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Comet May Have Missed Earth By a Few hundred Kilometers
First time accepted submitter afree87 writes "A re-analysis of historical observations at a Mexican observatory suggests Earth narrowly avoided an extinction event just over a hundred years ago. On August 12th and 13th 1883, an astronomer at a small observatory in Zacatecas in Mexico made an extraordinary observation, some 450 objects, each surrounded by a kind of mist, passing across the face of the Sun. This month, Hector Manterola at the National Autonomous University of Mexico suggests these were fragments of a comet. 'If they had collided with Earth we would have had 3275 Tunguska events in two days, probably an extinction event.'"
3275 of em. That's a heck of a shotgun blast.
May have missed ? I'm fairly certain it definitely missed.
And likely just a *little* too early to blame Nikola Tesla... if we would have had any conspiracy theorists left.
How Slashdotters approach all scientific articles:
1. Abounding skepticism.
2. Criticism of scientist's findings and methods used.
3. Explanation of failed logic.
4. Loss of all wonder and awe and appreciation at whatever findings remain.
5 Cynicism and dejection at failure of science.
6. Continued existence of misery and woe and greater skepticism.
My tongue is jammed up against my cheek; otherwise, I'd say more. God bless.
As a scientist, don't author your paper with the font set to Comic Sans.
Sig this!
It would probably have been calamitous but extinction level, maybe not. I mean most of those would probably have landed in the ocean anyway, with maybe a thousand or so dropping on land. The Tunguska event didn't raise too much atmospheric dust or cause much occlusion, and at around 10 megatons might have released in total ten gigatons or so, which is what, twice the total world nuclear arsenal except without fallout.
Apocalypse territory? Certainly. Extinction? Probably not.
>best not to think of these things
What an idiotic thing to say. Yes, there are people who think about these things and they try to come up with practical solutions. Yeah, let's not think about this. Someone might come up with a way of diverting certain death some day.
>keeping a comet secret in this day and age.
Good luck with that.
There are thousands of amateur astronomers across just the US alone and we've got the internet and everyone would know within hours of discovery anyway.
--
BMO
While we know that in practice actual asteroid and comet strikes on Earth are very rare, this sort of thing helps illustrate how we need to do a good job tracking the larger threats and preparing to deflect them if necessary. The good news is that the WISE mission http://en.wikipedia.org/wiki/Wide-field_Infrared_Survey_Explorer has successfully tracked most of the large asteroids that have near-Earth orbits and none of them are threats in the immediate future. There are however other dangers. For example, comets that are no longer outgassing could potentially have very elliptical orbits that would not be detected by WISE. Also, there may be smaller asteroids that WISE has not detected that could make a life pretty unpleasant in a more narrow area even if they don't lead to an extinction event. An asteroid that was around a thousand feet across (300 meters) could devastate a city and could easily escape detection from WISE. Moreover, there are some real worst case scenarios. If such an asteroid landed in either Pakistan or India for example they might think that the other had launched a nuclear weapon at them.
In general, we aren't doing enough to deal with potential existential risks. At this point, we don't know if the Great Filter is in front or behind us. http://en.wikipedia.org/wiki/Great_Filter. The basic idea of the Great Filter is that the easiest explanation of the Fermi Paradox is that there's some set of events that make life unlikely to reach the interstellar level. That could be behind us, if for example life arising is unlikely or multicellular life arising is unlikely. But at least some filtration has to be in front of us. It seems that natural events (like asteroid strikes) are not common enough to be the entire filter. But there are other potential filtration events. Learning more about these issues not only helps preserve humanity it also helps get insight into why we seem to be alone. Unfortunately, funding for these sorts of things is tiny. The WISE mission for example was only $320 million and was used not just for the asteroid work but a lot of other good astronomy for objects both inside our solar system and more distant objects. This is a tiny cost compared to what is spent on non-science issues, and is particularly tiny when one considers it as being paid for almost exclusively by a single country.
My work here is dung.
Let's go burn down the observatory so this will never happen again!
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
"I was almost hit by a car yesterday"
"Statistically, there's no way you would still be alive if you were hit by a car every single day. What a lair!"
ASCII stupid question, get a stupid ANSI
In fact, if it exists, shouldn't it be easy to find as it will likely have an orbit that repeatedly intersects earth's orbit?
Only if its in the same inclination as the earth relative to the sun. Classic orbital mechanics mistake... just because two things are up there (lets say, ISS and HST) doesn't mean they'll ever come really close to each other.
Gravitational slingshot might mean the orbit has been permanently changed. On a long enough scale, from the perspective of small enough objects, there are no non-chaotic orbits. There are Lagrangian points and there is no reason for long term stability there (even the most stable ones can get swept clean by some orbiting "whatever" that passes near enough or thru the L point).
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Yes, I would, so I could go on TV and say "See? I've been telling you we need to spend more money on space science! But no...! Now we're all screwed because you all wanted another tax cut for your bosses!"
http://alternatives.rzero.com/
I'm waiting to hear from the fiscal conservatives who want to cancel the space program and asteroid-hunting programs because the Federal Government shouldn't be spending taxpayer money on such useless endeavors.
Most self-proclaimed "conservatives" in Congress usually insist that they want a socialized space program with a central government authority which has exclusive rights for access to space... private companies are neither needed nor wanted except in a support role where cost-plus contracts are handed out to the lobbyist who has schmoozed them with the best campaign contributions. Of course all of this is good because it helps out the local congressional district with billions of dollars of "stimulus money" to help keep local bureaucrats employed.
The "liberal Democrat" answer: privatized spaceflight from companies competing for fixed-price contracts open to competition and demonstrating that they are able to actually accomplish the task before they are awarded any money.
It was former senators William Proxmire and Walter Mondale who were most in favor of cancelling the "space program" in earlier eras. Guess which political party they belonged to, if you don't already know?
No, I don't get space politics either, just don't let your head get warped out on this issue.
I'll be blunt: I'm not buying it. I give details on my blog, but I think there are too many holes in the idea. For one thing, comets aren't that small; passing within a few thousand klicks of one would put us inside the debris field. We'd have seen vast numbers of meteors. For another, no one else saw it? At all? Comets can be visible during broad daylight - I've seen one myself - yet there's not a single other observation of a comet that close from any other person on Earth. So I am very, very, very skeptical.
*** Phil Plait, aka The Bad Astronomer http://www.badastronomy.com
"No, I don't get space politics either"
It's actually very simple now. The primary competency of military-industrial complex is extracting government funding by managing the procurement and political process. This is why you have say NorthroBoeingheed winning all sorts of contracts to perform random technology and other services from the government.
In particular over the last 30 years, the MIC has split their facilities geographically for maximum political coverage, these days usually in the deep-'red' (and obviously not Red) districts of powerful Republican Congressmen, since they are the pro-military-spending ones. Space hardware is just an minor extension of this blob. The United Launch Alliance has a monopoly on launching NRO and DOD payloads and they charge lots and lots of money.
SpaceX and say Orbital Sciences have a prime competency in cost-effective rocket engineering and not government, and their facilities are concentrated in Los Angeles and Northern Virginia, and they have much less money. Northern Virginia is 'purple' and LA is 'blue'.
So that's why most Republicans are opposed to private-sector cost-effective NASA contracts, because in a fair technical and economic competition, SpaceX will massacre their political supporters in NorthroBoeingheed.