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New Moon Sets Stage for Brilliant Leonids Meteor Shower
Leonids Meteor Shower as seen from Joshua Tree National Park in 2001. Image Credit: Wally Pacholka / AstroPics.comLeonids Meteor Shower as seen from Joshua Tree National Park in 2001. Image Credit: Wally Pacholka / Bill Cooke was online on Monday, Nov. 16, 2009 at 4:00 p.m. EST and for over 90 minutes fielded numerous questions about this year's Leonids Meteor Shower. Many thanks to everyone who joined us for today's chat.

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(Moderator) Brooke: The chatroom is now open. This is a moderated chat. Please stay on topic! Our topic today is the 2009 Leonids meteor shower. Bill Cooke of the Meteoroid Environment Office at NASA's Marshall Space Flight Center will take your questions.

(Moderator) Brooke: Let's kick things off with a question for Bill. Bill, what will be the best viewing time to see the Leonids this year? And what would a person need to see them?

(Moderator) Bill: Brooke - the best time to view will be tonight, between midnight and dawn. Get a sleeping bag and go away from city lights. Lie flat on your back, look up and enjoy the show!

(Moderator) Brooke: Remember, everyone if you don't see your question right away, it may be in queue. Please allow the queue enough time to catch up so you can see your question/answer.

zeemie: If I live in the mountains of Western North Carolina, will the meteor shower be visible at any point tonight or early evening tomorrow?

Bill: Zeemie - you will see Leonids between midnight and dawn tonight.

Alexb: I live in the Southeast U.S., what is the best time to see the Meteor Shower?

Bill: For anyone in the U.S., the best time to view is between midnight and dawn. You will see more meteors close to dawn. Dress warmly!

bluebobcat: Does debris from meteors ever interfere with satellites?

Bill: Satellites have been hit by meteors before, but the usually only cause a minor problem. Only one satellite has been "killed" by a meteor.

Jenna: Hi Bill! I'm a Canadian living in Europe (Switzerland) and wondering when the Leonids will be best viewed from this region. I've heard mixed responses... some saying early hours of Nov. 17, others saying it will be barely viewable.

Bill: Europe will see roughly the same conditions as the U.S. - look in the wee hours before dawn.

Sky_Watcher_1978: I know that Leonid meteors hit Earth's atmosphere at around 16,000 mph, which from what I've read, is quite fast. How do the Leonid meteor impact speeds compare to the impact speeds of other meteor showers such as the Geminids and Perseids?

Bill: Leonids move at 156,000 miles per hour - they are the fastest of all meteors. Geminids are half the speed of the Leonids, with Perseids between the two.

Jason: Where can I see the showers?

Bill: You can see Leonids from anywhere the skies are clear and there are no city lights.

eome1: Hi, I'm a physiscs student in the UK. Weather permitting I will have the chance to observe the shower from my university's observatory. We have a 12" reflector at out disposal. What wil I expect to see?

Bill: Absolutely! Just go out in the early morning hours, and look up!

kanwalq: Are the meteors only viewable on a super clear night?

Bill: No -- but clear skies are necessary to see fainter ones.

MeteorWayne: Hi Bill, nice to "talk" to you. In researching your prediction, I have not found which trails are involved in the 200-300 ZHR peak. Is it the 1466 and 1533 trails? Thanx, MW

Bill: It is -- the 1466 and 1533 trails will produce the outburst.

Reb:  I'd like to know if any equipment is required or if we could see them with the naked eye, as well.

Bill: No -- just use the naked eye. You want to take in as much sky as possible.

bluebobcat: do any meteorites from Leonids fall to earth?

Bill: No, Leonids burn up about 60 miles up.

twirlgurl:  will it be easier to see with a telescope?

Bill: No, just use your eyes! Telescopes have too limited a field of view.

Kerry: midnight and dawn anywhere, or does it vary with time zone?

Bill: Yes, midnight anywhere.

