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Asteroid passing below some of our satellites on feb 15

Posted by: SANEAlex - Tue Jan 15, 2013 8:30 pm
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Asteroid passing below some of our satellites on feb 15 
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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Sat Feb 16, 2013 11:33 pm
:D On rare occasions people do cut themselves using Occam's razor :wink: :twisted:

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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Sun Feb 17, 2013 12:42 am
JamesG, with all due respect, I think there isn't really a lot to back up your theory that doesn't fall into the realm of "global conspiracy".

ESA said those events weren't related.
NASA said those events weren't related.
Both Roscosmos and the Russian Academy of Science said those events weren't related.
As did pretty much every Astronomer that got interviewed on Friday.

Oh and because of the distance between the two objects (due to the time difference between the events) orbital dynamics also say they can't be related, because they can't have been in the same/similar orbit. Why? Because since 2012 DA14 missed us by just a little bit, an object traveling many hours in front of it would have missed us by quite a lot more.

But if they weren't in the same/similar orbit, how are they related again?


But whatever actually is the case, I personally hope that this is the kind of wakeup call that we need to get our space program(s) to the level of ambition that they used to be a few decades ago...

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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Sun Feb 17, 2013 3:20 am
I think it falls more along the lines of what is the most convenient thing to say. It is technically true that DA14 did not fall on Russia. It can't be proven one way or another where the Russian Meteor originated, and its both reassuring to the public and the credibility of officials if they agree that it was just a "largest meteor in a century, that happened to enter the atmosphere at the same time that another asteroid wandered by. Look! a squirrel!"

As for the physics, not necessarily. It would depend on how big of a dispersion there was/is between the known DA14 object and any others. While we might have been "late" (or early depending on your perspective) for DA14, maybe not for a leading (or trailing, see San Francisco meteor) companion.

While it's just an abstract discussion for now, I think it might be kind of important, a clue that maybe our perception that the asteroids are solitary objects might be incorrect and that they may be more complex than we thought. Not just in their composition, but that they might be little systems of objects in their own right. This will have bearing on when we plan NEO "defense" and exploration/mining.


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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Sun Feb 17, 2013 11:52 am
From reading your arguments may I assume, that you did not follow any media coverage of 2012 DA14's approach?

2012 DA14 passed by the earth in a (roughly) South->North oriented motion. The essential aspect here is that it was/is NOT on the same (or similar) orbital plane as the Earth. I don't know anything about that San Francisco Meteor (just that apparently there was one), but the Russian Meteor hit us 16 hours! before the approach of 2012 DA14.

For an object in 2012 DA14's orbit, but traveling 16 hours in front of DA14, it is simply impossible to get caught by earths gravity well on (or before) February 15th, 2013. It would have passed close to Earth's orbit when the Earth was still a lot* farther away.

Have a look at this simulation of DA14's approach:
http://en.wikipedia.org/wiki/File:2012_DA14.ogg

Edit:
* a "lot" = ~1.7 million kilometers (or ~1.07 million miles)

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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Sun Feb 17, 2013 4:08 pm
No. I am quite aware of DA14's orbital path. In fact, my theory *requires* a high obliquity approach. I just haven't articulated it in detail because, I didn't think it necessary. It seemed to me to be pretty obvious...

Imagine if you will several million years ago the object we would call DA14 was either struck by another asteroid or made a very close approach inside the Roche Limit and got teased apart. This trauma gave pieces of the body slightly more momentum than it's feeble escape velocity and so they have been slowly inching away from each other until they were spread over as much as a quarter of an AU in diameter, all traveling in formation with the same orbit.

Fast forward to last week. Another intercept occurs. While the monkeys on Earth see the main body of DA14 and breath a sigh of relief that it is going to pass "behind" the planet, what they didn't see was that the lead edge of the debris field, including what would become the "Russian Meteor" (RM) got there first and the Earth ran them down 16 hrs before closest approach of the main object. RM just happens to be in the capture key-hole and gets slung into a parabolic orbit, perhaps even grazing the Earth's atmosphere high over the South Pacific and losing a lot of energy. It then slings wide up over the North pole and then arcs down into the atmosphere over Central Asia at about the time that DA14 has caught up and is making it's safe close passage. One (or more) of it's closer companions wasn't so fortunate and plunged into the Earth's atmosphere becoming the "SF meteor".

