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A little math help here? Wolfram Alpha is being bloody awkward at me...
A triangle has 3 sides. Suppose that one angle is 90°. Suppose that one
side is 1 mile long, and the other side is 24 cm long. What are the
other two angles??
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On 11/24/09 09:13, Invisible wrote:
> A little math help here? Wolfram Alpha is being bloody awkward at me...
>
> A triangle has 3 sides. Suppose that one angle is 90°. Suppose that one
> side is 1 mile long, and the other side is 24 cm long. What are the
> other two angles??
That depends on whether one of those sides is the hypotenuse.
--
"Graphic Artist seeks Boss with vision impairment."
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> A little math help here? Wolfram Alpha is being bloody awkward at me...
>
> A triangle has 3 sides. Suppose that one angle is 90°. Suppose that one
> side is 1 mile long, and the other side is 24 cm long. What are the other
> two angles??
Google "(24 cm / 1 mile) in degrees".
If you want more accuracy then it's going to depend on whether the 1 mile
side is the one opposite the 90 degrees or not.
Google:
"asin(24 cm / 1 mile) in degrees"
or
"atan(24 cm / 1 mile) in degrees"
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>> A little math help here? Wolfram Alpha is being bloody awkward at me...
>
> Google "(24 cm / 1 mile) in degrees".
Ah, good old Google calculator. It may not know how to compute the
Riemann zeta function, but it at least manages to do common math
operations. :-D
Apparently it's 0.00854446724 degrees, which is about 30 seconds. That's
some pretty fricken tiny angle!
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On Tue, 24 Nov 2009 16:13:36 +0100, Invisible <voi### [at] dev null> wrote:
> A little math help here? Wolfram Alpha is being bloody awkward at me...
>
> A triangle has 3 sides. Suppose that one angle is 90°. Suppose that one
> side is 1 mile long, and the other side is 24 cm long. What are the
> other two angles??
http://en.wikipedia.org/wiki/Right_triangle#Trigonometric_ratios_in_right_triangles
--
FE
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Invisible wrote:
> Apparently it's 0.00854446724 degrees, which is about 30 seconds. That's
> some pretty fricken tiny angle!
According to Wikipedia:
"20/20 is the visual acuity needed to discriminate two points separated
by 1 arc minute—about 1/16 of an inch at 20 feet."
So I guess 30 seconds (0.5 minutes) could plausibly be within the range
of normal human vision then.
I just noticed the other night that as I passed under a sign telling me
the motorway exit was in 1 mile, I could already see the green traffic
lights beyond the exit. And those lights can't be much more than 24cm
across...
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Fredrik Eriksson <fe79}--at--{yahoo}--dot--{com> wrote:
> On Tue, 24 Nov 2009 16:13:36 +0100, Invisible <voi### [at] devnull> wrote:
> > A little math help here? Wolfram Alpha is being bloody awkward at me...
> >
> > A triangle has 3 sides. Suppose that one angle is 90°. Suppose that one
> > side is 1 mile long, and the other side is 24 cm long. What are the
> > other two angles??
> http://en.wikipedia.org/wiki/Right_triangle#Trigonometric_ratios_in_right_triangles
This is basic trigonometry which is taught in high schools in most places.
--
- Warp
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> "20/20 is the visual acuity needed to discriminate two points separated by
> 1 arc minute—about 1/16 of an inch at 20 feet."
>
> So I guess 30 seconds (0.5 minutes) could plausibly be within the range of
> normal human vision then.
>
> I just noticed the other night that as I passed under a sign telling me
> the motorway exit was in 1 mile, I could already see the green traffic
> lights beyond the exit. And those lights can't be much more than 24cm
> across...
Hmm, I can see an object perfectly fine with an angle of 10^-9 degrees.
Being able to see something and discriminate between two points is
different.
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Warp wrote:
> This is basic trigonometry which is taught in high schools in most places.
I did say "trivial", didn't I? ;-)
My education didn't include this information. Also, I have no idea how
many centimeters there are in one mile.
