

November 19th 7:30 PM

This event will be held in person as well as Zoom


Title: Probing the Earth's Magnetosphere through Energetic Particles

Presenter: Sanjay Chepuri, Graduate Research Assistant

Summary: The magnetosphere is made of the Earth's magnetic field and embedded inside of the sun's field. It is a complex system surrounding the Earth and protecting us from solar radiation. In this talk, I will talk about the magnetospheric system and especially focus on energetic particles and how we can use them to track some of the most important processes that occur in the magnetosphere.
Bio: Sanjay Chepuri is in his fourth year as a Ph.D. student at the University of Iowa. He works with Dr. Allison Jaynes to study energetic particles in the Earth's magnetosphere using spacecraft data, primarily from NASA's Magnetospheric Multiscale (MMS) mission.

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December 10th 7:30 PM - Virtual Event Only

 Title: TBD

Presenter: TBD



2023 Presentations


January 14th 7:30 PM Virtual Event Only

 Title: TBD

Presenter: TBD



February 25th 7:30 PM Virtual Event Only

 Title: TBD

Presenter: TBD





2021 Past Presentations

January 16, 7:30 p.m.

Nancy Atkinson, contributing editor for Universe Today- www.universetoday.com

Eight Years to the Moon: The History of the Apollo Missions

"The stories of 45 engineers and scientists who worked behind the scenes to make it possible to land on the Moon. Many of these people have gone unheralded for their work, but their contributions were vital to meeting the challenges of such an audacious project. These are stories from the 1960's that you won't find anywhere else."

February 13, 7:30 p.m.

Charles (Chuck) E. Allen, Vice President, Astronomical League

Cosmic Horizons

Cosmic Horizons explores the limits of human visibility imposed by planetary curvature, photon sensitivity of the human eye, and the speed of light in an expanding universe. We briefly explore the definition of planetary horizons and the role of planetary size in defining them. Next, we examine the faintest astronomical objects we can see with and without optical aid, and the smallest number of photons theoretically detectable by humans. Finally, we discuss the four horizons imposed by time and the speed of light (the Hubble distance, cosmic particle horizon, cosmic event horizon, and future visibility horizon) and consider how these horizons change in an accelerating universe and what effect they have on what we can, or ever will, see.

Chuck Allen

Chuck is currently Vice-President, and also past-President, of the Astronomical League. He founded the League’s 30 year-old National Young Astronomer Award in 1991, received the G. R. Wright Award for service in 1998, and holds the League’s Master Outreach Award with more than 500 public programs to his credit. He is a League Master Observer with 38 programs completed, three of which he coordinates.

Chuck is Program Director for the Evansville Astronomical Society and past President of the Louisville Astronomical Society (1991-94). From 1995 to 2002, he served as Judge, and once as Lead Judge, in earth and space science for the Intel International Science and Engineering Fair. Chuck graduated from Duke University in 1970, served as a U.S. Air Force officer from 1970 to 1974, and graduated from the University of Kentucky College of Law in 1977. He was a partner with Kentucky's largest law firm, Frost, Brown Todd LLC, where he practiced for 27 years.


March 6, 7:30 p.m.

Tom Field, Field Tested Systems

You can almost touch the stars

Even if you wanted to touch a star, they’re all impossibly distant. Despite these great distances, astronomers have learned an enormous amount about stars. How? The most common method to study the stars is called spectroscopy, which is the science of analyzing the colorful rainbow spectrum produced by a prism-like device. Until recently, spectroscopy was too expensive and too complicated for all but a handful of amateurs. Today, though, new tools make spectroscopy accessible to almost all of us. You no longer need a PhD, dark skies, long exposures, enormous aperture … or a big budget! With your current telescope and FITS camera (or a simple web cam or even a DSLR without a telescope) you can now easily study the stars yourself. Wouldn’t you like to detect the atmosphere on Neptune or the red shift of a quasar right from your own backyard?! This talk, with lots of interesting examples, will show you what it’s all about and help you understand how spectroscopy is used in research. Even if you are an armchair astronomer, understanding this field will enhance your understanding of the things you read and the night sky.

