Mayan Calender
First of all, the Mayan calender is measured from 11 August 3114 BC which is when they thought their gods created the world. So, 2012 only has significance if you believe that the start date of their calender also has significance.
Do you believe that the Mayan gods created the world on 11 August 3114 BC? If you don't believe that, their calender doesn't have much relevance to you.
The Mayans also refer to dates well into our future and there is no evidence at all that they thought of this end of the 13th cycle of their long calender as an apocalypse. It would probably be a date of celebration for them. Mesoamerican Long Count calendar - 2012 and the long count
As astronomers they were good for their time, particularly given that they had no contact with astronomers in the rest of the world and independently discovered the Saros cycle of eclipses. However they were no better at astronomy than other ancient civilizations who studied astronomy without use of telescopes. Perhaps they are most noted for their fondness for extremely long time scales in their calenders. There is no evidence at all of any astronomical knowledge beyond what we are capable of today.
Most of this panic is due to the 2012 movie. The science and archaeology in the movie is far fetched with many mistakes. It has about as much scientific, astronomical, and archaeological accuracy as an Indian Jones movie.
Astronomer's predictions
The only prediction actually made by astronomers is that it will be a winter solstice (shortest day of the year in the Northern Hemisphere) - which happens every year.
The sun does pass through the galactic plane from time to time - the last time this happened was 3 million years ago, and it's due to happen again 30 or 40 million years from now.
Galactic Plane - 2012
Will Earth cross the galactic equator in 2012?
Milky Way - Sun's Location and Neighbourhood
Also if anything we are safest from radiation when we are in the region of the galactic plane - because the dust clouds in the plane of our galaxy help shield us from any galactic radiation there might be.
I think the people who write about an alignment and deadly radiation from the black hole are getting mixed up with ideas about Quasars and Active galactic nuclei
Our galaxy has a quiet nucleus. So its nucleus isn't a radiation hazard for us.
In galaxies that do have active galactic nuclei, the powerful jets are along the rotation axis of the black hole, which is perpendicular to the plane of the galaxy. In these galaxies the plane of the galaxy is the safest place to be, as it is far from the jet, and shielded from any radiation by the dust clouds.
So - what they say is just totally mixed up from an astronomical point of view. Hard to say if it was made up to weave a good story - or could be they are people who aren't particularly familiar with astronomy and science, who genuinely just misunderstood what the scientists and astronomers say. This stuff can be confusing to read for a non astronomer at times.
There is no planet approaching the Earth (never mind professional astronomers, even amateur astronomers with decent telescopes would have noticed anything like that years ago). Neutrinos do change type on the journey from sun to earth but as all the types of neutrino interact so weakly with matter that most pass through the entire Earth without noticing it, this isn't a threat either, and they have been doing this for billions of years.
Winter Solstice December 21 / 2012
Just one thing of astronomical significance happens this December 21. It is a winter solstice, the shortest day of the year. As it happens there is also a rough alignment of the sun, Earth and the center of the galaxy on this date as well. This all happens every year, and there is nothing special about this year in that respect.
So - you can celebrate the winter solstice - or wait for Christmas and celebrate it then if you prefer - or take part in whatever winter solstice celebration you have in your culture wherever you live.
Links
These website might be useful:
NASA - Beyond 2012: Why the World Won't End
Maya Calendars Actually Predict That Life Goes On
(includes youtube video by Nasa scientist)
Mayan doomsday 'misunderstanding'
No apocalypse is coming — Another Mayan calendar has been found
Planetary Alignments - 2012 hoax
See also this short video by a JPL Nasa Scientist
Another Nasa video by Jim Morrison from Nasa
See my longer answers here on Yahoo Answers as well - with some more links you might find useful
Is there going to be a planetary alignment in 2012?
When are all the 2012 Natural Disasters going to start?
Astronomical disasters that could happen on any date with only a few hours of notice
Though there are no astronomical predictions of this type for 2012, there are a few general threats from space that do concern astronomers. Some of those could happen on any day with only a few hours of warning.
They can't be predicted, except as probabilities. You can't say for sure that they won't happen on any particular date, indeed, even today.
The Mayans couldn't predict them any more than we can. So doesn't make sense to link them to the Mayan calender. But if you are concerned about civilization destroying events, these are things that from an astronomical point of view you can be genuinely concerned about.
The chance of any of these happening is low though, and they are no more likely to happen this year than on any other year in the past thousands of years of human civilization.