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Invisible <voi### [at] devnull> wrote:
> I just noticed the other night that as I passed under a sign telling me
> the motorway exit was in 1 mile, I could already see the green traffic
> lights beyond the exit. And those lights can't be much more than 24cm
> across...
Lights can be seen much easier than other details.
--
- Warp
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Invisible <voi### [at] devnull> wrote:
> My education didn't include this information.
Did your education include anything?
> Also, I have no idea how many centimeters there are in one mile.
Nobody is expected to remember factors and numbers, but you are expected
to be able to do the conversion when you know the factors involved.
--
- Warp
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>> I just noticed the other night that as I passed under a sign telling me
>> the motorway exit was in 1 mile, I could already see the green traffic
>> lights beyond the exit. And those lights can't be much more than 24cm
>> across...
>
> Lights can be seen much easier than other details.
This is what I'm interested in. Are the lights visible from this
distance because they glow? Or would any old object be visible from such
a distance? (Assuming it wasn't the middle of the night, obviously.)
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>> My education didn't include this information.
>
> Did your education include anything?
Long division?
Lots and lots of long division?
Like, for years on end?
Let's face it, I went to a school for stupid people, after all. My exam
results are apparently unprecidentedly high for somebody at that school
- and I only got a B and two Cs.
>> Also, I have no idea how many centimeters there are in one mile.
>
> Nobody is expected to remember factors and numbers, but you are expected
> to be able to do the conversion when you know the factors involved.
Trouble is, while it's easy enough to look up some numbers and do a
calculation, it's somewhat more tricky to figure out whether your answer
is actually right (or total gibberish). Hence I asked for assistence. ;-)
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Invisible <voi### [at] devnull> wrote:
> Warp wrote:
>
> > This is basic trigonometry which is taught in high schools in most places.
>
> My education didn't include this information.
If you sat GCSEs, it did. Of course, if you haven't really used it since then
it's easily forgotten :)
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Invisible wrote:
> This is what I'm interested in. Are the lights visible from this
> distance because they glow? Or would any old object be visible from such
> a distance? (Assuming it wasn't the middle of the night, obviously.)
Would you still be able to see it if you intentionally blurred your vision?
Sure, because the blur makes it bigger, not smaller.
The question is whether you can tell two lights on the same pole apart.
You can see stars that are millions (or more) light years away. That doesn't
mean you can tell whether it's a binary star or not.
--
Darren New, San Diego CA, USA (PST)
You know the kamikaze monsters in Serious Sam
with the bombs for hands, that go AAAAAHHHHHHHH!
I want that for a ring tone.
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>> This is what I'm interested in. Are the lights visible from this
>> distance because they glow? Or would any old object be visible from
>> such a distance? (Assuming it wasn't the middle of the night, obviously.)
>
> Would you still be able to see it if you intentionally blurred your
> vision? Sure, because the blur makes it bigger, not smaller.
And fainter.
> You can see stars that are millions (or more) light years away. That
> doesn't mean you can tell whether it's a binary star or not.
Sure, they're quite far away (!!), but they're also rather large (!!!),
and absurdly bright. ;-)
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Invisible <voi### [at] devnull> wrote:
> > You can see stars that are millions (or more) light years away. That
> > doesn't mean you can tell whether it's a binary star or not.
> Sure, they're quite far away (!!), but they're also rather large (!!!),
Try to calculate how many arc-seconds large the farthest visible stars are.
--
- Warp
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Warp wrote:
> Try to calculate how many arc-seconds large the farthest visible stars are.
If my math is right, the closest star would have to have a diameter of about
4100 times as big as our sun to look the same size as a 24cm street light
does one mile away. (Am I the only one that wonders how we managed to mix
cm with miles?) And that's the *closest* star.
No, I don't remember why I started calculating that.
--
Darren New, San Diego CA, USA (PST)
You know the kamikaze monsters in Serious Sam
with the bombs for hands, that go AAAAAHHHHHHHH!
