First Evidence of Supernovae Found In Ice Cores

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First Evidence of Supernovae Found In Ice Cores

Posted by kdawson on Monday February 23, 2009 @02:44PM from the hot-and-the-cold-of-it dept.

KentuckyFC writes "Supernovae in our part of the Milky Way ought to have a significant impact on the atmosphere. In particular, the intense gamma-ray burst would ionize oxygen and nitrogen in the mid to upper atmosphere, increasing the levels of nitrogen oxide there by an order of magnitude or so. Now a team of Japanese researchers has found the first evidence of a supernova's impact on the atmosphere in an ice core taken from Dome Fuji in Antarctica. The team examined ice that was laid down in the 11th century and found three nitrogen oxide spikes, two of which correspond to well known supernovae: one event in 1006 AD and another in 1054 AD, which was the birth of the Crab Nebula (abstract). Both were widely reported by Chinese and Arabic astronomers at the time. The third spike is unexplained, but the team suggests it may have been caused by a supernova visible only from the southern hemisphere or one that was obscured by interstellar dust."

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The Crab Nebula wasn't born in 1054 AD by unassimilatible · 2009-02-23 14:53 · Score: 3, Insightful

1054 AD, which was the birth of the Crab Nebula

The Crab Nebula is 6,500 light years away from earth (http://en.wikipedia.org/wiki/Crab_Nebula).

This means the birth of the Crab Nebula was in the year 5446 BC. Mankind witnessed it 6,500 years later.

News stories on such phenomena invariably leave out this little fact, i.e., that which is witnessed by man in the sky usually happened thousands of years earlier than when he actually saw it. This makes it confusing for the average reader.

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1. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-23 15:00 · Score: 3, Insightful
  
  But isn't it more sensible when speaking in a historical tone to refer to a celestial objects birth relative to our time line and not the objects actual birth?
  I suppose it would be astute to word it in the tune of, "1054 AD, which was when man observed the Crab Nebula". This isn't accurate either as it may suggest that the Nebula could have existed prior to the observed date. ::shrug::
2. Re:The Crab Nebula wasn't born in 1054 AD by khallow · 2009-02-23 15:01 · Score: 3, Informative
  
  There's a good reason to leave that fact out. It doesn't have bearing on the story. And your date is too precise. I don't know if we know it's position and motion well enough to determine how far away the Supernova was to the nearest year.
3. Re:The Crab Nebula wasn't born in 1054 AD by adamchou · 2009-02-23 15:14 · Score: 1
  
  It doesn't have bearing on the story. And your date is too precise.
  I beg to differ. Although I agree with you that it isn't important to get across the subject at hand, it is still very important. If this was something posted up on Yahoo!'s front page, then fine, I can understand. The layman doesn't care about these details.
  However, this is being posted on an astro physics website. It may be overly detailed but if you're going to be detailed, you need to be correct. This is especially so when your audience is a bunch of scholars, scientists, and enthusiasts that are in the know and recognize glaring mistakes like this.
  when I read that sentence, the first thing that came to my mind too was "wait, what?!"
4. Re:The Crab Nebula wasn't born in 1054 AD by Cyberax · 2009-02-23 15:21 · Score: 5, Funny
  
  That's because it's CORRECT. There's no such thing as 'absolute time'.
  1054AD _was_ the time of birth of the Crab Nebula from _our_ point of view.
5. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-23 15:22 · Score: 5, Insightful
  
  You seem very confused about reference frames. There's no "fixed" time reference for the universe, so it seems perfectly reasonable to use the one on Earth where all the readers live. Sure it give jerks like you something to complain about, but the rest of us understand exactly.
6. Re:The Crab Nebula wasn't born in 1054 AD by zappepcs · 2009-02-23 15:24 · Score: 4, Insightful
  
  Try: 1054 A.D. which is when man observed the birth of the Crab Nebula
  One thing I'm curious about. Does this mean that we admit freely that extra-solar events affect the climate of this planet? Anyone have a slide rule handy and some star charts or galactic weather maps? Can we calculate probable effect on current climate conditions from extra-solar events?
  
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7. Re:The Crab Nebula wasn't born in 1054 AD by mR.bRiGhTsId3 · 2009-02-23 15:30 · Score: 1
  
  The relative motion of a celestial body is easily determined by the red/blue shift of its emission spectrum.
8. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-23 15:40 · Score: 0
  
  But the universe didn't exist before 4004BC, that doesn't add up!
9. Re:The Crab Nebula wasn't born in 1054 AD by MichaelSmith · 2009-02-23 15:40 · Score: 2, Insightful
  
  the birth of the Crab Nebula was in the year 5446 BC. Mankind witnessed it 6,500 years later.
  Traveling at the speed of light no time passed between the explosion and the observation at Earth. So the explosion really did happen in 1054.
  
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10. Re:The Crab Nebula wasn't born in 1054 AD by jmizrahi · 2009-02-23 15:49 · Score: 3, Insightful
  
  The whole point of relativity is that there is no such thing as absolute time. Your statement assumes that there is meaning to simultaneity, which is incorrect.
11. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-23 15:51 · Score: 1, Interesting
  
  It's been heavily studied and ruled out as a major cause of global warming, however, it's not my field of study, so I can't say much more.
12. Re:The Crab Nebula wasn't born in 1054 AD by techno-vampire · 2009-02-23 15:57 · Score: 4, Insightful
  
  This means the birth of the Crab Nebula was in the year 5446 BC. Mankind witnessed it 6,500 years later.
  AIUI, it's customary in Astronomy to ignore the time it took for the light to reach us and consider that things in the sky happen when we see them happen. Not that they're not aware of it, it's just that it makes things easier to talk about, especially to laymen. In general, people either understand about the time lag and take it for granted, or neither understand nor care.
  
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13. Re:The Crab Nebula wasn't born in 1054 AD by Cyberax · 2009-02-23 16:13 · Score: 1, Insightful
  
  No. I know perfectly well that all inertial frames are equals.
  I object to parent's statement that the true birth of the Crab Nebula was in 5446 BC. It just makes no sense because it assumes that time is absolute.
  Also, why 5446 BC? The Earth (and the whole Solar System) moves relative to the Crab Nebula, so we need to compensate for the time dilation. It'll be small, but it's there.
  And it gets even more fun if you are talking about quasars and remote galaxies when you need to consider effects of space expansion.
14. Re:The Crab Nebula wasn't born in 1054 AD by sleeponthemic · 2009-02-23 16:13 · Score: 1
  
  That's because it's CORRECT. There's no such thing as 'absolute time'.
  1054AD _was_ the time of birth of the Crab Nebula from _our_ point of view.
  Point of view is contentious, after all, our point of view should take into account the knowledge of the time taken for the photons to reach us.
  
  Seems strange to have modded the parent down to troll - considering the validity of the point being made.
  
