A young observer peers through the CAA's vintage Celestron 16 telescope.
PUBLIC EVENTS
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
2025 Presentations
April 26th 2025 - 8:00 -This event will be held in person as well as on Zoom
Title: What Causes the Northern Lights and How to Predict When They will Occur
Presenter: Jodie McLennan, graduate research assistant - University of Iowa
The northern lights, also called the aurora borealis, have been recently widely sighted due to a peak in the Sun's activity cycle (even in Iowa!). In this talk you will hear about what causes the northern lights and what it can tell us about the dynamics of energetic particles in the near-Earth space environment. There are publicly available tools online that can help us predict when and where we see the aurora. Oftentimes media sources will over-promise the extent to which we can see aurora events, though it can be difficult even with the data to know exactly when we will see the northern lights. We will go over how to use these tools and their limitations so that you can predict for yourself when is the best time to go out and see the aurora!
Join Zoom Meeting
https://us06web.zoom.us/j/87660253106?pwd=itbgVEyU9sLrca6P6bcv7axBqI7RGi.1
Meeting ID: 876 6025 3106
Passcode: 816770
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Meeting ID: 876 6025 3106
Passcode: 816770
Find your local number: https://us06web.zoom.us/u/kdJrCgDcUh
May 17th 2025 - 8:30 -This event will be held in person as well as on Zoom
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Presenter: University of Iowa Prof. Hai Fu
June 14th 2025 - 8:30 -This event will be held in person as well as on Zoom
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Presenter: University of Iowa Professor David Nataf
June 28th 2025 - 8:30 -This event will be held in person as well as on Zoom
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Presenter: Professor Brent Studer, Kirkwood Community College
July 12th 2025 - 3-6PM - Solar Saturday -This event will be held in person as well as on Zoom
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Presenter: Carl Bracken CAA volunteer and active member since 1995 and Basepoint Building Automations Security Systems Consultant
July 26th 2025 - 8:30 -This event will be held in person as well as on Zoom
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Presenter: Professor Allison Jaynes - University of Iowa
August 16th 2025 - 8:00 -This event will be held in person as well as on Zoom
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September 13th 2025 - 7:30 -This event will be held in person as well as on Zoom
Title: A Photo of the Whole Sky: the Story of the Palomar Observatory Sky Survey
Presenter: Professor Steven Spangler - Professor Emeritus - University of Iowa
When we look at the night sky from a dark location we can see a big range in the brightness of stars. From the Eastern Iowa Observatory and Learning Center (EIOLC), the energy per second coming through our eyes from the faintest stars is only about 1/100 that of the brightest stars. What would happen if we could see stars 100 times fainter still, and then another factor of 100, and so on? The sky also contains glowing objects that are obviously not stars, but to the casual observer, it is not obvious what they are. How many of these could we see if we could go down in brightness by the same amount? Answering these questions has been a goal of astronomy over the last two to three centuries. A major development occurred in the late 1940s and early 1950s, when sensitive photos were made of the whole sky visible from southern California. This Palomar Observatory Sky Survey (POSS) was a major research tool for decades, and permitted many important discoveries. The University of Iowa has had a copy of this survey since the 1950s. Recently, the University generously allowed us to host this collection at the EIOLC. In this talk, I will describe how the POSS was carried out and describe some of the discoveries made with it. Audience members will be able to see the collection after the talk.
October 4th 2025 - 7:30 - InOMN -This event will be held in person as well as on Zoom
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Presenter: Trena Johnson - Former Minnesota Astronoical Society president
October 25th 2025 - 7:30 -This event will be held in person as well as on Zoom
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November 15th 2025 - 7:30 -This event will be held in person as well as on Zoom
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December 13th 2025 - 7:30 - Virtual only
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* Note: Virtual only. Observatory closed due to winter driving conditions.
Past Presentations
March 22nd 2025 - 7:30 -This event will be held in person as well as on Zoom
Title: A Close Look at the Planet Mars
Presenter: Professor Steven Spangler - Professor Emeritus - University of Iowa
Mars is one of the four "terrestrial planets" in the solar system that approximately resemble the Earth. Every two years, it comes especially close to the Earth in a configuration called "opposition". Opposition this year was on January 16, so we are about two months past that date. Nonetheless, Mars is closer than it usually is, and it is perfectly located for observing in the evening sky. In this talk I will describe where Mars is in space, and how that location affects its properties. I will also describe the ongoing spacecraft exploration of Mars, and all the amazing things we have learned about the "Red Planet" in the last fifty to sixty years.
