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Total Lunar Eclipse: 'Up All Night' With NASA!
(Moderator Jason): Welcome to today's Web chat with NASA expert Dr. Rob Suggs. Our topic today is the exciting solstice lunar eclipse that’s happening tonight! Please remember to stay on topic. This is a moderated chat. It may take a few moments for the queue to catch up to your question, so please don’t leave if you don't see your question right away. We're getting setup right now and will start answering questions in just a few minutes. In the mean time, you can go ahead and ask your questions by typing out the question in the yellow box at the bottom of the chat window and clicking on the 'Ask' button on the right. Thanks for your patience.

Rob: Hi everyone, Rob here! Welcome to the lunar eclipse chat. Looking forward to your questions. I'd like to start with some general information about where the eclipse can be seen -- and not seen -- tonight. Sorry for the length of this. It's a big world. :) Early in the morning on Dec. 21, a total lunar eclipse will be visible to sky watchers around the world. The eclipse is visible across all of North America -- for viewers in western states, the eclipse actually begins late in the evening of Dec. 20. Viewers in Greenland, Iceland and western Europe will be able to see the beginning stages of the eclipse before moonset. In western Asia, the later stages of the eclipse will be visible after moonrise. All of the eclipse will be visible throughout Mexico and Central America and northwest South America. Viewers in Peru, Chile and Bolivia will see most of the eclipse, but the moon will set before the end of the Penumbral phase. Viewers in Brazil will see the moon set during totality. Parts of Africa in the northwest will also see the moon set while it is eclipsed. All but the westernmost tip of Australia will see an eclipsed moon as it rises. Unfortunately most of Africa, the middle East and India will not have a view of this event.

Rob: Also, this map is VERY useful in helping you determine how to see if you'll be able to see the eclipse tonight:

paddle: Do you know if a standard camera (with or without zoom lens) will be effective in capturing images of the eclipse tonight?

Rob: It's better with a zoom because the moon is fairly small, but it's worth trying with any kind of camera. You may have to try different exposures to get it just right. DSLR will work well because they typically have a spot metering capability, and you can adjust the settings.

lindabeamon2010: I live in Las Vegas and I just want to see it. It is very cloudie here can't see.

Rob: That's a shame! Try the cameras that we'll have linked here on the page tonight. Hopefully someone will have clear weather!

Matt_Watkins: My question is when will totality be on the east coast?

Rob: Eastern time mid-eclipse is 3:17 a.m. EST.

lisa3286: i saw the article on that the eclipse was going to "have a twist", but i didn't read into it yet.

Rob: Probably because it's on the solstice, so the moon is as high in the sky as it can possibly be. Really optimizing the viewing.

paddle: ok great, will use a tripod.

Rob: Yes, that's a good thing!

pb: hi writing in from India...have been reading online and i think am thoroughly muddled up with the time zone conversions! 18:30 pm there was a beautiful full moon and just one bright star and by the time i got my camera out was in darkness...and trying to figure whats happening?pls help....ive read online the eclipse is visible only in america but whats happening here in india?

Rob: Unfortunately, you won't see this eclipse in India. :( But there will be a total lunar eclipse June 15, 2011 that you should be able to see.

Sparticuz: 'early in the morning' isn't very exact...any times?

Rob: See if this helps:

vaishnavi.shyam: I only bank on the video that is going to be provided by NASA website. Its quite cloudy.

Rob: It's cloudy for our sites -- we hope it will clear. Also, the Space Station crew is aware of the eclipse and will take pix if they have time.

thewisdomchicken: Oh, I live in Sweden.

Rob: Sweden will have a view at moonset.

pirateducky: It's cloudy here in Seattle as well. Hoping it will clear up tonight.

Rob: Good luck -- we hope so, too!

nora: So, it is the solstice that makes the event rare -- or the full moon??

Rob: The solstice -- all lunar eclipses occur at full moon.

Marion: What causes the weird colours we're going to see for this eclipse?

Rob: It's the sunlight passing through the Earth's atmosphere and red light scatters through the atmosphere more efficiently. On the moon, you'd see all sunrises and sunsets on Earth at the same time!

aaron_gilbert: How often does a full lunar eclipse fall on a solstice? Is it rare?

Rob: The last time was in 1638 -- Galileo was alive then! The next will be in 2094. This is a special event!

warren65: Are we closer to the sun and farther from the moon at the same time?

Rob: Nothing special right now -- we're closer to the sun in early January and furthest in July.

Rae94: Will the eclipse be visible in Alberta, Canada? If so, at what time?

Rob: Yes, Alberta will see the eclipse. Pacific Time? That would be 11:41 p.m. and 12:53 a.m., PST.

astronerd: How many eclipses have you personally seen?

Rob: Me personally, about half a dozen lunar eclipses.

