Distance Calculations

[GaryN]

I admit it, I'm a math(s) failure, so if someone is willing and able,
I have a calculation, just as a matter of interest, I'd like to see
answered.
I was wondering with Venus, given its size, distance, albedo, what size
light-bulb, at what distance, assuming the availability of a large, dust
free dark space, would that equate to?
A search on the internet though, did bring up an interesting site that
had worked out how far the Sun should be visible from, or rather invisible
from. At 6.09 LY it would not be visible to the eye. They went on to
calculate that the visual limit of Hubble would be 2175 LY, and its
photographic limit at 11.9 KYA.
I haven't read the whole site, but from what I have read, I am really confused.
BS, or is our present view BS?

http://astronomyinformation.org/astronomy/2.htm

[nick c]

hi Gary,

A search on the internet though, did bring up an interesting site that
had worked out how far the Sun should be visible from, or rather invisible
from. At 6.09 LY it would not be visible to the eye.

No. I think that you misread the link. The Sun would be a fairly bright star at 6 LY.

This means that the sun from a distance of 50.71 light-years would be barely visible to the naked-eye.

http://astronomyinformation.org/astronomy/2.htm

Nick

[GaryN]

I looked again Nick.
The opening paragraph with the 50.71 figure starts with
"It is regarded as established fact" and ends with "Other studies however
raise doubts about this particular calculation."
There are then some calculations, and the statement that "the Sun from a
distance of 6.09 light years would not be visible to the naked eye."
Did you only read the first paragraph?
I'm going to make time to read more of the document, it goes on to
discuss parallax and redshift, and has lots of pretty pictures and diags.
Gary.

[nick c]

hi Gary,
Yes, you are correct the link does go on to put the 6.09 ly limit for naked eye visibility of the Sun, my mistake! nevertheless, I think the 50 ly distance is reasonable. The 6.09 limit seems, intuitively, way to low of an estimate for the visibility threshold. It comes down to a question of absolute magnitude for the Sun. Most calculations that I have seen, depending upon the wavelength of light, put the Sun's absolute magnitude in the neighborhood of magnitude 4, this is how bright the Sun would look from a distance of 10 parsecs or about 32 ly. A magnitude of 4+ is well within the naked eye limit. which is usually about 6th magnitude given a nice dark sky, maybe like one of the stars in the Little Dipper, other than Polaris.
It seems to me that the measuring apparent brightness of the Sun on the conventional magnitude scale and calculating the brightness at a standard (10 parsecs,approx 32 ly) distance is relatively straightforward.
No?

[GaryN]

Hi Nick

It seems to me that the measuring apparent brightness of the Sun on the conventional magnitude scale and calculating the brightness at a standard (10 parsecs,approx 32 ly) distance is relatively straightforward.
No?

Not to me. I have more references to check out, but so far I am beginning
to see that absolute parallax, which up to now I had believed to be our
only reliable method of distance measurement, may indeed be bogus.
Relative motion parallax, from what I have seen so far, looks to be based
on assumption, estimates, and a whole lot of self referential mathematics.

Albert Einstein
The only real valuable thing is intuition.

My math sucks for one thing, but to try and calculate anything, based on
numbers that are estimates and assumptions is futile. My intuition tells
me that based on the information available, some of the stars we can see
with the naked eye would require the ability to view a light the size of
a regular 100 watt bulb from around the distance to the moon, but it
could be more extreme than that, down to a pinhead size light!
Redshift is even more ridiculous, totally unreliable for anything if we
are using wrong assumptions. I can think of only one person who might be
able to answer my questions, so I will be contacting Miles Mathis once
I have my proposal and appropriate references organised.
Watch this clip with Patrick Moore asking Niel Armstrong if they could see
the stars, and re-watch it until the significance sinks in. This clip has been
used by the Moon landing hoax crowd to bolster their case, but if they did
go to the Moon, and I believe they did, the implications are mind-boggling.
http://video.google.com/videoplay?docid ... 9580790620#
If Bahram Katirai was correct with his fundamental proposals, then welcome
to your new Universe. Sizes may vary.