I want that for a ring tone.
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Invisible wrote:
> Sure, they're quite far away (!!), but they're also rather large (!!!),
> and absurdly bright. ;-)
Yep. It would be interesting to figure out how big vs how far away it would
have to be. I mean, the moon is much smaller, the sun is much larger, but
they both look the same size. Actually, I guess it's linear, so it isn't too
hard to calculate.
By the way, I'm pretty sure stars aren't all that bright. I think it's just
because they're large that they seem bright. I.e., per square inch, I don't
think they're a lot brighter than what you can build on earth easily.
(Brighter than street lights, certainly.)
--
Darren New, San Diego CA, USA (PST)
You know the kamikaze monsters in Serious Sam
with the bombs for hands, that go AAAAAHHHHHHHH!
I want that for a ring tone.
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Darren New <dne### [at] sanrrcom> wrote:
> By the way, I'm pretty sure stars aren't all that bright. I think it's just
> because they're large that they seem bright. I.e., per square inch, I don't
> think they're a lot brighter than what you can build on earth easily.
> (Brighter than street lights, certainly.)
I think that getting something to be 6 million times brighter than the
Sun can be pretty hard...
http://en.wikipedia.org/wiki/Cygnus_OB2-12
--
- Warp
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Warp wrote:
> I think that getting something to be 6 million times brighter than the
> Sun can be pretty hard...
Note that I said "per square inch." Sure, if your star is 92x as big as
the Sun, it's going to be very bright in an absolute sense.
100x the heat of the *middle* of the Sun:
http://www.msnbc.msn.com/id/11732814/
Even the middle of lightning gets 2x as hot as the (presumedly, surface of
the) star you referenced.
As I say, it's all about square inches. The *middle* of the sun is
15,000,000K. The surface is 15,000K. Big difference.
Since a star's surface is essentially a black body, it's pretty easy to
calculate the temperature of it, and other black bodies the same color will
be about the same temperature. So the hottest parts of lava are about the
temperature of the sun's surface, and the hottest parts of a propane flame
are about the same temperature as a blue star.
--
Darren New, San Diego CA, USA (PST)
You know the kamikaze monsters in Serious Sam
with the bombs for hands, that go AAAAAHHHHHHHH!
I want that for a ring tone.
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Darren New wrote:
> As I say, it's all about square inches. The *middle* of the sun is
> 15,000,000K. The surface is 15,000K. Big difference.
Sorry. Should have been 5K, not 15,000K. Indeed, ignore that whole sentence.
Anyway, Sun's surface temperature: 9800F.
Industrial tools: 25,000F.
http://www.x20.org/industrial/plaz50.htm
For $1300 you can have something >2x the heat of the sun in your hand.
--
Darren New, San Diego CA, USA (PST)
You know the kamikaze monsters in Serious Sam
with the bombs for hands, that go AAAAAHHHHHHHH!
I want that for a ring tone.
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"Invisible" <voi### [at] devnull> wrote in message
news:4b0c0220$1@news.povray.org...
> I just noticed the other night that as I passed under a sign telling me
> the motorway exit was in 1 mile, I could already see the green traffic
> lights beyond the exit. And those lights can't be much more than 24cm
> across...
Now calculate the angular extent of most distant star you can see with the
naked eye and explain your mistake <g>.
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"somebody" <x### [at] ycom> wrote in message news:4b0c9afb$1@news.povray.org...
> Now calculate the angular extent of most distant star you can see with the
Never mind. I should learn to read the rest of the thread.
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> This is what I'm interested in. Are the lights visible from this distance
> because they glow? Or would any old object be visible from such a
> distance? (Assuming it wasn't the middle of the night, obviously.)
The fact that it is dark helps a lot, obviously your eye is much more
sensitive then.
According to this page:
http://math.ucr.edu/home/baez/physics/Quantum/see_a_photon.html
A rod in your eye must receive about 5-9 photons over 100 ms to tell your
brain that something is there. That is a pretty damn small amount of light.