Civilization threatening disasters are so rare that the chance is high that the next one won't happen for another million years or so. There are many other more immediate things that are likely to affect us before then.
So - no need to lose any sleep over them :).
However, it is worth while studying them to see if we can do anything to prevent them in the remote chance that any do happen. The effects are major if they do happen, even if the probability of any of them is low. Some of the less devastating events are more common and we can actually do something about them too.
Solar storms
Solar storms are perhaps top of the list here because they are quite common. We get many of those, and as he says in the video, generally you hardly notice them though a few satellites have been damaged. But from time to time you get really big solar storms such as the Solar storm of 1859 . It didn't do much damage then, but of course now our world is much more reliant on electricity than the world of 1859.
A storm as big as that could cause serious damage to electricity transmission grid. It could happen almost any time, most likely perhaps during solar maximum.
Though not civilization threatening, a huge solar storm could mean tough times for many - just having the electricity cut off for many homes - and lead to a possibly trillions of dollars cost for repairs of the transmission grid and other equipment.
Hardening our transmission lines against this risk has been estimated to cost billions of dollars. See for instance the NY Times article:. Not Ready for a ‘Solar Sandy’
Large meteorites
Then there are impacts from meteorites. These again could happen without warning. The larger ones happen every million years or so. So- the chances are that it will be hundreds of thousands of years before the next one - but could happen today of course.
The Space Guard project is devoted to mapping out the NEOs (Near Earth Objects). Most are now mapped but there are enough gaps so that it is still possible that a large NEO could approach the Earth with only a few hours of warning.
As time goes on more and more will be mapped. Eventually once they are all mapped we should have plenty of warning of any risk.
The worse the impact the less likely, for comet and meteorite impacts. So - though it is very likely that there will be a significant impact in say the next thousand years, it is almost certain to be just a city sized impact region. Large enough to be devastating and to be worth a lot of effort to prevent or mitigate it, but not likely to be civilization destroying particularly.
You expect hundreds of the smaller city threatening size impacts for every one of the larger civilization threatening impacts.
There is a table near the bottom of this page - as you can see the civilization destroying events happen every 80 million years or so on average. While H-bomb size events happen every 5,000 years or so.
NEO Frequently Asked Questions (FAQ)
The main focus at present is on detecting all the NEOs with potential to impact the Earth in the future. There is also some work on methods for deflecting them. The consensus is that it would be possible to deflect a NEO, and easier to do that if you had a long term prediction, so detecting the NEOs and determining their orbits is the first priority.
Comets from the Oort cloud
These are harder to deal with. The Oort cloud is a reservoir of comets beyond Pluto. From time to time the comets get deflected towards the sun and may approach Earth.
In this case we do have at least a few months of warning - most large comets are detected many months before they reach the inner solar system.
The chance of one of these hitting the Earth is lower than for a NEO - because you have only the one pass by of the Earth, and they aren't that common. Maybe every few tens of millions of years a comet large enough to be threatening could impact the Earth.
But again you can't rule them out, though at least you do have a few months warning if you do spot one. It is worth researching into how you might possibly deflect such a comet if you did spot one. Also to think of how you might evacuate parts of the world. Since you would have at least a few months notice, evacuation is something you could consider, if you could do nothing about the impact.
Nearby Supernova
If one of the really close nearby stars went supernova - that would be pretty devastating for life on Earth. However they would have to be very close,
The larger stars that lead to Type II supernovae are easy to spot from a distance away, so we know about all the ones close to Earth that could go supernova. These stars go supernova after they go Red Giant first, and then run out of fuel. One example is Betelgeuse. They are all far enough away to be no threat to Earth.
The Type Ia supernovae are more of a risk as they arise from dimmer white dwarf stars, which are very common and not so well studied. In these superonovae, a white dwarf star in mutual orbit with another star gradually accumulates material from its companion, until it suddenly gets too much and it collapses in a supernova.,
Still even the Type Ia supernovae have to be pretty close, within 10 parsecs of the sun, to be a major threat. The nearest supernova candidate is 150 light years away (46 parsecs away), and is expected to go supernova a few million years in the future. Supernova Milky Way Candidates
No supernova of either type has been observed in our Galaxy yet by telescope. The last supernova observation was by Tycho Brahe in 1572 supernova, which coincidentally occurred just a few years before the invention of the telescope with the first patent for a telescope applied for in 1608 see History of the telescope.