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15. Re:The Crab Nebula wasn't born in 1054 AD by novakyu · 2009-02-23 16:17 · Score: 1, Troll
  
  There's no "fixed" time reference for the universe, so it seems perfectly reasonable to use the one on Earth where all the readers live.
  Well, while the special relativity may claim that all inertial reference frames are equal, the general relativity—especially the Big Bang theory—suggests that there *is* one inertial reference frame that is more equal than others: the rest frame of the cosmic microwave background radiation, which could be termed the "inertial reference frame for the universe".
  Having said that, yes, we should give the dates for when the events were observed on Earth. The universe may not revolve around earth (earth is not even at the inertial reference frame of the universe), but it sure gets confusing if we start dating events by when they actually happen, since then, in order not to get utterly confused, one must know how far this Crab Nebula (or any other intra-galaxy or deep-space objects) is.
16. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-23 16:21 · Score: 0
  
  Seems like you're the one confused by reference frames. In Earth's reference frame the Crab Nebula was born around 5446 BC. All the "no fixed time reference for the universe" thing says is that there are *other* reference frames for which the answer wouldn't be 7455 years ago. But even if you found one for which the answer was 955 years ago, you still couldn't call it 1054 AD because the unit "AD" implies Earth's reference frame.
17. Re:The Crab Nebula wasn't born in 1054 AD by indi0144 · 2009-02-23 16:23 · Score: 1
  
  meta-wooosh?
18. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-23 16:28 · Score: 0
  
  Your version may have been close to the original version, before the editor got his or her hands on it. That's when a few pedantic sentences fell on the newsroom floor, so to speak.
19. Re:The Crab Nebula wasn't born in 1054 AD by jmv · 2009-02-23 16:28 · Score: 1
  
  He is technically correct. Even from our reference frame, the supernova was ~7,500 years old. The time of an event doesn't change with it's location, only with the velocity of the observer. For any observer in the galaxy which is stationary wrt the Earth, the time of the supernova is the same. But for an observer on earth moving close to the speed of light, the time of the event is different from ours.
  
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20. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-23 16:33 · Score: 0
  
  1054AD was the time the signal arrived, from our point of view. 5446BC was the time the signal originated--the birth of the crab nebula--*from our point of view* as well. That's what it means to receive a signal at light speed.
  An observer in a different frame of reference may observe different times, but those are the times from our point of view.
21. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-23 17:15 · Score: 2, Insightful
  
  Point of view is contentious, after all, our point of view should take into account the knowledge of the time taken for the photons to reach us.
  Correct! In fact, one could accurately say that 1054 AD was the birth year of the Crab Nebula from the point of view of the photons!
  Since they are traveling at the speed of light, all points along their path occupy the same time. Hence, 1054 AD on Earth coincides with the birth of the Nebula. The summary is photocentric.
22. Re:The Crab Nebula wasn't born in 1054 AD by ankhank · 2009-02-23 17:17 · Score: 4, Informative
  
  It appears a nearby supernova could affect the climate, by ending it:
  Dec 1, 2005 ... Is there a possibility that a nearby star could go supernova and destroy the earth? Or have other bad effects on us? ...
  imagine.gsfc.nasa.gov/docs/ask_astro/answers/980521a.html
  They said, in part:
  If you are talking about the life on Earth, then there is a detailed calculation of the risks due to a nearby supernova on the web:
  http://stupendous.rit.edu/richmond/answers/snrisks.txt
  The author concludes that a supernova has to be within 10 parsecs (30 light years) or so to be dangerous to life on Earth. This is because the atmosphere shields us from most dangerous radiations. Astronauts in orbit may be in danger if a supernova is within 1000 parsecs or so.
  No stars currently within 20 parsecs will go supernova within the next few million years. ...
23. Re:The Crab Nebula wasn't born in 1054 AD by Skyth · 2009-02-23 17:35 · Score: 1
  
  That is not how time and the speed of light work. From the reference point of people on earth, we Witnessed it in 1054. It went supernovae ~6,500 years before 1054. Depending on which reference point you are claiming... your first sentence comes close to something that makes sense... but no matter what reference point you take, the supernovae still happened ~6,500 years earlier than 1054 to someone standing on earth.
  
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  Nerd.
24. Re:The Crab Nebula wasn't born in 1054 AD by Entropy2016 · 2009-02-23 17:36 · Score: 4, Informative
  
  No. Assuming the resesarch is all legit & valid (I don't feel like carefully reading their methods right now), this still isn't relevant to Global Climate Change because this didn't affect climate.
  You've got short term weather. Then you've got the average/trend of weather over very long periods of time, which is the climate. A 3 year (eyeballing it from the graph) spike in nitrogen oxide concentrations isn't considered climate. An effect on Earth, yes it appears that way, but not one that yields biological consequences. That burst vanished as quickly as it appeared. This sorta of stuff isn't even close to causing mass extinctions or new selection pressures.
  Besides, the CO2 and other greenhouse gas emissions correlating pretty nicely with with the effects we're seeing, I'm not aware of any spikes in the temperature record that we need gamma ray bursts to explain.
25. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-23 17:48 · Score: 4, Insightful
  
  Glaring error? Frankly, I thinking giving 1054 AD as the birth of the Crab Nebula is the most precise way of pinpointing that event. We could have obtained absolutely no information about the event before that date anyhow.
  Given general/special relativity, appealing to some objective background time and saying that the supernova occurred "simultaneous" to events in 5446 BC on Earth is the truly ridiculous claim on a cosmic scale. To another equally valid observer, those two events are not simultaneous, and could be in a different order.
  If our understanding of cosmology or general relativity ever fundamentally changed, it's the date of the observation that's going to actually be relevant. If your audience *is* a bunch of scientists, they're going to recognize this...
26. Re:The Crab Nebula wasn't born in 1054 AD by mazarin5 · 2009-02-23 17:55 · Score: 4, Interesting
  
  This is especially so when your audience is a bunch of scholars, scientists, and enthusiasts that are in the know and recognize glaring mistakes like this.
  Or, rather, people who are already damn well aware of this fact. If somebody took the time to point this out in an astrophysics journal, I would assume that they were either being paid by the word, or an exceptionally patronizing person.
  
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27. Re:The Crab Nebula wasn't born in 1054 AD by ceoyoyo · 2009-02-23 18:24 · Score: 1
  
  Don't forget to add in the correction for the universe expanding in that time, and any corrections required for the relative motion between us and the nebula and....
  Or you could just quit being pedantic and realize that the standard practice of referring to astronomical events happening when we observe them is not only justified by physics but is also the simplest way that makes sense.
28. Re:The Crab Nebula wasn't born in 1054 AD by mysticgoat · 2009-02-23 18:25 · Score: 1
  
  This means the birth of the Crab Nebula was in the year 5446 BC. Mankind witnessed it 6,500 years later.
  Actually what this means is that those who think the logic in parent post is valid need to bone up on relativity and light cones. Relative to the Earth, and therefore the majority of correspondents on Slashdot, the event happened in 1054 AD. Probably by coincidence, it also happened when the Earth-Moon double planet was at its aphelion. (And yes, the sinusoidal path of the Earth about the Sun due to the Moon's influence is significant when looking for accurate aphelion and perihelion points. Learned that while researching my book.)
29. Re:The Crab Nebula wasn't born in 1054 AD by mysticgoat · 2009-02-23 18:33 · Score: 1
  
  The time of an event is dependent on the moment when the event enters the light cone of the observer. So 1054 AD is the correct time of the supernova wrt Earth. We can infer that the event occurred at some other time in a different frame of reference but that is not directly observable. Just as we cannot know anything about any events that might be occurring on the opposite side of an event horizon.
30. Re:The Crab Nebula wasn't born in 1054 AD by Opyros · 2009-02-23 18:50 · Score: 1
  
  Maybe not.At least, the Bad Astronomer has argued in the past that Cyberax's point really is valid.
31. Re:The Crab Nebula wasn't born in 1054 AD by Colonel+Korn · 2009-02-23 18:55 · Score: 1
  
  That's because it's CORRECT. There's no such thing as 'absolute time'.
  1054AD _was_ the time of birth of the Crab Nebula from _our_ point of view.
  I'm amused that this was modded Funny. You know that this is what a relativistic physicist will tell you, right?
  