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scott wrote:
> According to this page:
>
> http://math.ucr.edu/home/baez/physics/Quantum/see_a_photon.html
>
> A rod in your eye must receive about 5-9 photons over 100 ms to tell
> your brain that something is there. That is a pretty damn small amount
> of light.
And THAT is why when it's dark, everything seems "sparkly", I presume.
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On 11/24/2009 11:11 AM, Invisible wrote:
> This is what I'm interested in. Are the lights visible from this
> distance because they glow? Or would any old object be visible from such
> a distance? (Assuming it wasn't the middle of the night, obviously.)
I would guess that stars are significantly distant enough that their
angular diameter is too tiny to be visible without the aid of the light
they give off.
--
Michael Horvath
mik### [at] gmailcom
http://isometricland.com
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OK, so according to the best data I could get my hands on, Alpha Centuri
A is about 430 light years away, and is 1.227 times the radius of our
Sun, so about 853,400 km across. 430 light years is 4.068x10^15 km.
So, if a triangle has sides of 4.068x10^15 km and 853,400 km on either
side of the right angle, what *the hell* is the small angle?!
By the looks of things, dividing these two distances should give me the
tangent of the angle I seek.
853,400 km / 4.068x10^15 km = 2.098x10^-10
arctan 2.098x10^-10 = 1.2020x10^-8 degrees = 4.327x10^-5 arc seconds
This is a *stupidly tiny number*. If you asked POV-Ray to render this,
and you sent out a million, billion, trillion rays, every single damned
one would completely miss such a tiny object. It seems astonishing to me
that such an absurdly minute object is visible at all - but Wikipedia
claims it is...
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> This is a *stupidly tiny number*. If you asked POV-Ray to render this, and
> you sent out a million, billion, trillion rays, every single damned one
> would completely miss such a tiny object. It seems astonishing to me that
> such an absurdly minute object is visible at all - but Wikipedia claims it
> is...
Good job the real world isn't a backward raytracer then :-)
I suspect even a true point source (ie no physical size) was sending out the
same amount of light from that distance, you would be able to see that too.
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>> This is a *stupidly tiny number*. If you asked POV-Ray to render this,
>> and you sent out a million, billion, trillion rays, every single
>> damned one would completely miss such a tiny object. It seems
>> astonishing to me that such an absurdly minute object is visible at
>> all - but Wikipedia claims it is...
>
> Good job the real world isn't a backward raytracer then :-)
Yeah. Because then we wouldn't be able to see stars... which... would be
bad... somehow. I'm sure. :-)
I guess it's simply the case that all the light gets focused onto a
point smaller than a single light sensor, which never the less registers
that there's some light there. (Also, presumably no lense can ever be
optically perfect...)
The part that really puzzles me as that even on the clearest, most
cloudless night, there are, like, maybe 3 stars visible in the entire
sky. And yet mankind has names for hundreds and hundreds of stars, many
of which are claimed to be "visible to the naked eye".
I can only presume this must be due to light pollution. (I'm not saying
that MK's street lighting is inefficient, but... you *can* tell where
the city is from about 15 miles away just by the fact that one entire
side of the night sky is glowing at the exact wavelength of the Sodium
D-line...) Still, even on school caving trips in the middle of nowhere,
I don't recall seeing many stars in the night sky. I presume they're
still there, we just can't see them any more.
> I suspect even a true point source (ie no physical size) was sending out
> the same amount of light from that distance, you would be able to see
> that too.
Well, photons are quantum, right?
(Interestingly, I'm told it *is* possible to make a light source that
emits individual photons, one at a time, on que. And that when you do
this, things like the double-slit experiment still show multiple waves
interferring and reinforcing - despite this being obviously
impossible... Wave-particle duality is weird!)