Ark: How will be the conditions for the viewers from Southern Hemisphere?

Bill: What part of the Southern Hemisphere? South America? Australia? Africa?

Lizzie: i live in europe, are the viewing times the same?

Bill: Yes

nb: Have seen 2012 last friday in theater..In anyway this is precursor for 2012 predictions ?

Bill: No. :)

KIRKULEAZ: Afternoon Bill, just wondering if in a place like where I live (Los Angeles) there will be a decent meteor display tonight?

Bill: If the skies are clear, and you get out of the city.

Rawnnie: Around what time will the showers be visible in southeast asia?

Bill: 2 to 5 a.m. on the morning of the 18th, depending on the location.

SkyZen: I can't get to a dark site away from the city tonight, would it still be worth staying up late for viewing even from the suburbs?

Bill: You'll only see brighter Leonids from a suburb or area of the city. Tough to call!

Jenna:   Bill - is that true of Europe too? I'd heard that it will be difficult to see because of the position of Leo.

Bill: Leo rises about midnight, and you should see Leonids beginning then. Max 25 per hour just before dawn.

Aislinn:  How intense is the shower this year compared to past years?

Bill: 1999, 2001, and 2002 were meteor STORMS when the rates were 2,000-3,000 per hour. So, this year's outburst isn't anywhere near as spectacular.

melliemel: Is there anywhere in the US that you may not be able to see the shower (based on location...not specifically weather)?

Bill: No...location is not a factor.

Lgizzy: how about which direction to scan the sky say from east coast florida?

Bill:  Look straight up and slightly to the east.

SoundGuyNick: Given that this is predicted by some people to be a spectacular meteor shower, do we know of any observatories that are planning to make recordings of the night sky for posterity's sake?

Bill:  We at Marshall, but most observatories do not look at meteors -- they look at galaxies and things like that.

MeteorWayne: OK, another technical question. How does your model differ from those of Maslov, Vuabaillon, Asher, etc?

Bill:  We have fewer particles, so our model doesn't show details of Vaubaillon.

sonallyk88:  hi there! just wondering when would be the best time to check out the shower @ AST

Bill: What is AST?

Anjo: What about the western side of Puerto Rico? Would I be able to see the meteor shower and when?

Bill: Yes, if clear. Same time as rest of the U.S.

J.Bean:  Was the timing of today's shuttle launch planned to coincide with the Leonids Meteor Shower?

Bill:  No, shuttle mission was scheduled well in advance. Timing is driven by timing to service the space station.

Aldraku: and what about europe any chance of seeing any ?

Bill: Absolutely.

Karl: Will I see some meteors in lebanon ?

Bill: Yes, but you won't see the outburst. Too far to the west.

DenverExaminer: What are the best viewing times for my friends in Asia? I would like to offer recommendations to my American friends there.

Bill: Again, between 2-5 a.m. depending on the time zone.

Kerry: will they be easily visible to the naked eye?

Bill: Absolutely. Nice bright streaks of light.

Mrpacman66: I live in Los Angeles. If I go to a nice view overlooking the entire city of LA, what time will be a good time to view the meteors and is this a good place to look out?

Bill: Not familiar with L.A. Griffith Observatory?

gatortwins:  what part of they sky will they appear? If I have to look out of a window, do I look North or South?

Bill: The Leonids appear to come from the Constellation Leo, and this year because of a coincidence, appear to radiate from red planet mars -- which is in Leo.

MeteorNut: Why are they called Leonids?

Bill: Meteor showers are names after constellation the meteors seem to come from. Leonids come from Leo, Geminids from Gemini, Perseids from Perseus, etc.

Sophia:  Hi. My name is Sophia. i am six. Can you see the meteor shower if you were in outer space?

Bill: Hi Sophia. Yes, but you'd have to look down into the Earth's atmosphere. You're seeing meteors from above.

alvaro:   I live in Orlando, Fl... what is the best time to see the meteor shower?

