#749: Dark Energy Changing Over Time

We thought Dark Energy was constant, but new results from DESI say maybe not, and if it wasn’t the Hubble Tension would be easier to solve.

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Fraser Cain
Universe Today

Dr. Pamela Gay
CosmoQuest

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18 Seasons

700+ Episodes

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#736: Gift Guide 2024

#736: Gift Guide 2024

It’s time for our Holiday Gift Guide, where we suggest ideas for presents for the space fans in your life! What books are we reading? What games are we playing and what telescopes are we admiring?

#735: Albert Einstein

#735: Albert Einstein

Last week we talked about the Einstein probe. So this week it is only natural that we talk about the man himself, Albert Einstein. He revolutionized the field of physics, played a vital role in the early 20th century and struggled to unite the forces of the Universe...

#734: The Einstein Probe

#734: The Einstein Probe

Another day, another space telescope! Today we’re looking at the newly launched Einstein Probe

#733: Euclid of Alexandria

#733: Euclid of Alexandria

Let’s look at the Euclid of Alexandria, the father of geometry and his contributions in celestial mechanics and orbital calculations.

Recent Episodes

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Jupiter’s Great Red Spot is one of its most iconic features, first seen hundreds of years ago. Although it’s certainly long-lasting, it’s been changing in size over the last few decades, shrinking and changing in color. Is it fading away? And what can the changes tell...

Ep. 690: Climate on Mars – From Ice Caps to Dust Storms

We’ve looked at Earth’s changing climate, now let’s see what it’s like for another world: Mars. Much looks familiar, but some of it is totally alien, from ice caps of frozen carbon dioxide to planetary dust storms that can obscure the entire world from view....

Ep. 689: Our Warming World – 20 Years of Climate Science

It’s official! June and July were the warmest we’ve seen since records began over a century ago. Fires are rampant across Canada, and we’re seeing record droughts around the world. Today, we’re going to look at 20 years of climate science, how well does reality match...

Ep. 688: What’s Next? Looking Ahead to Season 17

Once again, we’ve reached the end of a season here on Astronomy Cast, and it’s time for the summer hiatus. But the Universe never takes a break. What can we expect to happen over the summer while we’re catching up on our reading, building our gardens and planning for...

Ep. 687: Prepping for the Moon

We’re going back to the Moon. In the next few years humans will set foot on the Moon again, ideally this time to stay. But this will be different than the Apollo era, going to the scientifically fascinating, and difficult southern pole of the Moon. What needs to be...

Ep. 686: Ice in the Shadows

The permanently shadowed craters on the Moon are the focus of so much research. That’s because they seem to contain vast reserves of water ice. Water we could use for oxygen, propellant and so much more, but also, to help us understand where the Earth’s water came...

Ep. 685: Manufacturing in Space

Launching satellites from Earth is counter-productive. You’ve got to make a satellite that can handle Earth gravity, then the brutal flight to space, then deployment in orbit. What if you could build your spacecraft in space?...

Ep. 683: Cosmic Dawn

After the cosmic microwave background radiation was released, the Universe returned to darkness, cloaked in this clouds of primordial hydrogen and helium. Gravity pulled these vast clouds into the first stars, and then the first galaxies. This is Cosmic Dawn, and JWST...

Ep. 682: Ultra-Diffuse Galaxies and Dark Matter

Astronomers first noticed the strange behaviors of rotating galaxies almost 100 years ago, suggesting there’s an invisible dark matter hold them together with gravity. Or maybe we just don’t understand how gravity works at the largest scales. Observations are much...

Ep. 681: Kilonovae

In 2017, astronomers detected the gravitational waves and electromagnetic radiation from colliding neutron stars. This had been long theorized as one of the causes of a certain type of gamma-ray burst. By studying the event and its afterglow, astronomers have learned...

Ep. 680: Rogue Black Holes

Last week we talked about rogue stars. This week we’re going to take things up a notch and talk about an even more extreme event. Rogue black holes. Astronomers recently discovered a supermassive black hole on an escape trajectory, leaving newly forming stars in its...

Ep. 679: High(per) Velocity Stars

Most stars in the Milky Way are trapped in here with us, doomed to orbit around and around and around. But a few have found a way out, an escape into the freedom of intergalactic space. How do stars reach escape velocity, never to return?...

Ep. 678: World Building: Planet Formation, Growth, & Ejection

Okay sci-fi writers, today we’re going to give you a guided tour of building planets. How they form, how they grow, and how things can go horribly horribly wrong. https://www.youtube.com/watch?v=zJQ3BnCYiR4 Transcript (This is an automatically generated transcript)...

Ep. 677: The Answer is Always Dust

Whenever astronomers discover something surprising, the answer often turns out to be dust. Dust obscuring our view, dust changing the polarity, dust warming things up, dust cooling things down. It’s always dust. Until it isn’t....

Ep. 676: Other Things with Rings

We’ve spent a lot of time gushing about Saturn’s rings, but there are other places with ring systems. And not just Jupiter and the ice giants, but asteroids, dwarf planets, centaurs and even exoplanets. Today we’ll gush about them....

Ep. 675: Exotic Forms of Ice

Ice is ice, right? You know, what you get when water freezes. Well, maybe here on Earth. But across the Universe, water can be squeezed together at different temperatures and pressures, leading to very different structures. Today we’ll talk about the different forms...

Ep. 674: Asteroid Early Warning Systems

The asteroid apocalypse is one of those existential crises that keep astronomers up at night. But the DART mission showed us that we can push an asteroid off its trajectory if we have enough warning. Today we’ll talk about how humanity is building early warning...

Ep. 673: How to See Satellites (or Avoid Seeing Them)

If you’re in dark skies and look up, you’re certain to see a satellite. Lots of them. But how can you know which one you’re seeing, and how can you improve your chances of a sighting? Today we’ll talk about how to see satellites, or avoid seeing them....

Ep. 672: Space Debris Removal

We’ve talked about the rising problem of space junk. Okay, we know it’s an issue. So what can be done about it? Today we’ll talk about ideas to remove space junk, making sure space is open to use for the centuries to come. https://www.youtube.com/watch?v=Q7RxmX5eDY4...