Kevin: When's the next full solar eclipse?

Rob: Solar, not lunar, will be... partial in January and partial in July. In 2012 there will be a total solar eclipse.

athompson15: When would be the best time to view the eclipse from indiana?

Rob: Depends on if you're Eastern or Western Indiana:

CSM_: How long does a total lunar eclipse last?

Rob: The moon will be totally eclipsed for about an hour.

larrytheadman: Alberta is Mountain Time.

Rob: Okay that will be 11:33 p.m. on Dec. 20 (tonight), going to 3:01 a.m. on the 21st.

bagel085: Will miami be able to see the eclipse?

Rob: Yes, Miami can see the eclipse if the weather is clear. Check the Eastern time on this chart:

tgyori: Is it more spectacular when it falls on a soltice?

Rob: No, it's just an astronomical coincidence. It will take place when the moon is at it's maximum northern position in its orbit.

Teresa: Where do I go on this site to watch this? I live in Montreal, Quebec Canada right now it's cloudy.

Rob: Try coming back to this page later tonight -- we'll have some live cam views listed, and we're hoping the weather cooperates.

space_luver123: What time would US be able to see the solstice?

Rob: This is a great chart to determine that:

Barb: How often do we have lunar eclipses?

Rob: From the year "0" to 2999, there are 7,245 lunar eclipses, of which 2,089 are total in the umbra and 2,536 are partial in the umbra, and 2,620 are penumbral.

Libby: Is this the first time you are doing this web chat thing?

Rob: No, I've done a couple of others and I really enjoy them!

keevviin: Will san fransisco california be able to see this event?

Rob: Yes, check this chart for Pacific Time:

Rob: Hey everyone -- thanks for the patience. We have about 200 questions in queue. :) Great that there's this level of interest. For more information about your local viewing times, this is a great link:

aaron_gilbert: No need to respond, this is so cool! thanks for taking the time Dr. Suggs, and thanks to NASA for setting this up.

Rob: Very welcome. :)

Batman: Does this eclipse effects people or nature in any specific way?

Rob: Not that I'm aware of.

juanfromcolombia: Greetings from Colombia, National university astronomy school.

Rob: Greetings, Colombia.

sdfa: Will this be worth staying up late for to see?

Rob: If the weather is clear, definitely. A solstice total lunar eclipse is pretty rare.

Excitedforeclipse: That chart breaks everything down perfectly! Thank you!

Rob: Very welcome!

Nate: What time will the live cam views come on ?

Rob: About 5 p.m. EST.

thewisdomchicken: What is a solstice?

Rob: It's a point on the ecliptic when the sun reaches either its northernmost or southernmost point relative to the celestial equator. What that means for us on Earth is that after the winter solstice, the days start becoming longer.

suggs: Greetings from Italy. We hope to enjoy the live cam!

Rob: Greetings, Italy! Good luck on the viewing.

galacticgirl: I know what happens during a solar eclipse, but what exactly happens during a lunar eclipse?

Rob: The moon travels through the Earth's shadow.

space_luver123: Why does the moon change color during the solstice?

Rob: It's the sunlight passing through the Earth's atmosphere and red light scatters through the atmosphere more efficiently.

fstone: How long will the eclipse last?

Rob: About an hour, at 72 minutes for totality.

(Moderator Jason): We're working to answer your great questions. Keep them coming! To submit your own question, please type it in the box at the bottom of the window and click the 'Ask' button on the right side of the box. Thanks for your patience as we answer your questions.

Libby: Are there L.E. during the day but we just cant see them?

Rob: They are, but you're on the part of the Earth not pointed at the moon, so for example, to the folks in India, it's happening during their daytime, but the moon isn't up.

Rob: Hey everyone -- for the live cam information, that will be linked here around 5 p.m. EST. So return back to this chat page:

Excitedforeclipse: How are you able to determine when an eclipse will take place?

Rob: Computers and complicated math! Orbital mechanics and physics of planetary motion are well understood and computer programs can simulate so that we can predict these very far into the future.

DevinCharles: Are there any tidal anomalies when the three bodies are aligned?

Rob: That's an interesting question. There are maximum tides with that alignment.

CSM_: Can you re-post the time chart? Also, where in the sky will the moon be when the eclipse starts?

Rob: Absolutely:

janet_anderson: Will the astronauts on the International Space Station be able to see the eclipse?

Rob: Yes, and in fact they're hoping to make photos if time permits.

Libby: Has the color that the moon turns during an L E always been brownish reddish greyish and orange?

Rob: I've seen mentions of bluish colors at times, also pale yellow and silver. It just depends on the state of the atmosphere at the Earth's limb at the time of the eclipse.

lokol: Will we just have to refresh this page at 5p.m. EST to get the live feed or will it be a seperate link?

