Episode 226

In this episode, we’re turning our eyes toward some of the most dynamic travelers in our solar system — comets — and looking ahead to what promises to be an exciting year in the night sky: 2026.

Each year brings a new lineup of these icy visitors, and with them, the chance for both amateur and professional observers to witness spectacular changes as they approach the Sun and develop tails of gas and dust. But which comets will stand out in 2026? Which ones might become visible to the naked eye — and which could surprise us?

To help answer those questions, I’m joined by Carl Hergenrother, Coordinator of the ALPO Comets Section and a veteran comet discoverer himself — yes, he even has one named after him, Comet 168P/Hergenrother. Carl has spent decades studying, imaging, and analyzing comets from both professional observatories and backyard telescopes.

Together, we’ll explore which comets are expected to light up the sky in 2026, how to observe them, and what role amateur astronomers can play in monitoring these fascinating objects.

So grab your star charts, check your observing gear, and get ready — we’re about to dive into “Comets of 2026” with Carl Hergenrother.

You can contact Carl at:

ALPO Comets Section

https://www.alpo-astronomy.org/Comets

For more information you can visit the ALPO web site at:

www.alpo-astronomy.org/

You can also support this podcast at Patreon:

https://www.patreon.com/ObserversNotebook

Listen to the podcast on Soundcloud:

https://soundcloud.com/observersnotebook

Subscribe on our YouTube Channel:

https://www.youtube.com/c/AssociationofLunarandPlanetaryObservers

Subscribe on iTunes:

https://itunes.apple.com/us/podcast/observers-notebook-the-alpo-podcast/id1199301885?mt=2

I want to thank the Producers of this podcast, Steve Siedentop and Michael Moyer for their generous support of the Observers Notebook.

Our Patreons:

Jerry White

Jason Inman

Bob Lunsford

Steve Seidentop

Stephen Bennett

Michael Moyer

Shawn Dilles

Damian Allis

Carl Hergenrother

Michael McShan

Michael Blake

Nick Evetts

Stan Sienkiewicz

Carl Hergenrother

Stan Sienkiewicz

John Rogers

Jim McCarthy

Stanley McMahan

Episode 225

In this episode of the Observers Notebook Podcast, host Tim Robertson talks with Roger Venable, the ALPO Mars Coordinator and President of the International Occultation and Timing Association (IOTA).

They discuss the mission of IOTA, the important work the organization does in observing and timing occultations, and how listeners can get involved in this fascinating field of astronomical research.

You can contact Roger at:

IOTA Website

https://occultations.org/

IOTA Group

https://groups.io/g/IOTAoccultations

For more information you can visit the ALPO web site at:

www.alpo-astronomy.org/

You can also support this podcast at Patreon:

https://www.patreon.com/ObserversNotebook

Listen to the podcast on Soundcloud:

https://soundcloud.com/observersnotebook

Subscribe on our YouTube Channel:

https://www.youtube.com/c/AssociationofLunarandPlanetaryObservers

Subscribe on iTunes:

https://itunes.apple.com/us/podcast/observers-notebook-the-alpo-podcast/id1199301885?mt=2

I want to thank the Producers of this podcast, Steve Siedentop and Michael Moyer for their generous support of the Observers Notebook.

Our Patreons:

Jerry White

Jason Inman

Bob Lunsford

Steve Seidentop

Stephen Bennett

Michael Moyer

Shawn Dilles

Damian Allis

Carl Hergenrother

Michael McShan

Michael Blake

Nick Evetts

Stan Sienkiewicz

Carl Hergenrother

Stan Sienkiewicz

John Rogers

Jim McCarthy

Stanley McMahan

“Unveiling Uranus: The Ice Giant in the Amateur’s Eye”

How backyard observers are helping unlock the mysteries of Uranus.

Episode 224

In this episode of the Observers Notebook Podcast, host Tim Robertson talks with Richard Schmude, the ALPO Uranus Section Coordinator, about how amateur astronomers are playing a vital role in unraveling the mysteries of Uranus, the distant ice giant of our Solar System.