Gamma Ray Bursts
These are little understood and rare in individual galaxies - though they are so bright that we see them from galaxies billions of light years away. They may have caused extinctions in the past on the Earth. See Gamma-ray burst
These are even harder to protect against - the radiation is strong and focused, so if by chance it did impact on the Earth it would be hard to protect against it. The source could be far away in our galaxy, and since the radiation arrives at the speed of light, there might be no warning at all.
It is hard to know what you could do about a nearby supernova or gamma ray burst with current technology, especially a gamma ray burst as you might have no warning at all. In the distant future maybe you could protect against them with a system of tiny satellites with mirrors and nanotech to configure the mirrors to instantly open and rotate to deflect the radiation away from Earth - a form of Utility fog.
The probabilities of any of these happening in the near future are low though, as for the other astronomical threat, and have probably happened to the Earth many times in the past, and of course, no link with 2012. See 2012: Fear No Supernova
One of these events will surely happen eventually
On the time scale of hundreds of millions of years the probability is high that one or other of these things will happen eventually. Hopefully by then we will have the knowledge and technology to be able to do something about it.
Other things
There are a few other potential threats, including primordial microscopic black holes floating free in space - no evidence for them, but some cosmologists think there is a remote possibility that they might exist.
Since Earth has survived for 4.5 billion years, and there are no signs of any other planets, moons or asteroids "blinking out" like that, then there must be very low chance that it will end in this way.
Actual "End of the world" predicted by astronomy
There is one astronomical disaster that will definitely happen, which we can't do anything about, and unlikely to be able to avert except with major mega-structure type technology.
Eventually the sun will go red giant, a few billion years in the future. The Earth might or might not survive, but will certainly get very hot.
Also, its oceans boil dry long before the sun reaches that stage. This happens only a billion years from now
Any intelligent beings left on the Earth at all similar to ourselves in biology will need to leave it before then. Mars may briefly become habitable at that point, then perhaps the moons of Jupiter, or we (or our distant relatives) might be a totally space faring race by then with dwellings throughout the asteroid belt and Oort cloud.
Future of the Earth - Oceans boil dry
However, we have a good few hundred million years before we need to worry about that and think about how to deal with it.
Or rather our descendents or maybe descendents of other species around today will have to face that problem eventually, but have a few hundred million years before it happens.
First of all, the Mayan calender is measured from 11 August 3114 BC which is when they thought their gods created the world. So, 2012 only has significance if you believe that the start date of their calender also has significance.
Do you believe that the Mayan gods created the world on 11 August 3114 BC? If you don't believe that, their calender doesn't have much relevance to you.
The Mayans also refer to dates well into our future and there is no evidence at all that they thought of this end of the 13th cycle of their long calender as an apocalypse. It would probably be a date of celebration for them. Mesoamerican Long Count calendar - 2012 and the long count
As astronomers they were good for their time, particularly given that they had no contact with astronomers in the rest of the world and independently discovered the Saros cycle of eclipses. However they were no better at astronomy than other ancient civilizations who studied astronomy without use of telescopes. Perhaps they are most noted for their fondness for extremely long time scales in their calenders. There is no evidence at all of any astronomical knowledge beyond what we are capable of today.
Most of this panic is due to the 2012 movie. The science and archaeology in the movie is far fetched with many mistakes. It has about as much scientific, astronomical, and archaeological accuracy as an Indian Jones movie.
Astronomer's predictions
The only prediction actually made by astronomers is that it will be a winter solstice (shortest day of the year in the Northern Hemisphere) - which happens every year.
The sun does pass through the galactic plane from time to time - the last time this happened was 3 million years ago, and it's due to happen again 30 or 40 million years from now.
Galactic Plane - 2012
Will Earth cross the galactic equator in 2012?
Milky Way - Sun's Location and Neighbourhood
Also if anything we are safest from radiation when we are in the region of the galactic plane - because the dust clouds in the plane of our galaxy help shield us from any galactic radiation there might be.
I think the people who write about an alignment and deadly radiation from the black hole are getting mixed up with ideas about Quasars and Active galactic nuclei
Our galaxy has a quiet nucleus. So its nucleus isn't a radiation hazard for us.
In galaxies that do have active galactic nuclei, the powerful jets are along the rotation axis of the black hole, which is perpendicular to the plane of the galaxy. In these galaxies the plane of the galaxy is the safest place to be, as it is far from the jet, and shielded from any radiation by the dust clouds.
