Showing Off the Solar System To Young School Groups
(and Occultation Adventures in the Solar System)
with Richard Nolthenius
Video LINK
Below you can find a list of attendees, a copy of the chat, and an AI summary.
To see a description and schedule of all upcoming Planetarians' Zoom Seminars, visit https://www.ppadomes.org/events/online-seminars/pzs-schedule
Date and time for the next seminar:
Planetarium Educators Workshop, Module 2: A Framework for Examining Planetarium Programs, with Alan Gould. 2025 Nov 21 (3rd Friday) at 2pm PDT (5pm EDT, 22:00 UT).
Attendees
Chat
AI-generated Summary
Rosemary Walling (co-host), Marie Drake Planetarium, Juneau, Ak
Mary Holt (co-host), Berkeley, California
Andrew Buckingham, Auckland, New Zealand
Guilherme Frederico Marranghello, Bagé, Brazil.
Jeff Nee, Pasadena, CA
Karl von Ahnen Santa Cruz Mountains, California
Cristina Della Rosa, Marie Drake Planetarium
and a few more
(The timestamps below are roughly 30 minutes ahead of the corresponding times in the video. )
00:37:51 From Karl von Ahnen": Excellent, Rick! Very sorry I have to leave early. I will watch the video recording.
00:42:39 Jeff Nee: Double Asteroid Redirection Test
00:43:46 Guilherme Frederico Marranghello: I googled "Dart mission" and it really collided with the browser.
From Rosemary Walling (PPA): You're right!
00:56:21 From Mary Holt: Apologies if you already said this at the beginning - but how much of this presentation is what you show in planetarium shows and how much was just for this presentation?
00:59:44 From Guilherme Frederico Marranghello: I have to leave. Thanks for the talk! Have a great weekend!
00:03:36 From Mary Holt: Well a lot of the images in planetarium software are actual photos to be fair
00:15:22 Nick Strobel: Thank you for the talk!
0015:55 From Amie Gallagher: Thanks for the talk!
This AI-generated summary has not been edited for accuracy nor does not replace watching the full video. If you find any incorrect or misleading information in the AI summaries, you can let us know. Our contact information is here.
This presentation focused on planetarium education techniques and asteroid occultation research. Rick Nolthenius, Department Chair of Astronomy at Cabrillo College, shared his approach to engaging young audiences in a basic A3P planetarium and discussed his professional work studying asteroids through occultation observations. The talk demonstrated how to create engaging educational experiences with limited equipment while also highlighting the scientific value of asteroid occultation research for determining asteroid properties and supporting NASA missions.
Interactive planetarium education techniques for engaging young audiences
Asteroid occultation methodology for determining asteroid properties
Binary asteroid systems and their scientific importance
Kuiper Belt object research, including rings and moons around Quaoar
Practical applications of occultation data for NASA missions
How can planetarium educators create engaging experiences with limited equipment?
What scientific value do asteroid occultations provide that even large telescopes cannot?
How do binary asteroids help determine composition and density of asteroids?
Why do some objects like Quaoar have rings beyond the Roche limit when theory suggests they shouldn't exist?
How can amateur astronomers contribute to high-value scientific research?
Engaging planetarium shows can be created through interactive presentation styles and colorful visuals even with basic equipment
Asteroid occultation observations provide higher precision measurements than even the largest telescopes can achieve
Binary asteroid systems allow for mass calculations that help determine asteroid composition
Occultation data directly supports NASA missions by providing precise positioning and identifying potential hazards
Amateur astronomers with modest equipment can contribute meaningful data to planetary science
Rick Nolthenius described his approach to planetarium education at Cabrillo College using a basic A3P planetarium system from the 1950s with minimal special effects. Despite equipment limitations, he creates engaging shows through personal interaction, walking around the planetarium and directly engaging students with questions. His presentations focus on colorful, visually striking images of the solar system, tailored to different age groups but primarily elementary school students. The shows typically begin with 5 minutes of stars and music to allow for dark adaptation, followed by demonstrations of celestial motion and then a tour of the solar system with carefully selected images that spark curiosity. Rick emphasized making astronomy relatable by connecting cosmic phenomena to students' experiences, such as comparing Venus's surface to Hawaii's lava fields or describing Mercury's shrinkage like a "raisin in the sun." He noted that while adults might expect more special effects, children respond well to this interactive approach.
Relevant Q&A
Rosemary: How much iteration have you done over the years to refine your presentation, and how do you make variations for different age groups?
Rick: I primarily get elementary school groups but occasionally junior high or high school students. I update photos when new missions provide cool images, and I ask groups if there's something specific they want to see. My standard show is the solar system because it's relatable to non-specialists.
Rosemary: Do you do any photo editing to bring out colors more than what's straight off the image?
Rick: Sometimes I use Photoshop to enhance colors, but I try not to go overboard. Most images are already processed by JPL, so I mainly size and crop them
Rick detailed his work studying asteroids through occultation observations, where asteroids briefly block the light from distant stars. This technique provides extremely precise measurements of asteroid size, shape, and position—often more accurate than what can be obtained with the world's largest telescopes. The methodology involves using specialized equipment including a video time inserter that timestamps video frames with GPS precision, allowing measurements down to 1/10,000th of a second. By combining observations from multiple locations along an occultation path, researchers can map asteroid outlines with remarkable precision. Rick described several significant occultation campaigns, including observations of the asteroid Phaethon (parent body of the Geminid meteor shower) and the Didymos/Dimorphos system that was the target of NASA's DART mission. These observations provide critical data for mission planning and help determine asteroid properties. The discovery of binary asteroids through occultations is particularly valuable as it allows for mass calculations using Kepler's Third Law, which when combined with size measurements yields density information that reveals composition.
Relevant Q&A
Jeff: Have you ever tried exoplanet transits?
Rick: We did try one with a UCSC professor who came to Cabrillo because we had the right gear, but we got clouded out.
Jeff: How much does your occultation rig cost?
Rick: Altogether about $2,500, but prices have increased. The telescope alone (Celestron 8SE) is now about $2,000. There's now a more efficient system called Astrid available for about $800 that includes the camera, recording gear, and GPS.
Relevant Q&A
Jeff: Have you ever tried exoplanet transits?
Rick: We did try one with a UCSC professor who came to Cabrillo because we had the right gear, but we got clouded out.
Jeff: How much does your occultation rig cost?
Rick: Altogether about $2,500, but prices have increased. The telescope alone (Celestron 8SE) is now about $2,000. There's now a more efficient system called Astrid available for about $800 that includes the camera, recording gear, and GPS.
Exoplanet Watch program run out of Goddard Space Flight Center was mentioned as a citizen science opportunity similar to occultation work
Astrid system was recommended as an efficient equipment package for occultation observations, costing about $800
A forthcoming paper in the Astrophysical Journal Letters about the discovery of a new moon around Quaoar was mentioned.