The best of the Perseids

6 09 2010

I’ve seen a lot of pictures of meteor showers over the years, but this guy has some real winners.  Like this one…

His name is Pierre Martin, and I’ve been following his ubiquitous meteor observing reports for years.  …including *this* year in which I saw way fewer Persieds than normal while he saw >100/hr at one point.  Quite an amazing guy in my book.  Of course, he IS from Canada, so we’ll have to take into account the conversion rate.  Click the picture to check out the rest of his flickr photoblog.  [you want to do this!]

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Planetary grouping for the Perseids

10 08 2010

You can see by this image I stole from Sky & Telescope that we’re due for a really cool planetary grouping in the west over the next few days.  It’ll be a real challenge to pull Mercury out of the glare of the setting sun (if not impossible without binoculars), but see if you can spot the other three planets this week.  They’ll be approaching the horizon around 9:30, so you’ll have to look before then.

And be sure to catch Jupiter rising in the east around 10pm.  It’s the brightest thing in the sky from that time until dawn this week, so you can’t miss it!

After 10pm you can start looking for Perseids.  The peak is Thursday night/Friday morning, but you can catch elevated rates of meteors all week.  Perseids tend to be quite fast, and the brighter ones look yellow to me.  About a third of them will leave persistent trains, which can leave an indelible memory for any witness.  Remember, even though they can light up the sky and leave a brilliant streak across the heavens, they’re rarely larger than your fingernail.  And Perseids almost never make it to the ground.  Each one will burn up at least 25 miles over your head.  Amazing, huh?

Let me know if you see something spectacular!

Boring title.  Awesome topic!https://infinitewell.files.wordpress.com/2010/08/st-8-12-10.jpg?w=500





Perseids 2010!

6 08 2010

The spectacular Perseids meteor shower is almost upon us!  This year the best rates for the American continent will occur on the morning of Friday, August 13.

Remember last year? I told you all about the really good rates, but even I didn’t go out for more than a casual look.  Most likely, neither did you.  We had a glaringly bright full moon that just made observing near impossible!  This year the rates are still high; and — good news, everyone! — there’s no moon to worry about.

The meteors within this shower were shed from comet Swift-Tuttle, which passes across Earth’s orbit every 135 years.  The last time it was here was 1993 when observers in Europe saw 200-500 meteors/hour!  We won’t get nearly that number this year, but the rates will still be substantial.  And with the peak occurring just two days after new moon, the only thing keeping you from seeing a smattering of your own Perseids will be the weather.

The Perseids will be falling all night with an expected rate of 60 meteors/hour.  Remember that as with most meteor showers, you will sometimes go for 5-10 min. without seeing a thing, then four or five will zip across the sky all at once!  As the evening turns toward deepest night, the rates will increase dramatically; and near dawn you can expect almost 120 meteors/hour.  Remember that the farther north you are, the higher the radiant will climb and the more you’ll be able to see.  But also the farther north you are, the sooner night turns into day.  So those living around 30 – 35 degrees north latitude (MY latitude!) probably get the best overall show.

So set aside some time Thursday night to relax outside with a reclining lawn chair and some bug repellent.  You don’t want another year getting by without watching this ancient event.  It’s really special.

Most folks, like yourself, only want to lay back and see how many they can count.  What a serious observer like me would do is take good notes and file a detailed report with one of the major meteor organizations.  (how nerdy am I?)  But there *is* a group in Britain trying to get the public to help them gather data by using Twitter.  I have a bit of a problem with this as I would prefer people to not take their eyes off the sky long enough to punch characters on their phones.  Also, unless your phone has a deep-red-only display, you’ll kill your night vision the moment you look at the screen.  But… maybe it’s a worthwhile effort.  And if we can get a bunch of people actually interested in looking beyond just the pretty and trying to contribute some real science — well, who am I to complain?

Here’s their warm-up video.  It’s a little on the “sensational” side, but awesomely entertaining!