So - what they say is just totally mixed up from an astronomical point of view. Hard to say if it was made up to weave a good story - or could be they are people who aren't particularly familiar with astronomy and science, who genuinely just misunderstood what the scientists and astronomers say. This stuff can be confusing to read for a non astronomer at times.
There is no planet approaching the Earth (never mind professional astronomers, even amateur astronomers with decent telescopes would have noticed anything like that years ago). Neutrinos do change type on the journey from sun to earth but as all the types of neutrino interact so weakly with matter that most pass through the entire Earth without noticing it, this isn't a threat either, and they have been doing this for billions of years.
Winter Solstice December 21 / 2012
Just one thing of astronomical significance happens this December 21. It is a winter solstice, the shortest day of the year. As it happens there is also a rough alignment of the sun, Earth and the center of the galaxy on this date as well. This all happens every year, and there is nothing special about this year in that respect.
So - you can celebrate the winter solstice - or wait for Christmas and celebrate it then if you prefer - or take part in whatever winter solstice celebration you have in your culture wherever you live.
Links
These website might be useful:
NASA - Beyond 2012: Why the World Won't End
Maya Calendars Actually Predict That Life Goes On
(includes youtube video by Nasa scientist)
Mayan doomsday 'misunderstanding'
No apocalypse is coming — Another Mayan calendar has been found
Planetary Alignments - 2012 hoax
See also this short video by a JPL Nasa Scientist
Another Nasa video by Jim Morrison from Nasa
See my longer answers here on Yahoo Answers as well - with some more links you might find useful
Is there going to be a planetary alignment in 2012?
When are all the 2012 Natural Disasters going to start?
Astronomical disasters that could happen on any date with only a few hours of notice
Though there are no astronomical predictions of this type for 2012, there are a few general threats from space that do concern astronomers. Some of those could happen on any day with only a few hours of warning.
They can't be predicted, except as probabilities. You can't say for sure that they won't happen on any particular date, indeed, even today.
The Mayans couldn't predict them any more than we can. So doesn't make sense to link them to the Mayan calender. But if you are concerned about civilization destroying events, these are things that from an astronomical point of view you can be genuinely concerned about.
The chance of any of these happening is low though, and they are no more likely to happen this year than on any other year in the past thousands of years of human civilization.
Civilization threatening disasters are so rare that the chance is high that the next one won't happen for another million years or so. There are many other more immediate things that are likely to affect us before then.
So - no need to lose any sleep over them :).
However, it is worth while studying them to see if we can do anything to prevent them in the remote chance that any do happen. The effects are major if they do happen, even if the probability of any of them is low. Some of the less devastating events are more common and we can actually do something about them too.
Solar storms
Solar storms are perhaps top of the list here because they are quite common. We get many of those, and as he says in the video, generally you hardly notice them though a few satellites have been damaged. But from time to time you get really big solar storms such as the Solar storm of 1859 . It didn't do much damage then, but of course now our world is much more reliant on electricity than the world of 1859.
A storm as big as that could cause serious damage to electricity transmission grid. It could happen almost any time, most likely perhaps during solar maximum.
Though not civilization threatening, a huge solar storm could mean tough times for many - just having the electricity cut off for many homes - and lead to a possibly trillions of dollars cost for repairs of the transmission grid and other equipment.
Hardening our transmission lines against this risk has been estimated to cost billions of dollars. See for instance the NY Times article:. Not Ready for a ‘Solar Sandy’
Large meteorites
Then there are impacts from meteorites. These again could happen without warning. The larger ones happen every million years or so. So- the chances are that it will be hundreds of thousands of years before the next one - but could happen today of course.
The Space Guard project is devoted to mapping out the NEOs (Near Earth Objects). Most are now mapped but there are enough gaps so that it is still possible that a large NEO could approach the Earth with only a few hours of warning.
As time goes on more and more will be mapped. Eventually once they are all mapped we should have plenty of warning of any risk.
The worse the impact the less likely, for comet and meteorite impacts. So - though it is very likely that there will be a significant impact in say the next thousand years, it is almost certain to be just a city sized impact region. Large enough to be devastating and to be worth a lot of effort to prevent or mitigate it, but not likely to be civilization destroying particularly.
You expect hundreds of the smaller city threatening size impacts for every one of the larger civilization threatening impacts.
There is a table near the bottom of this page - as you can see the civilization destroying events happen every 80 million years or so on average. While H-bomb size events happen every 5,000 years or so.