Tom Field

Tom Field has been a Contributing Editor at Sky & Telescope Magazine for the past 7 years. He is the author of  the RSpec software (www.rspec-astro.com) which received the S&T “Hot Product” award in 2011. Tom is a popular speaker who has spoken to hundreds of clubs via the web and in-person at many conferences, including NEAF, the NEAF Imaging Conference, the Winter Star Party, the Advanced Imaging Conference, and other


April 3, 7:30 p.m.
Professor Steven Spangler, University of Iowa Physics and Astronomy
O Type Stars in the Night Sky

We learn in school that stars are like the Sun, only very far away.  Or, the Sun is a star which is very close to us.  How similar are the stars in the night sky to our Sun?  A short answer would be that they are similar in kind, but quite different in degree.  They range enormously in mass (amount of matter in them), brightness, and temperature at their surfaces.  The most massive, brightest, and hottest stars are called the O stars.  The term “O star” is a holdover from early astronomical research, but the category contains a set of stars with extravagant properties.  In particular, they are much hotter and much brighter beacons than our Sun.  In spite of this, none of the 26 brightest stars in the sky is an O star.  In this talk, I will explain why this is true, and where you can find stars in the night sky that are these remarkable objects. 

Topic: O Stars in the Night Sky
Time: Apr 3, 2021 07:30 PM Central Time (US and Canada)

May 1, 8:00 p.m.


Dr. Sadie Elliott, Postdoctoral Research Scholar

University of Iowa Department of Physics and Astronomy

New discoveries made by the Juno mission to Jupiter

NASA’s Juno mission to Jupiter was launched in 2011. Since its arrival at Jupiter on July 4, 2016, Juno has made a number of scientific discoveries. Juno is the first spacecraft to make in-situ measurements of Jupiter’s polar magnetosphere and aurora. Some surprising high-latitude discoveries include observations of highly energetic electron beams, intense broadband plasma waves, and elevated electron densities due to the presence of the Io plasma torus. In this talk, I will present an overview of the Juno mission and the University of Iowa’s involvement. I will also present scientific results from Juno’s prime mission, specifically observations made by Juno’s radio and plasma wave instrument.


May 15, 2021

8:30 p.m.

Rachael Filwett , Ph.D.

Title: Solar energetic particles and their influence on modern society


In our technologically-driven society we have become increasingly reliant on stable power supplies. Similar to terrestrial based weather sources that can be devastating to a region, such as the derecho last year, outer space can produce a variety of weather hazards. I’ll discuss how these hazards vary by terrestrial location, and how they come in ‘seasons’. The number of spacecraft is increasing rapidly, and NASA has plans to return astronauts to the moon and then on to Mars, adding urgency to mitigate space weather risks.  I’ll talk about what space weather is, what we can do about it, and how my personal research plays a small role in this important task.

Virtual Meeting Information:

Topic: Space Weather for a Modern Society
Time: May 15, 2021 08:30 PM Central Time (US and Canada)


June 12, 8:30 p.m.

Presenter: Dr. Charles Kerton- Associate professor of astronomy 

The Department of Physics & Astronomy at Iowa State University

Title: Adventures in Citizen Science or Astronomy for Cloudy Nights

This talk will describe work done by astronomers based at Iowa State University and the Adler Planetarium to understand the nature of thousands of compact, infrared sources identified by the over 50,000 citizen scientists participating in the Milky Way Project. Most of these objects represent an early stage in the evolution of massive stars.Trying to understand why many of these objects were not identified in previous Galactic infrared surveys leads to some interesting insights into how the mid-infrared emission from a massive star-forming region changes as it evolves. I will also briefly describe some of the other active citizenscience projects related to astronomy.

Bio: Dr. Charles Kerton is an associate professor of astronomy in the Department of Physics & Astronomy at Iowa State University. His research focus is on observational studies of high-mass star formation and the effect of massive stars on the interstellar medium using infrared and radio data. At Iowa State he also enjoys teaching classes ranging from undergraduate survey courses to specialized graduate seminars. Even though astronomy is his job, he still likes to look at the night sky from time to time just for fun!



July 10, 8:30 p.m.

Presenter: John Leeson, Cedar Amateur Astronomers Vice President

Title: Observing the Sky for Beginners

If you are somewhat new to trying to observe the night sky with your new telescope or binoculars, or just starting to think about observing the night sky, then maybe we can help get you started. One of the first things beginners want to know is what can I see and how do I find it? That is what we hope to answer here tonight. There is always something to look for whether you are using just your eyes, binoculars, or your amateur class telescope and there are lots of tools to help you figure it out. We will be using printed Sky Maps and Stellarium planetarium software primarily. There is no cost for these tools, the software is open source and free to use and the sky maps can be downloaded and printed for free. With these you can plan your observing night activities ahead of time and also know what you can expect to see, so you will know how to tell if you are successful.