Rob: Just refresh -- it will be on this page. If we get other cameras going, and we hope to, we'll have a separate page.

Sara: Has it really been a few hundred years since the last total lunar eclipse occured during a winter solstice?

Rob: Yes, it was 1638.

Libby: Is the moon getting bigger?

Rob: No, in fact it's getting smaller in the sky. Very slowly, it's moving farther from the Earth. It mass isn't changing.

Teresa: Are there any events that are suppose to happen on December 21, 2012?

Rob: There are no eclipses in December of 2012.

Art64: What would happen if there were any astronauts present on the moon during the eclipse? Would they disappear?

Rob: Hahaha! They wouldn't disappear. :) It would get dark and colder. The temp swing is about 500 degrees F from daytime to mid-eclipse on the moon. But they'd get to see a ring of color around the Earth, which is all of the sunrises and sunsets of Earth at the same time.

Sebastian: Do lunar eclipses only happen at the descending node of the lunar orbit?

Rob: It's very close to ascending or descending node.

s.mace: What time will be start of the lunar eclipse?

Rob: This is a great link for that:

(Moderator Jason): Thanks for all the great questions so far. Keep them coming! To submit your own question, please type it in the box at the bottom of the window and click the 'Ask' button on the right side of the box. Thanks for your patience as we work to answer all of your questions.

CSM_: How many lunar eclipses happen in an average year?

Rob: On average, about 2.4 per year. That includes all lunar eclipses, both partial and total.

abigator: Hello! I have a question. so, the penumbral eclipse starts at 130, and the total eclipse starts at 240. If a group of teenagers wanted to watch the eclipse, what part will be the most noticeable? the moon darkening or the moon turning red?

Rob: The partial phases are also worth viewing. Within that time frame, something interesting will be happening!

PHLMoonWatcher: Rob... I love the bit about all the rises and setses all at the same time. Nice.

Rob: I didn't come up with that, but that would be amazing to see.

eee: What time will the moon turn red CST?

Rob: It will begin at 12:30 a.m. CST and should be totally red by 1:41 a.m. Central.

Libby: Where does all the water in the ocean go in low tide? my mom wanted to know.

Rob: It rushes over to cause a high tide somewhere else in the world.

magembe: hi am in Tanzania - africa, at what the event will be seen here?

Rob: Unfortunately, only northwestern Africa will be able to see this eclipse.

jabjum: Will the pollution in the earths admosfeer affect the color of the moon during the eclipse?

Rob: Perhaps, but volcanic dust is a more important influence on the color.

keevviin: Is there going to be meteor showers tonight also?

Rob: Nothing significant. There's often a minor shower happening in the skies.

CSM_: Which continent willl have the best view of the eclipse?

Rob: Definitely North America on this round.

luizf: How will be the visibility in the capital of Brazil?

Rob: They'll see it at moonset, if the weather is clear.

magembe: Can i see this online?

Rob: Yes, there will be a live cam embedded later on this page -- we're hoping for clear weather.

WizardSleeve: Tonight is also winter solstice, what effect does this have on the lunar eclipse?

Rob: It just means the moon is farther north than usual, making it higher in the sky.

MBB: About how often do they hapen?

Rob: About 2.4 times per year, partial and total.

CalSL: Hi! Will the eclipse look similar to us and the ISS crew?

Rob: Yes, they should see the same thing but will have less time to look at it than those on Earth.

Art64: Will all the animals that use the moon for direction at night get lost or die during the eclipse?

Rob: Animals that depend on moonlight to see prey will definitely not be able to see as well because the moon will be much fainter.

keevviin: How long will the event occur in north america?

Rob: About an hour at 72 minutes -- and that's for totality. About 3.5 hours that you can tell something is happening.

Sebastian: Can two lunar eclipses occur in the same month?

Rob: Sometimes two successive full moons can give rise to the lunar eclipse, but they would be partial eclipses only. Examples are the penumbral eclipses of June 1991 and July of that same year. Note that's a lunar month, not a calendar month.

arbiter: Will everyone see the same color effect of the moon? or will it change depending on location?

Rob: It's the same for everyone.

magembe: Is there any side effects watching the event?

Rob: Only lack of sleep and sleepiness the next day. :)

Zedex: Will the weather affect the good view of the Eclipse? Or is it generaly pretty easy to see?

Rob: You must have clear weather or at least breaks in the clouds to see it.

user: What is the URL for the lunar eclipse stream?

Rob: It will be here:

Rob: Hey everyone -- this is great! Love the good questions. Try this link to determine your best local viewing time:

Griffin: what is the longest lunar eclipse on record?

Rob: It was 236 minutes, July 16, 2000.

arbiter: If I am right the Earths shadow is a cone and the moon just falls within that cone. Does the winter solstice change the cone in any way? Does it change the effect it will have on the moon?