Meeting recording:
Passcode: !133+rY9
Meeting Summary for A Close Look at the Planet Mars
Mar 22, 2025 07:01 PM Central Time (US and Canada) ID: 814 0471 8701
Quick recap
EIOLC discussed the Eastern Iowa Observatory and Learning Center's funding sources, membership benefits, and upcoming events, while also sharing personal notes. The speaker then provided an overview of Mars, its visibility, and its history of observation, including the limitations of visual observations and the composition of the planet. The discussion concluded with a focus on recent Mars rover missions, their advanced capabilities, and the geological information they provide, encouraging attendees to view Mars through telescopes at the observatory.
Next steps
Cedar Amateur Astronomers to host a member night next week for viewing Mars.
Steve Spangler to potentially arrange for a University of Iowa geologist colleague to give a talk on the geology of Mars later in the year.
Attendees to view Mars through the telescopes available on site after the presentation.
Summary
Eastern Iowa Observatory Public Night
In the meeting, AlanE and EIOLC conducted a test and discussed the functionality of their system. EIOLC then welcomed everyone to the Eastern Iowa Observatory and Learning Center's first in-person public night of the year. EIOLC explained the center's funding sources, including membership dues, private group visits, grants, and donations. EIOLC also mentioned that the center is run by volunteers and offered information about membership benefits. EIOLC shared a personal note about their mother's 100th birthday and their anniversary. EIOLC also mentioned a member night next week and invited guests to attend. Finally, EIOLC introduced Mr. Steven Spangler, a University of Iowa Professor Emeritus, to give a presentation.
Mars Visibility and Oppositions Explained
The speaker discusses the planet Mars and its upcoming visibility. He explains that Mars is currently about 1.05 astronomical units from Earth, which is not the optimal viewing time. The best time to view Mars was on January 15th during its opposition, when it was closest to Earth at 0.64 astronomical units away. The speaker describes how Mars' elliptical orbit affects its distance from Earth during oppositions, which occur every 26 months. He mentions that the next very close opposition will be in September 2035, when Mars will be only 0.38 astronomical units from Earth. The talk includes a video explaining the concept of oppositions and how they relate to the orbits of Earth and Mars.
Mars Observation History and Composition
In the meeting, EIOLC discussed the history of Mars observation, starting with Percival Lowell, a wealthy Boston lawyer who established an observatory in Arizona to study Mars. EIOLC explained the limitations of visual observations through telescopes, including the potential for seeing things that aren't there. He then moved on to discuss the size and mass of Mars compared to Earth, noting that Mars is about half the size and has 11% the mass of Earth. EIOLC also touched on the composition of Mars, stating that it has a similar rocky composition to Earth but lacks a dense iron core. He concluded by mentioning the thin and carbon dioxide-rich atmosphere of Mars, which would be fatal for humans to breathe.
Mars Exploration: From Canals to Valleys
The discussion covers the historical perception of Mars and how it evolved with scientific advancements. Early beliefs about Martian canals and potential civilizations were dispelled by the Mariner 4 mission in 1965, which revealed a cratered surface similar to the Moon. Subsequent missions, however, discovered valley networks suggesting ancient water flow. By 2000, scientists faced a conundrum: Mars' current climate cannot support liquid water, yet there is evidence of water-formed landscapes from 3-4 billion years ago. The focus of Mars exploration has since shifted to landing missions, allowing geologists to analyze rock properties and soil directly on the planet's surface.
Mars Rover Missions and Observations
The speaker discusses recent Mars rover missions, particularly Perseverance and Curiosity, highlighting their advanced capabilities and autonomous landing procedures. He shows an animation of Perseverance's landing, emphasizing the spacecraft's ability to navigate and land without real-time human control due to signal delay. The speaker then describes the detailed geological information these rovers provide, including the ability to analyze rock compositions on the Martian surface. He concludes by encouraging attendees to view Mars through telescopes at the observatory, contrasting current detailed knowledge with limited observations from 60 years ago.
