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Normal Constellation of the Stars



 
 
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  #11  
Old December 24th 08, 01:47 AM posted to alt.astronomy
Saul Levy Saul Levy is offline
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First recorded activity by SpaceBanter: Jul 2006
Posts: 21,291
Default Normal Constellation of the Stars

You forgot to mention the CUSTOM-FILTERED OPTICS, BradBoi! lmfjao!

Saul Levy


On Tue, 23 Dec 2008 11:18:35 -0800 (PST), BradGuth
wrote:

Human contributed soot that's laced with our methane, freons, CO2, NOx
and increased atmospheric h2o is affecting the views of most
everything as seen from below 10 km.

Too bad there's still nothing of any public remote observatory
situated at our Selene/moon L1. You do realize why, don't you?

Imagine what a TRACE-II along with another 10 fold optical improvement
plus another 10 fold CCD pixel density/mm2 would have accomplished.
(that's only 100 fold better off than TRACE has had to offer as is).

By more than a decade ago, a good set of easily extended mirror optics
would have had our Selene/moon nailed at 0.1 m/pixel, along with
nearly unlimited UV and IR spectrum to boot.

~ BG

  #12  
Old December 24th 08, 06:45 AM posted to alt.astronomy
Timberwoof[_2_]
external usenet poster
 
Posts: 799
Default Normal Constellation of the Stars

In article ,
Saul Levy wrote:

On Tue, 23 Dec 2008 01:06:28 -0800, Timberwoof
wrote:

In article
,
wrote:

I wonder if anyone has noticed. In my area of Southern California
there are very few "stars," if any.
The normal constellations appear to be gone. Has anyone else noticed
this? If you have noticed,
why do you think that might be the case.


Two reasons, air pollution and light pollution. There are so many street
lights around for a hundred miles in every direction from LA that the
sky is brighter than the stars.

Light pollution is a serious problem for astronomers. They have
certainly noticed. In Silicon Valley, the James Lick Observatory on Mt.
Hamilton has convinced San Jose and other nearby cities to use
mercury-vapor street lamps because they emit light only in certain parts
of the visible spectrum. Astronomers are thus free to observe in the
"dark" parts of the spectrum.

If you want to see the grandeur of the Milky Way for yourself, then one
night take I-15 out into the desert. I-5 north is not as good because
the sky is hazier. Take any side road at least half a mile from the
freeway and any town lights. Then look up. Bring blankets and a thermos
with hot coffee.

Check your local PBS listings for Jack Horkheimer's "Star Hustler"
program. Each week he does a five-minute spiel about some special thing
happening in the night sky. It's a great introduction to amateur
astronomy; you don't even need a telescope.


Mercury vapor lights are a disaster for astronomy, woofie!


I misremembered. The mercury vapor lights were replaced...
http://mtham.ucolick.org/public/ligh...peration2.html

You mean sodium vapor.


But not with low-pressure sodium vapor lights. Those emit a
characteristic yellow light which the street lights of San Jose do not
have. They're pinkish.

http://ioannis.virtualcomposer2000.c...ope/amici.html
Interestingly, this article says that high-pressure sodium vapor lamps
are the leading cause of light pollution.

And Jack Horkheimer didn't tell that to you. He knows better.


No, actually, the tour guide at Lick Observatory told me and I can see
the lamps for myself any evening in Silicon Valley.

--
Timberwoof me at timberwoof dot com http://www.timberwoof.com
Most of the universe is extremely hostile to life as we know it. It seems
obvious that it was all designed by some creature that hates life... And here
you are, trying to attract its attention.
  #13  
Old December 24th 08, 12:35 PM posted to alt.astronomy
Saul Levy Saul Levy is offline
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First recorded activity by SpaceBanter: Jul 2006
Posts: 21,291
Default Normal Constellation of the Stars

Yes those are LOW-PRESSURE sodium vapor lamps, woofie.

I always thought they should look yellow, but they look pink to me
too. The eye (brain?) can lie!

Astronomers love them!

High-pressure sodium vapor lamps are very similar to mercury vapor
lamps in that they use a lot more of the spectrum for it's emissions.
Low-pressure mainly emits two spectral lines.

See: http://en.wikipedia.org/wiki/Sodium_vapor_lamp

and

http://ioannis.virtualcomposer2000.c...ope/amici.html
see the 1.4.x pictures.

It's the blue and UV emissions which astronomers hate.

Saul Levy


On Tue, 23 Dec 2008 22:45:25 -0800, Timberwoof
wrote:

In article ,
Saul Levy wrote:

On Tue, 23 Dec 2008 01:06:28 -0800, Timberwoof
wrote:


Mercury vapor lights are a disaster for astronomy, woofie!


I misremembered. The mercury vapor lights were replaced...
http://mtham.ucolick.org/public/ligh...peration2.html

You mean sodium vapor.


But not with low-pressure sodium vapor lights. Those emit a
characteristic yellow light which the street lights of San Jose do not
have. They're pinkish.

http://ioannis.virtualcomposer2000.c...ope/amici.html
Interestingly, this article says that high-pressure sodium vapor lamps
are the leading cause of light pollution.

And Jack Horkheimer didn't tell that to you. He knows better.


No, actually, the tour guide at Lick Observatory told me and I can see
the lamps for myself any evening in Silicon Valley.

  #14  
Old December 24th 08, 09:29 PM posted to alt.astronomy
Timberwoof[_2_]
external usenet poster
 
Posts: 799
Default Normal Constellation of the Stars

In article ,
Saul Levy wrote:

Yes those are LOW-PRESSURE sodium vapor lamps, woofie.