They discuss the latest observations, imaging techniques, and brightness studies that are helping to expand our understanding of this often-overlooked planet. Learn how backyard telescopes, patience, and dedication are contributing to professional research—and how you can get involved in observing Uranus through the Association of Lunar and Planetary Observers (ALPO).

You can contact Richard at:

For more information you can visit the ALPO web site at:

www.alpo-astronomy.org/

You can also support this podcast at Patreon:

https://www.patreon.com/ObserversNotebook

Listen to the podcast on Soundcloud:

https://soundcloud.com/observersnotebook

Subscribe on our YouTube Channel:

https://www.youtube.com/c/AssociationofLunarandPlanetaryObservers

Subscribe on iTunes:

https://itunes.apple.com/us/podcast/observers-notebook-the-alpo-podcast/id1199301885?mt=2

I want to thank the Producers of this podcast, Steve Siedentop and Michael Moyer for their generous support of the Observers Notebook.

Our Patreons:

Jerry White

Jason Inman

Bob Lunsford

Steve Seidentop

Stephen Bennett

Michael Moyer

Shawn Dilles

Damian Allis

Carl Hergenrother

Michael McShan

Michael Blake

Nick Evetts

Stan Sienkiewicz

Carl Hergenrother

Stan Sienkiewicz

John Rogers

Jim McCarthy

Stanley McMahan

Episode 223

Don’t Miss the Show: The Geminids Light Up December 2025

In this episode of the Observers Notebook Podcast, host Tim Robertson welcomes Bob Lunsford, Meteor Coordinator for the Association of Lunar and Planetary Observers (ALPO), to discuss the upcoming Geminids Meteor Shower.

They explore what makes the Geminids one of the most reliable and spectacular meteor displays of the year, including tips on when and where to observe, expected activity rates, and how to record your observations for ALPO’s Meteor Section.

Whether you’re a seasoned observer or just beginning your stargazing journey, this episode will help you make the most of this dazzling celestial event.

You can contact Bob at:

American Meteor Society

https://www.amsmeteors.org/meteor-showers/meteor-shower-calendar/

For more information you can visit the ALPO web site at:

www.alpo-astronomy.org/

You can also support this podcast at Patreon:

https://www.patreon.com/ObserversNotebook

Listen to the podcast on Soundcloud:

https://soundcloud.com/observersnotebook

Subscribe on our YouTube Channel:

https://www.youtube.com/c/AssociationofLunarandPlanetaryObservers

Subscribe on iTunes:

https://itunes.apple.com/us/podcast/observers-notebook-the-alpo-podcast/id1199301885?mt=2

I want to thank the Producers of this podcast, Steve Siedentop and Michael Moyer for their generous support of the Observers Notebook.

Our Patreons:

Jerry White

Jason Inman

Bob Lunsford

Steve Seidentop

Stephen Bennett

Michael Moyer

Shawn Dilles

Damian Allis

Carl Hergenrother

Michael McShan

Michael Blake

Nick Evetts

Stan Sienkiewicz

Carl Hergenrother

Stan Sienkiewicz

John Rogers

Jim McCarthy

Stanley McMahan

Episode 222

In this episode of The Observers Notebook Podcast, host Tim Robertson sits down with Alberto Anunziato, an ALPO Lunar Observer from Argentina. Together, they explore the fascinating intersection between art and science in lunar observation — how detailed sketches made at the eyepiece can capture fleeting features of the Moon, aid in scientific study, and preserve the personal experience of observation.

Is sketching an artistic pastime or a scientific tool? Alberto shares his insights, techniques, and passion for visual recording of lunar phenomena, reminding us that even in the digital age, a sketch can reveal what a camera may miss.

You can contact Alberto at:

For more information you can visit the ALPO web site at:

www.alpo-astronomy.org/

You can also support this podcast at Patreon:

https://www.patreon.com/ObserversNotebook

Listen to the podcast on Soundcloud:

https://soundcloud.com/observersnotebook

Subscribe on our YouTube Channel:

https://www.youtube.com/c/AssociationofLunarandPlanetaryObservers

Subscribe on iTunes:

https://itunes.apple.com/us/podcast/observers-notebook-the-alpo-podcast/id1199301885?mt=2

I want to thank the Producers of this podcast, Steve Siedentop and Michael Moyer for their generous support of the Observers Notebook.