February 15th 2025 - 7:30 - Virtual only
Title: The Cosmic Distance Ladder
Presenter: Dave Falkner – MAS Member and NASA Solar System Ambassador
This presentation will discuss measuring the vast distances in the universe. Dave will start with the early attempts to measure distances to celestial bodies. Moving forward through history, Dave will introduce the improvements in instrumentation and discoveries made, and the use of “standard candles” which not only expanded our view of the universe but enabled us to quantify distances. Dave will wrap up by talking about some of the challenges that remain in determining distances in space.
Dave 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.
After retiring from the US Navy, Dave settled in Minnesota and became an active member of the Minnesota Astronomical Society (MAS). He has served as its President from 2011 – 2014, and 2019 – 2020, and as Secretary from 2023-2024. As a member of the MAS, Dave enjoyed performing astronomical outreach often speaking to groups at libraries, nature centers and schools.
In 2011 Dave traveled to Tucson, AZ to view the Transit of Venus at the Mount Lemmon Observatory in Tucson and visited Kitt Peak National Observatory while he was there. In 2017 he traveled to Casper, WY in 2017 and Indianapolis in 2024 to view the total eclipse of the Sun. In December 2022 Dave traveled to Chile to visit the US Research telescopes located there and became part of the Astronomy in Chile Educators Ambassador Program (ACEAP) educating the public about the telescopes and research astronomy being conducted there.
Dave is a NASA/JPL Solar System Ambassador where he educates the public about space, space exploration and NASA missions in particular. Along with his outreach activities Dave has taught beginning Astronomy classes at a local community college and has published three books; two editions of “Mythology of the Night Sky” and the book “The Stories of Astronomers and Their Stars.”
Meeting recording:
https://us06web.zoom.us/rec/share/O7WnEoHaKqgJtjTa3KofaQ1HbwVuAEnfPFeAo6iVWr_qW6r4-E8Gn4DiCIxfgxxW.EoKraHy5xiNNMWRAJanuary 18th 2025 - 7:30 - Virtual only
Title: "Science from Across the Solar System and Beyond."
Presenter: Dr. T. Joseph Lazio, Jet Propulsion Laboratory
Almost all of the images of planets, and many of the images from the Universe beyond, obtained by NASA’s spacecraft are able to be seen only because of NASA’s Deep Space Network. Much more than just a critical part of NASA’s missions, the Deep Space Network is a science instrument in its own right. In this presentation, I will provide a brief introduction both to the Deep Space Network and some of the science results obtained from it.
Recorded meeting: https://us06web.zoom.us/rec/share/O7t9mbjAQRFGSiKGrjFBantMgI1fcRhhtBWIikV6UJE5KGB-ev9k88VnaXaSJIzV.vwykFwSB5eWrsD-V
Passcode: 1i9p^XsX
Dec 7, 2024 7:30 * Virtual Event Only
Title: The University Of Minnesota Students’ Practice Observatory – The Discovery, History, and Preservation of Its Equipment
Presenter: Mr. Valts Treibergs - Minnesota Astronomical Society
Nov 23, 2024 7:30 This event will be held in person as well as on Zoom
Title: The Resurrection of Voyager 1
Presenter: Professor William (Bill) Kurth - University of Iowa
This talk will address humankind's most distant explorers and their epic journey of discovery, now concentrating on the exploration of the interstellar medium, the 'stuff between the stars'. But, to tell this story, it is important to discuss the saga of keeping the two Voyagers going on their now 47-year journey to distances measured in nearly a light-day.
Oct 26, 2024 7:30
Title: How to Build a Space Mission - The Story of TRACERS
Presenter: Jasper S. Halekas, Professor of Physics and Astronomy at the University of Iowa
The upcoming Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) mission, designed and led by the University of Iowa, is currently in the final stages of integration and test before its planned launch next spring. I will describe the genesis and development of the TRACERS mission from the proposal phase through design, assembly, test, and integration. I will also outline the scientific goals of the mission and describe what we hope to learn from TRACERS about our local space neighborhood and the impact of the Sun and the solar wind on our terrestrial environment.
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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.
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