July 31, 8:30 p.m.

 Presenter: David Falkner

Title: The Mythology of the Night Sky
"Most of the constellations we see from the northern hemisphere have their roots in Greek and Roman mythology. Dave will talk about the history leading up to the naming of the constellations, some of the stories found in the constellations, and how they relate to life in ancient Greece and Rome.

Dave will also talk about the tradition of naming solar system objects based on Greco-Roman mythological characters, one significant deviation from that, and how in more recent times the naming convention has expanded to other mythologies."


Dave Falkner has been a life-long amateur astronomer. He first became interested in Astronomy as a pre-teen when his father took him to a show at the Holcolm Planetarium in Indianapolis.  He became hooked and has had an interest in astronomy ever since.  As a teenager he ground a 6” mirror and built his first telescope.  As a Naval Officer stationed in Monterey, California he was involved with the Friends of MIRA (Monterey Institute for Research in Astronomy) where he conducted outreach to local schools associated with the return of Halley’s Comet.

After a successful 20-year career Dave retired from the US Navy and settled in Minnesota where he became an active member of the Minnesota Astronomical Society. He has served as its President and enjoys performing astronomical outreach often speaking to groups at libraries, nature centers and schools. He is a NASA/JPL Solar System Ambassador and has authored the book “The Mythology of the Night Sky – Greek, Roman and Other Celestial Lore, Second Edition.”



August 14, 12 noon and 3:00 p.m. – 6:00 p.m.

 This event will be held in person as well as Zoom

Presenter: CAA Treasurer Mr. Carl Bracken

Title: Our Sun and Solar Activity Cycles

The presentation will be at noon, then the recorded program will be played back at 3pm. Solar observing using the association's solar-filter equipped telescope will follow the presentation and again following the 3pm playback. CAA members will be on-site to give tours of the observatory, assist with telescopes and answer questions. Only specially equipped optical aids can be used to observe the sun without endangering eye damage. CAA has four optical telescopes with solar filters and two sun projection viewers, plus some of the members will bring thier own telescopes with solar filters.

Synopsis:The sun completes one full magnetic field cycle every 22 years on average. The familiar cycle of sunspot minimum to sunspot maximum back to minimum lasts on average 11 years; two full sunspot cycles are part of each solar magnetic field cycle. The Wilcox solar Observatory or WSO near the campus of Stanford University in Northern California has produced daily solar polar field measurements since May 1976 forming a unique dataset of key solar characteristics unmatched anywhere in the world. In this presentation we will look at the WSO dataset to illustrate the dynamic nature of the solar magnetic field.

The geologic record shows us that Earth's magnetic dipole field also shifts over long time frames. Like the sun the geomagnetic field surrounding our planet is complex and has different cycles on vastly different time horizons. The more familiar magnetic pole reversal is thought to have last occurred approximately 780,000 years ago. The geologic record also points to another magnetic pole shift event that occurs on a time horizon of approximately 12,000 – 13,000 years known as a geomagnetic excursion. Unlike the full pole reversal, the excursion event does not permanently change the orientation of the dipole. However, it does introduce a significant reduction in field strength and temporarily changes pole orientation. The duration of the excursion event is thought to last a few thousand years with the poles eventually returning to their original orientation. The geomagnetic field is important for everyday activities such as navigation, and protection from high energy radiation from our sun as well as our own galaxy, and even deep space beyond our Milky Way.

In this presentation we will look at how the dynamic solar magnetic field and the geomagnetic field interact and some of the impacts from the interaction. We will also look at some interesting cold war era history of discovery by the US military studying the impacts on navigation over the geomagnetic North pole during long range bombing missions.



August 28, 8:00 p.m.

