Leonid meteor shower 2008 - This week!

This year's Leonid meteor shower is currently underway, and is due to peak over next weekend. We are passing through the dusty debris trails left behind comet 55P\Tempel-Tuttle when it passed through the space we are now passing through, as we do every year. As the dust particles (meteoroids) from the comet smash into our atmosphere at speeds of 71km/s they create the bright streaks of light we know as meteors.

Recent advances in our ability to predict accurately when the peak of a meteor shower will occur mean that we can reliably forecast when this years Leonids will peak, although the amount of activity at peak is much harder to calculate reliably. We are getting better though, and estimated rates are usually fairly close to predictions.

This year, the Leonids are predicted to be be in "outburst" mode, which means we are expecting a better than average year. A strong outburst (ZHR up to 150) is expected at 0:22 UT on the 17th November according to predictions by Mikhail Maslov.

Here is a graph of the predicted peak:

See the link above if it does not display properly.

The peak can only be seen from Eurasia, but it's likely that even those who will not see the peak itself will see at least some enhanced activity if observing either side of the peak compared to average years, so don't give up on this year's show if you are not in the right place to see the peak - the shower could still be a very memorable one!

The brightness of Leonid meteors this year is also expected to be higher than average, which is good since the moon will be above the horizon and will no doubt wash out the fainter meteors, but at least it shouldn't spoil the show this year, although it makes things tougher for those of us trying to photograph them!

Leonid meteors are renowned for their brightness, vivid colors, long lived persistent trains, and because the material they are made from is particularly fragile (similar to the consistency of cigarette ash) they often self destruct with a bright flash of light, easily capable of casting shadows on a dark night.

Leonids are also at the fast end of the meteor spectrum. Evey shower has a characteristic speed, and meteors from within our solar system don't come much faster. Be aware that the Leonids are not the only shower active at the moment - this is a very busy time of year for meteors, and there are a number of showers active during this period. Keep an eye out for the much slower Taurids that have been unusually active this year.

Observing the Leonids
The best way to observe any meteor shower, is lying flat on your back, and looking more or less straight up. It's cold this time of year for may of us, so put on a few layers of cloths and climb into a sleeping bag if you have one.

I like to use a sun lounger (look for the ones that go flat - not all do!), which is comfortable (no having to crane neck) , keeps me off the cold ground, and raises me up a bit so that I have a slightly wider veiw of the sky. You want the widest, least obstructed view you can get, and you should try to keep any stray light (artificial or moon light) out of your eyes as much as possible - easier said than done this year!

Timing
The nights either side of the peak night can be pretty good too, so don't be afraid to look for Leonids then, especially if the peak is looking like it will be clouded out.

Although Leonid rates are highest just before dawn when the constellation Leo is high in the sky, I'd also recommend looking for Leonids a few hours after it starts to get dark on Sunday night. Where ever you are this will be at around 9PM local time. Those living further north than 50 degrees Latitude need to head out earlier the further north you are, and those South of 50 degrees can head out a bit later to catch the start.

At this time, Leo is just rising in the East, and although they will be less frequent, meteors seen at this time can be very spectacular and long. Leonid "Earth grazers" as they are known, can only be seen early on when the Leonid "radiant" (the technical term for the part of sky in the constellation Leo where meteors appear to radiate or fly away from) is on or near the horizon. If you only see one or two Earth grazers, chances are they will more than make up for your effort!

As the night progresses, and the Leonid radiant climbs higher in the sky, the meteors will appear to get shorter due to perspective (they are actually coming towards you!), but they also become more numerous, and continue to increase in numbers up till it starts to get light and meteors can no longer be seen against the bright morning sky.

Of course, on the peak night, if you are observing from the right place, the time of the peak will "superimpose" over the changing activity rate that is caused by the position of the radiant in the sky - ie the peak rate that you will experience, depends how high the radiant is in the sky where you are. Location and timing are both important if you want to see the best rates!

Whatever time you decide to try and observe them, be patient - sometimes you have to wait for a while before you see something special. Meteors often come in waves, with lulls of activity in between. Changes of activity from one hour to the next can be dramatic, and predictions can also be off by some margin - fortune favors the patient!

