The Astroholic Explains

Why Darkness Matters

You can’t save the dark skies without convincing people it matters, and education is crucial to this. Across the world, so many are working on that specific aspect, and w

To Protect A Common Heritage

The battle against light pollution goes through policy and legislation. Certain regions of the world are actually in a better situation than you might think. While the ro

Where The Dark Skies Are

For most people, a dark enough sky can only be accessed on holiday, away from cities. There is a growing movement of astrotourism, so we look into what that’s like, and h

Vanishing Stars, Vanishing Nature, Vanishing Health

This episode of Starless focuses on the impact of light pollution. How has anthropogenic light changed the world in less than two centuries? The full impact is not comple

Fading To Black: The Dark Skies Movement

In this introductory episode, we will be talking about dark skies and light pollution in general, and what some organizations are doing to protect the night sky, as well

Concerning Space-Time

For the 2024 Christmas Special, we tackle Special Relativity and Chris's issues with time dilation and relativity in general! Link for Invisible Rainbows

What Was Egyptian Sky Iron?

Chris and I decided to find out when humans realized that meteorites came from beyond Earth: it could be a lot older than it was once thought! Egyptologist Dr Victoria Al

For How Long Have Humans Believed In Aliens?

We are talking about ancient aliens. (No, not the racist conspiracy theory!) We look into the concept of extraterrestrials over history and how it originated. Who were th

How Does Sound Spread In Space?

In this episode, we tackle the classic concept of sound in space, what can we measure, and why it is important that some sound waves move through the cosmos.

Could We Tell If We Were In A Middle Of A Galaxy Merger?

Our position inside the Milky Way doesn't give us an advantageous view of our galaxy. But that doesn't mean we haven't found a way around it. Joined by Dr GyuChul Myeong,

Can You Save A Dying Star?

In the last episode, we looked at how stars end up dead. So Chris has an important follow-up: can you find a way to heal and save a dying star? #InvisibleRainbows

Do All Stars Expand When They Die?

Our Sun and many other stars will become larger later in life. But is this a condition common to all stars? Guest questioner Francis wonders about the future of stars and

Black Diamonds Are Actually Extraterrestrials - Feat. Dr David Pegg

In this episode, we tackle the peculiar carbonado diamond, a black diamond that looks very different from the glittering gems we might be more familiar with. And we will

Can Planets Truly Have One Climate?

Planets in sci-fi are often portrayed as having a single climate, but how truthful is that idea? This audience question gets the full treatment from Alfredo & Chris as th

Hunting The Great Mexican Eclipse

Join us in this unplanned video & audio diary as we go after the April 8 total solar eclipse in Mexico. For the video version: https://youtu.be/SR00jigmgR0?si=LKLYaoqvq_Y

XS23 - Cosmicomics 100

The Astroholic Explains Xmas Special is inspired by Italo Calvino's Cosmicomics on the 100th anniversary of the author's birth. Join us for an imaginative tale, not fanta

Exclusive - Invisible Rainbows Excerpt

I'm writing a book all about the astronomy we do with the light we cannot see with our own eyes. It's called Invisible Rainbows and features astronomers from all around t

61 - What's Beyond The Edge Of The Visible Universe? - Feat Professor Peter Coles

In this episode, Alfredo and Chris are joined by cosmologist Professor Peter Coles. Together they explore the limits of the visible universe, whether finite or infinite,

60 - Before The Big Bang

We don't know and will likely never know what happened before the Big Bang, but Chris is curious about it, so we take a journey in the land before time and space!

59 - Lunacy! Or Conspiracy Theories About The Moon's Origin

Conspiracy theories and misconceptions about the Moon extend far beyond the Moon-landing! In this episode, we take a trip 4.5 billion years into the past to witness how L