Our Patreons:

Jerry White

Jason Inman

Bob Lunsford

Steve Seidentop

Stephen Bennett

Michael Moyer

Shawn Dilles

Damian Allis

Carl Hergenrother

Michael McShan

Michael Blake

Nick Evetts

Stan Sienkiewicz

Carl Hergenrother

Stan Sienkiewicz

John Rogers

Jim McCarthy

Stanley McMahan

Episode 221

In this episode of the Observers Notebook podcast, host Tim Robertson talks to Bob Lunsford about the upcoming Orionids, Taurids, and Leonid’s Meteor Showers.

You can contact Bob at:

American Meteor Society

https://www.amsmeteors.org/meteor-showers/meteor-shower-calendar/

For more information you can visit the ALPO web site at:

www.alpo-astronomy.org/

You can also support this podcast at Patreon:

https://www.patreon.com/ObserversNotebook

Listen to the podcast on Soundcloud:

https://soundcloud.com/observersnotebook

Subscribe on our YouTube Channel:

https://www.youtube.com/c/AssociationofLunarandPlanetaryObservers

Subscribe on iTunes:

https://itunes.apple.com/us/podcast/observers-notebook-the-alpo-podcast/id1199301885?mt=2

I want to thank the Producers of this podcast, Steve Siedentop and Michael Moyer for their generous support of the Observers Notebook.

Our Patreons:

Jerry White

Jason Inman

Bob Lunsford

Steve Seidentop

Stephen Bennett

Michael Moyer

Shawn Dilles

Damian Allis

Carl Hergenrother

Michael McShan

Michael Blake

Nick Evetts

Stan Sienkiewicz

Carl Hergenrother

Stan Sienkiewicz

John Rogers

Jim McCarthy

Stanley McMahan

Episode 102025

In this episode of the Observers Notebook podcast, host Tim Robertson talks to the ALPO Comets Section Coordinator Carl Hergenrother.

Carl comes on the podcast to discuss Comet Lemmon and Swan.

You can contact Carl at:

ALPO Comets Section blog:

http://www.alpo-astronomy.org/cometblog/

In the Sky- Guides to the night sky

https://in-the-sky.org/

For more information you can visit the ALPO web site at:

www.alpo-astronomy.org/

You can also support this podcast at Patreon:

https://www.patreon.com/ObserversNotebook

Listen to the podcast on Soundcloud:

https://soundcloud.com/observersnotebook

Subscribe on our YouTube Channel:

https://www.youtube.com/c/AssociationofLunarandPlanetaryObservers

Subscribe on iTunes:

https://itunes.apple.com/us/podcast/observers-notebook-the-alpo-podcast/id1199301885?mt=2

I want to thank the Producers of this podcast, Steve Siedentop and Michael Moyer for their generous support of the Observers Notebook.

Our Patreons:

Jerry White

Jason Inman

Bob Lunsford

Steve Seidentop

Stephen Bennett

Michael Moyer

Shawn Dilles

Damian Allis

Carl Hergenrother

Michael McShan

Michael Blake

Nick Evetts

Stan Sienkiewicz

Carl Hergenrother

Stan Sienkiewicz

John Rogers

Jim McCarthy

Stanley McMahan

Episode 220

In this episode of the Observers Notebook podcast, host Tim Robertson talks to the Director of Astronomy Outreach for the International Astronomical Union, Kelly Blumenthal.

You can contact Kelly at:

International Astronomical Union:

https://www.iau.org/

https://iau.org/WG330/WG330/Home.aspx

iauoutreach.org

For more information you can visit the ALPO web site at:

www.alpo-astronomy.org/

You can also support this podcast at Patreon:

https://www.patreon.com/ObserversNotebook

Listen to the podcast on Soundcloud:

https://soundcloud.com/observersnotebook

Subscribe on our YouTube Channel:

https://www.youtube.com/c/AssociationofLunarandPlanetaryObservers

Subscribe on iTunes:

https://itunes.apple.com/us/podcast/observers-notebook-the-alpo-podcast/id1199301885?mt=2

I want to thank the Producers of this podcast, Steve Siedentop and Michael Moyer for their generous support of the Observers Notebook.