Good luck, and long trains!


Related Links :

Leonid shower info, history, and observations:
meteorshowersonline.com...

Basic visual meteor shower observation techniques:
rtpnet.org...
/2qxmkj

Advanced visual meteor shower observation techniques:
www.imo.net...

Photographing meteors:
www.abovetopsecret.com...

General information:
www.space.com...

Organizations and mailing lists:
www.imo.net...
www.amsmeteors.org...
tech.groups.yahoo.com...

Related threads:
Seen a swift/very swift moving light (colored or white) in the sky? - *PLEASE READ this first*
Heads up - it's a Taurid Swarm year!

Here's a shot I managed to get of a rare all-green Leonid earth grazer a few years back when the Leonids were still in "storm mode". It was taken with a wide angle lens so the meteor has been compressed somewhat - in real life, it seemed to cross 1/3 or maybe more of the entire sky - photographs of meteors really if ever do them justice!


[edit on 9-11-2008 by C.H.U.D.]

Thanks for this info C.H.U.D.
I normally miss these things and find out when its all over, although last year i took my bivvy and a sleeping bag and slept under the stars in north Wales on some sand dunes.
The skies where i live are to light polluted for a decent view.

cheers
jon

quick question- will everyone be able to see it or does it matter where you live. im from new york so what would be the best time for me to see it. otherwise this is really cool i have only once before seen a meteor shower.

Can you see it in the UK? I think. But I hope it's not cloudy on that night , it's always cloudy these days dammit!

reply to post by jon1


You're welcome jon,

I have the same problem here! I'm in the suburbs, and I also try to get away for the main shower peaks of the year.

Since you are in Wales, it might be worth trying to get above the cloud, if you can. I'm not sure how feasible that is, but if you do manage to, the view should be allot better - less atmosphere to look through, and the artificial light pollution should stay beneath the clouds.


reply to post by N. Tesla


No, not everyone will see the peak. Half the world will be in daylight at the time.

In New York, the peak will be at 7:22PM local time on the 16th, and although it's dark then, the radiant is still a bit too far below the horizon to see any activity from it. (I need to correct that in my original post!)

Having said that, if you go out a couple of hours later, you might catch the tail end of the peak as "Earth grazers" - not ideal timing, but never the less you should see some, and they are likely to be of high quality. The rest of the night should still be very good too.


reply to post by _Phoenix_


Yes! Europe, and the UK are well placed for the peak. The time of the peak 0:22 UT on the 17th (Monday morning) is the same as GMT (UT=GMT).

You'll have to head out 1-2 hrs after dark (aim to be observing by 9PM) to catch the start of the show (Earth grazers) on Sunday night, and the display will continue right the way through till Dawn. The same applies for people elsewhere in Europe - aim to be outside after 9PM local time to catch Earth grazers. Those living further north than 50 degrees Latitude need to head out earlier the further north you are, and those South of 50 degrees can head out a bit later to catch the start.

The cloud is a real problem here in the UK and northern Europe, so try to keep the nights either side of the peak night open so as you at least get to see a few Leonids if it's clear.

Even if you don't see the Leonids at peak, they can still leave you dazzled, and don't worry - Europe, Asia, and Africa will get a second shot at a Leonid outburst next year, this time with no moon to dampen the fun!

Originally posted by C.H.U.D.
We are passing through the dusty debris trails left behind comet 55P\Tempel-Tuttle when it passed through the space we are now passing through, as we do every year.

I didn't realize this was related to one specific comet:

cometography.com...

During the 1865/1866 apparition, the comet was only seen until 1866 February 9. Fortunately, enough observations were provided to allow astronomers to determine that the comet was traveling in an elliptical orbit with a period of about 33 years. Nevertheless, the comet was not seen during its expected returns in 1899 and 1932. It was finally recovered in 1965 thanks to a painstaking examination of the orbit by Joachim Schubart (Astronomisches Rechen-Institut).