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Invisible <voi### [at] devnull> wrote:
> OK, so according to the best data I could get my hands on, Alpha Centuri
> A is about 430 light years away
Um, I'm pretty sure that should be 4.3 lightyears.
http://en.wikipedia.org/wiki/Alpha_centauri
That will make your numbers a little more sensible. There are very few naked-eye
stars that are as far as 400 lightyears - only highly luminous giants like
betelgeuse.
:)
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>> OK, so according to the best data I could get my hands on, Alpha Centuri
>> A is about 430 light years away
>
> Um, I'm pretty sure that should be 4.3 lightyears.
>
> That will make your numbers a little more sensible. There are very few naked-eye
> stars that are as far as 400 lightyears - only highly luminous giants like
> betelgeuse.
>
> :)
EPIC FAIL. >_<
Maybe I should just go away and live in a box somewhere. :-S
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Invisible <voi### [at] devnull> wrote:
> The part that really puzzles me as that even on the clearest, most
> cloudless night, there are, like, maybe 3 stars visible in the entire
> sky. And yet mankind has names for hundreds and hundreds of stars, many
> of which are claimed to be "visible to the naked eye".
>
> I can only presume this must be due to light pollution.
Entirely. There are over a thousand stars visible to the naked eye.
http://en.wikipedia.org/wiki/Naked-eye_stars#Naked_eye_in_astronomy
There is nothing like spending a couple of hours on your back in a field with a
truly dark sky - it feels like there are far more than mere thousands visible!
:o
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Bill Pragnell wrote:
> Invisible <voi### [at] devnull> wrote:
>> The part that really puzzles me as that even on the clearest, most
>> cloudless night, there are, like, maybe 3 stars visible in the entire
>> sky. And yet mankind has names for hundreds and hundreds of stars, many
>> of which are claimed to be "visible to the naked eye".
>>
>> I can only presume this must be due to light pollution.
>
> Entirely. There are over a thousand stars visible to the naked eye.
>
> http://en.wikipedia.org/wiki/Naked-eye_stars#Naked_eye_in_astronomy
>
> There is nothing like spending a couple of hours on your back in a field with a
> truly dark sky - it feels like there are far more than mere thousands visible!
>
> :o
But where do you have to go? Outer Mongolia?
(Also... where the hell *is* that anyway?!)
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Invisible <voi### [at] devnull> wrote:
> But where do you have to go? Outer Mongolia?
Well, I bet the skies are great there(!), but at least 50 miles from a large
town or city would do in the UK. Simply making sure you can't see an artificial
light source directly by eye will make a big difference. Coastline works well
because you've only got to worry about distance from towns in half as many
directions. Wilderness such as moorland or mountains works best of course
(although steep hills will obstruct part of the sky), but I'm sure you could
find somewhere suitable within a short drive of MK. Also, winter is best because
the cold air holds less moisture and is therefore clearer. Try to make sure the
moon isn't up either, it can produce a surprising quantity of light pollution,
especially when full!
Oh, and pick a cloudless night ;-)
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> Still, even on school caving trips in the middle of nowhere, I don't
> recall seeing many stars in the night sky. I presume they're still there,
> we just can't see them any more.
http://www.astro-travels.com/pictures/Europe-Light-Pollution.jpg
On the above map my house is on the border of a green/yellow region and I
can make out a huge number of stars on a clear night, the Milky Way is also
just barely visible on a really good night. I don't know exactly where MK
is on that map, but it looks a bit red/orange around there :-(
Don't forget you need to go outside for at least 20 minutes or so for your
eyes to get fully adjusted to the dark, initially it might look like only a
dozen or so stars are visible, but after a few minutes you will see hundreds
more.
BTW if you're interested, one of the brightest "stars" in the sky at the
moment is actually Jupiter.
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>> Still, even on school caving trips in the middle of nowhere, I don't
>> recall seeing many stars in the night sky. I presume they're still
>> there, we just can't see them any more.
>
> http://www.astro-travels.com/pictures/Europe-Light-Pollution.jpg
>
> On the above map my house is on the border of a green/yellow region and
> I can make out a huge number of stars on a clear night, the Milky Way is
> also just barely visible on a really good night.