(I'll be very surpried if this post doesn't get the thread 'sent down' )

[allynh]

Measuring distance by parallax is basic surveying, it's only limited by the baseline. We can only measure out so far before the error makes distance a guess. All other ways of measuring distance is guessing, with unacceptable error. The Wiki page says the latest limit is 1,600 lyr, but I would need to know how the Hipparcos satellite measures stuff before I believe that. To measure real distance you have to have telescopes out at Pluto's orbit to broaden the baseline.

Parallax
http://en.wikipedia.org/wiki/Parallax

Proper motion
http://en.wikipedia.org/wiki/Proper_motion

Hipparcos
http://en.wikipedia.org/wiki/Hipparcos

Here is the HyperPhysics page with examples and equations. There is even a calculator for magnitude.

Stellar Parallax
http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html

Here are Wolfram Demonstration Projects.

Parallax
http://demonstrations.wolfram.com/Parallax/

Brightness and Magnitude
http://demonstrations.wolfram.com/Brigh ... Magnitude/

Stellar Luminosity
http://demonstrations.wolfram.com/StellarLuminosity/

Astronomical Units of Length
http://demonstrations.wolfram.com/Astro ... sOfLength/

Radius and Temperature of Main Sequence Stars
http://demonstrations.wolfram.com/Radiu ... enceStars/

Then there are these fun ones.

Celestial Map of Constellations, Stars, and Planets
http://demonstrations.wolfram.com/Celes ... ndPlanets/

Kepler's Mysterium Cosmographicum
http://demonstrations.wolfram.com/Keple ... graphicum/

I'm reading Immanuel Velikovsky: The Truth Behind the Torment, by Ruth Velikovsky Sharon, and she mentions that Harlow Shapley is the one who harassed Velikovsky the most, just as he had done to earlier people when his limited view of the universe was challenged. The actual size of the Milky Way is still an estimate, based on unsubstantiated assumptions.

Harlow Shapley
http://en.wikipedia.org/wiki/Harlow_Shapley

The Great Debate
http://en.wikipedia.org/wiki/The_Great_Debate

The Shapley - Curtis Debate in 1920
The Scale of the Universe
http://apod.nasa.gov/diamond_jubilee/debate20.html

As far as the video is concerned, of course they couldn't see stars. They were looking out polarized bubbles tinted with gold onto bright terrain, or is that moonrain, or lunrain. Anyway, there was no place dark to stand, and no time to let there eyes adapt to darkness. Time is oxygen.

The cameras were the same. There was no place dark and the f-stop could not be opened up to accept more light without overexposure.

That is the same problem that people in cities have. There is so much light that they can't see the stars. Most people living in cities today have never seen the night sky as anything but dark. You literally have to go a hundred miles from anywhere to see the night sky. Then your eyes can adapt and the starlit surroundings look bright as day.

That is the heart of Olbers's Paradox. The sky is actually filled with light everywhere you look, but your eyes can't see all of the frequencies.

Olbers' paradox
http://en.wikipedia.org/wiki/Olbers%27_paradox

Olbers's Paradox
http://demonstrations.wolfram.com/OlberssParadox/

[GaryN]

Hi allynh,
Sorry, I didn't word that very well. I understand parallax, didn't mean
the principle was bogus, just its application to stellar distance, without,
like you say, a huge baseline. So they use relative parallaxes. All well and
good, but what Katirai is proposing is that the objects they photograph to
compare over time, might not be distant stars to begin with!
Looking at the Oort cloud model, he is proposing that the objects they use
give off only the reflected light of the sun, which they can do because they
are much closer than the astronomers believe. Outrageous? How do you prove
him wrong?
(This also messes up the color/age/temperature of the supposed Suns, if the light
is actually reflection from much closer, planetary bodies.)
So looking out from Earth, given the Oort sphere model, you are going to see
a dense band of 'stars' along the equatorial plane, just as we do, but is this a
distant Galaxy disk we see, or just the equatorial band of the above image?
What he is getting at, is that if a telescope can not resolve the distances
stated, then the whole astronomical model falls apart. That is what we would need
to test, and how much should an experiment like that cost? How would it be set up?
As to the Lunar images with no visible stars:

The cameras were the same. There was no place dark and the f-stop could not be opened
up to accept more light without overexposure.