The last time 55P Tempel-Tuttle comet was seen was in 1998. Based on the above info, we should see it again around 2030 or so.

I will be watching-out, due to you CHUD, thanks!

Edit: Spelling.


[edit on 9-11-2008 by Buck Division]

reply to post by C.H.U.D.



Thanks for this very interesting piece of info. I knew that we have these things every year but i usually miss out on them. But you can count on me lying flat on my back allnight long coming 17th.
Also thanks for the tip on wearing warm clothes and a sleeping bag, that is also something i would have probably forgotten.

PS : flagged it and put it to my favorites

[edit on 9/11/2008 by operation mindcrime]

What the h**l, even put in a star for you....

[edit on 9/11/2008 by operation mindcrime]

reply to post by Buck Division


My pleasure Buck Division,

What you just realized, was the very same thing that led scientists to start looking into meteors and the reason why we know of the existence of more than 30 showers that are active at some time in the year at present. The great Leonid storm of 1833 is the event that set the wheels in motion.

Basically every meteor shower has it's own parent comet, which is why we get distinct peaks in activity, and why we can categorize and classify meteors just as we do with species of flora and fauna. Meteors are like "chips off the old block", and the information carried along with them in their compositions and orbits can be used to study the comet they came from. It also helps when you are trying to count them!

In fact, if you look at the sources of various meteor showers throughout the year, you'll notice that in many cases the same comet is responsible for two meteor showers at different times during the year since there are intersections (or "nodal crossings") between the comet's orbit and Earth's orbit in two places. For example, The Beta Taurids (thought to have been responsible for Tunguska by some) which occur in daylight during June-July:

Strong evidence seems to exist indicating the Beta Taurids are the same stream, or at least closely related to the stream, that later produces the Taurids during October and November. The suggestion was first made in 1951, by Mary Almond and has since been supported on numerous occasions by Nilsson, Sekanina and others. In 1964, Nilsson noted that the correlation of radiant position and geocentric velocity with time was also present during the duration of the Taurids. Other researchers have pointed fingers at the stream's long duration, flat maximum and diffuse radiant as other characteristics previously noted in the Taurids. The Taurids are believed to be a very old remnant of periodic comet Encke---the current record holder for having the shortest period.

sorce

Here's a short animation of how how a dust trail created by 55P\Tempel-Tuttle (in this case dust ejected during the year 1767) crosses Earth's orbit - only in one place in this case, but it serves to illustrate how another comet could intersect the orbit of Earth twice. It also shows how that particular dust trial has evolved, and continues to evolve into the future (up to 2010). The outer red ring represents Jupiter's orbit, and the inner ring Earth's.

www.sendspace.com...

I've also found something similar here if you don't want to download the simulation:
www.digitalradiance.com...

I'll also be eagerly awaiting for the return of 55P\Tempel-Tuttle around 2030 - there is predicted to be enhanced activity (2029 especially IIRC) then due to fresh dust being ejected.

[edit on 9-11-2008 by C.H.U.D.]

reply to post by operation mindcrime


You're welcome operation mindcrime,

As a general rule for observing meteor showers at more northerly latitudes during the colder months of the year, it's better to put more cloths on before hand and take some off later if you are too warm (unlikely IME), than to realize you did not put enough on and spend the night shivering! It's not uncommon for the exterior of my sleeping bag to be glistening with ice crystals by the time it's staring to get light after a long night of observing Leonids!

Don't forget a warm hat and gloves too if you plan on keeping your hands outside the sleeping bag for any length of time! Something to munch on and to drink will also help keep you awake and alert.

can this be viewed from california? if so at what time would be best and date

I live just north of Sydney in Australia. I have a telescope and there is very little city light...I live on an escarpemnt that overlooks suburbia.

Can this amazing event been viewed in the southern hemisphere?

take care
res

Originally posted by ReptileInRays
can this be viewed from california? if so at what time would be best and date

California, and the rest of the continent will be too far West to catch the peak itself - your best bet to see something is to go out a couple of hours after it's dark on Sunday. Try to watch the night before too - it's hard to pick which night will be better for you.