Bill: Between midnight and dawn ANYWHERE in the U.S.

RichPowers: Thanks Bill, you answered my question before I could ask it.

Bill: Good deal. :)

mahalcj: What direction in the sky should we look to get the best chance of seeing the meteors?

Bill: Look up, slightly to the east

Sky_Watcher_1978: Bill - I understand that the forecasted amount of meteors tonight for the United States is between 30 and 60 per hour in perfect viewing situations. Historically, what year did the Leonid meteor shower put on the best show and how many (approx.) occurred?

Bill: Some disagreement. 1833 was the year the "stars fell,” though some researchers claim 1966 saw up to 100,000 meteors per hour.

MeteorNut: Where do the meteor particles come from?

Bill: A comet called Tempel-Tuttle. They are ejected from the comet when it passes close to the sun.

twinprism: Do you have any recommendations for photographing a meteor shower?

Bill: Yes. Set focus at infinity and take long-time exposures set at 1-5 minutes. Hopefully you'll catch a meteor. Some luck is needed. :)

adnan140: Would i be able to see this in London, UK?

Bill: Yes

buckeyetom22: Will what i see be streak like as in a falling star or more of a series of explosions as these bits of "debris" hit our atmosphere

Bill: Streak like a falling star -- up to 25 falling stars per hour.

wishingstar56: How long is the meteor shower? Some websites say that it is for 2 days?

Bill: Yes. Leonids last 2 days, but outburst or most intense part is only about 8 hours.

Pleiades_Sister: A friend in Australia asked if they could view there. Will it be visible from there?

Bill: Yes, but barely. Leo doesn't get very far above the horizon.

Jason: If the comet that makes the Leonids only comes by our solar system every 33 years, just how much meteor debris is left behind that Earth keeps passing through it every few years?

Bill:  Unknown -- but LOTS! :)

egvick:   Bill, tell us some of the things you find most interesting about meteors and meteor showers. Thanks!

Bill:  Meteors are the leftovers from the origins of the solar system. They're billions of years old, older than any Earth rocks. The showers tell us how these particles make their way through the solar system. They're records of past comet activity.

kanwalq: Are meteors visible on a cloudy night?

Bill: Unfortunately, no. Not unless you're on the space station. ;)

MeteorNut: Are there other places on Earth that can see the shower better?

Bill: Yes, in Asia

micky: hi do we know of meteor hitting humankind anywhere . Has it been dangeroues and how about the pollution. I heard that the deberies are rich in resources, does it contain diamonds..?

Bill: Leonids don't contain diamonds. But if you find one, I want to know about it. :) As far as meteors hitting anyone, a lady was struck in Alabama in the 1950s by a meteor that came through the bedroom roof and bruised her side. In Canada, an SUV and a Chevrolet are meteor casualties.

MeteorWayne: On a personal level, do you ever get a chance to sit under the sky and watch a shower, or are you always too busy with instrumental campaigns?

Bill: I'm too old to do much observing. Prefer to stay warm! My computers and cameras do most of the work. I leave observing to the younger generations. I "served my time." :)

Alexb: Would the meteor shower be taken into consideration in regards to the launch of Atlantis?

Bill: Yes.  Shower forecasts were provided, and factored into the decision to launch.

ant: will the meteors be predominantly in one area of the sky (ie: southern horizon) - or will they be all over?

Bill: All over

Mil: Enjoy the metero shower! Bye! (Mil - Future Rocket Scientist/Aeronautical/Aerdynamic/ Aerospace physicist

Bill: Thank you. You, too.

MMM:  Bill, will there be any meteors visible in Southeastern US prior to midnight tonight?

Bill: Very few. Leonids are usually not visible until after Leo rises.

rchristianb:  Since STS-129 just lifted off with success a couple of hours ago do you think they will get to see any part of the show or have any camera equipment to capture the event?