I always thought they should look yellow, but they look pink to me
too. The eye (brain?) can lie!

Astronomers love them!

High-pressure sodium vapor lamps are very similar to mercury vapor
lamps in that they use a lot more of the spectrum for it's emissions.
Low-pressure mainly emits two spectral lines.


Well, now. Since you're playing the game of "Shoot Holes in the Post". I
shall join in on the fun. You've contradicted yourself. Low-pressure
sodium vapor lamps emit mainly two (yellow) spectral lines; thus they
look yellow. Since the high-pressure sodium vapor lamps emit across more
of the spectrum, their light is whiter ... but in this case pinkish.

See: http://en.wikipedia.org/wiki/Sodium_vapor_lamp


Huh. The low-pressure sodium lamp looks yellow to me.

Huh. The high-pressure sodium lamp spectrum looks like discrete emission
lines, not like blackbody radiation which would blanket everything. And
oh, look! "Most of the other green, blue and violet lines arise from
mercury", from your own reference. So I was not so far off to begin
with.

and

http://ioannis.virtualcomposer2000.c...ope/amici.html
see the 1.4.x pictures.

It's the blue and UV emissions which astronomers hate.


Blue and UV are troublesome because the atmosphere scatters them more,
hence out blue sky. But astronomers are irritated at all additional
light in the atmosphere but are willing to make compromises, such as
lamps that emit principally in specific wavelengths, leaving the rest of
the spectrum relatively free.


Saul Levy


On Tue, 23 Dec 2008 22:45:25 -0800, Timberwoof
wrote:

In article ,
Saul Levy wrote:

On Tue, 23 Dec 2008 01:06:28 -0800, Timberwoof
wrote:


Mercury vapor lights are a disaster for astronomy, woofie!


I misremembered. The mercury vapor lights were replaced...
http://mtham.ucolick.org/public/ligh...peration2.html

You mean sodium vapor.


But not with low-pressure sodium vapor lights. Those emit a
characteristic yellow light which the street lights of San Jose do not
have. They're pinkish.

http://ioannis.virtualcomposer2000.c...ope/amici.html
Interestingly, this article says that high-pressure sodium vapor lamps
are the leading cause of light pollution.

And Jack Horkheimer didn't tell that to you. He knows better.


No, actually, the tour guide at Lick Observatory told me and I can see
the lamps for myself any evening in Silicon Valley.


--
Timberwoof me at timberwoof dot com http://www.timberwoof.com
Most of the universe is extremely hostile to life as we know it. It seems
obvious that it was all designed by some creature that hates life... And here
you are, trying to attract its attention.
  #15  
Old December 25th 08, 01:29 PM posted to alt.astronomy
Saul Levy Saul Levy is offline
Banned
 
First recorded activity by SpaceBanter: Jul 2006
Posts: 21,291
Default Normal Constellation of the Stars

Splitting hairs aren't you, woofie? lmfjao!

High pressure lamps swamp out areas of the blue and UV which
astronomers have been using for many years. That's why they hate
them. The sodium D lines aren't anywhere near as important.

Saul Levy


On Wed, 24 Dec 2008 13:29:54 -0800, Timberwoof
wrote:

In article ,
Saul Levy wrote:

Yes those are LOW-PRESSURE sodium vapor lamps, woofie.

I always thought they should look yellow, but they look pink to me
too. The eye (brain?) can lie!

Astronomers love them!

High-pressure sodium vapor lamps are very similar to mercury vapor
lamps in that they use a lot more of the spectrum for it's emissions.
Low-pressure mainly emits two spectral lines.


Well, now. Since you're playing the game of "Shoot Holes in the Post". I
shall join in on the fun. You've contradicted yourself. Low-pressure
sodium vapor lamps emit mainly two (yellow) spectral lines; thus they
look yellow. Since the high-pressure sodium vapor lamps emit across more
of the spectrum, their light is whiter ... but in this case pinkish.

See: http://en.wikipedia.org/wiki/Sodium_vapor_lamp


Huh. The low-pressure sodium lamp looks yellow to me.

Huh. The high-pressure sodium lamp spectrum looks like discrete emission
lines, not like blackbody radiation which would blanket everything. And
oh, look! "Most of the other green, blue and violet lines arise from
mercury", from your own reference. So I was not so far off to begin
with.

and

http://ioannis.virtualcomposer2000.c...ope/amici.html
see the 1.4.x pictures.

It's the blue and UV emissions which astronomers hate.


Blue and UV are troublesome because the atmosphere scatters them more,
hence out blue sky. But astronomers are irritated at all additional
light in the atmosphere but are willing to make compromises, such as
lamps that emit principally in specific wavelengths, leaving the rest of
the spectrum relatively free.


Saul Levy


On Tue, 23 Dec 2008 22:45:25 -0800, Timberwoof
wrote:

In article ,
Saul Levy wrote:

On Tue, 23 Dec 2008 01:06:28 -0800, Timberwoof
wrote:


Mercury vapor lights are a disaster for astronomy, woofie!

I misremembered. The mercury vapor lights were replaced...
http://mtham.ucolick.org/public/ligh...peration2.html

You mean sodium vapor.

But not with low-pressure sodium vapor lights. Those emit a
characteristic yellow light which the street lights of San Jose do not
have. They're pinkish.

http://ioannis.virtualcomposer2000.c...ope/amici.html
Interestingly, this article says that high-pressure sodium vapor lamps
are the leading cause of light pollution.

And Jack Horkheimer didn't tell that to you. He knows better.

No, actually, the tour guide at Lick Observatory told me and I can see
the lamps for myself any evening in Silicon Valley.

 




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