Aren't we *in* the Milky Way?
> I don't know exactly
> where MK is on that map, but it looks a bit red/orange around there :-(
I would suggest that MK is the small red dot just NW of London. (Or if
it isn't, it's in that general direction.)
> Don't forget you need to go outside for at least 20 minutes or so for
> your eyes to get fully adjusted to the dark, initially it might look
> like only a dozen or so stars are visible, but after a few minutes you
> will see hundreds more.
We drove to and from work through lots of wilderness, and at this time
of night it's quite dark even at 5PM. Many of the roads aren't lit.
I don't recall where we get dragged to on our school caving trips, but
we seemingly had to drive for many hours along winding rounds lined with
dry stone walls before reaching the nearest building with electricity.
> BTW if you're interested, one of the brightest "stars" in the sky at the
> moment is actually Jupiter.
Any ideas what the visual angle for that is? ;-)
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> Aren't we *in* the Milky Way?
Yes, and it's quite a flat disc, so looking out from Earth along the plane
of the disc you see a lot more stars than looking out perpendicular to it,
this looks like a brighter band going across the sky.
>> BTW if you're interested, one of the brightest "stars" in the sky at the
>> moment is actually Jupiter.
>
> Any ideas what the visual angle for that is? ;-)
Wikipedia tells me the radius is 71500 km, Stellarium tells me it's 5.224 AU
away from us, so googling "2*71500 km / 5.224 AU in degrees" gives 0.01
degrees.
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>> Aren't we *in* the Milky Way?
>
> Yes, and it's quite a flat disc, so looking out from Earth along the
> plane of the disc you see a lot more stars than looking out
> perpendicular to it, this looks like a brighter band going across the sky.
I will admit I don't know much about the geometry of our galaxy, but I
was under the impression that the disk is hundreds of billions of light
years "thick", it's just that it's quadrillions of light years across as
well. The point being, the disk is many million stars thick, and so we
should see them in just about every direction we look.
>>> BTW if you're interested, one of the brightest "stars" in the sky at
>>> the moment is actually Jupiter.
>>
>> Any ideas what the visual angle for that is? ;-)
>
> Wikipedia tells me the radius is 71500 km, Stellarium tells me it's
> 5.224 AU away from us, so googling "2*71500 km / 5.224 AU in degrees"
> gives 0.01 degrees.
So... about 36 seconds of arc. Man, that's pretty small.
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"scott" <sco### [at] scottcom> wrote:
> > Aren't we *in* the Milky Way?
>
> Yes, and it's quite a flat disc, so looking out from Earth along the plane
> of the disc you see a lot more stars than looking out perpendicular to it,
> this looks like a brighter band going across the sky.
This is a pretty awesome photo of the whole thing:
http://en.wikipedia.org/wiki/File:Deathvalleysky_nps_big.jpg
Not exactly what you'd see with the naked eye but it gives you the idea.
> >> BTW if you're interested, one of the brightest "stars" in the sky at the
> >> moment is actually Jupiter.
> >
> > Any ideas what the visual angle for that is? ;-)
>
> Wikipedia tells me the radius is 71500 km, Stellarium tells me it's 5.224 AU
> away from us, so googling "2*71500 km / 5.224 AU in degrees" gives 0.01
> degrees.
Jupiter and Saturn are particularly easy to pick out, because they're big enough
to be actual discs rather than points like regular stars. And if you can hold
binoculars steady enough you'll just about see Saturn's rings.
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Bill Pragnell wrote:
> This is a pretty awesome photo of the whole thing:
>
> http://en.wikipedia.org/wiki/File:Deathvalleysky_nps_big.jpg
>
> Not exactly what you'd see with the naked eye but it gives you the idea.
This is awesomer:
http://en.wikipedia.org/wiki/File:Perseid_Meteor.jpg
Here in the name of God does the night sky actually look like this?!