Our Patreons:

Jerry White

Jason Inman

Bob Lunsford

Steve Seidentop

Stephen Bennett

Michael Moyer

Shawn Dilles

Damian Allis

Carl Hergenrother

Michael McShan

Michael Blake

Nick Evetts

Stan Sienkiewicz

Carl Hergenrother

Stan Sienkiewicz

John Rogers

Jim McCarthy

Stanley McMahan

Episode 219

In this episode of the Observers Notebook podcast, host Tim Robertson talks to Bob Lunsford about his process for observing and photographing the recent transits of Saturn’s moon Titan.

Titan’s Orbit and Motion:

• Orbital period around Saturn: ~15.945 Earth days

• Average distance from Saturn: ~1.22 million km

• Orbital inclination: ~0.3° relative to Saturn’s equator (small, so Titan’s path is nearly aligned with Saturn’s rings).

• Apparent size: ~0.8 arcseconds (tiny, only detectable as a “point” in most telescopes).

• Shadow transits are possible only when Saturn’s rings are edge-on (every ~15 years).

• September 20, 2025 — Start around 5:09 AM UTC (≈10:09 PM PDT); ends ~7:34 AM UTC (~12:34 AM PDT); Titan may also be visible near its shadow.

• After October 5–6, 2025, this spectacular phenomenon won’t happen again until 2038–2039.

You can contact Bob at:

Stellarium

https://stellarium.org/

For more information you can visit the ALPO web site at:

www.alpo-astronomy.org/

You can also support this podcast at Patreon:

https://www.patreon.com/ObserversNotebook

Listen to the podcast on Soundcloud:

https://soundcloud.com/observersnotebook

Subscribe on our YouTube Channel:

https://www.youtube.com/c/AssociationofLunarandPlanetaryObservers

Subscribe on iTunes:

https://itunes.apple.com/us/podcast/observers-notebook-the-alpo-podcast/id1199301885?mt=2

I want to thank the Producers of this podcast, Steve Siedentop and Michael Moyer for their generous support of the Observers Notebook.

Our Patreons:

Jerry White

Jason Inman

Bob Lunsford

Steve Seidentop

Stephen Bennett

Michael Moyer

Shawn Dilles

Damian Allis

Carl Hergenrother

Michael McShan

Michael Blake

Nick Evetts

Stan Sienkiewicz

Carl Hergenrother

Stan Sienkiewicz

John Rogers

Jim McCarthy

Stanley McMahan

Episode 218

In this episode of the Observers Notebook podcast, host Tim Robertson talks to the Director of International Observe the Moon Night, Staci Horvath.

You can contact Staci at:

International Observe the Moon Night:

https://moon.nasa.gov/observe-the-moon-night/

For more information you can visit the ALPO web site at:

www.alpo-astronomy.org/

You can also support this podcast at Patreon:

https://www.patreon.com/ObserversNotebook

Listen to the podcast on Soundcloud:

https://soundcloud.com/observersnotebook

Subscribe on our YouTube Channel:

https://www.youtube.com/c/AssociationofLunarandPlanetaryObservers

Subscribe on iTunes:

https://itunes.apple.com/us/podcast/observers-notebook-the-alpo-podcast/id1199301885?mt=2

I want to thank the Producers of this podcast, Steve Siedentop and Michael Moyer for their generous support of the Observers Notebook.

Our Patreons:

Jerry White

Jason Inman

Bob Lunsford

Steve Seidentop

Stephen Bennett

Michael Moyer

Shawn Dilles

Damian Allis

Carl Hergenrother

Michael McShan

Michael Blake

Nick Evetts

Stan Sienkiewicz

Carl Hergenrother

Stan Sienkiewicz

John Rogers

Jim McCarthy

Stanley McMahan