This event will be held in person as well as Zoom

Presenter: Riley Troyer, graduate student, University of Iowa Department of Physics and Astronomy

Title: Northern Lights in Iowa: a discussion about the aurora, their science, common misconceptions, and the possibility of seeing them here

Bio: I was born and raised in Fairbanks, Alaska. I’ve always been interested in science, but in high school I discovered astronomy and was hooked. This led me to pursue a degree in physics from the University of Alaska Fairbanks. While studying physics, I started researching the aurora (northern lights). Living in Alaska, I’ve seen the aurora many times, but understanding how it is formed gave me an entirely new perspective. Once again, I was hooked. Funny enough, I decided to move south to continue this interest as a space physics graduate student at the University of Iowa. I am now in my 4th year as a Ph.D. candidate studying a specific type of northern lights known as pulsating aurora. Outside of research, I have an interest in science policy and helped found the UI science policy and communication student organization (Connecting Science to Society). I am also an avid cyclist and cross-country skier and enjoy a variety of other outdoor activities. However, I’m only now getting used to the hot and humid Midwest summers.  

Synopsis: The aurora, also known as the northern/southern lights, are a majestic and awe-inspiring display of nature that occurs in the far north and south. These green, red, and sometimes even blue curtains of light have been marveled over for as long as humanity has existed in such places. However, our scientific understanding of them is not nearly as old and there is still much we don’t understand. In this talk, I will describe how the aurora are formed and address some widespread misconceptions. Since the sun is becoming more active, which leads to stronger aurora, I will also discuss how to tell when we might catch a glimpse of them here in Iowa and if so, how to best take advantage of that. I’ll also describe my own research area, a fascinating type of northern lights called pulsating aurora and how they differ from “normal” aurora. Finally, I’ll touch on why it is important that we study these lights and the impacts they can have on society.



September 25, 7:30 p.m.

This event will be held in person as well as Zoom

Zachary Luppen – PhD Student of Aerospace Engineering, Department of Aerospace Engineering at Iowa State University

Developing Reusable Rockets to Reach the Moon and Mars: What It’s Like to Work for SpaceX


Space Exploration Technologies Corporation (SpaceX) was founded in 2002 by Elon Musk with the goal of reducing costs to space access and to enable the colonization of Mars. After launching the first privately funded liquid-propellant rocket to reach orbit in 2008, the company has made leaps in bounds in space exploration technology. Applying a vertical integration structure and working towards rocket reuse from the beginning, the company has provided much easier and cheaper access to space. In Spring 2020, the company’s work culminated in the launch of Crew Dragon Demo-2, the first private launch of astronauts to orbit and the International Space Station (ISS).

During Summer 2021, I was invited to intern at SpaceX as part of the core avionics engineering group. My work involved rigorous testing of electrical, electronic, and electromechanical (EEE) components to ensure reusability on multiple missions. In this talk, I will discuss the mission and projects of SpaceX, describe the work I performed (to the extent that I am allowed), and tell you about the company’s fast-track plan to put humans on Mars.


Zachary Luppen is a PhD student of aerospace engineering at Iowa State University. Originally from Omaha, Nebraska, he attended the University of Iowa from 2015-2018, earning degrees in astronomy and physics, with honors. During that time, he participated in a handful of events with the Cedar Amateur Astronomers, including giving past talks at the observatory. At Iowa State, he is currently studying formal methodologies used to specify, verify, and validate space systems. He is expecting to achieve his MS in Fall 2021 and his PhD in Spring 2024. In his free time, Zachary enjoys flying as a private pilot, skydiving, reading, biking, and running.




 October 16, 7:30 p.m.

This event will be held in person as well as Zoom

Presenter: Dr. Jasper Halekas

University of Iowa, Department of Physics and Astronomy

 Title: Earth’s Moon: International Observe the Moon Night

The Moon, our nearest neighbor and closest companion, is a constant presence in the sky and in our culture. I will discuss the history of lunar exploration, what we have learned about the Moon through this exploration, and some of the many things we still don't know about the Moon. I'll end with a look to the future, describing a new mission to the Moon that will launch in a few years, with involvement from the University of Iowa. 

Jasper Halekas is an Associate Professor in the Department of Physics and Astronomy at the University of Iowa. Prof. Halekas's research focuses on the impact of the Sun and the solar wind on our solar system and its evolution. He designs and builds spaceflight instruments to measure charged particles, and uses these measurements to explore the interplanetary medium and the environments near the various bodies of our solar system.




October 30, 7:30 p.m.


Astronomy Professor Larry Molnar believes he can find the unfindable – a star that is about to explode!

