A few days ago, the web was abuzz with something that looked like a very large meteor burning up over Peru. Here’s video from ITN news:

You can find similar videos on Youtube. However, is it actually a meteor?

Cutting to the chase, I don’t think so. I don’t have a lot of solid evidence either way, but all signs point that way. Here are my thoughts:

1) Meteors tend to move more quickly. They usually burn up around 100 km (60 miles) up, roughly, and are moving at a minimum of 11 km/sec (7 miles/sec) — Earth’s gravity pulls them in to at least this speed. If you’ve ever seen a meteor you know they zip across the sky in at most a few seconds.

2) The two trains (the technical term for what most people would call the tail or trail) are very odd — you can see them in the frame grab here. I’ve never seen a meteoroid (the actual solid bit moving through our atmosphere) produce more than one train. I don’t think this is an optical effect due to the camera but actually two distinct trains.

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Randy Halverson is a photographer who makes incredibly stunning time lapse videos of the sky. And he’s done it again: "Tempest Milky Way", an aptly-named video showing the serene depths of the night sky as a background for furious activity much closer to home:

[Make sure it's set to HD, and make it full screen. You're welcome.]

Holy wow! It’s beautiful enough just showing the stars, but then at 2:20 things really get interesting as storms blow in. There’s lots to see, but keep your eyes open at 1:57 for the silhouette of a whitetail deer on the horizon, and at 3:24 for a meteor that pops into view… and is reflected in the lake!

It’s a breath-taking shot, isn’t it? And it’s a testament to Halverson’s talent, which you can see more of at his website DakotaLapse. I love how the motion of the camera (especially moving up through the corn field) adds a magical sensation to the video. And while time lapse photography like this shows us a dimension we can’t see easily with our own eyes, it’s real nonetheless. Never forget that: the Universe is beautiful, spectacular, and marvelous. Our job is to appreciate it, and try to understand it better.

Credit: Randy Halverson, used by permission.

Astronaut Ron Garan, currently on board the International Space Station, was taking pictures of our home world out the window — and how cool is it to be able to say that? — when he took this amazing picture of a meteor burning up in our atmosphere:

Wow! [Click to bolidenate.] How cool would it be to look down to see a falling star?

He took this shot (according to the header info in the picture) on August 13 at 7:17 p.m. UT, when the ISS was above the Mongolia/China border. This was during the annual Perseid meteor shower, but that doesn’t guarantee this meteor Ron saw was a Perseid. It probably was, though. For an observer on Earth, the Perseids rain down at a rate of about 60 per hour or so. You can usually see about 5 meteors per hour that are just random bits of cosmic detritus. So only 1 meteor in 12 is not a real Perseid, making it likely this one was.

But that got me thinking… [WARNING: math ahead. Cool, tasty, refreshing math that will lead to insight, wonder, potential party conversation (assuming you go to the same dorky parties I do), and other nifty things.]

Meteors burn up roughly 100 kilometers (60 miles) above the Earth’s surface. To make the math simpler, let’s say they burn up at exactly that height, so that any meteor coming in hits this barrier and evaporates. You can picture it as a thin shell of air surrounding the Earth 100 km high, like a force field, or better yet as an umbrella that rain hits (it’s a meteor shower, after all, ha!) and stops cold.

When you look straight up, that barrier is 100 km directly above your head. When you look to the horizon, that distance is actually a little over 1000 km away, because the atmosphere follows the curve of the Earth (you can get an idea of this in the diagram above). The top of this umbrella is then 100 km up and over 1000 km to the sides.

From the space station, though, looking down from orbit at a height of roughly 350 km, more of the atmosphere can be seen because the station is higher up (just like you can see farther if you go to the top of a building). (more…)

I love me some comets.

I’ve seen quite a few in my time. Some were faint smudges in a big telescope’s eyepiece, some seen only in distant spacecraft images, and some so bright they were obvious and awesome to my naked eye.

They used to be considered harbingers, omens up for interpretation by mystics and people looking for reasons things happened the way they do. In reality, comets are just a class of objects in our solar system along with planets, asteroids, dust, and one biggish star.