Bill: We have video of meteors recorded by shuttle and station cameras. If astronauts have time to look down, they'll see meteors down below.

rangsiy: I live in Indiana. Will I see ANYTHING at 11pm? Or it's nothing until midnight?

Bill: You'll see a few background meteors, maybe 4-6 an hour. Almost no Leonids.

Aldraku: I'm curious what are those meteors made of ? metal ? or just rock

Bill: Leonids come from comet that's a big, dirty snowball. So Leonids are bits of ice and dust. Some meteors (not Leonids) come from asteroids and are made of rock.

wrumbley: Any particular location in the sky for maximum number of meteors (Detroit area)?

Bill: Look up and slightly to the east

ericm: Can anyone explain to me why the flight path the shuttle takes appears elliptical?

Bill: Please contact JSC's public affairs office.

bartellas: Will it be roughly the same times in Ottawa,Canada?

Bill: Yes

Robert_Eachus: Are any of the predictions on meteors per hour based on viewing the meteors / debris from Comet Tempel-Tuttle that the Earth is about to pass through?

Bill: Maximum rate in Asia is 200-300/hour. Western Hemisphere, 25 or so/hour.

Erin: Is there a scientific program to observe the Leonids, perhaps with spectronomers?

Bill: Yes. We have observed meteor showers striking the moon here at Marshall for a couple of years. Other programs in Canada and Europe also observe. And there are some meteor scientists in Czech Republic that observe meteor spectra.

rick: I know comets are large and a lot of debris is left behind on each trip through our system. But it seems amazing to me that there is enough to produce a shower every year. Is there an estemate as how much debris is left on each pass?

Bill: Hmmm. Estimates, but I can't recall exact numbers. None for Tempel-Tuttle comet that I'm aware of.

apollo13: So if you can see the stars you can see the shower?

Bill: Yes

SkyZen: I'm going to be stuck in the suburbs tonight. Will I still be able to see enough meteors to make it worth watching?

Bill: Only the bright ones. Your call.

eome1: Is there any advantage in observing through a telescope?

Bill: No, eyes are better.

smbspace: you can see anywhere from 10-12 meteors on any given clear night

Bill: More like 5-10, but yes.

Chutzpah: Hi Bill, how many meteors would you think hit the atmosphere, on average, during a shower like this? (I know it will be a bit of a guess!)

Bill: Let's see...figuring'll see on the order of 80 Leonids assuming clear skies, if in U.S. tonight over five hours. Your eye sees about 10,000 square km.

wrumbley: Are there separate showers for each 33 year comet pass, or does the comet follow the same path during each pass?

Bill: Different path, with separate showers for each comet pass.

MeteorWayne: It should be pointed out that using a telescope is not the best way to watch a meteor shower. While useful scientifically, it's far better to sit back and watch as much of the sky as you can.

Bill: Agreed

Wigi:  I am in Alaska... assuming it is clear enough, and that dawn doesn't really get going here until about 1700 UTC, will we start to see an increase in rate from the second peak?

Bill: Yes

Jon: Hi.From your article at,'Look up!It's the Leonid Meteor Shower''the Leonids will appear tobe shooting alomst directly out fromMars,'just coincidence',Are there known instants when other planets graviatational effect cometary debrib &their meteors?

Bill: Coincidence in the case of Mars, but Jupiter and Saturn can alter the path of meteors passing near.

Lennart: Can you see this shower in europe?

Bill: Yes

kbrown: Is there any danger to the Shuttle?

Bill: The risk posed by Leonids to shuttle is small compared to risks posed by background meteors and man-made orbital debris.

melliemel: A shuttle went up today. Did it interact with the shower in anyway?

Bill: Hopefully not. :)

Erin: Is the number of meteors tracked from year to year, and does it have any scientific use?

Bill: We don't track them like we track space junk. Yes, information we gather from periodic observations is of scientific value.

dhara: i stay in eidson nj will i be able to see the shower

Bill: Yes

DEYVID_CHAVES: You can see the meteor rain in Brazil

Bill: Yes

erickristiansen:  I am located in Chicago, in the Northwest suburbs. I heard there may be cloud cover. If I go out to Rockford, Illinois, will I be able to see anything, and if so, what time?

