If you’ve ever wanted see what it would look like to orbit the asteroid Vesta in 3D, now’s your chance. You have to have red/green glasses, but I bet after seeing all the anaglyph posts I’ve made, a lot of you do. Anyway, this animation was made by NASA/JPL using data from the space probe Dawn when it was orbiting Vesta at a height of about 2700 km (1700 miles):

Very cool. I was struck the most by how the gigantic mound in the center of the south pole basin has actual and substantially-sized craters in it from impacts! Airless bodies have craters all over them — unless they resurface themselves, like Io’s volcanoes do or they have undersurface oceans like Enceladus and Europa — so it’s natural to see craters on a mountain. But usually mountains are relatively small, so big craters would wipe them out. But that mound on Vesta is huge — it rises 23 km (14 miles) above the basin floor! So there’s easily room on it for big craters.

Vesta’s a weird place, and I’m glad we’re studying it so closely. Even more closely than before in fact, since a couple of months ago Dawn dropped to only 750 km from the surface. The images it’s returning now are really amazing… as you can see for yourself!

Image and video credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

I am extremely honored and pleased to announce that my talk, "An asteroid impact can ruin your whole day", is now featured on the TED website!

I gave this talk in September at TEDxBoulder, and I had a fantastic time. The talks were great, and it was wonderful to be a part of that.

However, I made two errors in this talk. One was logistical; I forgot to say that the "dinosaur space program" line is from science fiction writer Larry Niven, and for that I apologize to him — I usually do credit him, so I’m not sure what happened there.

The second error?
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I’ll be giving my "Death from the Skies!" twice in Texas next week:

1) First, I’ll be speaking at Rice University in Houston on November 14th at 4:00 p.m. in Herzstein Hall’s amphitheater, then

2) I’ll be at the University of Texas – Pan American on November 15th for a 7:00 p.m. talk at the Student Union Theater. The UTPA event requires registration, so sign up! [Update: another page about the UTPA talk is here.]

The talk is about asteroid and comet impacts, and how one could ruin your whole day. I know there are BABloggees in Texas — you guys come out of the wordwork when I write about The Lone Star State — so come on by!

[Yeehaw!]

The eyes of many astronomers — and the eyes of their telescopes — were aimed at the asteroid 2005 YU55 a few days ago, when it passed the Earth at the relatively close distance of about 320,000 km. One of those eyes was actually in space as well: NASA’s Swift satellite. This spacecraft was designed to look at the sky in the ultraviolet, X-ray, and gamma rays, all high-energy forms of light emitted by the most violent events in the universe: exploding stars and gamma-ray bursts.

But the Sun emits UV, and rock can reflect this light, too. So Swift observed YU55 as it passed us, and got this very interesting footage of it, what I think is the coolest I’ve seen so far:

[You can also watch it on YouTube if you prefer.]

Pretty neat, and by looking at the rock at different wavelengths, we can learn about its structure and composition, too.

But I know what you’re thinking: in the video, why did YU55 curve around as it moved? As it turns out, I was expecting this when I watched the video! What’s going on^*?

The asteroid is in elliptical orbit around the Sun, but over the short period of time covered by this video — about 20 minutes — it’s essentially moving in a straight line. The reason the path is all bendy is because Swift itself is in motion! Swift orbits the Earth, circling us once every 90 minutes or so. As it moves around us, its viewpoint is changing, and that motion is reflected in the asteroid.
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Tomorrow, November 8, the 400-meter-wide asteroid 2005 YU55 will glide past the Earth, missing us by a very comfortable margin of 320,000 kilometers (200,000 miles). This distance is three-quarters of the way to the Moon, and is in fact so far that you’ll need a decent telescope to see it at all.

However, I’m starting to see rumors that the asteroid will have an effect on us. I expected this — it happens every time there’s a decent-sized rock that whizzes past us. That’s why I wrote a post about it a few months back, but I want to follow up on it. Why? I’m getting wind of some folks worried about YU55, including a couple of notes on Twitter saying there are people blaming Saturday’s earthquake in Oklahoma on YU55!