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32. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-23 18:57 · Score: 1, Informative
  
  RTFA, the only place the sentence quoted above is used is in the slashdot summary. The article correctly uses the words "witnessed" and "just 48 years later saw the birth of..."
33. Re:The Crab Nebula wasn't born in 1054 AD by Hal_Porter · 2009-02-23 19:11 · Score: 1
  
  Is that the sound the pendant made as it swung back and forth in the classic Edward Allen Pooh story "The Pendant and the Pit?"
  
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34. Re:The Crab Nebula wasn't born in 1054 AD by jnnnnn · 2009-02-23 19:19 · Score: 1
  
  I resent the implication that we share a point of view.
  1054 AD in your time or mine?
35. Re:The Crab Nebula wasn't born in 1054 AD by TapeCutter · 2009-02-23 19:20 · Score: 1
  
  Nice argument but.... Observing the CMBR I can deduce I am at the 'center of the universe' (big-bang's ground-zero). Another observer 10 billion light years away would observe the same thing and is therefore also at the 'center of the universe'.
  
  ie: The big-bang only accounts for the observable universe, it does not account the entire Universe unless you assume universe = Universe.
  
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36. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-23 20:16 · Score: 0
  
  Mod parent Insightful!
37. Re:The Crab Nebula wasn't born in 1054 AD by berend+botje · 2009-02-23 21:04 · Score: 1
  
  Not according to the photons that got emitted in the supernova. If you ask them, they will tell you that they got created far away and instantaneously smashed into a human eyeball over here.
  
  Yeah, physics is weird that way :-)
38. Re:The Crab Nebula wasn't born in 1054 AD by khallow · 2009-02-24 00:23 · Score: 1
  
  Yes. I was thinking the proper motion (the motion perpendicular to a vector between the Solar System and the object) also mattered, but it doesn't.
39. Re:The Crab Nebula wasn't born in 1054 AD by adamchou · 2009-02-24 00:23 · Score: 1
  
  of course explaining it is unnecessary. but proper verbiage would have been better. saying that they they witnessed the birth of the nebula in 1054 is much more correct than saying that the nebula was born in 1054.
40. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-24 00:26 · Score: 0
  
  Dunno about climate but the astrophysicists are pretty sure that many of the heavier elements come from extra solar events.
  See e.g.: http://www.nscl.msu.edu/science/nuclearastrophysics
41. Re:The Crab Nebula wasn't born in 1054 AD by adamchou · 2009-02-24 00:41 · Score: 1
  
  saying that the supernova occurred "simultaneous" to events in 5446 BC on Earth is the truly ridiculous claim on a cosmic scale.
  so if it didn't occur during 5446 BC on Earth, then when did it happen?
  seems like you are suggesting the date when an observer viewed the event is the correct date to record. based your other point that the birth date is wrong because of "another equally valid observor", i'm going to assume you mean someone not on earth (continuously traveling at an extremely high speed on earth isn't possible yet nor does it seem to have any point) otherwise we'd all be the "same" observers and you're argument doesn't make sense. so therefore, doesn't it follow that the date we view the event is effectively useless because there are various potential observers all viewing it at different dates. which one do you want to record? seems to me like specifying the date the event occurred is much more standard than the date an observer viewed the event.
42. Re:The Crab Nebula wasn't born in 1054 AD by Kagura · 2009-02-24 01:14 · Score: 2, Insightful
  
  Relativity of simultaneity
  
  There is a lot of material for the layman to easily understand. Enjoy the reading ;)
43. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-24 01:18 · Score: 0
  
  News stories on such phenomena invariably leave out this little fact, i.e., that which is witnessed by man in the sky usually happened thousands of years earlier than when he actually saw it. This makes it confusing for the average reader.
  I'd say the average reader doesn't even think about it. Anyone with a scientific understand of what is taking place know they are talking when the reached the earth(when the NO was formed).
  You are a pendant that can't miss an opportunity to reminded everyone else how smart you are.
44. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-24 01:40 · Score: 0
  
  This is very relevant as it's only the Crab Nebula here on Earth and from our point of view of it. Not only would it appear different (not crab like) from another vantage point, but any other observer is unlikely to use the same language or system of symbols we do. So the "Crab Nebula" could be said quite correctly to have been born at that time regardless of when the event which lead to that birth actually happened.
  Events here on Earth happen in the time frame relative (roughly) to here on Earth.
45. Re:The Crab Nebula wasn't born in 1054 AD by mcgrew · 2009-02-24 02:36 · Score: 1
  
  There's no such thing as 'absolute time'.
  Especially lunchtime.
  
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46. Re:The Crab Nebula wasn't born in 1054 AD by Cyberax · 2009-02-24 02:44 · Score: 1
  
  And do you take time dilation into account? Because the Solar System moves relative to the Crab Nebula.
  How about metric space expansion?
47. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-24 02:47 · Score: 0
  
  While those particular supernova may not have affected our climate (and I say "may not" because I haven't read any research that specifically examines the 5-10 period thereafter), prior supernovas *HAVE* caused ice ages here on earth.
  To say that our climate on earth is thus unaffected by what happens in outer space is being ignorant of existing research that shows otherwise.
  Maybe we'll need a supernova in 20-50 years just to cool the planet off after we've heated it up!
48. Re:The Crab Nebula wasn't born in 1054 AD by Hillgiant · 2009-02-24 02:49 · Score: 3, Insightful
  
  You know that this is what a relativistic physicist will tell you, right?
  Depends on how fast he's moving.
  
  --
  -
49. Re:The Crab Nebula wasn't born in 1054 AD by thePowerOfGrayskull · 2009-02-24 03:13 · Score: 2, Insightful
  
  However, this is being posted on an astro physics website.
  And as such, wouldn't it make sense that they assume certain knowledge (such as the fact that the impact of events here on Earth will occur on a timeline relative to the distance from the event) without needing to spell it out?
  Would you expect a math journal to explain how addition works before using it in a proof?
50. Re:The Crab Nebula wasn't born in 1054 AD by UNKN · 2009-02-24 03:32 · Score: 0
  
  Correct, assuming we are the only life forms in this corner of space. And if there are others out there they aren't experimenting on stars by causing them to go supernova.
51. Re:The Crab Nebula wasn't born in 1054 AD by dotancohen · 2009-02-24 04:14 · Score: 1
  
  This means the birth of the Crab Nebula was in the year 5446 BC. Mankind witnessed it 6,500 years later.
  As it was outside of our lightcone it cannot be said to have happened at that time for earthlings. Only when it enters our lightcone can the event be said to have happened. It's a tough concept, but time is _not_ the universal constant, the speed of light is.
  