Rob: It doesn't change the shadow cone, it just puts it higher in the sky in the northern hemisphere. So there's no noticeable effect.

sarah: Why would the length of time the eclipse lasts change? If it's going staight across the middle vs. across the top or bottom of earth's shadow?

Rob: It's two things. One is does it go directly across the center of the umbra, and the other has to do with where the moon is in its orbit. If it's near apogee, it's moving more slowly across the sky, and if that occurs during an eclipse, that makes it a longer eclipse.

EclipseLover: What country owns the moon?

Rob: By international treaty, no specific country owns the moon.

mf: will the eclipe be visable in the uk?

Rob: Western Europe will be able to see the beginning stages of the eclipse before moonset.

Xenon: Will the people who live on the moon see the earth disappear tonight?

Rob: If you lived on the moon, you'd see the sun disappear.

mira: will utah be able to see the lunar eclipse tonight?

Rob: Yes, if the weather is clear. Everyone might want to take a look at this map, too:

Griffin: What is apogee?

Rob: It's the point in the orbit where the moon is farthest from the Earth.

sammut42003(Q) moonset means before morning?

Rob: Moonset is when the moon goes below the horizon, which will also happen in the morning because it's a full moon.

jpd: Thank you Mr Suggs.

Rob: My pleasure -- these are very nice questions.

jpd: Hi I'm Joey and I am 8 and from the UK. Will I be able to see the eclipse from Leicester?

Rob: Yes, Joey, western Europe will be able to see the beginning stages of the eclipse before moonset. Happy viewing!

WizardSleeve: I've noticed that you have recorded over 200 meteoroid impacts on the moon, roughly what size was the largest meteor to impact?

Rob: About the size of a bowling ball.

Rob: Everyone, this is where we'll have a link to the live camera later today:

mira: Too bad that it's snowing here, looks like I won't bee seeing the lunar eclipse tonight.

Rob: The clouds are moving in here tonight, too, and we're expecting rain. Disappointing!

CSM_: When was the last total lunar eclipse?

Rob: It was Feb. 21, 2008.

Squeezle: Is this full moon unique in any way compared to previous ones? If so, what sets it apart? If not, how often is this cycle?

Rob: It's as far north as it ever gets. While that's not uncommon, it will make the lunar eclipse viewing better.

Cheese: Is the moon moving closer or farther away from the earth, or neither and what are the consequences?

Rob: It's moving farther away, which slows Earth's rotation by a miniscule amount.

Cheese: Do total lunar eclipses happen only around 21st?

Rob: No, they can happen any time of the month as long as there's a full moon.

Libby: Where are you writing from Rob? i know its NASA but where is NASA?

Rob: We're at Marshall Space Flight Center in Huntsville, Alabama.

Photosbykev: Isn't this the first lunar eclipse on the winter soltice for a long time ?

Rob: Yes, last was in 1638 when Galileo was alive.

Charlotte: Does a eclipse change anything on earth or on the moon?

Rob: The moon will cool significantly during the eclipse, about 500 degrees F.

Klepto: Hello from Russia from all amateur astronomers! :) It's very bad, this eclipse is not visible in moscow :(

Rob: Hello Russia! You should be able to see another one on June 15, 2011, and it will be much warmer then!

dima125: Are there benefits for observing the moon by small reflecting telescope during moon eclipse?

Rob: With a telescope you can watch the Earth's shadow as it crosses various lunar features.

Rob: Everyone, this is a great link to determine your local viewing time:

wobblyearth: In what way might the lunar eclipse affect the earth's gravity?

Rob: There's no noticeable effect on the Earth's gravity.

Squeezle: Is there any change to the magnet fields of the earth or moon that results from the specific location of the moon? Or is it the same as any other day?

Rob: Also no noticeable effect.

chptsa: Do you guys expect to have the eclipse visible with the live feed camera? The weather all over the country is seemingly very uncooperative for the event =(

Rob: We're hoping for a break in the weather here. The ISS astronauts are also aware of this and we're hoping for some images from them.

Mr_Curtian: woulda 100x magnification telescope be good for vewing the eclipse or a 50x?

Rob: Start with 50X.

Rob: Hey everyone -- we're about to finish up the chat here in a moment. I wanted to leave you with this information. A viewing chart: And the charts for your best local viewing times: Also, come back to this page around 5:00 EST for a link to a live Web view of the skies. We're hoping for a break in the weather:

Rob: Finally, thank you for these fantastic questions. Please make plans to return to this same page tonight at midnight EST. NASA astronomer Mitzi Adams will be here until 5:00 a.m. EST to watch the eclipse and take your questions. Have a great afternoon!
Janet Anderson, 256-544-6162
Marshall Space Flight Center, Huntsville, Ala.