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> I will admit I don't know much about the geometry of our galaxy, but I was
> under the impression that the disk is hundreds of billions of light years
> "thick",
It's much smaller than you think:
http://en.wikipedia.org/wiki/Milky_way
> So... about 36 seconds of arc. Man, that's pretty small.
It's still one of the very few objects in the sky that allows you to
actually see its shape with a good pair of binoculars or a small telescope
though.
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>> I will admit I don't know much about the geometry of our galaxy, but I
>> was under the impression that the disk is hundreds of billions of
>> light years "thick",
>
> It's much smaller than you think:
>
> http://en.wikipedia.org/wiki/Milky_way
Heh, "only" 100,000 light years across and 1,000 light years thick.
Well, that's the trouble when you start dealing with Really Huge
Numbers, see?
There's a reason why would talk about 4 Terabytes rather than
4,000,000,000,000 bytes - it's frighteningly easy to get the number of
digits wrong! ;-)
Obligatory XKCD:
http://xkcd.com/558/
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> This is a pretty awesome photo of the whole thing:
>
> http://en.wikipedia.org/wiki/File:Deathvalleysky_nps_big.jpg
>
> Not exactly what you'd see with the naked eye but it gives you the idea.
I always wonder how they get these type of photos.
I mean this must be a pretty long exposure to get that detail? But since
the Earth is rotating, either the ground or the sky is going to get motion
blurred. Is this a photoshop of two images, or can they really get a photo
like that in one shot?
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Invisible <voi### [at] devnull> wrote:
> This is awesomer:
>
> http://en.wikipedia.org/wiki/File:Perseid_Meteor.jpg
>
> Here in the name of God does the night sky actually look like this?!
Well, that's an even longer exposure than the one I posted (you can tell by the
way the stars are slightly elongated), so no, that's not exactly what you'd see
by eye either. But similar!
A shame there's only one meteor visible there, I was expecting more...
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"scott" <sco### [at] scottcom> wrote:
> > I will admit I don't know much about the geometry of our galaxy, but I was
> > under the impression that the disk is hundreds of billions of light years
> > "thick",
>
> It's much smaller than you think:
>
> http://en.wikipedia.org/wiki/Milky_way
I always remember galactic vital statistics by knowing all the lyrics to this:
http://en.wikipedia.org/wiki/Galaxy_song
:-)
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> I always remember galactic vital statistics by knowing all the lyrics to this:
>
> http://en.wikipedia.org/wiki/Galaxy_song
>
> :-)
Is that something like the song about the table of elements?
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"scott" <sco### [at] scottcom> wrote:
> > This is a pretty awesome photo of the whole thing:
> >
> > http://en.wikipedia.org/wiki/File:Deathvalleysky_nps_big.jpg
> >
> > Not exactly what you'd see with the naked eye but it gives you the idea.
>
> I always wonder how they get these type of photos.
>
> I mean this must be a pretty long exposure to get that detail? But since
> the Earth is rotating, either the ground or the sky is going to get motion
> blurred. Is this a photoshop of two images, or can they really get a photo
> like that in one shot?
I'm not sure. The fact that it's a nearly-complete panorama makes it even more
complicated - I guess it must have been unwrapped from a fisheye.
I'd think it was a single shot. I bet you could get away with up to a minute of
exposure, and it's very wide angle so any movement would be less noticeable.
Any expert photographers here want to comment?
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Invisible <voi### [at] devnull> wrote:
> > I always remember galactic vital statistics by knowing all the lyrics to this:
> >
> > http://en.wikipedia.org/wiki/Galaxy_song
> >
> > :-)
>
> Is that something like the song about the table of elements?
Similar, but more catchy ;-)
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>> Is that something like the song about the table of elements?
>
> Similar, but more catchy ;-)
Heh. I still enjoy listening to TMBG exclaim that "the Sun is a mass of
incandescent gas". ;-)
BUT EVEN WHEN IT'S OUT OF SIGHT THE SUN SHINES NIGHT AND DAY!
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