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52. Re:The Crab Nebula wasn't born in 1054 AD by novakyu · 2009-02-24 04:23 · Score: 1
  
  Observing the CMBR I can deduce I am at the 'center of the universe' (big-bang's ground-zero).
  I'm not talking about where the origin of your coordinate system is. I'm talking about how fast your coordinate system is moving relative to any other inertial coordinate system (when people talk about inertial reference frame, they are far less interested in the origin of the coordinate system than they are about how fast it is moving relative to something else).
  Try getting yourself a picture of CMB. The largest feature in CMB is the anisotropy that comes from Doppler shift, that is, one side of CMB is blue-shifted, and the other is red-shifted. From this Doppler shift, one can actually calculate how fast Earth is moving relative to the inertial frame of universe.
  The expansion itself is unimportant as far as this reference frame business is concerened. The expansion happens *everywhere* (as you said, everything else moving away from everything else). The Big Bang is important from this point of view only in that it is the source of CMB, which gives a reference frame for comparison from *anywhere* *anytime* in the universe.
  The fluctuations in CMB that you hear about these days is nonuniformities you get *after* you remove these systematic anisotropies.
53. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-24 04:25 · Score: 0
  
  I'm trying to think of a good way to troll you, but that joke was so bad that I think you trolled yourself.
54. Re:The Crab Nebula wasn't born in 1054 AD by amoeba1911 · 2009-02-24 04:38 · Score: 1
  
  Why is this marked funny? It's no joke, it's absolutely true that time is relative to our point of view.
55. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-24 05:07 · Score: 0
  
  Someone has been teaching relativity really badly. A light cone splits events into those that could affect you and those who can't. It's certainly not telling you how to measure time. It's a cone shape on a time vs space plot. If you think that every point on the cone is at t=0, then it would be flat and not a cone.
56. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-24 05:20 · Score: 0
  
  Besides, the CO2 and other greenhouse gas emissions correlating pretty nicely with with the effects we're seeing
  No. No climate model based on CO2 has predicted the current failure of the temperature to go up, or the current downward trend.
  Hypothesises based on solar input regulated through trade winds and ocean currents however both predicted the cold spell and have a perfect track record.
57. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-24 05:49 · Score: 0
  
  They gave you writing, you moron. They gave you religion. They gave you CIVILIZATION. Without white colonialists you'd still be in your straw huts and climbing trees as just a bunch of nomadic tribes.
  br And don't forget. The Arabs are the ones that first started using African's as slaves en masse.
58. Re:The Crab Nebula wasn't born in 1054 AD by dwye · 2009-02-24 06:13 · Score: 1
  
  > our statement assumes that there is meaning to simultaneity, which is incorrect.
  There IS meaning for simultaneity, but only for each individual observer (observer here includes each sub-atomic particle, no ETs needed). There is also a meaning for observers sharing the same frame, i.e., at rest relative to each other.
  Thus, it is accurate to say that the supernova that formed the Crab Nebula occurred 6500 years earlier. In terms of the event that matters (the wave front ionizing atmospheric gasses), however, it is unimportant.
  Therefore, both sides of this should shut up and live with it. Actually, they will now turn on me, moderating all my posts as redundant trolls, but them's the breaks.
59. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-24 06:29 · Score: 0
  
  During the supernova explosion gammay rays have been shot @ 99.999% of the light speed. Gamma ray include also atoms of matter (those found into the ice) and they travel faster than light speed due relativity. At that speed mass increases and space reduces. It's incredible but matter has arrived before than light!!
60. Re:The Crab Nebula wasn't born in 1054 AD by mysticgoat · 2009-02-24 06:35 · Score: 1
  
  An event does not come into existence until its sequalae enter the light cone of the observer. Think about it.
  We can indeed infer that in another frame of reference, which is to say another universe than the one we inhabit, the event happened at a different time, but we should always remember that this is a fiction. It is sometimes a convenient shorthand to say that we are seeing back into the past when we look at a distant galaxy, but that phrasing uses older assumptions about the Universe that the theory of relativity has demonstrated to be wrong.
  Try not to confuse centrifugal force with reality. The reality is inertia, centrifugal force is a convenient fiction sometimes, but it is a fiction. Same goes with the concept of "fossil light": a convenient fiction, sometimes, but if it is confused with reality, the resultant model is too broad and very bogus.
  In fact, try not to confuse physics with reality. With the Copenhagen convention, a large number of physicists came to accept that physics is only good for building models, some of which approximate reality in useful ways. But physics itself is not the reality; it is only one model after another. All the way down; all the way up.
61. Re:The Crab Nebula wasn't born in 1054 AD by Hordeking · 2009-02-24 06:39 · Score: 1
  
  Try: 1054 A.D. which is when man observed the birth of the Crab Nebula
  One thing I'm curious about. Does this mean that we admit freely that extra-solar events affect the climate of this planet? Anyone have a slide rule handy and some star charts or galactic weather maps? Can we calculate probable effect on current climate conditions from extra-solar events?
  I thought that was a foregone conclusion.
  
  --
  Disclaimer: The opinions and actions of the US Gov't are in no way representative of those held by this author or its ci
62. Re:The Crab Nebula wasn't born in 1054 AD by Rich0 · 2009-02-24 06:39 · Score: 1
  
  Uh, relative to any frame of reference nothing travels faster than light in a vacuum. I could see some kind of refraction slowing the light down, but relativistic effects do not slow down light relative to any frame of reference - only matter.
  Now, it is entirely possible that from the frame of reference of the cosmic ray particles that travelled from the Crab Nebula to here that the trip took less time than would be predicted by a speed-of-light limit. However, at no point would such a particle observe light rays being passed or anything like that. From their frame of reference light is still flying past them at c.
  Also - gamma rays are composed entirely of photons. You're probably thinking of cosmic rays, which are often particulate.
  Yup - nothing I just wrote makes sense. That's relativity for you... I can make the trip from here to Andromeda in 15 minutes, and never exceed the speed of light by anybody's measure at any point along the way. If I made it a round trip I'd see it as taking 30 minutes and if mankind is still around it would be millions of years later when I arrive. From your own point of view you can travel arbitrarily fast (though light still will seem like it is whizzing by you), but an outside observer would just see you getting closer and closer to c.
  It just isn't possible for a piece of matter to overtake a photon in free space. The best you can do is refraction, and that is because the photons are interacting with matter which slows them down. If for some reason cosmic rays showed up before photons then it has something to do with the interstellar medium or some cloud of matter encountered along the way. It could not be a relativistic effect.
63. Re:The Crab Nebula wasn't born in 1054 AD by Rich0 · 2009-02-24 06:44 · Score: 1
  
  Point of view is contentious, after all, our point of view should take into account the knowledge of the time taken for the photons to reach us.
  From whose point of view? :)
  The photons? They didn't sense time pass at all the whole time.
  The center of the Crab Nebula? That is either a neutron star or a black hole (too lazy to look it up). That means that either fairly little time has passed, or no time has passed.
  The beauty of relativity is that it is convenient to say that an event happens once you see that it happens. Sure, you have to be smart enough to realize that not everybody else sees it that way, but what's the point in arguing over frames of references? I'm the only one with a privileged one... :)
64. Re:The Crab Nebula wasn't born in 1054 AD by adamchou · 2009-02-24 07:08 · Score: 1
  
  No, but you would not expect them to incorrectly refer to addition as substraction
65. Re:The Crab Nebula wasn't born in 1054 AD by SchmellsAngel · 2009-02-24 08:37 · Score: 1
  
  Ordinarily I hate spelling trolls, but hot damn, "You are a pendant..." is funny on so many levels. Especially in the context of a Hey Smarty Pants post.
  