Bill: If skies are clear, yes. Look after midnight.

Jim_Kennedy: tonight, correct?

Bill: Yes

agibson: Shouldn't one be able to see a fair number of meteors even before Leo rises i.e. before midnight?

Bill: sporadic or background meteors, not Leonids

stephen: at what time will the shower be visible in Mexico?

Bill: After midnight and before dawn

jasroy:   What about in the US? I'm in Florida and i want to see the meteor shower

Bill: Great. Look up and slightly to the East after midnight and before dawn

bgrg500:  I live in central usa my kids would love to see this but waiting until midnight probably wont work, any chance will get a decent show earlyer in the evening?

Bill: Unfortunately, no. Leo has to be above horizon

Alexb: Since we cannot see it in the daylight and you mentioned it starts around midnight in the U.S., how long does it actually continue for?

Bill: Leonids shower lasts two days, but outburst in Asia only lasts for 8 hours.

JuliePout: Hi, are the showers visible in south-east England?

Bill: Yes

Gaea: Hello all! I am from Venezuela, and I would like to know if we will see the leonids meteor shower?

Bill: Yes. Look up and slightly to the East after midnight and before dawn

shrew:   will you guys be looking out for ufo activity there has been alot of sightings in the uk over the last two days????

Bill: Don't expect a mother ship appearance. :)

PeytonP: Hello and thanks for the advice. At what degree will Leo be rising tonight?

Bill: After midnight

jay721:  and for north america, the time is midnight to dawn on Nov.17th?

Bill: Yes

smbspace: Bill did you what the space shuttle lunch?

Bill: I did. Spectacular!

dhara: will this be seen in mumbai india?? and if so at what time??

Bill: Yes. Peak will occur about 3:15 a.m. IST

micky: can we get to see the video of this event somewhere on

Bill: We'll post some meteor videos on the Web site.

burk:         Who was the first person to see the Leonids and observe that they were a reoccuring event?

Bill: Good question. Recurring even realized in 1833, first recorded in 585 A.D.

apollo13: How long does the shower last?

Bill: Two days

Erin: Could spectronomer analysis of the shower be useful, or are the Leonids fairly well known?

Bill: We desperately need meteor spectra, so more observations are required.

jasroy:   what time can i see the shower on the 17th in the US?

Bill: After midnight and before dawn

Harold:  Considering waiting to go out until 3 a.m. EST to catch early max. Does that make sense?

Bill: Sure

smbspace: when the next meteor storm predicted?

Bill: Next will be over eastern Mediterranean on Oct. 8, 2011. It will be a Draconid meteor storm.

startwin17:  I live on Long Island NY....what will be the best time to head over to the beach to start enjoying the view??

Bill: After midnight and before dawn

Gaea: Do we need to be in a dark site or in the city is easy to see?

Bill: Need a dark site

lihmf7:   will be posible to watch Leonids Meteor Shower from south america (brazil)?

Bill: Yes

Sky_Watcher_1978: For those of us who just can't escape the overwhelming light pollution near our homes, is there a way to "listen" to a broadcasted stream of audio where we can hear the familiar "pinging" of meteors?

Bill: Go to and see what they have. Sometimes they stream it.

IceNine: would that be the same for the whole east coast?

Bill: Yes

jasroy:   at what time in florida?

Bill: After midnight and before dawn

erickristiansen:  Which direction should I scan the sky if I am located out near the Chicago area?

Bill: Up and slightly to the east

smbspace: does earth poles see any meteors? i bet the rates are lower at the poles are they?

Bill: North Pole sees some Leonids -- South Pole sees none.

Ankh-men-Ra:   Bill, are there any reports of early fireballs like we have seen in previous Leonid showers?