What should be a concern to us, if you open your mind to consider this scenario, is that the orbital solution required for an object to be captured is very narrow. Most of them would get flung out or otherwise have their orbits disturbed, but would not crash into the Earth. That we (ok I) know that at least two did hints that there were enough of a swarm of objects in DA14's little constellation that even when "shotgunned" several managed to get caught.


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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Mon Feb 18, 2013 1:52 pm
2012 DA14 didn't pass "behind" us (regarding our motion around the Sun), it passed us on the far side of the Sun, aka outside of Earth's orbit (sidenote: due to Earth's gravity it's orbit was changed enough so that what used to be an Apollo class asteroid is now an Aten class asteroid, meaning that its orbit is now mainly inside Earth's orbit).

Any of your hypothesized "swarm objects" traveling in front of 2012 DA14 therefore have no other chance than to pass Earth by a greater distance than 2012 DA14 itself. The same would of course be true for objects traveling behind 2012 DA14.

Just to be sure I'll repeat that I'm only talking about the Russian Meteor, since I have no information on the SF Meteor.

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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Mon Feb 18, 2013 3:10 pm
:roll: Okay. Believe whatever you want.


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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Mon Feb 18, 2013 11:14 pm
Sorry, "believe" isn't really part of my value system.

I just have a hard time accepting your arguments as facts:

"the most convenient thing to say" [that they weren't related] - sorry, not even an argument.

"millions of years ago" [something happened] - Ok, can't argue here, but you might as well go back to the formation of the solar system to construct your relation between any two random rocks near Earth's orbit...

a debris field "spread over as much as a quarter of an AU in diameter, all traveling in formation with the same orbit." - sorry, but that's not how my minuscule knowledge about orbital dynamics tells me that it works. Maybe for a debris field from a recent collision it can be "assumed" to be still "on the same orbit", but not for something millions of years ago. If something in an orbit with a period of about one year starts to slowly drift apart (for whatever reason: impact, etc.) and has time to do so for millions of years, you end up with the pieces on quite different orbits, because of the now different masses and velocities of the fragments.

I'm open for any evidence that the two events were related, but so far you only provided speculation as far as I can tell.

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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Tue Feb 19, 2013 2:10 am
You do understand what theory and hypothesis are right?

I am disinclined to continue discussing this topic with your belligerent condescending attitude. Good day.


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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Tue Feb 19, 2013 11:25 am
I want to apologize if I came across as "belligerent" and "condescending", that was not my intention. I guess it has to do with the fact that I get a bit "energetic" whenever I think someone is (intentionally or unintentionally) spreading FUD.

My comment about assuming that you did not follow any coverage of the events and had no clue about the trajectories was inappropriate and out of place. Sorry.

This comment triggered a change in your writing style, that I interpreted as personal attacks:
* " I just haven't articulated it in detail because, I didn't think it necessary. It seemed to me to be pretty obvious..."
* "... if you open your mind to consider this scenario..."
* rolling eyes and "Believe whatever you want."
(all three basically imply that you think I'm stupid...)


And it escalated from there as I responded. So once again I'm sorry.



Back to the topic, I found some interesting updates:
http://www.esa.int/Our_Activities/Opera ... assessment

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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Mon Feb 25, 2013 5:08 pm
I know the conversation has been a bit heated recently i did wonder if they were connected initially but as more and more data came in it seemed increasingly unlikely. Here are the lasted calculations it seems it is likely that it was an Apollo asteroid.

http://www.technologyreview.com/view/51 ... meteorite/

IMHO events like these just show how much we need to collect a lot more data to increase the understanding of the situation we are currently in. Mostly blind at the bottom of a gravity well is how i would put it in my more cynical pessimistic moments. But maybe this event may encourage the opening of at least one eye.

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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Tue Feb 26, 2013 4:44 am
Eh, I only hope someone with the time and resources is looking at alternative scenarios and trajectories instead of everyone just going, "yup, yup, yup."

Marcus-

Apology accepted. I'm sorry I got you annoyed. My comments were me being "funny", and my ire was directed toward the science establishment, not you in particular.

Remember, no one has a monopoly on the truth, not even those who create it for a living.


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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Tue Feb 26, 2013 7:02 am
Meteor expert Clark Chapman and former astronaut Rusty Schweickart urge U.S. military to re-initiate sharing of satellite detections of meteor impacts:

Russian Meteor Fallout: Military Satellite Data Should Be Shared.
by Leonard David, SPACE.com’s Space Insider Columnist
Date: 18 February 2013 Time: 09:03 AM ET
http://www.space.com/19846-russian-mete ... lites.html

From links in the article, the military formerly did share this information but the policy was changed in 2009. This is important because the satellites reportedly have the capability to detect meteors down to 1 meter wide and below. This would well have the capability to determine if close asteroid flybys result in increased meteor impacts.