Hmm. Did I say "just"? That’s unfair. They are gorgeous, interesting objects, worthy of study. And 100 years ago today — April 20, 1910 — we got a pretty good look at the most famous of them all, Comet Halley, as it passed the Earth at a distance of just 23 million km (14 million miles). It got so bright that it was obvious even when seen from cities. As geometry would have it, the Earth even passed through the comet’s tail, sparking fears of widespread death (cyanogen was detected in the comet, making people think it would poison them). It was the talk of the planet, featured in magazines and papers across the globe. For your history enjoyment, here is one of those articles from the 1910, transcribed by James Brooks. It gives a great flavor of the times.

To celebrate this remarkable centennial anniversary, I have put together Ten Things You Don’t Know About Comets. I imagine some readers will know some of these, and some will know all ten, but if you do you can still enjoy the pretty pictures — and make sure you click on them to embiggen ‘em. And if you like this, I have several others, too (Ten Things You Don’t Know About… the Earth, Black Holes, Hubble, the Sun, Pluto, and the Milky Way), so check ‘em all out and see how many things you don’t know.

Apparently, the first meteorite from the fireball over Wisconsin has been found: a pair of brothers discovered a small chunk of the bright meteor that burned up over the midwest skies Wednesday night.

It certainly looks like a meteorite (click to embiggen); the outer blackened fusion crust is from passing through the air, and the interior has the gray, grainy structure in common chondrites. The cube is one centimeter in size and is used in photos like this to give scale.

Pretty cool. There may be thousands of such meteorites lying on the ground in Wisconsin right now; the meteoroid itself was probably a meter or so in size and weighted about a ton. Meteorite hunters are already there searching, and I hope that most of the fallen rocks will be sent to researchers for analysis.

Falls like this are very important scientifically. Having a lot of eyewitnesses means the path and therefore the orbit of the rock can be ascertained, and many times such meteoroids are part of a family of such objects; all on related orbits and probably from the same parent body. When we get samples of the meteorites that means we have samples of an asteroid!

So if you live in that area and find something suspicious, take photographs of it where it is, then carefully put it in a baggie or box (use gloves if you can so you minimize contamination) and contact a local University. The vast majority of rocks found this way aren’t meteorites (we call ‘em meteorwrongs, haha) but it’s worth making sure.

Image: Terry Boudreaux, submitted to Rocks From Space by Michael Farmer.

Just a quick followup on the fireball seen over Colorado and Utah last week: more video is being dug up, including ths phenomenal one from a dash-mounted police car camera:

Wow! I wonder what people not familiar with the night sky thought of this?

Tip o’ the Whipple Shield to The Grand Junction Sentinel.

[For those complaining about my title, I said "midwest" because the meteor was seen as far east as Colorado, which sits on the west/midwest border, and, duh, I needed a word that started with "M".]

By now you’ve probably heard of the extremely bright fireball over Utah last Wednesday, proving once again that really cool stuff happens when I’m on travel and can’t write about it. Worse, it was seen from Denver, which means I might’ve had a shot at seeing it myself.

Sigh.

Anyway, this meteor was so bright it overexposed security cameras, turned night into day, and cast obvious shadows on the ground. This video shows several different views of it:

Whoa.

The coolest thing about these videos is, to me, the way the shadows of objects move rapidly around as the meteor flashes across the sky. I describe this very thing in the opening vignette of the asteroid impact chapter of my book Death from the Skies! The video is pretty much exactly as I imagined it would be. Yikes.

Of course, not everyone thinks this was just a chunk of rock burning up harmlessly in our atmosphere. Because, after all, why assume it was a natural event that occurs quite often, when you can add layers of nonsense and conspiracy to it? Fark alerted me to the idea that this was actually a nuclear missile shot down over the US, despite the video, pictures, and eyewitness accounts completely contradicting the idea that this was anything other than a meteor. But for some people, facts won’t get in the way of a good story!

Anyway, while spectacular, the Earth is probably subjected to meteors like this several times a year. As I have said before, now that we have security cameras and phones with video, we’ll be seeing more and more of videos like this, which is a good thing: it’ll make people more aware of the sky. I’m all for that!