Bill: Yes.

klotito:  I'm confused, is the peak to occur tonight (16 to 17th) or tomorrow night, (17th to 18th) in the northeast US?

Bill: Tonight (Nov. 16th) will be closest to traditional peak

tkibbey: I read that Leonids are offshoots from a comet. Are there such particles along the entire orbital trajectory at all times?

Bill: Yes

bluebobcat: When was the first recorded siting of the Leonids?

Bill: 585 A.D.

rangsiy: Can I see anything at 11PM?

Bill: Only background meteors. Very few Leonids. Leo has to be well above horizon.

erickristiansen:  What time should I check the skies if I am out near Rockford, Illinois?

Bill: After midnight and before dawn

Sky_Watcher_1978: I know that you have the ability to forecast meteor storms for a specific shower in future years...any predicted Leonid meteor storms in the coming years?

Bill: Not for several decades

rick: Why are some years more epectacular with higher meteor counts?

Bill: Because the Earth passes closer to streams of particles left behind by the comet in past years.

Ark: The prognostics of maxima in USA are the same for south Brazil?

Bill: Yes

trojangiant: Hey Bill, I'm in New Mexico. What time should would I be able to see them?

Bill: After midnight and before dawn

Jazzman161: Hi Bill. Is this one being called spectacular just because of the phase of the moon? Seems the storms back in 2000 would have been better.

Bill: The storms in 99, 00, 01, 02 were MUCh better. But, an outburst isn't something to ignore. :)

Jon: Have other planets been known to change meteor showers,moving debri of comets,shared/unshared space(s).

Bill: Any body with significant gravity can alter the orbit of something passing near.

egvick:   for J.Bean Shuttle might schedule to adjust launch away from meteor shower if high rate due to concern about debris impact to orbiter

Bill: No

goldfishpondmaster: i have noticed when they predict meteor showers on a certain time, me and my wife useally see meteors a day or 2 in advance of the predicted time, is this normal or is it by chance, like this morning, we were out and seen like 6-8 meteors within an hr b4 sunrise

Bill: This is normal

gatortwins:  what will this look like from space, from the astronauts on Atlantis or the ISS? like anything?

Bill: They look down and see streaks of light in atmosphere below. Kind of a different perspective!

erickristiansen:  What time is the outburst for north america, mainly chicago?

Bill: No outburst in North America

Pleiades_Sister: Will Sydney, Australia get a view?

Bill:  They won't see much. Leo will be low in the sky.

jasroy:   What is the best viewing time for me in Florida?

Bill: After midnight and before dawn

Erin: Are there scientific platforms that you would like developed, that would help you with your research?

Bill: A mile-wide orbital catcher's mitt. :) Seriously, spacecraft instruments don't make good meteor detectors because they're so small.

wrumbley: Gosh darnit, does anyone read answers to previous question?

Bill: Some do. :)

kelarg:   What's an outburst? What's it look like?

Bill: It's when the meteor rate exceeds about 150 meteors per hour, but less than 1,000 meteors per hour. You can see several meteors per minute, instead of several meteors per hour. In a storm, you see about a meteor per second.

Sky_Watcher_1978: Leonid meteors have been known to create spectacular "fireballs" rather than quick, rather faint streaks. What is the reason for why one shower produces fireballs and another shower does not?

Bill: Depends if the stream we cross is rich in big meteoroids. If yes, we have a lot of fireballs.

Jazzman161: Best date and time for the U.S., specifically Nevada, Pacific time? Have to travel a ways to get away from the lights in Las Vegas!

Bill: After midnight and before dawn

starlover: what time will i be able to see the metero shower here in houston?

Bill: After midnight and before dawn

apollo13: How long does it last?

Bill: Two days

ilovemeteors: do i have any chance of seeing them if i live in new york city? will i need to get out of manhattan? what are my best bets?