  --
  We must repeat.
66. Re:The Crab Nebula wasn't born in 1054 AD by TapeCutter · 2009-02-24 10:10 · Score: 1
  
  "Big Bang is important from this point of view only in that it is the source of CMB, which gives a reference frame for comparison from *anywhere* *anytime* in the universe."
  
  Just as you are (incorectly) assuming things about me and what I have or haven't seen and understood, you are also assuming the CMB is a reference frame that is the same for everyone inside it, I think that assumption is wrong. Neither of us has any evidence other than what we observe from our own (vitually identical) reference frame. If I can add super-luminar expansion to the big-bang to make it fit the observations what's stopping me from saying it could have been lopsided exansion?
  
  As I said I think you have a good argument, I just don't buy it.
  
  --
  And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
67. Re:The Crab Nebula wasn't born in 1054 AD by novakyu · 2009-02-24 13:36 · Score: 1
  
  If I can add super-luminar expansion to the big-bang to make it fit the observations what's stopping me from saying it could have been lopsided exansion?
  Because the theory that describes the expansion, including the inflation era [1], specifically assumes a homogeneous, isotropic universe, as verified by CMB [2]. That's what's stopping you from saying that it could have been a lopsided expansion. There is no theory to support it, except by twisting existing observation to fit someone's ill-conceived idea.
  Remember the real power of any theory is not in the power of explanation ("God did it" is a perfectly good explanation for a lot of people), it's in the power of prediction. What I describing is the currently-accepted standard theory of the universe, and it has proven its worth by predicting a few astronomical phenomena before they were actually observed.
  And, according to the current, standard theory of the universe (a lot can go wrong with this theory the closer you get to the Big Bang and the smaller you get, where quantum mechanics and general relativity somehow have to merge; but in the macroscopic scale, we have no evidence that this tested and proven theory might be wrong), CMB is one thing that every observer in the universe—even in the parts of the universe that is not observable from our insignificant vintage point—will see, and compare whether they are moving with respect to the CMB, like we are, or not (as one might, at the "center of the universe").
  Notes
  [1] Which is specifically necessary to explain CMB, which shows that regions of space that are farther apart than the lifetime of universe are somehow causally connected, which means they had to be closer together in the past and some superluminal expansion drove them farther away than any light could reach it in time.
  [2] Which shows an isotropic distribution of background photons, except for the systematic anisotropy that arises from the Doppler shift and quantum fluctuation which was responsible for forming galaxies and stars.
68. Re:The Crab Nebula wasn't born in 1054 AD by BlackLungPop · 2009-02-24 19:31 · Score: 1
  
  Depends on how fast he's moving.
  Not to him.
69. Re:The Crab Nebula wasn't born in 1054 AD by TapeCutter · 2009-02-24 19:47 · Score: 1
  
  "Remember the real power of any theory is not in the power of explanation ("God did it" is a perfectly good explanation for a lot of people), it's in the power of prediction. What I describing is the currently-accepted standard theory of the universe, and it has proven its worth by predicting a few astronomical phenomena before they were actually observed."
  
  Good point about predictions but you are "preaching to the choir" here. I knew of the quantum fluctuations (also backed up by super-computer simulations), and that WMAP had shown the universe to be 'flat'. I admit I pulled the lopsided idea out of my arse and that I also missed the implications that a flat universe has for a common frame of reference, ie: I'm now willing to put a deposit on the idea. :)
  
  --
  And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
70. Re:The Crab Nebula wasn't born in 1054 AD by ultranova · 2009-02-24 23:34 · Score: 1
  
  This means the birth of the Crab Nebula was in the year 5446 BC. Mankind witnessed it 6,500 years later.
  
  Since we're being pedantic, I'd like to ask: from who's point of view? Observers who move in relation to each other will not agree on when spatially separated events happened in relation to each other. There is an inertial frame where the birth of Crab Nebula indeed happened between the start and end of the year 1054 AD on some point of Earth's surface as recorded by the local populace.
  
  News stories on such phenomena invariably leave out this little fact, i.e., that which is witnessed by man in the sky usually happened thousands of years earlier than when he actually saw it. This makes it confusing for the average reader.
  
  The nova that gave birth to Crab Nebula is commonly referred as the nova of 1054 AD. You're far more likely to confuse people by insisting that it be called the nova of 5446 BC. Besides, like I pointed out above, your timing is questionable too.
  
  --
  Forget magic. Any technology distinguishable from divine power is insufficiently advanced.
71. Re:The Crab Nebula wasn't born in 1054 AD by Anonymous Coward · 2009-02-25 04:46 · Score: 0
  
  Sure, we can't know about an event until it enter our light cone, but that doesn't imply we should timestamp it at the time we saw it.
  For example, light travel time to the moon is about 1.25 seconds. If we send a pulse that bounces off the moon, are you saying that the "correct times wrt Earth" are
  pulse sent: t=0
  pulse bounced on Moon: t=2.5
  pulse received on Earth: t=2.5
  ?
  Sorry but that doesn't fly. We like it when speed = distance / time.
Supernovae Found In Ice Cores by MillionthMonkey · 2009-02-23 14:54 · Score: 4, Funny

Only a matter of time until they find an actual frozen supernova in the ice.
1. Re:Supernovae Found In Ice Cores by cryfreedomlove · 2009-02-23 14:58 · Score: 1
  
  Could we harness that puppy as a safe source of clean energy?
2. Re:Supernovae Found In Ice Cores by AnonGCB · 2009-02-23 14:59 · Score: 2, Funny
  
  Once we find it then how long until we can clone it, and make an island full of them?
  
  --
  http://CryoLANparty.com/ A lan I'm staff on!
3. Re:Supernovae Found In Ice Cores by FearForWings · 2009-02-23 15:24 · Score: 1
  
  No, but we may be able to use it to cancel out the world ending black hole caused by the LHC when it comes online.
  
  --
  I don't know about angles, but it's fear that gives men wings. -Max Payne
4. Re:Supernovae Found In Ice Cores by khallow · 2009-02-23 15:35 · Score: 1
  
  All the current radioactive material came from one or more supernovas, so I'd have to say "no".
5. Re:Supernovae Found In Ice Cores by indi0144 · 2009-02-23 16:30 · Score: 1
  
  So the plot of NG Evangelion REALLY did happened? Are you positive? They were Japanese scientist and all.. OMG! OMFG!
  *runs to the basement*
6. Re:Supernovae Found In Ice Cores by mcgrew · 2009-02-24 03:12 · Score: 1
  
  Only a matter of time until they find an actual frozen supernova in the ice.
  It's a 1972 Chevy with a 396 engine with six barrel carbs and headers, located at the Fortress of Solitude.
  
  --
  Free Martian Whores!
If you didn't read TFA by BlackusDiamondus · 2009-02-23 14:55 · Score: 1

...It seems the third spike (assuming I am reading the graph correctly) occurred around 1060-1080AD.

--
Shit happens and it's usually caused by assholes
Dies the Fire by marcushnk · 2009-02-23 15:01 · Score: 1

ha! am reading this book atm... http://en.wikipedia.org/wiki/Dies_the_Fire
Made me think for a moment :-P

--
"Consider how lucky you are that life has been good to you so far. Alternatively, if life hasn't been good to you so far
1. Re:Dies the Fire by AgentOJ · 2009-02-23 15:36 · Score: 1
  
  That entire series is excellent, but having read all of the books in the series that have been published up to this point makes the wait until next fall for a new hard! Be sure to read the other series that starts with Island in the Sea of Time by S.M. Stirling as it ties in with the event in Dies the Fire.
2. Re:Dies the Fire by Anonymous Coward · 2009-02-24 04:24 · Score: 0
  
  I tried really hard to like it but couldn't. The Wiccan stuff was just too annoying.
global warming. by timmarhy · 2009-02-23 15:03 · Score: 1

clearly this is a conspiracy by oil companies to prove global warming isn't man made.