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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Tue Feb 26, 2013 7:22 am
JamesG wrote:
Yeah, you sound like a lotto player. :wink:
The probability of two different objects on unrelated trajectories arriving at "near approach" with Earth at effectively the exact same time are infinitely smaller than the two being related and having arrived together.
Hopefully we don't get "confirmation" of this hypothesis by additional events.

That the meteor and asteroid were both large and got so close was what was so notable about them. That they both occurred within the same 24 hour period make them extraordinarily unlikely.

These scientists both came to highly unlikely probabilities for this to occur by chance alone:

A meteor and asteroid: 1 in 100 million odds.
By Meg Urry, Special to CNN
updated 8:16 PM EST, Mon February 18, 2013
http://www.cnn.com/2013/02/16/opinion/u ... index.html

Meteor over Russia causes shock waves that injure at least 950.
Posted by: Dr. Jeff Masters, 3:12 PM GMT on February 15, 2013.
Quote:
According to NASA (as posted on spaceweather.com), "the trajectory of the Russian meteorite was significantly different than the trajectory of the asteroid 2012 DA14, making it a completely unrelated object. Information is still being collected about the Russian meteorite and analysis is preliminary at this point. In videos of the meteor, it is seen to pass from left to right in front of the rising sun, which means it was traveling from north to south. Asteroid DA14's trajectory is in the opposite direction, from south to north." The odds of the largest meteor strike in 100 years occurring on the same day as the closest asteroid approach in 15 years are about 1 in 200 million, assuming these events are not correlated--truly a cosmic coincidence!
http://www.wunderground.com/blog/JeffMa ... rynum=2350



Bob Clark

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Single-stage-to-orbit was already shown possible 50 years ago with the Titan II first stage.
Contrary to popular belief, SSTO's in fact are actually easy. Just use the most efficient engines
and stages at the same time, and the result will automatically be SSTO.
Blog: http://exoscientist.blogspot.com


Last edited by RGClark on Tue Feb 26, 2013 11:43 am, edited 1 time in total.



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Post Re: Asteroid passing below some of our satellites on feb 15   Posted on: Tue Feb 26, 2013 7:41 am
JamesG wrote:
...
Fast forward to last week. Another intercept occurs. While the monkeys on Earth see the main body of DA14 and breath a sigh of relief that it is going to pass "behind" the planet, what they didn't see was that the lead edge of the debris field, including what would become the "Russian Meteor" (RM) got there first and the Earth ran them down 16 hrs before closest approach of the main object. RM just happens to be in the capture key-hole and gets slung into a parabolic orbit, perhaps even grazing the Earth's atmosphere high over the South Pacific and losing a lot of energy. It then slings wide up over the North pole and then arcs down into the atmosphere over Central Asia at about the time that DA14 has caught up and is making it's safe close passage. One (or more) of it's closer companions wasn't so fortunate and plunged into the Earth's atmosphere becoming the "SF meteor".


I like your "keyhole" hypothesis:

Close encounter of a useful kind.
Humans will ponder fate as an asteroid just misses them.
Nov 21st 2012 |From The World In 2013 print edition.
Quote:
The fly-by in 2013 will be a boon for several reasons, says Andrea Milani Comparetti, head of NeoDyS, a team at Italy’s University of Pisa that calculates asteroid trajectories. First, it will enable astronomers to calculate more precisely the slim odds that 2012 DA14 will smash into Earth the next time it comes close, in 2026. Data available today suggest a one-in-27,000 chance of a collision in 2026. More precise measurements will probably reveal a future impact to be even less likely. But if 2012 DA14 passes through a roughly 500-metre-wide “keyhole” strip of space that happens to be about 28,100km from Earth, gravity could tug its orbit just enough for it to hit the Earth 13 years later on February 13th, a Friday. In that event, a spacecraft would surely be scrambled to nudge the rock back into a harmless orbit.
http://www.economist.com/news/21566431- ... seful-kind



Bob Clark

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Single-stage-to-orbit was already shown possible 50 years ago with the Titan II first stage.
Contrary to popular belief, SSTO's in fact are actually easy. Just use the most efficient engines
and stages at the same time, and the result will automatically be SSTO.
Blog: http://exoscientist.blogspot.com


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