The Moons albedo is around .07, some quote more, but it is not bright. They could
have stood in the shadow of the lander, and taken star photos easily. They said they
could see the stars through an imaging device, even though they still had on the
gold, polarised visor? Their exact actions on the moon would need clarifying.

That is the same problem that people in cities have. There is so much light that they can't see the stars. Most people living in cities today have never seen the night sky as anything but dark. You literally have to go a hundred miles from anywhere to see the night sky. Then your eyes can adapt and the starlit surroundings look bright as day.

On the Earth, the city and town lights are diffused and scattered back. There is
no atmosphere on the moon to scatter what light there was from a low reflectivity
surface. A camera pointed upwards would have no problem photographing the stars.
From 1960, an artists impression of what they thought they would see. Who told the
artist what to draw?

I might be wasting my time with this guy, but until I see where he is obviously
wrong with his base assumption that our eyes, or telescopes can not resolve objects
at the distances claimed, then I'll continue to look at his ideas. If it is all
wrong, he at least has an imagination equal to Stanislaw Lem, and I like that.

[GaryN]

So the mighty Hubble telescope can not even take a decent shot
of our nearest "star".

Why am I to believe this is a star?
And the closest star system. Kind of looks like it could be
another Oort sphere.

Curiouser and Curiouser.

[allynh]

All well and good, but what Katirai is proposing is that the objects they photograph to compare over time, might not be distant stars to begin with!

Oh, I see, my bad. I was using a different lexicon than you or the guy on the astronomy website and we were talking past each other. Ha!

I think I see the problem.

Having agreed that the luminosity of the sun is about 3.83 x 1026 watts,[Luminosity - Fail] the next step would be to determine at what distance its apparent luminosity becomes so faint that a naked eye cannot see it. To do so, the author conducted a simple experiment.[Yikes!] A very small artificial star (diameter 0.33 mm) was created. In a dark room at a distance of 1.3 meters it appeared very much like a star or planet.[5] Surprisingly, at a distance of only about 15 meters, the fiber tip was so faint as to be invisible to the naked eye.[6] The experiment gave us some idea about the limit of luminosity that the naked eye can see. Since the luminosity of the fiber tip in terms of wattage was unknown, it was not possible to calculate how faint its light appeared at the distance of 15 meters.

For the next experiment, a very small (1.7 mm x 3 mm) light bulb was found with wattage (0.0375-watt) determined by the manufacturer[7]. It was found that the light of the mini light bulb, outside the city and away from city light, in a dark and clear night, at the distance of 570 meters, appeared so faint that the naked eye could not see it. Knowing the actual luminosity of the light bulb and the distance that it became invisible, by using the inverse square law of light, we can calculate at what distance a 100-watt light bulb would become equally faint.
0.0375 watts / (570 metes) 2 = 100 watts / d 2
d = 29,434 meters or 29.434 km

This simple calculation indicates that a 100-watt light bulb from a distance of 29.434 kilometres would not be visible to the naked eye.[Unsupported statement - see below]

Since the luminosity of the sun is 3.83 x 1026 watts,[Luminosity - Fail] using the inverse square law we can determine at what distance the light of the sun becomes equally faint.

The following are his footnotes that explain what he did, and show where he went wrong with his basic idea. I'm sure that he measured something, but he didn't measure what he thought.

[4] A simple experiment conducted by Laurence A. Marchall, a teacher at Gettysburg College, which directly gives a rough idea about the luminosity of the sun. For this experiment one simply needs a 100-watt light bulb, a wax photometer made of two pieces of wax separated by a piece of tinfoil and a measuring rod. In order to find the luminosity of the sun we can place a 100-watt light bulb and the sun on opposite sides of a wax photometer and vary the distance from the photometer to the 100-watt bulb until the brightness of bulb at the photometer is the same as the brightness of the sun at the photometer. It was found that the bulb at a distance of about 8cm equals the sun in brightness. Since we have the distance of the photometer to both the light bulb and the sun (1.5 x 1013cm), using the inverse square law we can calculate the luminosity of the sun by the following formula.

