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Re: Coincidence of meteor strike and close asteroid approach at same time.
Posted:
Feb 28, 2013 2:43 PM
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On Feb 28, 11:38 am, Robert Clark <rgregorycl...@yahoo.com> wrote:
> On Feb 27, 1:33 pm, j...@specsol.spam.sux.com wrote:
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> > In sci.physics Robert Clark <rgregorycl...@yahoo.com> wrote:
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> > > That video I linked to previously and ones like it may also be able
> > > to address this question:
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> > > An Asteroid's Parting Shot.
> > > By Phil Plait
> > > Posted Tuesday, Feb. 19, 2013, at 8:00 AM
> > >http://www.slate.com/blogs/bad_astronomy/2013/02/19/near_earth_astero...
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> > > The video shows 2012 DA14 slowing moving through the frame, and
> > > meteors and artificial satellites streaking rapidly through the frame.
> > > Assuming we are able to distinguish the satellites, perhaps by
> > > knowing already their positions, perhaps we can determine if the
> > > number of meteors shown here are higher than normal.
> > > Better would be longer exposures that include at least the time
> > > period of the Russian meteor impact.
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> > > Bob Clark
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> > While people here have been speculating all sorts of nonsense, astronomers
> > from the University of Antioquia in Medellin, Colombia have figured out
> > where the Russian meteor came from and that it has no relationship to
> > the other close passing asteroid.
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> >http://www.space.com/19974-russian-meteor-explosion-origin-size.html
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> The Fireballs of February.
> Feb. 22, 2012
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> "They all hail from the asteroid belt?but not from a single location
> in the asteroid belt," he says. "There is no common source for these
> fireballs, which is puzzling."
> "This isn't the first time sky watchers have noticed odd fireballs in
> February. In fact, the "Fireballs of February" are a bit of a legend
> in meteor circles.
> "Brown explains: "Back in the 1960s and 70s, amateur astronomers
> noticed an increase in the number of bright, sound-producing deep-
> penetrating fireballs during the month of February. The numbers seemed
> significant, especially when you consider that there are few people
> outside at night in winter. Follow-up studies in the late 1980s
> suggested no big increase in the rate of February fireballs.
> Nevertheless, we've always wondered if something was going on."
> "Indeed, a 1990 study by astronomer Ian Holliday suggests that the
> 'February Fireballs' are real. He analyzed photographic records of
> about a thousand fireballs from the 1970s and 80s and found evidence
> for a fireball stream intersecting Earth's orbit in February. He also
> found signs of fireball streams in late summer and fall. The results
> are controversial, however. Even Halliday recognized some big
> statistical uncertainties in his results."
> ...http://science.nasa.gov/science-news/science-at-nasa/2012/22feb_febru...
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> Note this was from last year, not this year in regard to this
> February's unusual meteor and asteroid encounters. But what's key is
> the article notes this has been noticed in other February's.
> The article suggests greater number of fireballs in February. It also
> mentions they are typically slow, long-lasting, and penetrate deep in
> the atmosphere. I don't know about the slow part, but the long-lasting
> and deep penetration aspects could be due to larger meteors during
> February's.
> If there is an association with the 2012 DA14 asteroid, then since
> it has approximately a year long orbit, this could explain why the
> fireballs are seen frequently in February. Note it was discovered
> last year in February also during a close approach.
> Also notable as Steve Willner mentioned the two orbital crossings
> could result in rather close approaches on the second crossing as
> well:
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> On Feb 26, 1:56 pm, will...@cfa.harvard.edu (Steve Willner) wrote:
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> > > Does this mean there are two close approaches per orbit? It doesn't
> > > necessarily have to be since where the two orbits "cross" does not
> > > mean the two bodies have to be there at the same time.
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> > Yes, exactly. Typically one body will be far away when the other is
> > near a crossing point.
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> > > if they are close at one "crossing" point, they should be
> > > relatively close at the other.
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> > About half a day away at the next crossing point, given the period of
> > 366.24 days. That's about 400 Earth radii if I've done the
> > arithmetic right. The distance is cumulative, so a simple estimate
> > is that it will take another 366 years (365 orbits for the asteroid)
> > before there's another close approach. However, the recent Earth
> > encounter must have changed the orbit, so the simple estimate is
> > probably wrong. There are also likely to be non-gravitational
> > effects. This object is probably not one to worry about in the near
> > term, but this sort of rough estimate is no substitute for a proper
> > orbit calculation.
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> This could explain the observation of Halliday that there seems to be
> a statistical increase also in late Summer and Fall.
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> In any case, the Air Force needs to release its satellite detections
> of these fireballs. For one thing they might be able to detect the
> meteors before they have any appreciable interaction with the
> atmosphere. For large meteors, of oblong shape, the atmospheric
> interaction could alter their direction, thus giving a misleading
> interpretation of their original orbits.
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> For many people the Air Force not sharing all the technical means at
> its disposal led to the loss of the shuttle Columbia crew. It must not
> be said that its keeping its meteor detections capability secret led
> to the loss of an entire city.
>
> Bob Clark
Since when do mainstream oligarchs care about the rest of us?
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