When Larry and a small team of students stumble across a strange star, they embark on a dramatic journey of scientific discovery, which brings the unlikely team into the international spotlight. But others in the astronomical community are skeptical, and Larry’s professional reputation hangs in the balance. In production since 2014, Luminous, a feature documentary by award-winning filmmaker Sam Smartt (Wagonmasters), follows Larry’s journey to test his unprecedented prediction, knowing that its success or failure will unfold squarely in the international spotlight.




 November 27, 7:30 p.m.

Presenter: Dr. Steven Spangler, Emeritus Professor, Department of Physics and Astronomy, The University of Iowa

Title: A Bubble in Space

 We usually think of the space between the stars as being completely empty.  However, this space is filled with very dilute matter that astronomers call the interstellar medium.  Research has shown that the Sun is located within an unusual hole in the interstellar medium called the Local Bubble or Local Cavity.  There has to be some matter in the Local Bubble, but scientists still disagree on its pressure and temperature.  I will describe the observations that show this bubble exists, discuss how it was formed and is maintained in its present condition, and what it implies for other aspects of astronomy.  



 December 18th 2021, 7:30 PM - Canceled



2022 Past Presentations



January 29th 2022, 7:30 PM Virtual Event Only

 Title: Big Bang Nucleosynthesis and the Primordial Helium Abundance

Presenter: Professor Evan Skillman

Synopsis: Professor Evan will provide a review of Big Bang Nucleosynthesis, how to measure cosmological parameters, and specifically his history with making measurements of the primordial helium abundance.



February 26th 2022, 7:30 PM Virtual Event Only

 Title: Studying the Beginning of the Universe from the Bottom of the World

Presenter: Professor Clement Pryke - University of Minnnesota

Abstract: The Cosmic Microwave Background (CMB) is the thermal glow from the
Big Bang birth of our Universe. Studying its pattern has taught us an enormous
amount about the content, evolution and fate of the Universe in which we find
ourselves. Basic theory allows us to push our understanding back to an
enormously high energy state, and a very particular set of conditions which
apparently applied at that time. However, we need a much more radical theory
dubbed "Inflation" to explain how those conditions were set up. If inflation
did in fact occur it will have launched into the fabric of spacetime a
background of gravitational waves, and searching for this signal is currently
one of the most important quests in all of cosmology. The world leader in this
field are the BICEP/Keck series of experiments which are located at the South
Pole in Antarctica. This talk will describe the cosmological paradigm, the
basics of the CMB, and then move on to how our telescopes work and how we
search for inflationary gravitational waves.

Bio: Pryke is an experimental cosmologist and educator. His research currently
centers on the cosmic microwave background (CMB) - the after glow from early
times when the Universe was a smooth hot plasma. By studying the CMB we can
learn much about the origin, contents and ultimate fate of the Universe - CMB
studies are at the center of the current "golden age" of cosmology. Pryke has
played a leading role in the construction and operation of a series of CMB
telescopes sited at the South Pole in Antarctica, and the analysis of the data
they produce. He was a key member of the DASI team which produced the first
detection of the polarization of the CMB. He then went on to co-lead the QUaD
experiment - another ground breaking CMB polarimeter. Currently he is
co-leading the BICEP/Keck collaboration which take sensitivity to the next
level in the quest to detect gravity waves spawned by inflation in the first
instant after the big bang.



March 26th 2022, 7:30 PM - In person & on Zoom

 Title: Open Star Clusters: Jewels of the Spring Sky

Presenter: Professor Steven Spangler - Professor Emeritus - University of Iowa

Synopsis: Open star clusters are some of the favorite objects of amateur astronomers, and this time of year (March- April) is about the best time to see them. We can see some open clusters with the naked eye, and many more are visible with a pair of binoculars. Telescopes show them for what they are, collections of hundreds or thousands of stars moving together through space. Although we have known their basic properties for many decades, recent results from the GAIA spacecraft and large ground-based telescopes have provided major advances. In this talk, I will describe how to find them in the night sky, basically what they are, and what new we have learned in the last 5 to 10 years.