--
If you mod me down, I will become more powerful than you can imagine....
1. Re:global warming. by Anonymous Coward · 2009-02-23 17:23 · Score: 0
  
  More likely it's a conspiracy by Al Gore to prove that the climate on Earth isn't determined by natural cycles alone.
Supernova are bad.... by Anonymous Coward · 2009-02-23 15:07 · Score: 0

Supernova causes extinction:
http://www.msnbc.msn.com/id/3900550/
Supernova leads to ice age during the bronze age:
http://personals.galaxyinternet.net/tunga/BronzeAge.pdf.
It would be interesting to see if they can extrapolate general weather patterns for the 50 years following these 2 (or 3) supernova. Maybe this will give us a definitive answer on whether or not they can impact our weather and by how much.
1. Re:Supernova are bad.... by DigitalWallaby · 2009-02-23 16:00 · Score: 1
  
  Wasn't it somewhere around the 1000's to 1200's when the little ice age occured?
2. Re:Supernova are bad.... by Muad'Dave · 2009-02-24 01:18 · Score: 1
  
  Wikipedia says that the little ice age started in 1250 at the earliest, and 1650 at the latest. If the supernova caused it, there was at least a 200 year lag. If you want another coincidence, the Medieval Warm Period peaked during the time of the supernova.
  Oddly, there's a quote in the Little Ice Age article from 200 years before the earliest accepted start date (very near the time of the supernova - did the gamma rays precede the visible light photons?) that supposedly predicts the coming cold. That sounds an awful lot like modern-day people claiming a particularly cold day/week/month is evidence against global warming.
  
  Among the earliest references to the coming climate change is an entry in the Anglo-Saxon Chronicles dated 1046: "And in this same year after the 2nd of February came the severe winter with frost and snow, and with all kinds of bad weather, so that there was no man alive who could remember so severe a winter as that, both through mortality of men and disease of cattle; both birds and fishes perished through the great cold and hunger.
  
  --
  Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
Point of View by ChinggisK · 2009-02-23 15:12 · Score: 5, Funny

Hmm... "birth of the Crab Nebula" or "death of the Great Crab Civilization"?

You decide.
1. Re:Point of View by MichaelSmith · 2009-02-23 15:20 · Score: 5, Funny
  
  Hmm... "birth of the Crab Nebula" or "death of the Great Crab Civilization"? You decide.
  Yet another thing for Dr Zoidberg to be neurotic about.
  
  --
  http://michaelsmith.id.au
2. Re:Point of View by russotto · 2009-02-23 15:25 · Score: 1
  
  Hmm... "birth of the Crab Nebula" or "death of the Great Crab Civilization"?
  On that note, it looks like the data doesn't go back far enough to provide any evidence for the scenario in Clarke's "The Star"
3. Re:Point of View by MichaelSmith · 2009-02-23 15:43 · Score: 1
  
  Hmm... "birth of the Crab Nebula" or "death of the Great Crab Civilization"?
  On that note, it looks like the data doesn't go back far enough to provide any evidence for the scenario in Clarke's "The Star"
  Well they have only gone down a hundred metres or so to get this data. I wouldn't be surprised if they could double that. Calibration may be an issue until other dates are measured for older volcanoes, etc.
  
  --
  http://michaelsmith.id.au
4. Re:Point of View by thatskinnyguy · 2009-02-23 15:51 · Score: 1
  
  Tastes like crab, talks like people... CRAB PEOPLE!
  
  --
  The game.
5. Re:Point of View by Locke2005 · 2009-02-23 15:53 · Score: 2, Funny
  
  I believe 1054 AD (minus 6000 light years of travel time) was the approximate date that the residents of what is now the Crab Nebula finally got their Large Hadron Collider working...
  
  --
  I've abandoned my search for truth; now I'm just looking for some useful delusions.
6. Re:Point of View by Adilor · 2009-02-23 16:08 · Score: 1
  
  Attack their weak points for massive damage?
7. Re:Point of View by thatskinnyguy · 2009-02-23 16:12 · Score: 1
  
  What weak points? Their body is made out of armor!
  
  --
  The game.
8. Re:Point of View by rwa2 · 2009-02-23 19:02 · Score: 1
  
  This is just a test
9. Re:Point of View by mcgrew · 2009-02-24 04:25 · Score: 1
  
  A supernova didn't kill the crabs, the Vogons ate them.
  
  --
  Free Martian Whores!
10. Re:Point of View by RockDoctor · 2009-02-25 04:36 · Score: 1
  
  Hmm... "birth of the Crab Nebula" or "death of the Great Crab Civilization"?
  The progenitor star was (opinions vary) between approximately 9 and 12 solar masses, and of spectral type A, O, or B. Using standard approximations, this gives a lifetime for the star on the main sequence of 20 to 40 million years.
  The most-recent 20-to-40 million years of this planet's history has seen mammals evolve into other mammals, bats develop sonar, whales stop paddling around near the shore and move into deep water, and various fructivore monkeys develop bipedalism and expand their brains. But the first 20-to-40 million years of this planet's history included ... well, lots of meteorites re-melting the planet's surface, and maybe a little bit of rainfall. Did life evolve? Well, it's not impossible, but most people think that it's pretty improbable - the oceans were still re-forming and being boiled off at irregular but frequent intervals by large impacts. A couple of hundred million years later and you're into a much more benign biogenesis environment, but that's 5 to ten times the time span that's available.
  Of course, this analysis assumes that the "Crab Civilisation" were actually in orbit around the Crab progenitor star. They could conceivably have been just "in the area" and got whacked by this upstart star unrelated to their planet's formation. Which would have been pretty upsetting, but could only have been significant during a short interval in the species' history. While they're still trying to understand plumbing and the economies of scale of cities, they're only barely civilised ; a couple of millennia later and they should understand astrophysics well enough to recognise the problem in their skies and develop a mitigation strategy.
  "Many deaths" != "species extinction"
  
  --
  Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Tale of Genji by Anonymous Coward · 2009-02-23 15:17 · Score: 0

The Japanese novel Tale of Genji was supposedly written between 1008 and 1021 A.D.
It's been decades since I've read it... I wonder if there's any reference in there to smog around Mt. Fuji?
A bit further west, the Battle of Hastings was fought in 1066 A.D.
how do they know? by Anonymous Coward · 2009-02-23 15:28 · Score: 1, Funny

How do they know that the spike wasn't cause by some Connecticut Yankee's magic, hmmm?
Model A/B by spitzak · 2009-02-23 15:43 · Score: 1

Look at the image in the article:
image
If these really are the supernovae, doesn't this mean that "model B" is right and "model A" is wrong?
1. Re:Model A/B by radtea · 2009-02-23 16:17 · Score: 3, Informative
  
  If these really are the supernovae, doesn't this mean that "model B" is right and "model A" is wrong?
  The two models look like extrema that bound the dates.
  More interestingly, the sharpness of the spikes indicate that the sealing of atmospheric gases in the ice happens very suddenly. If it did not we would expect to see much broader and probably asymmetrical peaks.
  This is consistent with, but does not absolutely prove, a rather prompt mechanism for such sealing, rather than the long lagtime process that is sometimes invoked to explain why temperatures always rise tens or hundreds of years before CO2 levels do in ice core data. It would be very peculiar, albeit not impossible, to have a process that sealed the ice tens or hundreds of years after it was laid down as snow, but did so on a timescale of a year or so.
  