Bill: Yes, leave the city. Need a darker sky.

merryr: Have these meteors ever been known to reach ground and bits recovered

Bill: Leonids don't reach the ground, but pieces of asteroids have. But many meteorites are on display in museums. And for sale on eBay. :)

IceNine: how will the Geminids compare to the Leonids this year?

Bill: Geminids will have rates of about 120 meteors per hour. For U.S., will be the better of the two showers.

Erin: How did you become interested in studying meteor showers?

Bill: In grad school when I worked on an experiment that flew on the Long Duration Exposure Facility (LDEF).

Sky_Watcher_1978: Is there a good chance (ofcourse in perfect viewing parameters) that we could see a few actual smoke trails early tomorrow morning?

Bill: I don't expect any, but I could be surprised. :)

Michael:  Hello from Thule Greenland !

Bill: Hi Greenland!

darkskies: I live in Kentucky and it looks like it will be very cloudy tonight. Is there a way to "watch" the meteor shower online in real time?

Bill: Not as far as I know. :(

MeteorNut: If a meteor hits the space shuttle, what will happen?

Bill: A small meteor, not much. The odds of a meteor large enough to cause a catastrophic problem is EXTREMELY orbital debris or "space junk" hit is more likely.

starlover: What is a good place outside of houston to view the meteor shower?

Bill: Any place dark!

mahislayer: whats the best way to identify Leo, i have a general idea what to look for as i'n very Familiar with Orion and both dippers

Bill: Look for a backward question mark rising in the east. Head of the Lion looks like a backward question mark.

kathy: Last time I observed a fantastic Leonid display was 2001. I understand that was a "storm" and this year is not, however will the display be as colorful as 2001?

Bill: Nowhere near

guardguy87: when will people in asia be able to see it?

Bill: Yes, Asia has the best show.

wrumbley: What are max, min & avg size of Leonid meteors?

Bill: Minimum, grain of sand. Maximum, about size of golf ball. Average in between. :)

michel:  Hi Bill, did we had simular events in the past; 11 years after the comet or is this event unique?

Bill: There have been similar events.

Kianna:  How many meteors should we expect per hour? Does it depend on where you live?

Bill: 25 per hour in U.S and western hemisphere, 200-300/hr. in Asia.

Johnny: Why will there be so many more streaks in Asia than in North America?

Bill: Because Asia will be facing into the Leonids stream when Earth passes close to the 1467 and 1533 trails.

MMM:  Will the meteors be visible on the evening of November the 17th?

Bill: After midnight and before dawn

Schuster: can you settle a dispute? which day is best for the viewing tonight beginning at 12 midnight (technically Tuesday) or tomorrow beginning at 12 midnight (technically Wednesday)

Bill: The first option -- closer to traditional maximum

Michael:  Would it be possible to see something from here at 76 N 68 W ? The sun is now below the horizont until Feb. 2010

Bill: Yes, definitely

questionman: If you live on the eastcoast what time should you be on the look out

Bill: After midnight and before dawn

Jon: Do other planets have regular showers?same ones or different

Bill: Yes. Other planets have meteor showers because they intersect comet trails like the Earth. I tried to look for meteor showers on Mars using the MER rovers, but didn't see anything.

agibson: The IMO says, "The main peak(s) are expected to occur in the night of November 17 to 18 around 22h00 UT" does that disagree with your observing advice?

Bill: The IMO time on 17th translates to 5 p.m. Eastern on 17th. But, other researchers -- Maslov -- predict the traditional peak near 9:00 UT on 17th which is 4 a.m. Eastern (just before dawn). Based on this, I think best viewing will be in pre-dawn hours on 17th.

Sky_Watcher_1978: In connection with the individual whom asked a question regarding photographing the shower, what are the best settings for a digital camera in regards to ISO and aperature?

Bill: I take horrible pictures. :) All I can advise it set focus at infinity, point camera up, take exposures 1-5 minutes, and hope a meteor crosses your field of view. Have you tried Googling your question? :)

apollo13: How long is the Leonids meteor shower?