The formula simply state; the luminosity of the sun divided by the square of its distance to the photometer, is equal to, the luminosity of the bulb divided to the square of its distance to the photometer.

L sun / d2 sun = L bulb / d2bulb
L sun / (1.5 x 1013cm) 2 = 100 watt / (8 cm) 2
L sun = 3.5 x 1026 watts

This is an approximate value for the luminosity of the sun. However, a more accurate value obtained by highly accurate photometers is 3.83 x 1026 watts.[Luminosity - Fail]

[5] In order to make the small star, a piece of fiber optic was used that had a diameter of 0.33 mm and length of several centimetres. One end of the fiber optic was illuminated by a flashlight so that the light from the other end of the fibre appeared as a small source of light similar to that of a star. The flashlight and parts of the fiber were covered with black tape so that only the light from the tip of the fiber optic was visible.

[6] The experiment was carried out in a large and dark room. Considering the fact that the distance was relatively very short, that the room had been vacant for some time, that no dust or particle was floating in the air, that sufficient time was given for the eyes to get used to the dark, the result of the experiment, as far as the sensitivity of the eye to the light of the fiber tip is concerned, was taken to be roughly accurate.

[7] Mini Lamp: 1.5 volts, 25mA, its size; 1.7 mm x 3 mm. Manufactured in China and distributed by Orbyx Electronics, LLC.

First of all, the 100 watt bulb means that it takes 100 watts to power it, not how much light it puts out. You can have a dozen different brands and styles of 100 watt bulbs, and each one has a different lumen rating.

By using completely different bulbs/light-sources in his experiments, each with different properties, he was trying to state that they were equal. He was mixing apples and oranges.

When astronomy started, the standard light source was the candle. They based their "standard candle" literally on a standard made physical candle.

Candlepower
http://en.wikipedia.org/wiki/Candlepower

Candlepower (abbreviated as cp) is a now-obsolete unit which was used to express levels of light intensity in terms of the light emitted by a candle of specific size and constituents. In modern usage Candlepower equates directly to the unit known as the candela.

History

The term candlepower was originally defined in England by the Metropolitan Gas Act 1860 as the light produced by a pure spermaceti candle weighing one sixth of a pound and burning at a rate of 120 grains per hour. Spermaceti is found in the head of sperm whales, and once was used to make high quality candles.

At this time the French standard of light was based upon the illumination from a Carcel Burner. The unit was defined as that illumination emanating from a lamp burning pure colza oil (obtained from the seed of the plant Brassica campestris) at a defined rate. It was accepted that ten Standard Candles were about equal to one Carcel burner.

In 1909 a meeting took place to come up with an international standard. It was attended by representatives of the Laboratoire Central de l’Electricité (France), the National Physical Laboratory (UK), the Bureau of Standards (United States) and the Physikalische Technische Reichsanstalt (Germany). The majority redefined the candle in term of an electric lamp with a carbon filament. The Germans, however, dissented and decided to use a definition equal to 9/10 of the output of a Hefner lamp.

In 1921, the Commission Internationale de l’Eclairage (International Commission for Illumination, commonly referred to as the CIE) redefined the international candle again in terms of a carbon filament incandescent lamp.
In 1937, the international candle was redefined again against the luminous intensity of a blackbody at the freezing point of liquid platinum which was to be 58.9 international candles per square centimeter.

Since 1948 the term candlepower was replaced by the international unit (SI) known as the candela. One old candlepower unit is about 0.981 candela. Less scientifically, modern candlepower now equates directly (1:1) to the number of candelas[1] — an implicit increase from its old value.

Calibration of lamps

The candlepower of a lamp was measured by judging by eye the relative brightness of adjacent surfaces, one illuminated only by a standard lamp (or candle) and the other only by the lamp under test. The distance of one of the lamps was adjusted until the two were judged to give equal brightness.The candlepower of the lamp under test could then be calculated from the two distances and the inverse square law.

