APOD: Asteroids Near Earth (2011 Oct 01)

Comments and questions about the APOD on the main view screen.
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Beyond
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Re: APOD: Asteroids Near Earth (2011 Oct 01)

Post by Beyond » Sun Oct 02, 2011 2:02 am

Uh-oh :!:
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rstevenson
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Re: APOD: Asteroids Near Earth (2011 Oct 01)

Post by rstevenson » Sun Oct 02, 2011 2:10 am

owlice wrote:There is no such thing as a "good beer" for an American commercial brew!
:D
My thought exactly. There's English style ale (perferably "Bitter") and there's German style beer (Pilsener and the like.) Each is made in the traditional manner, sold in a relatively small geographic range, and therefore each local brand has its own unique characteristics. All of the global-brand manufactured "byrs" (thanks Chris) are pallid imitations, best used for mouth wash or toilet bowl cleansing.

Rob

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Re: APOD: Asteroids Near Earth (2011 Oct 01)

Post by saturn2 » Sun Oct 02, 2011 3:05 am

Very well.
It aren´t 35,000 asteroids.
" Only" it are 19,500 asteroids near to Earth. :)

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Re: APOD: Asteroids Near Earth (2011 Oct 01)

Post by owlice » Sun Oct 02, 2011 3:23 am

rstevenson wrote:best used for mouth wash
Ugh, no! Then it might hit the taste buds!
rstevenson wrote:or toilet bowl cleansing
Some might opine that much of it is used in, though not necessarily for, that very activity (or leading to it), especially on Friday and Saturday nights in university towns...
A closed mouth gathers no foot.

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Re: APOD: Asteroids Near Earth (2011 Oct 01)

Post by Chris Peterson » Sun Oct 02, 2011 4:00 am

owlice wrote:There is no such thing as a "good beer" for an American commercial brew!
And yet, some of the best beers in the world are American. I'd even say the best, period. But not from the big commercial breweries, that's for sure.
Chris

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Re: APOD: Asteroids Near Earth (2011 Oct 01)

Post by mactavish » Sun Oct 02, 2011 4:14 am

Oh pity the innkeeper’s plight
When his customers, night after night,
Order only pale brew
And brown ale eschew —
For his dark is much worse than his lite.

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Beyond
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Re: APOD: Asteroids Near Earth (2011 Oct 01)

Post by Beyond » Sun Oct 02, 2011 4:30 pm

ah mactavish, ye have a wee bit of the Irish poet in ye, aye?
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Re: APOD: Asteroids Near Earth (2011 Oct 01)

Post by zbvhs » Sun Oct 02, 2011 6:29 pm

I saw a program on television (History or Science Channel) about a site in the eastern Sahara that is littered with some sort of glassy nodules much like fulgurites produced by lightning strikes. Since lightning strikes are exceedingly rare in the eastern Sahara, some other event must have created the high temperatures needed to fuse desert sand to glass.

Apparently simulations have shown that an incoming body doesn't have actually strike the surface to cause damage. Under certain conditions the body can vaporize completely at high altitude and the resulting hypersonic shock wave can continue on to the surface. The impact of the shock wave produces high over-pressures on the ground or, in the case of the eastern Sahara event, temperatures high enough to fuse sand to glass.

An event of this sort was presented as an explanation for the damage seen after the Tunguska event. High over-pressures felled trees in a radial pattern over a large area. The effects of high over-temperatures, however, were mitigated somewhat by snow cover on the ground and the extreme cold of the Siberian winter. According to this explanation, very little - if any - of the incoming body would have reached Earth's surface, which explains the apparent lack of a visible crater on the ground.
Virgil H. Soule

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Chris Peterson
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Re: APOD: Asteroids Near Earth (2011 Oct 01)

Post by Chris Peterson » Sun Oct 02, 2011 6:53 pm

zbvhs wrote:I saw a program on television (History or Science Channel) about a site in the eastern Sahara that is littered with some sort of glassy nodules much like fulgurites produced by lightning strikes. Since lightning strikes are exceedingly rare in the eastern Sahara, some other event must have created the high temperatures needed to fuse desert sand to glass.
Sounds like you are talking about Libyan desert glass, which is generally associated with a meteoritic event, although whether an actual impact or an air burst remains unresolved.
Chris

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Re: APOD: Asteroids Near Earth (2011 Oct 01)

Post by iamlucky13 » Mon Oct 03, 2011 5:26 am

NoelC wrote:This strikes me as the kind of thing that would be better expressed as a video, with a 3D "flyover" showing where all these asteroids are, and maybe even animated to show their motion.

'Course that might scare the hell out of folks (me included).

-Noel
It absolutely would!

Here's an old version. Hopefully we'll see this updated over time.

http://www.arm.ac.uk/neos/anim.html

It loaded very slowly for me, so give it time. It's worth it. Note that this is known asteroids (who's orbits have been determined, hence why there's way fewer than 20,000 shown in the inner solar system.

Note also a lot of near earth asteroids (red) have highly elliptical orbits. They can at any moment cross the earth's orbit and therefore appear to be contradict the suggestion that the earth has cleared it's orbit, but they do not share the orbit (different eccentricity), which is part of the distinction regarding Pluto.

@mactavish - Brilliant, I love it.


Anybody who doesn't think the US has good beers needs to spend some time on the west coast. I spent a month earlier this year in the UK, which while far from the beer capital in the world, left me very disappointed after some of the comparisons others had made in favor of the UK beer scene over that of the US.
owlice wrote:There is no such thing as a "good beer" for an American commercial brew!
Surprisingly, the big brewers are catching on. Blue Moon, for example, is a downright decent Belgian wheat brewed by Coors. However, Coors can not afford to let themselves be identified with it, so they created a subsidiary "Blue Moon Brewing Company" for marketing purposes.

Not to mention, some of the bigger craft breweries are quite successful commercial scale operations. Craft Brewers Alliance (formed by the merger of Widmer Brothers and Redhook) bottles $140 million per year worth of beer. 3 of the top 10 breweries in the US are "craft" brewers, even if you don't include Sam Adams in that category.
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Chris Peterson
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Re: APOD: Asteroids Near Earth (2011 Oct 01)

Post by Chris Peterson » Mon Oct 03, 2011 2:52 pm

iamlucky13 wrote:Anybody who doesn't think the US has good beers needs to spend some time on the west coast. I spent a month earlier this year in the UK, which while far from the beer capital in the world, left me very disappointed after some of the comparisons others had made in favor of the UK beer scene over that of the US.
Or Colorado! My experience is similar to yours- I've had some fine beers in the UK (especially some heather ales in Scotland, which I've never found anywhere else), but I've generally found that my favorite beers are American microbrews. A peculiarity in Europe is that many major brand beers are actually produced in multiple small breweries- sometimes with different recipes, even. For example, Guinness tastes quite different in different parts of Ireland, depending on the local brewery that makes it. You only see this in pubs, though, as the bottled product is (so far as I know) the same everywhere.
Surprisingly, the big brewers are catching on. Blue Moon, for example, is a downright decent Belgian wheat brewed by Coors...
The good (though seldom great) brews coming from the big commercial operations remind me very much of the situation in Europe, and to a lesser extent Asia, where the big breweries typically produce much better beers than their American counterparts. That is, the main output of Heineken, Carlsberg, and other large breweries is quite good- better in general than we see from Coors or Budweiser. Brews like Blue Moon show that large operations can produce high quality beers. Nothing to match fine craft beers, but that is hardly surprising.
Chris

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