[You gotta watch it fullscreen!]





A Leonid To Remember

7 12 2009

Yes!  I just got permission from the owner, Mikiya Sato, to post this incredible image he took of a Leonid here on my blog for you, my awesome readers.

Okay, now click on it to see it in better resolution.

I know, right!?!?  Wow!

But that’s not all…  if you click here, you’ll see a gorgeous flash sequence of the event plus images of the expanding vapor cloud over the following 10 minutes.

Viewing this makes me excited enough to set up my laptop and digital camera to capture meteor images myself, just to see if I can.  Unfortunately, right now there’s a construction project going on east of my house which is going to completely wash out the eastern horizon for the next several months.  But it does give me some ideas for the future.





Big Bang Baby!

19 11 2009

Fireballs.  They happen.  They happen far more often than you think.  Not usually over people, though.  But sometimes…

This picture was taken at seven minutes past midnight Tuesday night/Wednesday morning.  The fully illuminated landscape is a result of the ultra bright bolide that resembles the sun with a tail that you can see plummeting toward the ground.  Though it looks like it’s not far away, it’s many dozens of miles up and several hundred miles away from the camera.

Here’s the amazing part:  The corresponding sonic boom actually shook the ground hard enough that it set off seismic sensors in at least three states!  Now that’s a big kaboom!   Since sound travels a lot slower than light — only a mile every 4.8 seconds or so — it took the people in Salt Lake City (where this image was taken) 5 minutes after the sighting to hear it.

A lot of people saw this event, many more than normally would have, because they were outside watching the fantastic Leonid meteor shower.   But before you start putting two and two together, the Leonids did not produce this!  Though this happened during the Leonid peak, it does not appear that this meteor came from the direction of Leo (the whole reason we call this shower the Leonids in the first place).  That means it has another origin.  All we’re really sure of at this point was that it detonated very high up with a power of just under 1 kiloton.

If you go to spaceweather.com, you’ll possibly find some links to some news agencies.  Careful what you believe if you click on any of them.  One of the reports has a guy who has a friend who is studying astronomy and his friend told him that a green meteor means it contains iron and since this one was green that means it had a lot of iron in it so it must have survived all the way to the ground but its probably not very big maybe the size of a cheeseburger or something.  Wow.  All that just from being told the light was green, huh?  Hey, guess what.  They almost all have iron.  That green light is probably caused by the meteorite slamming into our atmosphere’s oxygen.  It glows green too, y’know.  And, of course, there’s a lot more to it than what I just handwaved as an explanation.  Just remember that you can’t really tell anything from a visual observation of the color — you need a spectral analysis to determine composition.  And be careful of the other things that the reporters were quick to leap on.  The probability of interviewing a common Joe with a solid astronomy background is rather slim.

Many annual showers can drop fairly bright fireballs, most notably the Leonids fireball outburst of 1998.  [I saw a dozen bolides brighter than magnitude -8 that night!]  But the Leonids is not a shower that can drop big things.  Most of the meteors you see in this shower are roughly the size of your fingernail.  A bolide this big requires a good sized rock.

The meteorite community is fairly certain that a meteorite was dropped from this event.  And it appears increasingly likely that it’s in western Utah at a place called the Dugway Proving Ground.  One thing *I’ve* gained from following this story is discovering the history of the DPG.  I would wager from the information available to me on the ‘tubes that it might be a while before anyone gets out there to search around for it, if in fact this turns out the be the impact point.  Also, after poking around I remembered that the Genesis probe touched down (and if you know the story you should be laughing) there back in 2004.  It’ll be interesting to see how long it takes for the military to let people look for debris.

There’s also a side story about some shimmering high-altitude clouds over Utah the next morning — six hours later.  It’s difficult to temporally link these two events together, but no one really has a better explanation.  Interesting, huh?

[What’s the difference between a fireball and a bolide?  Here’s a previous post where I address that.]