This is what the teacher was doing with the wax paper and measuring rod in note [4] above. He was trying to compare a 100 watt bulb to the sun, using a low accuracy device. One, the 100 watt bulb doesn't mean it was putting out 100 watts, just that it took that much to power it.

It was found that the bulb at a distance of about 8cm equals the sun in brightness.

L sun / d2 sun = L bulb / d2bulb
L sun / (1.5 x 1013cm) 2 = 100 watt / (8 cm) 2
L sun = 3.5 x 1026 watts

Being 8cm from a 100 watt bulb with his handmade rig, means that the error rate of measurement is vast. Comparing 8cm vs. the distance to the Sun, and expecting a valid answer, takes my breathe away. But I digress.

Candle
http://en.wikipedia.org/wiki/Candle

Light

Based on measurements of a taper-type, paraffin wax candle, a modern candle typically burns at a steady rate of about 0.1 g/min, releasing heat at roughly 80 W.[3] The light produced is about 13 lumens, for a luminous efficacy of about 0.17 lumens per watt (luminous efficacy of a source), a hundred times lower than an incandescent light bulb.

The luminous intensity of a typical candle is thus approximately one candela. The SI unit, the candela, was in fact based on an older unit called the candlepower, which represented the luminous intensity emitted by a candle made to particular specifications (a "standard candle"). The modern unit is defined in a more precise and repeatable way, but was chosen such that a candle's luminous intensity is still about one candela.

So if you want to duplicate the experiment, compare the sun to a "standard candle"; Katirai obviously didn't do that. This is the unsupported statement that Katirai made in the first big quote at the start of this post.

This simple calculation indicates that a 100-watt light bulb from a distance of 29.434 kilometres would not be visible to the naked eye.

If he had stated that he set up a 100 watt bulb, coated white, with known rated lumens, on a pole or hillside, then drove an absolute distances from the 100 watt bulb to see it at night, no moon, with only starlight, then he would have a basis to assume certain values of what can be seen at a distance with the naked eye.

He didn't do that. He took three different light sources of unknown lumen output and made a simple Math error--by mixing apple and oranges--and then extrapolated it to something that he could have confirmed by a physical test.

Now this is the "Luminosity - Fail" I mentioned in the quote:

Having agreed that the luminosity of the sun is about 3.83 x 1026 watts, the next step would be to determine at what distance its apparent luminosity becomes so faint that a naked eye cannot see it.

Luminosity
http://en.wikipedia.org/wiki/Luminosity

In astronomy

In astronomy, luminosity is the amount of electromagnetic energy a body radiates per unit of time. Frequently, the word luminosity may also refer to spectral luminosity, measured either in W/Hz or W/nm.[1]

The luminosity of stars is measured in two forms: apparent (counting visible light only) and bolometric (total radiant energy); a bolometer is an instrument that measures radiant energy over a wide band by absorption and measurement of heating. When not qualified, luminosity means bolometric luminosity, which is measured in the SI units watts, or in terms of solar luminosities, ; that is, how many times as much energy the object radiates than the Sun, whose luminosity is 3.846×1026 W.

Katirai based the luminosity of the Sun on the bolometric value, not the visible value, and then proceeded to kludge up a series of experiments that had nothing to do with measuring total energy.

Lumen (unit)
http://en.wikipedia.org/wiki/Lumen_(unit)

The lumen (symbol: lm) is the SI derived unit of luminous flux, a measure of the power of light perceived by the human eye. Luminous flux differs from radiant flux in that luminous flux measurements (such as lumens) are intended to reflect the varying sensitivity of the human eye to different wavelengths of light, while radiant flux measurements (such as watts) indicate the total power of light emitted.

Bolometer
http://en.wikipedia.org/wiki/Bolometer

A bolometer is a device for measuring the energy of incident electromagnetic radiation.

Astronomy in the past used Absolute magnitude using visible light.