Bill: Two days

Karl: if I was in Saturn will I see some meteors?

Bill: No, you'd die on Saturn. :)

Robert: What percentage of meteors actually hit the ground? and what size are they?

Bill: Very small fraction of asteroidal meteors -- not from meteor showers -- hit the ground. Before entering atmosphere, these meteors are usually a yard or more across.

ekela: what about Guam in the Micronesia? just look up to the east too?

Bill: Yes

my3sons: Is it more visible on the West Coast of N.America than on the East Coast?

Bill: No, about the same

lihmf7:   would i be able to see this in Brazil?

Bill: Yes

MeteorNut: Are there more meteor showers visible from the northern or southern hemisphere?

Bill: Northern -- Leo is higher in the sky

Jazzman161: Do you promise that every "Wish upon a falling star" will be granted? I'm holding you to this one LOL.

Bill: My wishes come first. :)

jay721:  How long till the next Leonids? maybe I can coax the wife out of bed in the middle of the night

Bill: The Leonids occur every year in mid-November at about 15-20/hour unless there's an outburst. Maybe you should suggest to your wife that you go on a cruise to the Mediterranean in 2011 to see the Draconids meteor storm. :)

Kevin: When will the peak time be for the east? Im in Toronto

Bill: After midnight and before dawn

Lizzie: will the space shuttle be affected at all by the leonids?

Bill: We hope not. Odds are very small that a Leonids will hit the shuttle.

gsiman: if i live in s georgia which is the best direction to look in to view this event?

Bill: Up and slightly to the East

Sky_Watcher_1978: Are you yourself an avid meteor watcher? Any meteor shower from memory considered one of your favorites?

Bill:  T he 2001 Leonids as seen from Maui. Most of the time, I let my meteor cameras do the watching.

kathy: how do you determine the day/time of most intensity?

Bill: Using computer models that track particles from comets around solar system. We count how many pass near Earth each year, and that gives us an idea of how strong the shower will be.

pirodri1: Bill, you mentioned that the showers will occur anywhere between midnight and dawn in the USA. Is is possible to estimate a peak time during that span?

Bill: Very close to dawn

Erin: Is there a prediction for when the debris from Tempel-Tuttle will have dispersed and the Leonids will stop appearing?

Bill: No, not that I'm aware

Keenan_Friend: Is it possible to photograph this with an old film canon slr camera?

Bill: Yes. Take time exposures and use a 400 ASA film. I did this as a kid.

Angdromeda: Hi Bill, what is so significant about this particular meteor shower in comparison to the recent taurus shower? Also, when will be the best time to view the shower from San Diego?

Bill: Taurids are a much weaker shower, and this year, Leonids are an outburst. San Diego, after midnight and before dawn.

xxJBREEZYxx: can you see the meteor shower in Canada?

Bill: yes

llamela1:  i read somewhere that the meteors seem to originate from the constellation Leo, is that correct? Would that be a good place to look tonight?

Bill: Yes, it is. Look up and slightly to the east after midnight.

ello_govna: Hello :) I read if you live on the east coast the best time to view is between 1 A.M. and 5 A.M. Is that true?

Bill: Yes

Dimosthenis: do airplanes are in danger thru all this?

Bill: I saw one paper that put the odds of a meteor striking a plane at 1 in 100,000 over 100 years. I think we're pretty safe :)

(Moderator) Brooke: We have time for a couple more questions. Incredible questions, everyone!

jmtroc:  is the metor shower tonight? or tomorrow

Bill: Both - but I think tonight will be better.

klotito:  what compass direction is mars in the night sky at midnight if I am in the northeast US?

Bill:  Look to the East - you'll see a bright, reddish star, which will be Mars.

(Moderator) Brooke: That wraps it up! Thanks to our guest, Bill Cooke, and to our audience! Enjoy the meteor shower, everyone! Want to know more about the Leonids? Visit this great link from Science@NASA!