Ep 488: Dark Energy: 2018 Edition

The updates continue. Last week we talked about dark matter, and this week we continue with its partner dark energy. Of course, they’re not really partners, unless you consider mysteriousness to be an attribute. Dark energy, that force that’s accelerating the expansion of the Universe. What have we learned?

Ep 487: Dark Matter: 2018 Edition

Last week, we gave you an update in particle physics. This week it’s time to see what’s new in the world of dark matter. Spoiler alert, we still have no idea what it is, but maybe a few more ideas for what it isn’t.

Updated Audio: Ep. 475: Fast Radio Bursts

Ep 475 fixed audio version – You know what’s fun? Mysteries. Here’s one: fast radio bursts. Astronomers have been detecting mysterious one-time signals from across the sky. What’s causing them? Nobody knows for sure, but the search is on to get to the bottom of them.

Ep. 475: Fast Radio Bursts

You know what’s fun? Mysteries. Here’s one: fast radio bursts. Astronomers have been detecting mysterious one-time signals from across the sky. What’s causing them? Nobody knows for sure, but the search is on to get to the bottom of them.

Ep. 397: A Universe From Nothing

One of the biggest, most basic questions you can ask is: “why is there something and not nothing?” The reality is that we don’t know the answer, we might never know the answer. Today we’ll investigate this mystery, recently covered by the physicist Lawrence Krauss in his book of the same name.

Ep. 390: Occam’s Razor and the Problem with Probabilities

I’m not saying it’s aliens, but it’s aliens. Actually, it’s almost certainly not aliens, or a wormhole, or a multiverse. When scientists discover something unusual, they make guesses about what’s happening. But Occam’s Razor encourages us to consider the probabilities of different events before making any concrete predictions.

Ep. 295: The Observable Universe

We understand our place in the Universe because of our direct observations. We can see the light that travelled billions of light years across space to reach us. This sphere of space is the observable universe; everything we can detect. But it’s really just a fraction of the larger, unobservable universe. Today, we’ll talk about both.

Ep. 179: Mysteries of the Universe, Part 2

Today we tackle more thrilling mysteries of the Universe. And by tackle, we mean, acknowledge their puzzling existence. Some mysteries will be solved shortly, others will likely trouble astronomers for centuries to come. Join us for part 2.

Ep. 178: Mysteries of the Universe, Part 1

All finished with the Milky Way, it’s time to move on to the biggest mysteries of all. The mysteries of the Universe. Let’s wonder about dark matter and dark energy, and the very nature of reality itself.

Ep. 166: Multiverses

What if our universe was just one in an infinite number of parallel universes; a possible outcome from the specific predictions of quantum mechanics. The idea of multiple universes is common in science fiction, but is there any actual science to back this theory up?

Ep. 137: Large Scale Structure of the Universe

This week we’re going to think big. Bigger than big. We’re going to consider the biggest things in the Universe. If you could pull way back, and examine regions of space billions of light-years across, what would you see? How is the Universe arranged at the largest scale? And more importantly… why?

Ep. 135: X-Ray Astronomy

We continue our journey through the electromagnetic spectrum with X-rays. If you’ve ever broken a bone, you probably know how X-rays are most commonly used. While doctors use X-rays to study the human body, and astronomers use X-rays to study some of the hottest places in the Universe. So let’s put on our X-ray specs, and see what we can see.

Ep. 134: Ultraviolet Astronomy

Our next visit in this tour through the electromagnetic spectrum is the ultraviolet. You can’t see it, but anyone who’s spent a day out in the hot sun without sunblock has sure experienced its effects. Ultraviolet radiation is associated with the birth of stars and some of the hottest places in the Universe.

Ep. 123: Homogeneity

As astronomers discovered that we live in a great big universe, they considered a fundamental question: is the universe the same everywhere? Imagine if gravity was stronger billions of light years away… Or in the past. It sounds like a simple question, but the answer has been tricky to unravel.

Ep. 122: How Old is the Universe?

We did a wildly popular three part series about the center, size and shape of the Universe. But every good trilogy needs a 4th episode. This week we look at age of the Universe. How old is the Universe, and how do we know? And how has this number changed over time as astronomers have gotten better tools and techniques?

Ep. 87: The End of the Universe Part 2: The End of Everything

Hopefully you’ve all recovered from part 1 of this set, where we make you sad about the future of the humanity, the Earth, the Sun and the Solar System. But hang on, we’re really going to bring you down. Today we’ll look far far forward into the distant future of the Universe, at timescales that we can barely comprehend.

Ep. 86: The End of the Universe Part 1: The End of the Solar System

This is a show we wanted to do since we started Astronomy Cast but we always thought it was too early. We wanted you to know that we’re positive, happy people with enthusiasm for astronomy and the future. It’s time for some sadness. It’s time for a grim look to see what the future holds for the Universe. This week we stay close to home and consider the end of humanity, the Earth, the Sun, and the entire Solar System. Next week we’ll extend out to the very end of the Universe.

Ep. 79: How Big is the Universe?

We’re ready to complete our trilogy of discovery about the universe. We’ve learned that it has no center; rather everywhere is its center and nowhere. We discovered that the universe seems to be flat. It’s not open, it’s not closed, it’s flat. If that doesn’t make any sense, you need to listen to the previous show because there’s no way I could give that an explanation.
So now we want to know: How big is it? Does it go on forever or is it finite in scale? How much of it can we see?

Ep. 78: What is the Shape of the Universe?

Some of the biggest questions in the universe depend on its shape. Is it curved? Is it flat? Is it open? Those may not make that much sense to you, but in fact it’s very important for astronomers. So which is it? How do we know? How did we figure it out? Why does it matter?

Ep. 77: Where is the Centre of the Universe?

There are some people – I’m not naming names – who think the universe revolves around them. In fact, for most of humankind, everybody thought that. It’s only been in the last few hundred years that scientists finally puzzled out that the Earth isn’t the centre of the universe at all. That begs the question: where is the centre?

Ep. 73: Questions Show #8

We’ve been so crazy following our own whims through the universe that we’ve neglected your questions. That ends today. It’s time to dig deep into our overflowing email box to retrieve the puzzling questions our listeners have sent in.

Ep. 71: Gravitational Waves

When he put together his theories of relativity, Einstein made a series of predictions. Some were confirmed just a few years later, but scientists are still working to confirm others. And one of the most fascinating is the concept of gravitational waves. As massive objects move in space, they send out ripples across the Universe that actually distort the shape of matter. Experiments are in place and in the works to detect these gravitational waves as they sweep past the Earth.

Ep. 58: Inflation

We interrupt this tour through the solar system to bring you a special show to deal with one of our most complicated subjects: the big bang. Specifically, how it’s possible that the universe could have expanded faster than the speed of light. The theory is called the inflationary theory, and the evidence is mounting to support it. Einstein said that nothing can move faster than the speed of light, and yet astronomers think the universe expanded from a microscopic spec to become larger than the solar system, in a fraction of a second.

Ep. 45: The Important Numbers in the Universe

This week we wanted to give you a basic physics lesson. This isn’t easy physics, this is a lesson on the basic numbers of the Universe. Each of these numbers define a key aspect of our Universe. If they had different values, the Universe would be a changed place, and life here on Earth would never have arisen.

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