Originally posted by resistancia
I live just north of Sydney in Australia. I have a telescope and there is very little city light...I live on an escarpemnt that overlooks suburbia.

Can this amazing event been viewed in the southern hemisphere?

Unfortunately, Australia will miss out on this peak too. However, and this goes for everyone else who will miss the peak due to daylight, try to watch the night's either side - so Sunday and Monday night. As above, which night will be better is impossible to tell, so try for both to hedge your bets.

Since you're in the Southern hemisphere, the show starts a little bit later - midnight local time is when you want to be out and watching by for the earth grazers.

One thing you won't need is a telescope. You want the widest possible field of view, or you'll miss meteors. By all means bring it with you - you could use it to look at any persistent trains left by bright meteors, but be warned, meteors have a habit of appearing just when you take your eyes off the sky!

If you can get away from the suburbs and light pollution, you'll see more meteors... It's worth doing if you can, but even if you can't, many of the Leonids should be more than bright enough to see where you are.


A general note to all reading this:
When meteor forecasts are made, only specific dust trails are used in the models - there's always a chance that one or more of the dust trails that have not been modeled could produce a surprise enhancement/outburst either side of the predicted peak.

Well Ive just looked at the "predicted" forecast of where I am in the UK (SE) for next Sunday/ Monday..... Rainy and cloudy...

Blast!!! There goes my hopes and dreams down the drain.


[edit on 10/11/2008 by Kliskey]

reply to post by Kliskey


Not so fast Kliskey!

Long range weather forecasts can be extremely unreliable - don't write it off just yet.

Keep an eye on the forecast as we get closer to the weekend. Obviously, 100% clear sky is preffered, but even a few gaps in the cloud for a couple of hrs at the right time can be good. Sometimes, it can clear up at the last minute!

Check this page in the run up, to get an idea where there will be clear sky:
www.metoffice.gov.uk...

As a last resort, jump in the car and drive to an area that looks like it'll be clear - there's usually some part of the UK that's free of cloud.

Try and get out of the SE and away from light pollution if you can too

The IMO has made available "Live ZHR" graphs so we can monitor the buildup to the peak. The graph can be found here:
www.imo.net...

The rate already seems unusually high compared to previous years - and I just confirmed that by checking!

I recommend watching any time when it's clear between now and this time next week wherever you are - and just generally keep your eyes peeled if its clear and late enough for grazers

On a related note, the IMO have also given us Live ZHR graphs for the Taurids which are still going strong as we speak - in fact the Northern branch of the Taurids looks like it has just, or is just about to peak.

All the graphs can be found here:
www.imo.net...




[edit on 10-11-2008 by C.H.U.D.]

thanks C.H.U.D for the reply and other advice.

Sorry about one liner


take care all
res

reply to post by N. Tesla


I lived in Long Island Ny for many years and the best place down there to view them is jones beach out around field 5

Happy viewing

For those of you that have cloudy skies during the shower.

Don't despair!

You can listen to them as they enter our atmosphere....LIVE!
Click here to hear live meteors on radar

The fine folks at the Marshall space flight center in Huntsville, AL have put a reciver
on the web.
Read all about the radios used from Marshall Space Flight Center


As you listen, you will hear strange pings and eerie tones, these are the meteors ionizing
and reflecting signals.

Meteors from different showers, will sound differently, some very fast...some with a long ringing tone.

Give them a listen...It's free!

Enjoy!

I am listening to it now as I type this and I'm hearing at least 3 pings per minute.
The rate will increase from about 0800 to 1200 UTC and more closer to the peak dates.

Thanks for posting that Zeptepi

I always neglect to mention that you can listen to meteors!

Hopefully we'll get to see some too... I'll probably be watching tonight, since the peak is looking very hit and miss weather wise.

Good luck, and clear skies to all

reply to post by C.H.U.D.


Thanks for the reminder C.H.U.D., and for the excellent information you provided here. That was a very informative read. I hope I get some good viewing in this year! (How does a Cannibalistic Humanoid Underground Dweller know so much about celestial phenomena, though?) Cheers!