NEO Frequently Asked Questions (FAQ)
The main focus at present is on detecting all the NEOs with potential to impact the Earth in the future. There is also some work on methods for deflecting them. The consensus is that it would be possible to deflect a NEO, and easier to do that if you had a long term prediction, so detecting the NEOs and determining their orbits is the first priority.
Comets from the Oort cloud
These are harder to deal with. The Oort cloud is a reservoir of comets beyond Pluto. From time to time the comets get deflected towards the sun and may approach Earth.
In this case we do have at least a few months of warning - most large comets are detected many months before they reach the inner solar system.
The chance of one of these hitting the Earth is lower than for a NEO - because you have only the one pass by of the Earth, and they aren't that common. Maybe every few tens of millions of years a comet large enough to be threatening could impact the Earth.
But again you can't rule them out, though at least you do have a few months warning if you do spot one. It is worth researching into how you might possibly deflect such a comet if you did spot one. Also to think of how you might evacuate parts of the world. Since you would have at least a few months notice, evacuation is something you could consider, if you could do nothing about the impact.
Nearby Supernova
If one of the really close nearby stars went supernova - that would be pretty devastating for life on Earth. However they would have to be very close,
The larger stars that lead to Type II supernovae are easy to spot from a distance away, so we know about all the ones close to Earth that could go supernova. These stars go supernova after they go Red Giant first, and then run out of fuel. One example is Betelgeuse. They are all far enough away to be no threat to Earth.
The Type Ia supernovae are more of a risk as they arise from dimmer white dwarf stars, which are very common and not so well studied. In these superonovae, a white dwarf star in mutual orbit with another star gradually accumulates material from its companion, until it suddenly gets too much and it collapses in a supernova.,
Still even the Type Ia supernovae have to be pretty close, within 10 parsecs of the sun, to be a major threat. The nearest supernova candidate is 150 light years away (46 parsecs away), and is expected to go supernova a few million years in the future. Supernova Milky Way Candidates
No supernova of either type has been observed in our Galaxy yet by telescope. The last supernova observation was by Tycho Brahe in 1572 supernova, which coincidentally occurred just a few years before the invention of the telescope with the first patent for a telescope applied for in 1608 see History of the telescope.
Gamma Ray Bursts
These are little understood and rare in individual galaxies - though they are so bright that we see them from galaxies billions of light years away. They may have caused extinctions in the past on the Earth. See Gamma-ray burst
These are even harder to protect against - the radiation is strong and focused, so if by chance it did impact on the Earth it would be hard to protect against it. The source could be far away in our galaxy, and since the radiation arrives at the speed of light, there might be no warning at all.
It is hard to know what you could do about a nearby supernova or gamma ray burst with current technology, especially a gamma ray burst as you might have no warning at all. In the distant future maybe you could protect against them with a system of tiny satellites with mirrors and nanotech to configure the mirrors to instantly open and rotate to deflect the radiation away from Earth - a form of Utility fog.
The probabilities of any of these happening in the near future are low though, as for the other astronomical threat, and have probably happened to the Earth many times in the past, and of course, no link with 2012. See 2012: Fear No Supernova
One of these events will surely happen eventually
On the time scale of hundreds of millions of years the probability is high that one or other of these things will happen eventually. Hopefully by then we will have the knowledge and technology to be able to do something about it.
Other things
There are a few other potential threats, including primordial microscopic black holes floating free in space - no evidence for them, but some cosmologists think there is a remote possibility that they might exist.
Since Earth has survived for 4.5 billion years, and there are no signs of any other planets, moons or asteroids "blinking out" like that, then there must be very low chance that it will end in this way.
Actual "End of the world" predicted by astronomy
There is one astronomical disaster that will definitely happen, which we can't do anything about, and unlikely to be able to avert except with major mega-structure type technology.
Eventually the sun will go red giant, a few billion years in the future. The Earth might or might not survive, but will certainly get very hot.
Also, its oceans boil dry long before the sun reaches that stage. This happens only a billion years from now
Any intelligent beings left on the Earth at all similar to ourselves in biology will need to leave it before then. Mars may briefly become habitable at that point, then perhaps the moons of Jupiter, or we (or our distant relatives) might be a totally space faring race by then with dwellings throughout the asteroid belt and Oort cloud.
Future of the Earth - Oceans boil dry
However, we have a good few hundred million years before we need to worry about that and think about how to deal with it.
Or rather our descendents or maybe descendents of other species around today will have to face that problem eventually, but have a few hundred million years before it happens.
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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