Absolute magnitude
http://en.wikipedia.org/wiki/Absolute_magnitude

Absolute magnitude (also known as absolute visual magnitude when measured in the standard V photometric band) is the measure of a celestial object's intrinsic brightness. In astronomy, to derive absolute magnitude from the observed apparent magnitude of a celestial object its value is corrected from distance to its observer. The absolute magnitude then equals the apparent magnitude an object would have if it were at a standard luminosity distance (10 parsec) away from the observer, in the absence of astronomical extinction. It allows the true brightnesses of objects to be compared without regard to distance. Bolometric magnitude is luminosity expressed in magnitude units; it takes into account energy radiated at all wavelengths, whether observed or not.

Apparent magnitude
http://en.wikipedia.org/wiki/Apparent_m ... lculations

Calculations

As the amount of light received actually depends on the thickness of the Earth's atmosphere in the line of sight to the object, the apparent magnitudes are normalized to the value it would have in the absence of the atmosphere. The dimmer an object appears, the higher its apparent magnitude. Note that brightness varies with distance; an extremely bright object may appear quite dim, if it is far away. Brightness varies inversely with the square of the distance. The absolute magnitude, M, of a celestial body (outside of the solar system) is the apparent magnitude it would have if it were 10 parsecs (~32.6 light years) away; that of a planet (or other solar system body) is the apparent magnitude it would have if it were 1 astronomical unit away from both the Sun and Earth. The absolute magnitude of the Sun is 4.83 in the V band (yellow) and 5.48 in the B band (blue).[41]

All of these measurements have so many assumptions and factors of uncertainty that they can only be considered estimates. Everything comes down to the accuracy and precision of the experiment. I've noticed that the uncertainty factor in measurements is rarely even mentioned in any article or science book, yet that is the heart of the problem as seen in Katirai's pages. The way he made his measurements had a huge factor of error/uncertainty built in to everything he did. What he did was neither accurate nor precise.

Accuracy and precision
http://en.wikipedia.org/wiki/Accuracy_and_precision

In the fields of science, engineering, industry and statistics, the accuracy[1] of a measurement system is the degree of closeness of measurements of a quantity to its actual (true) value. The precision[1] of a measurement system, also called reproducibility or repeatability, is the degree to which repeated measurements under unchanged conditions show the same results.[2] Although the two words can be synonymous in colloquial use, they are deliberately contrasted in the context of the scientific method.

A measurement system can be accurate but not precise, precise but not accurate, neither, or both. For example, if an experiment contains a systematic error, then increasing the sample size generally increases precision but does not improve accuracy. Eliminating the systematic error improves accuracy but does not change precision.

A measurement system is called valid if it is both accurate and precise. Related terms are bias (non-random or directed effects caused by a factor or factors unrelated by the independent variable) and error (random variability), respectively.

Compare that same system of accuracy and precision to what astronomer's use for measuring stuff.

Cosmic distance ladder
http://en.wikipedia.org/wiki/Standard_c ... rd_candles

Problems

Two problems exist for any class of standard candle. The principal one is calibration, determining exactly what the absolute magnitude of the candle is. This includes defining the class well enough that members can be recognized, and finding enough members with well-known distances that their true absolute magnitude can be determined with enough accuracy. The second lies in recognizing members of the class, and not mistakenly using the standard candle calibration upon an object which does not belong to the class. At extreme distances, which is where one most wishes to use a distance indicator, this recognition problem can be quite serious.

A significant issue with standard candles is the recurring question of how standard they are. For example, all observations seem to indicate that type Ia supernovae that are of known distance have the same brightness (corrected by the shape of the light curve). The basis for this closeness in brightness is discussed below, however the possibility that the distant type Ia supernovae have different properties than nearby type Ia supernovae exists. The use of Supernovae type Ia is crucial in determining the correct cosmological model. If indeed the properties of Supernovae type Ia are different at large distances, i.e. if the extrapolation of their calibration to arbitrary distances is not valid, ignoring this variation can dangerously bias the reconstruction of the cosmological parameters, in particular the reconstruction of the matter density parameter.[7]

That this is not merely a philosophical issue can be seen from the history of distance measurements using Cepheid variables. In the 1950s, Walter Baade discovered that the nearby Cepheid variables used to calibrate the standard candle were of a different type than the ones used to measure distances to nearby galaxies. The nearby cepheid variables were population I stars with much higher metal content than the distant population II stars. As a result, the population II stars were actually much brighter than believed, and this had the effect of doubling the distances to the globular clusters, the nearby galaxies, and the diameter of the Milky Way.