April 23rd 2022, 8:00 PM - In person & on Zoom

 Title: The LAMP Rocket Mission: Shining a Light on Pulsating Aurora (Challenges and Successes)

Presenter: Professor Allison Jaynes - Assistant Professor - University of Iowa

and Riley Troyer - Graduate Research Assistant - University of Iowa

Synopsis:  Pulsating aurora is a fascinating type of Northern Lights - it flashes on and off in large patches across the sky. Researchers have known for decades that it contains higher energies than the more well-known green arcs and curtains. Yet many questions about this aurora still remain. To investigate the aurora and Earth’s upper atmosphere, we launched a sub-orbital sounding rocket 500 km above Alaska to take measurements from within the aurora itself. Sounding rockets (essentially ballistic missiles, minus the munitions) offer a direct trajectory through this region for a 15-minute parabolic flight, during which we can obtain high resolution measurements of particles and fields. 

The path to scientific success is often portrayed as a smooth road. That’s typically far from reality. Such was the case with the LAMP rocket mission. Resembling closer to a gravel road in rural Iowa, the mission was a success, but the path to get there was bumpy. In this presentation, we will tell the story, both highs and lows, of the LAMP rocket and its mission to investigate pulsating aurora.



May 7th 2022, 8:00 PM

 Title: What scientists can learn from studying meteorites and their impacts

Presenter: Professor David Peate

Synopsis: Sending spacecraft to planetary bodies is an expensive way to collect samples, but nature does this for us for free thanks to the regular delivery of meteorites 'falling from the sky'. In this talk, I will discuss how the study of meteorites can reveal details of the early history of our Solar System and how planets formed, and how we know where in the Solar System most meteorites come from. I will also talk about scientists finding unusual materials in some meteorites like organic molecules as well as grains that are older than the Solar System. I will finish by describing some of my own reseach on the Monturaqui impact crater in Chile that was formed by the impact of a ~15 m diameter iron meteorite, creating a 450 m diameter crater, and melt ejecta containing droplets of metal.

Bio: David W Peate is a Professor of Geochemistry at the University of Iowa, and currently Chair of the Department of Earth & Environmental Sciences.His research focus is understanding how the Earth's mantle melts and how magmas rise through the Earth's crust to form volcanoes, through detailed study of the chemical composition of volcanic rocks and minerals. He has had a life-long fascination with planetary geology inspired by watching the Apollo 11 moon landings as a small child in the UK, which has led to side projects looking at impact craters and meteorites.



May 21st 2022, 8:30 PM

Presenter: Professor Hai Fu - Associate Professor - University of Iowa 

Title: “How did we discover the first cold gas stream feeding an early massive galaxy?” 

Synopsis: Every discovery has an untold story. During this CAA public night, I will share with you the story behind the Iowan discovery of the massive cool gas stream that is providing the fuel for star formation to a massive galaxy 11 billion years ago. Here is a nice description of the study from the VICE News article (https://tinyurl.com/gama0913): If you peer into the deep reaches of time and space to glimpse the universe when it was just a few billion years old, you’ll see an ancient era populated by many massive galaxies. Simulations suggest these galactic behemoths must have been fed by cold gas in dark matter filaments—structures that make up the cosmic web that connects galaxies in the universe—but the nature of these gas infusions has remained murky in the absence of direct observations. This system is by far the best evidence for the elusive cosmic filaments that supercharge ancient galaxies with cold gas. 

Bio: Hai Fu grew up in Yili, an oasis surrounded by mountains and deserts near the border between Kazakhstan and China. Introduced to the night sky by his elementary-school geology teacher, he became an amateur astronomer at an age of ten. His first telescope was a 6-cm (2.4-in) refractor, which he carried on a bike to stargaze for seven years before entering the only astronomy undergraduate program in China at that time. He earned an Astronomy doctor’s degree in Hawaii and held two postdoctoral researcher positions in California. Today he teaches Astronomy at the University of Iowa and he observes galaxies near and far with large telescopes across the globe to study their cosmic evolution. First drawn into modern astronomy by Galileo spacecraft’s flyby images of asteroids, he is honored to have an association with a main-belt asteroid: 22413 Haifu (1995 UB13).


June 18th 2022, 8:30 PM


Title: HaloSat - A CubeSat that Studied the Hot Halo of the Milky Way

Presenter: Professor Philip Kaaret, Departmental Chair, University of Iowa Physics and Astronomy

The Milky Way is surrounded by a "halo" of gas at temperatures of millions of degrees Kelvin. HaloSat was a small satellite (CubeSat) that performed an X-ray survey of the sky in order to better understand the nature and origin of this plasma. We found that the plasma is powered primarily by energy released during the lives and deaths of massive stars that feeds back into the circumgalactic medium.  We describe the design, construction, and operation of HaloSat and some of the key science results.