  --
  Blasphemy is a human right. Blasphemophobia kills.
2. Re:Model A/B by spitzak · 2009-02-24 04:13 · Score: 1
  
  CO2 can rise later than the heat if it is something other than CO2 that is causing the heat in the first place, you stupid denialist. There is more than one possible cause of global heating.
  Of course you won't understand and will accuse me of being paid off by the global warming conspiracy. I have to tell you that damn check bounced.
Drill down deeper by Locke2005 · 2009-02-23 15:47 · Score: 2, Interesting

I want to know if there was a supernova around the year 0 that would have been visible from the middle east...

--
I've abandoned my search for truth; now I'm just looking for some useful delusions.
1. Re:Drill down deeper by Anonymous Coward · 2009-02-23 15:52 · Score: 0
  
  There was. His name was Jeebus.
2. Re:Drill down deeper by JoshuaZ · 2009-02-23 16:12 · Score: 1
  
  Yes. http://en.wikipedia.org/wiki/The_Star_(short_story)
3. Re:Drill down deeper by Abcd1234 · 2009-02-24 06:37 · Score: 1
  
  If there had been, I suspect more than a couple wise men would've spotted it and thus there would be historical records. Yet, funny enough, no one's been able to identify such an event. Interesting, that...
4. Re:Drill down deeper by Anonymous Coward · 2009-02-24 07:52 · Score: 0
  
  You mean this?
5. Re:Drill down deeper by Anonymous Coward · 2009-02-24 11:37 · Score: 0
  
  Try back-dating astrology instead. Around 3 AD or so uou'll see some really funky retrograde orbit with (IIRC) Jupiter passing back and forth in front of Leo. Some other stuff, too. Can't remember the details.
Your Sig Is Fucked by Anonymous Coward · 2009-02-23 16:18 · Score: 0

your sig is truncated. try checking it out after you save a new one. that is all.
1054 A.D. by w0mprat · 2009-02-23 16:32 · Score: 1

The Crab system civilization turns on it's first Large Hadron Collider......

--
After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
1. Re:1054 A.D. by zipherx · 2009-02-23 20:48 · Score: 1
  
  Outch
Don't be so grandiose by Anonymous Coward · 2009-02-23 16:33 · Score: 0

If they find a nova in the ice, it may very well be a pretty darn good nova. But a super nova? Unlikely.
Betelgeuse by Big_Oh · 2009-02-23 17:19 · Score: 1

The crab nebula is 6500 light years away. The SN1006 event was 7200 light years away. The Betelgeuse supernova could appear to earthlings at any moment, and it's only 640 light years away.
1. Re:Betelgeuse by Datamonstar · 2009-02-24 00:09 · Score: 1
  
  I actually happen to be from the vicinity of Betelgeuse.
  
  --
  The eternal struggle of good vs. evil begins within one's self.
2. Re:Betelgeuse by mcgrew · 2009-02-24 03:45 · Score: 1
  
  The Betelgeuse supernova could appear to earthlings at any moment
  That's not a supernova, it's a Pan Galactic Gargle Blaster.
  
  --
  Free Martian Whores!
But there was no ice in the 1500's by __aawavt7683 · 2009-02-23 17:45 · Score: 1

Forgive me for the attention-seeking headline, but I've read very interesting things about Antarctica and its ice sheets.
Primarily, there were maps made in the 1500's that closely resemble an ice-free Antarctica. They document mountains we've detected in the 1900's by sonar, and reflect the Antarctic coastline closely.
If these maps are correct, and there was no ice in the 1500's... how were these ice cores found?
If the ice cores were found, and they date back to 1000 AD, how were these maps made with knowledge of Antarctica having no ice?
I'm very curious. One good article I found is here:
http://www.diegocuoghi.it/Piri_Reis/PiriReis_Hoye-Lunde.htm
Quite plausibly, it seems that the maps are, in fact, not maps of Antarctica. I wonder how that affects the arguments given... thoughts?
1. Re:But there was no ice in the 1500's by Anonymous Coward · 2009-02-23 18:04 · Score: 1, Interesting
  
  This was a central piece of evidence in Charles Hapgood's theory of crustal displacement. That theory has been pretty well debunked, the evidence that works in favor of continental drift works against crustal displacement. Similarly, the ice cores from Antartica are datable both by depth and by debris and gasses trapped inside.
  Of the Piri Reis map itself, it has some innaccuracies, and seems to have been cobbled together from other maps, but it does have a level of accuracy concerning the New World that one wouldn't expect in a 1500s map. The most likely explanation, assuming the map is not simply a hoax or put together in error, is that certain bits were copied from vastly older maps.
2. Re:But there was no ice in the 1500's by Entropy2016 · 2009-02-23 18:22 · Score: 4, Informative
  
  You're citing an 1980 article from "Aramco World Magazine" to introduce a bunk story on par with lost-city-of-atlantis myths. It's not even a peer reviewed journal. It's a magazine. You're giving these Piri Reis maps much more credit than they deserve. You say they
  
  closely resemble an ice-free Antarctica
  but from what I just read the maps didn't even have a waterway between Antarctica and South America. An ice free antarctica should have a *huge* friggin' waterway there.
  
  If these maps are correct, and there was no ice in the 1500's... how were these ice cores found?
  They aren't correct. See above.
  We have ice cores that we know go back more than 400,000 years. Give the guys who date these cores some credit. To me this iceless-antarctica idea just looks like a retired old historian/cartographer pushing a crackpot hypothesis. Yes, Antarctica wasn't always covered in ice, but that was millions of years ago.
3. Re:But there was no ice in the 1500's by imsabbel · 2009-02-23 19:46 · Score: 1
  
  There are maps from the 1500s that show california as an island.
  Seriously, is there a dumbass around to belive _anything_?
  do you even imagine how much it would have needed to snow in antarctica to build up the amount of ice there is now in only 5 centuries?
  
  --
  HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
4. Re:But there was no ice in the 1500's by TapeCutter · 2009-02-23 20:19 · Score: 1
  
  "If these maps are correct, and there was no ice in the 1500's... how were these ice cores found?"
  
  Excellent question, perhaps you could use an encyclopedia to find out more about these so called "ice cores".
  
  --
  And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
5. Re:But there was no ice in the 1500's by nicklott · 2009-02-23 20:53 · Score: 1
  
  They couldn't make ships that would routinely survive the antarctic sea until about 1750. How could they be be maps of antarctica in 1500?
6. Re:But there was no ice in the 1500's by khallow · 2009-02-24 00:32 · Score: 1
  
  The hypothesis is that Antarctica was ice free in 1500 and that someone mapped it, but we have 400,000 year old ice and a huge pile of ice overall that couldn't have been dumped in five centuries. So the hypothesis is wrong.
Re: In AD 2101 war was beginning by Anonymous Coward · 2009-02-23 20:19 · Score: 0

We get transmission, main screen turn on.
Re:parent is troll by TheTurtlesMoves · 2009-02-23 20:37 · Score: 2, Insightful

Typical response, from a religo nut job.

