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d14238: can someone tell me the best time to see the meteor shower
Rhiannon_Blaauw: 1 am to 3 am local time.

Brooke: Hello to everyone just now joining the chat! Here are some viewing tips from our astronomers. Go out to an area where there is as little light pollution as possible, and give your eyes some time to adjust. It often takes 45 minutes for your eyes to fully adjust to the dark. If your area has poor weather, unfortunately there isn't much use in trying to see Geminids live, BUT you can check our our live Web cam: http://www.ustream.tv/channel/6539981 Most of the world is positioned for a great view of the Geminids. Only if you live below 50 degrees (South) latitude are you unable to see the Geminids, which rules out antarctica. For those that live around the equator or in the northern hemisphere, the best time to see the Geminids is between 1am and 2 am local time, though you should be able to see plenty all night long. After you have given your eyes time to adjust to the dark, just look straight up, be patient, and then enjoy.

foo: What is observed if a meteor "skip"s off the atmosphere?
Rhiannon_Blaauw: The closest to what you are getting at would be called a 'grazer', where the meteor comes in at a very low angle and just 'grazes' along and lasts a while. Even grazers will usually get completely ablated in the atmosphere and not 'skipped off' though.

CLAYSAYS84: how close are meteors when they pass by?
Rhiannon_Blaauw: The Geminid meteors burn up about 75 kilometers, or 47 miles up, the lowest recorded Geminid is at 35 km, or 22 miles up.

nicool: what are the meteors generally made up of? and you said they are mm to cm in size as they reach earths atmosphere? how can something so small produce so much light?
Danielle_Moser: Meteoroids are generally made of rock and ice. Typical sizes of Geminid meteoroids are mm - cm sized particles, you are right. It's pretty amazing that something so small produces so much light, isn't it? But these particles are moving EXTREMELY fast, about 80,000 mph. Technical answer: As the meteoroids plow into the atmosphere they collide with many, many air molecules and this strips away the outer layers of the particle. In subsequent collisions electrons are knocked into higher orbits. When the electrons fall back down to their rest positions, light is emitted and we see it as a meteor.

CLAYSAYS84: Are we able to hear any of the metors as they burn up?
Rhiannon_Blaauw: Yup! If you turn up the audio on the ustream video you may hear chirps and whistles. The meteors ionize the air around them as they burn up and these ionized air molecules reflect radio waves back to the radio. As the meteor moves, the frequency changes, which accounts for the various sounds. Some people have been known to hear meteors with their own ears while observing them. The meteors will have to be very low though, in order to be heard that way.

tomthx: Sorry I arrived late and have seen a few flashes on live stream which is great. I have been reading up about the shower, since reading the NASA tweet yesterday, and would like to know the best time to view the shower in Sydney Australia?
Danielle_Moser: Well, the peak time was between 1 and 3 am local time on the morning of Dec 14. But you can still see meteors Dec 14-15, though the rates will be somewhat reduced.

Q: what could make the shower heavier except thecomet pass ?
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Tania: NASA thanks for the transmision , we saw an imagen like the earth or moon, what was that?
Danielle_Moser: The USTREAM briefly tapped into the feed from the International Space Station.

view3dtv: hi thanks for being there... in baltimore md how much does the shower trail off the next few days?
Rhiannon_Blaauw: It will trail off considerably. Tomorrow night you may see 30-50 meteors per hour, and then the next night it *may* be half of that again. But keep in mind that these meteor showers occur often! The Quadrantids are at the beginning of January and are quite a nice shower as well.

SouthTexas101: That was the biggest one yet looked like a tennis ball in size. wow!
Rhiannon_Blaauw: We've seen a couple beauts here as well!

Brooke: Thanks for the fantastic participation everyone! Really appreciate all of the great comments and questions. This is shaping up to be a terrific night for Geminid-viewing. We're entering the last half hour of our "up all night" chat, so please send your final questions to Danielle and Rhiannon. Thanks much.

sara: So glad for the live feed, as Los Angeles is covered in a thick blanket of fog, the likes of which I can't ever recall seeing... Of course if I was up in the hills or even near the mountains, I don't know if the weather would be any different... but glad I've caught a few here on the live feed
Rhiannon_Blaauw: Glad you can watch here, Sara. But I'm disappointed LA is covered in fog!

WB8ELK: Could only stand to be outside for 5 minutes (can I borrow a Space Suit?)....but I saw 10 good ones in that time...approx 2 per minute at the moment. Is the audio on your feed coming from bursts from the NAVSPASUR radar? - Bill in Madison AL
Danielle_Moser: Pretty cold for AL, eh? :-) The audio feed is from the forward scatter radar system here at Marshall Space Flight Center. Take a look at http://www.nasa.gov/offices/meo/outreach/forward_scatter_detail.html

Aziza: what could make the shower heavier except thecomet pass ?
Rhiannon_Blaauw: The shower stream may be moving closer to the earth's orbit due to various gravitational affects.

Hodgetucson05: I'm in tucson and it is 2:17 AM, have I missed the action?
Rhiannon_Blaauw: Nope! Go outside and look... you should still see lots. Let us know if you do see many!

nicool: Thanks so much for all the info tonight! this was really cool hopefully I'll catch some tomorrow! have a great night, all
Rhiannon_Blaauw: You too! Thanks for joining us!

view3dtv: Do the astronauts on the ISS have a good view of the meteor shower?
Rhiannon_Blaauw: The astronauts on the ISS could potentially see Geminids. However they are orbiting at 250 miles up, and the Geminids ablate at about 47 miles up, so the astronauts would have to look down instead of up.

BEN: what is the black point in the bottom right of the video feed? and which way is north on the feed?
Rhiannon_Blaauw: The black point is a defect of the camera, unfortunately.

NYC_Watcher: Is the live feed being recorded and will it be available for download?
Rhiannon_Blaauw: No, however if you go to fireballs.ndc.nasa.gov you will be able to see videos of bright Geminids over the next few days! Also, the ustream video should still be up tomorrow night for your enjoyment.

cyber5: Do any of the Radio telescopes pay attention to meteor showers? Can they tune into them, or are they too close?
Danielle_Moser: Indeed they do, though some showers aren't ideal for observing with a radio telescope, due to their size/speed (ie the Canadian Meteor Orbit Radar (CMOR) doesn't observe many Perseids since the stream has a lot of larger particles).

like_to_know: Would you be able to see the show from the space station?
Danielle_Moser: Yes, when ISS is on the night side of the Earth astronauts can look down and see meteors ablate in the Earth's atmosphere from above.

ThePeacePixie: So do we only see reflections of light bouncing off each meteor from the sun- like the moon, persay; or do we only see the light emitted from combustion of each meteor in our atmosphere?
Rhiannon_Blaauw: The second option. What we see is the burning up, or ablating, or ionization of the particles in the atmosphere. When the meteoroid hits the atmosphere, electrons pop off the atoms. This is called ionization. While the particle itself may be only an inch across, the ionization trail can be many feet across.