When the first episode of Bad Universe aired, my Aussie friends complained about us choosing Sydney as the impact site of a small asteroid. We chose it because most other major cities have already been wiped out in TVs and movies, and the Sydney Opera House was so iconic we knew it would make a great visual (it did).

But as much as my friends complained, they had it easy. Check out this impact site just a few thousand kilometers west of Sydney:

[Click to impactenate.]

That’s Shoemaker (formerly Teague) Crater, an old impact crater about 30 km (19 miles) or so across. It’s a bit tough to see, but it’s the oddly wobbly circular shape right in the middle of this photo. Craters this big are hard to see from the ground, and are easier to identify from space; this shot was taken by an astronaut on the International Space Station. Like many large craters, it has multiple rings around it, probably formed as massive shock waves from the gigantic impact slammed through the ground. There’s a ridge at the bottom of the high-res photo that’s part of a heavily eroded outer ring. This crater is in the Outback, with mostly brown rock punctuated by colorful salty lakes.

I knew it was old just by glancing at it. Young craters look young: fresh, sharp rims, obvious outlines, sometimes surrounded by rays (long, straight features pointing away from the center of the crater, formed when plumes of ejected material collapse). This one is sloppy, vague, faded. Estimates of its age vary. It may be as young as 570 million years, or as old as 1.3 billion years! Some estimates put it even farther back along Earth’s timeline. Australia itself is ancient, with some parts having been around for 4 billion years. This crater dates back to the Precambrian age, when the most sophisticated lifeforms on Earth were soft multi-cellular microscopic creatures; the first true fossils of hard-shelled life were still millions of years in the future, even for the younger age range of the crater.

It’s hard to imagine that our lush green and blue Earth was once covered with craters like this. Heck, a few billion years ago this one would’ve been considered small! But two things have changed that: for one, the solar system had a lot more rocks to toss at us back then. Things have thinned out considerably in the past few billion years. Plus, the Earth isn’t static: it’s dynamic, with erosion and continental drift wiping out really old craters. Only a few survive now, the ones that happened to be in very stable locations like this one. Studying them is like having a direct line to the past, though muffled by time and change. Still, it’s an amazing look into what things were like before life took hold on land all those eons ago.

Oh, one more thing: if the name is familiar, it should be. It’s named after Eugene Shoemaker, a geologist who was a pioneer in studying and identifying impact craters like this one. He died in 1997 in a car accident in Australia, so it’s fitting a crater there was named in his memory.

Image credit: NASA

- Raising an impact in Africa
- New study finds giant impacts aren’t periodic
- "Amateur" geologist finds a South American crater
- Deforestation reveals an old scar
- Terra spots an impact on, um, Terra
- Impact
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This makes me so happy: my pal Chris Hardwick — look up "nerd" in the dictionary if you’re not familiar with him — is taking his gargantuanly popular Nerdist podcast to the TV airwavery:

W00t! This airs after Doctor Who on BBC America September 24 here in the States, and I will watch (though on my DVR as I’ll be at TEDxBoulder talking about trying to save the world). I’ll note this will be broadcast so it’ll be PG-13 or so; that ought to be fun. His podcast is NSFW in much the same way that standing next to a gamma ray burst is Not Safe For Being Alive.

Chris is really, really funny and one of the few bigger Doctor Who fans than I am. And I am not at all jealous that his guests on the show will be Matt Smith and Craig Ferguson. Not at all.

[sob]

Starting Friday, my TV show "Bad Universe" will air on Discovery Channel Latinoamérica, which I think covers Central and South America. Check your local listings. The name has been translated to "Mitos Del Universo", which of course means "universal mites"; a clear reference to the second episode "Alien Attack"… which itself was translated to "¡Ataque extraterrestre!" But then, my Spanish isn’t very good.

I hope they got Antonio Banderas to dub my voice, though. That would be muy bonito.

Tip o’ the asteroide to eltiocesar.

I just got word that my three-part science TV show, "Bad Universe", will be airing in Brazil soon! I can’t embed it here, but they have a promo video up at that link.

I had no idea I could speak Portuguese.

Actually, for the dubbing, they did get someone who sounded a lot like me (and used me own voice as well, like when I said "Whoa!"). Anyway, this is cool news, especially since it’ll be airing in the UK very soon too. I don’t know when exactly it’ll air in Brazil, so if you live there keep your eyes on the DiscoveryBrasil site.

Tip o’ the Brazil nut to Carlos Cardoso.

I’ve just learned that all three episodes of my TV show, "Phil Plait’s Bad Universe", will air in the UK on DiscoveryUK from August 15th through the 17th. The air times vary, so check the link to find out when it’s playing.

Sky TV has clips online to give you a taste of the three episodes: Asteroid Apocalypse , Alien Attack, and Death Stars. If you sense a theme, well, read the title of the show again.

Hope you like ‘em!

And by the way, the DVD set is available on the Discovery Channel store and at other online venues like Amazon.

Perhaps you’ve seen the video of George Hrab and me performing his song "Death from the Skies". And perhaps you’ve seen my own show, "Bad Universe".

Now, thanks to Dana Peters, you can see them together:

After all, these are the real ways the world will end.

Nature imitates art! Kinda!

I am endlessly fascinated by impact craters. You might think they all look alike, but they don’t. They have different shapes, structures, shading, even (sometimes) colors. And these features can tell us a lot about the object that caused the impact as well as the structure of the surface they hit.

For example, here’s a nifty crater on the Moon as seen by the Lunar Reconnaissance Orbiter:

That image is 500 meters (.3 miles) across, so this is a decent-sized hole [click it to enlunanate]. Note the rubble; that’s a clear indication that the surface of the Moon where the object hit was rocky as opposed to sandy. You only get fractured boulders like that when the impacted surface has some cohesion. Most of the Moon is covered with a layer of dust called regolith, but here, under that powdery surface, was rock.

I’m not a geologist, so that wasn’t the first thing I thought of when I saw this picture. What I did think of was how familiar this crater looked to me. And it didn’t take me long to figure out why…

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