Debate is good, and everyone is permitted to have there opinion and ideas, more so when there is perhaps new data.

Why should we not discuss them? Being denied to speak anything against the consensus is what church and queen have done for centuries to keep everyone inline. It not science when you must agree with consensus or get silenced.

--
The Grey Goo disaster happened 3 billion years ago. This rock is covered in self replicating machines!
Mod parent insightful pls by assert(0) · 2009-02-23 21:43 · Score: 1

There's nothing particularly funny about the above correct statement.
I really can't believe people are having such a hard time grasping the consequences of "no absolute time."

--
(founded 95,000,000 yrs ago, very space opera)
Even more relevant to the debate... by mangu · 2009-02-23 22:08 · Score: 1

I think one important fact here is that scientists can measure the effect on the atmosphere of an event that happened a thousand years ago. Would it be reasonable to assume that they couldn't measure the effects of what's happening right now?
Yes, the sun variations influence climate. But human emission of gases into the atmosphere also influence climate, and scientists have means to determine the amount of influence due to each effect.
Snow crystal structure? by mangu · 2009-02-23 22:22 · Score: 2, Insightful

It would be very peculiar, albeit not impossible, to have a process that sealed the ice tens or hundreds of years after it was laid down as snow, but did so on a timescale of a year or so.
Why peculiar? That's exactly what I would expect. As snow gets piled higher, there will come a point when the weight from the accumulated snow is more than the strength of snow crystals can support. At the crystals get crushed, the structure will change from a porous mass of snow crystals to solid ice with some bubbles of gas.
This shift from snow to ice will happen quickly, because as a snow crystal breaks the weight it supported will shift to nearby crystals, increasing the stress on them. It could well be that the shift from porous to solid ice happens in a short period of time and, depending on average amount of snowfall, this could take tens of years of accumulated snow to happen.
1. Re:Snow crystal structure? by radtea · 2009-02-24 02:24 · Score: 1
  
  Why peculiar? That's exactly what I would expect.
  Why would you expect that ice and snow would happen to be in the range of strength/weight/accumulation parameters that would be required for this process to routinely take place due to a single year's accumulation of snow after a few decades or centuries of nothing much happening?
  That combination of timescales--nothing much happening for decades or centuries, then closure in a single year--bounds the acceptable parameters from both sides, which means that it would be a little surprising if they just happened to fall into that range. This is pretty much the textbook definition of "peculiar".
  Again, I am NOT saying this is impossible (although a big shout-out to the AC above who says I should be modded down because I'm a "deniallistalator" or whatever it's called) but I am saying that it strikes me that only a narrow range of physical parameters would happen to cause such sharp peaks after such a long time, and this sort of fine-tuning is the sort of thing that bothers physicists. It does happen: consider the famous result that the constants of nature are tuned such that toast almost always lands butter-side-down. This could be such a case.
  One of the nice things about data like these is that they ought to give us some information about what the parameters actually are, and therefore contribute to our understanding of whether CO2 leads or lags atmospheric temperature changes at the poles.
  
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2. Re:Snow crystal structure? by mangu · 2009-02-24 02:53 · Score: 1
  
  That combination of timescales--nothing much happening for decades or centuries, then closure in a single year--bounds the acceptable parameters from both sides, which means that it would be a little surprising if they just happened to fall into that range. This is pretty much the textbook definition of "peculiar".
  Take an old building. Its structure gradually weakens by the effect of time. Suddenly it collapses. Do you find it peculiar that a building that existed for a hundred years falls down in a matter of seconds? Or would you think it would be more likely that the first floor would gradually decrease in height over the years?
  The reason an old building falls suddenly is that, as the concrete or bricks weaken over time, there will be one point when the material breaks. Let's say a column buckles under the strain. Suddenly all the weight that was supported by that column must be supported by the neighboring columns. As the whole building is weakened by aging, it's very likely that the remaining columns will not be strong enough to take the increased strain, so the whole building falls down at once.
  Now replace the bricks with snowflakes. The whole snow mass is supported by the individual flakes, whose arms resemble microscopic columns and beams. There will be one point down there where the weight of the accumulated snow will be in the limit that individual snowflakes will support. Below that there is a solid mass of ice, with included bubbles. Above that, a porous mass of snowflakes where gas will diffuse from the atmosphere. Right in the middle, a region where snowflakes break down and entrap the diffused gas into the bubbles.
3. Re:Snow crystal structure? by radtea · 2009-02-24 03:38 · Score: 1
  
  Take an old building.
  Plausiblity for the win! That's a nice example. My counter-example would be the kind of old wooden farm building that I see a lot of, that really does slump slowly to the ground in exactly they way you say buildings don't. I used to wonder at these structures when I was growing up: old barns and outbuildings that would be in a state of almost complete collapse for years, but would never actually fall down. They just eased themselves slowly to the ground as their wooden structure deformed. Even a single structural member actually snapping wouldn't be enough to load the rest of the building to cause it to fall.
  This is the point to stop arguing analogies and actually and do some science by modelling the process of ice-pore collapse and seeing if it conforms more to your concrete-snaps analogy or my wood-deforms analogy. On a small scale I can see where you're coming from: the image of a single ice crystal snapping suddenly is clear, and the process of cascading collapse makes a certain amount of sense given the right parameters. On a larger scale, snow is notably flexible, and even ice is a lot less like concrete than you might think.
  Surely there must be some data out there on this stuff?
  
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  Blasphemy is a human right. Blasphemophobia kills.
Learn to Swim by shadowofwind · 2009-02-24 01:00 · Score: 1

There are maps from the 1500s that show california as an island.
Those are maps from the FUTURE, when the ice caps have melted and Los Angeles is Arizona Bay.
1. Re:Learn to Swim by layingMantis · 2009-02-26 12:17 · Score: 1
  
  cuz it's a bullshit three ring circus sideshow of freaks, here in those hopeless fucking hole we call LA. The only way to fix it is to flush it all away.
Re:parent is troll by mcgrew · 2009-02-24 03:39 · Score: 1

Typical response, from a religo nut job.
I saw no mention of religion at all, what are you talking about there? As to the rest of your comment, I agree.

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Re:parent is troll by TheTurtlesMoves · 2009-02-24 04:07 · Score: 1

Religion does not have to be about God. But even less so a fanatics response. In the past is was the religious folk who said this sort of thing. Note that I do not equate religion to god.

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The Grey Goo disaster happened 3 billion years ago. This rock is covered in self replicating machines!
Interesting, but.... by Kaptain+Kruton · 2009-02-24 07:16 · Score: 1

I think they have a somewhat interesting theory, but this data hardly proves anything. They have 3 spikes and only have 2 known known supernovas. They do not know the source of the third spike; they only have guesses. While their explanation seems plausible, I am not going to place a lot of faith in a theory that only has working evidence 2/3 of the time and the researchers must use unscientific guesses 1/3 of the time to maintain their theories.
Oh nonsense by unassimilatible · 2009-02-24 15:27 · Score: 0, Flamebait

Actually what this means is that those who think the logic in parent post is valid need to bone up on relativity and light cones.

This did not happen in 1054. I am well-aware of relativity smartass, and that has nothing to do with the simple historical fact that it happened 6,500 years before mankind experienced it.

Point out a different way of looking at things, get a nerd syntax error.

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