Bio: Philip is the Departmental Chair and Professor in the Physics and Astronomy Department at the University of Iowa. Kaaret studies X-rays and gamma-rays from black holes, neutron stars, and the hot gas surrounding galaxies. He led the design and construction at the University of Iowa of HaloSat, which was the first CubeSat funded by NASA’s Astrophysics Division and studied the hot halo of the Milky Way galaxy.

Research Interests include X-ray and gamma-ray astronomy and instrumentation; CubeSats; black hole binaries; galactic X-ray halos.


July 9th 2022, 3:00 - 6:00 PM - Solar Saturday

This event will be held in person as well as Zoom

 Title: Interplanetary Connections – Powerful forces originating on our sun impact every part of the solar

The Sun provides a constant flow of energy radiating everywhere throughout the interplanetary system we know as the solar system. People across the planet have observed the motions of the Sun across the sky from ancient societies that needed a method to plan a wide range of societal activities such as planting and harvesting. Telescopic sunspot observations by Galileo over four hundred years ago brought about rapid changes in the way people thought about the Sun and our place in the solar system. One of the best known and truly impactful solar events occurred on September 1 st , 1859. Large telegraph networks had begun operating in parts of the world starting around 1855 establishing the Victorian internet. Unknown to telegraph system owners and operators was how vulnerable the systems were to a powerful Earth facing solar flare event. Today around the globe and orbiting high overhead is an array of dedicated solar observing platforms generating massive amounts of data daily which is used for a wide range of applications to help shield the countless layers of technology that make of the fabric of modern society today. A hot topic of debate in the scientific community for years now is what would happen to the modern technology driven world today with a Carrington level event?

Presented: Carl Bracken Treasurer Cedar Amateur Astronomers, professional security systems
designer for Control Installations of Iowa. Active observer and photographer of the natural world day
and night.


July 12 at 9am:  Live Viewing of The James Webb Space Telescope’s First Images -

Guest Speaker: Mark Brown - NASA JPL Solar System Ambasador

This event will be held in person as well as Zoom

Celebrate with the world the first images from the James Webb Space Telescope as Cedar Amateur Astronomers host a live community viewing at the Eastern Iowa Observatory and Learning Center. NASA’s live feed will be transmitted in July to sites around the world, including the observatory and hundreds more throughout the United States.

NASA plans a May announcement to set the date for the July viewing of the first images called “first light” by astronomers. Check back to this event page or our Facebook page for updates on the exact date and time of this viewing.

The event will begin in mid-morning with a 60- to 90-minute live feed viewing of the first images transmitted from NASA’s $10 billion space telescope. Stay for a live-feed afternoon panel of NASA experts who will discuss the scientific impact of the images. Come early or stay late for a tour of the observatory’s exhibits and displays and several activities geared toward learning about the Webb Telescope.

Launched on Christmas Day 2021, the Webb Telescope now sits in a stable orbit past the moon, a million miles from Earth. This marvel of technology has mirrors ten times the size of Hubble Space Telescope and collects light in the infrared spectrum. The Webb Telescope’s advanced instruments gather data from objects billions of light years away. The data and images will provide scientific information from the early universe.


July 23rd 2022, 8:30 PM

Title: Hot Stars: From Winds to X-rays

Presenter: Sean Gunderson , Graduate Teaching Assistant, University of Iowa Department of Physics and Astronomy

 In the night sky, the brightest and most common stars we see are the so called “hot stars.” These stars dwarf our Sun in not just temperature, hence their name, but in every category from size to brightness. One of the more intriguing properties of these stars is that they are quite bright in the X-ray band of light, much more so than the Sun. How these X-rays are generated is surprising and a hot topic of research for many years. I will talk about what exactly a “hot star” is and the mechanics of how they generate X-rays.


August 14 at 1pm:  Live Viewing of The James Webb Space Telescope’s Images

Guest Speaker: Mark Brown - NASA JPL Solar System Ambasador

This event will be held in person as well as Zoom

Bring the kids and join Cedar Amateur Astronomers as we continue to celebrate the James Webb Space Telescope. Doors open at 1 PM on Sunday, August 14, 2022. 