Let me be clear: no asteroid, YU55 or otherwise, can cause earthquakes as they pass. Even Ceres, the largest asteroid in the solar system, would have to practically skim the top of our atmosphere to have any real effect on us. YU55 is dinky, and will miss us by 25 times the diameter of the Earth!

And c’mon: why would it shake up Oklahoma? Japan, Turkey, Chile, California — there are dozens of seismically active spots on Earth that are more prone to earthquakes. Someone claiming an asteroid causing one in Oklahoma should set off alarm bells in your head^*.

I’m sure there will be other claims as well. People will squeeze whatever they can out of this event. I saw it happen in 2008 when a similarly-sized rock, 2007 TU24, passed by us at a distance of more than half a million kilometers. Things got so ridiculous with the doomsday scaremongering back then that I made a video to alleviate fears. I’ve embedded it here; all you need to do is replace "2007 TU24" with "2005 YU55", and the 530,000 km miss by 320,000 kilometers, and all the stuff I said back then still applies.

And for those of you still prone to worry, let me add this: I was right. And when was the last time an end-of-the-world doom crier was right?

Let me give you a hint: Never.

Not that this will stop them. There’re two things I know for sure: they’ll never admit they were wrong, and there will always be something else. The next asteroid, the next full Moon, the next star they think will explode, a pole shift, whatever.

As long as people aren’t familiar with the reality of the situation, there will be fearmongers to take advantage of the situation. That’s a big reason I do what I do, and why I have to do what I do.

Image credit: NASA/Cornell/Arecibo

^* You’d think at least they’d claim it was last week’s solar flare that did it; after all, it’s Oklahoma, where the solar wind comes sweepin’ down the plain…

On November 8, an asteroid 400 meters across will pass by the Earth, missing us by the very comfortable margin of about 320,000 kilometers (200,000 miles). Named 2005 YU55, it’s been known for some time that this pass will occur, and astronomers are jumping on the chance to observe it.

First off, it’s no danger to Earth right now. It’s what’s called a Potentially Hazardous Asteroid because its orbit intersects ours, but observations have shown it won’t be a danger to Earth for at least a century, and probably much more. There’s been some scare-mongering about it over the past few months, but as usual that’s all baloney. This rock will pass us safely, sailing on into the night.

But given that this is close in astronomical terms, astronomers will be observing it carefully. There are plans to use NASA’s Deep Space Network of radio telescopes, as well as the Arecibo ‘scope in Puerto Rico (which was used to make the image above back in April 2010). They’ll be able to see features on this rock as small as two meters across, which means we’ll actually get some interesting images of it, I hope. I’ll post those as soon as I see ‘em (which will be after November 8).

It’ll only get to a magnitude of about 11 — only 1/100th as bright as the faintest star you can see with your unaided eye — so you’ll need a decent-sized (12.5 cm at least) telescope to see it. 320,000 km is 3/4 of the way to the Moon, and this asteroid is small and very dark. Observing it will be tough, but you can get more info on how to do it at the Minor Planet site and on The Minor Planet Bulletin (PDF).

When I was a kid, asteroids were not much more than mysterious points of light, but now we have the technology to see them in detail from the ground, and even send space probes to get good, close looks at them! And, of course, the technology to spread those images and information as quickly as the speed of light around the globe. Sometimes that’s used to spread misinformation, but it also can be used to show people what a cool place we live in. I prefer the latter.

In September 2011, I was honored to be on the speaker roster for TEDxBoulder, which is a local though independently-run version of the much-lauded TED talks. My talk was about saving the Earth from asteroid impacts, something I’ve spent a lot of time thinking and writing about.

The talk is online, and I’ve included it here:

The "We have a space program" line is from science fiction author Larry Niven, so I can’t take credit for it, though I modified it to add the "we can vote" bit. Also, this was the biggest audience I’ve ever spoken to, and it was a great crowd. I was almost last on the roster, but the audience was attentive and clearly enjoying themselves. It was a really fun, energizing, and mind-expanding evening.

The other talks that night are being put online as well. If you ever get a chance to attend a local TEDx conference, you should.