NASA JPL Solar System Ambassador Mark Brown will discuss Webb's first images from July, and any new images released since then. In this fascinating interactive discussion, Mark will give us an update on some of the science learned from these images and answer questions from the audience.

Then we will log into a live expert panel discussion straight from NASA. This is exclusive to host sites only, and guests are welcome to submit questions in advance or during the live chat.

We will have many kid activities throughout the day both inside and out (weather permitting). This is a great chance for kids of all ages to further their interest in astronomy, science, and the James Webb Space Telescope, and have loads of fun doing it!

Food and refreshments will be provided. Join the activities, visit the new Webb-related displays, walk around the grounds and chat with our members. All ages are welcome to this free event exploring Webb and the wonders of our universe.

August 20th 2022, 8:00 PM

This event will be held in person as well as Zoom

Title: The First Stars

Presenter: Brent Studer, Kirkwood Community College

Carl Sagan once said, “If you wish to make an apple pie from scratch, you must first invent the Universe.” Indeed, nearly every chemical element found in all the ingredients needed to make that pie are the product of an eons-long chain of events set in place by stars as they evolve. However, at the beginning of cosmic time there were no stars. Understanding when and how those first stars formed, and how they influenced the formation of the first galaxies is not well understood. Astronomers have hypotheses and models and now the James Webb Space Telescope, which is uniquely designed to help answer questions about the evolution of the early universe and perhaps even those first stars. Tonight, we’ll talk about what those first stars might have been like and what answers JWST and the newest generation of tools might provide about this mysterious time in the universe’s evolution.


 September 17th 2022, 7:30 PM


This event will be held in person as well as Zoom

 Title: Holding a mirror to the nighttime Ionosphere: How we do it and what we see.


Summary: The night sky shows us glowing bodies in the universe as far as our eyes can see.
It hardly occurs to us then that the earth is also glowing at night. The 'nightglow' or 'airglow' as we know it, is made up of several glowing layers of light and can be viewed with cameras on satellites or on the ground. In this presentation, we will talk about what causes the airglow, and what we can learn about the earth's upper atmosphere by studying these airglow layers. We will talk about a large-scale effort supported by the National Science Foundation to image multiple airglow layers from the ground continuously, allowing us to observe the chaotic nighttime upper atmosphere. 
Bio: Dr. Asti Bhatt is a geospace scientist at SRI International in California and studies the interaction between the sun, the earth's plasma environment, and the earth's lower atmosphere. She builds and uses imaging systems across the continental United States to observe the emissions from the earth's upper atmosphere, and manages operations and maintenance of ionospheric radars in Alaska and northern Canada on the National Science Foundation awards. 

October 1st 2022,7:30 PM - InOMN - International Observe the Moon Night

This event will be held in person as well as Zoom

 Title: Lunar Landscapes

Presenter: Mr. Doug Slauson

"In recognition of the International Observe the Moon Night, we will
consider what to look for, where to look, and what to use when observing
the moon. We will examine a brief history of the first telescopic
observations of the moon and the naming of its features.  Also, we will
consider the first telescopes used to study the moon and which
instruments are appropriate for today's backyard observer when
observing the moon. Weather permitting, we will use the observatory's
telescopes to examine the moon and some of the features highlighted
during the presentation. If the clouds don't gather overhead, the lunar
views will be stunning."


October 15th 2022, 7:30 PM

This event will be held in person as well as Zoom

 Title: Telling Time by the Stars

Presenter: Professor Steven Spangler, University of Iowa Physics and Astronomy

Most people use their phones when they want to know the time of day.  The same is true for the day of year.  However, time within the day and during the year are fundamentally astronomical concepts.  Human societies throughout history used observations of the Sun, Moon, and stars to tell them the date during the year, and the time during the day and night.  In this talk, I will describe the astronomical basis of date and time, and show how we can still use observations of the sky to tell us these things.  I will talk about the "Polaris-Kochab clock" as a way of telling time at night without looking at your phone!  If it is clear, we will try it out at the observatory's outdoor planetarium after the talk. 





Public observing events are held in the Eastern Iowa Observatory and Learning Center at the Palisades-Dows Observatory and Preserve through a generous agreement with the Linn County Conservation Department. For directions, please visit our Map to Pal-Dows page or download a pdf version (276 kB.)

The Cedar Amateur Astronomers, Inc. is a participating member of Night Sky Network.