To me, that means that we really do not have valid measuring sticks, but I don't think the problem is as extreme as Katirai says. But like you say, it is a cool idea. BTW, I still don't see how you even found that site, the design is the strangest I've come across so far.

The Moons albedo is around .07, some quote more, but it is not bright. They could have stood in the shadow of the lander, and taken star photos easily. They said they could see the stars through an imaging device, even though they still had on the gold, polarised visor? Their exact actions on the moon would need clarifying.

I see the problem, the Moon's low albedo made it possible to walk on the Moon at all. If it were white as snow it would have been blinding.

The Moon's albedo is close to that of a paved parking lot here on Earth. If you have access to a big mall parking lot, on a quiet day stand there, and you are on the Moon. I bet that you need to wear sunglasses despite standing on a black surface. Stand in the shadow of a building or truck and look out over the black parking lot, your eyes are still dazzled.

Yes, on the Moon I suspect that they could have pointed the camera straight up and photographed the stars. The problem is, the cameras were bolted on their chests and they could not point them straight up. If they stood in the shade of the LEM and tried to shoot the stars, they would have been pointing to the horizon, and the blinding brightness of the surface would overexpose the film.

The comment about looking through an "imaging device" to see the stars is when they are back inside the LEM looking through their "Alignment Optical telescope." The thing in the roof of the LEM.

http://en.wikipedia.org/wiki/File:LEM-linedrawing.png

Look at the picture on the Wiki page. All those starless photos are because the f-stop was set so high, while standing in blinding light.

Apollo Lunar Module
http://en.wikipedia.org/wiki/Lunar_Excursion_Module

Back to the Hipparcos mission, and my problem with their claims of being accurate and precise out to 1,600lyr:

Cosmic distance ladder
http://en.wikipedia.org/wiki/Standard_candle#Parallax

Because parallax becomes smaller for a greater stellar distance, useful distances can be measured only for stars whose parallax is larger than the precision of the measurement. Parallax measurements typically have an accuracy measured in milliarcseconds.[2] In the 1990s, for example, the Hipparcos mission obtained parallaxes for over a hundred thousand stars with a precision of about a milliarcsecond,[3] providing useful distances for stars out to a few hundred parsecs.

The Hipparcos mission was in Geostationary transfer orbit, so it's baseline was the same as the Earth based observations, so I can now officially express my "doubt" at the 1,600lyr value claimed by the mission. Ha!

[GaryN]

Yes, on the Moon I suspect that they could have pointed the camera straight up and photographed the stars. The problem is, the cameras were bolted on their chests and they could not point them straight up. If they stood in the shade of the LEM and tried to shoot the stars, they would have been pointing to the horizon, and the blinding brightness of the surface would overexpose the film

.

I have done quite a bit of camera work, flim, digial and video. I was the tech
guy for our local film society for a few years. I think I trump you on this?

There are 12 cameras they left on the moon altogether. Don't tell me none of them could point up.

[GaryN]

It seems Mr.Katirai had not the least inkling of the EM nature of things.
A re-working or extension of some of his ideas to include such, might
make for a quite convincing case.
Seeing as so much of what we are told about cosmology seems to be based
on some assumptions, doubtful measurements, and self-referencing math,
would it be fair to have his, or anyone else's ideas considered as viable
alternatives unless they could be proven false?

[allynh]

There are 12 cameras they left on the moon altogether. Don't tell me none of them could point up.

Ha! I bet they never thought to do so. Remember it was literal minded Engineers that designed everything, know-it-all Scientists dictating what they wanted, where every step was written out and diagrammed, and competitive fighter pilots following those steps. It never occurred to them to schedule taking pictures of the stars. Ha!

BTW, That's a fun new icon you have.

[nick c]

hi GaryN,
I am not sure where you are going with this? but I do not see the mystery in a lack of stars in Apollo photos. The moon's surface is still very bright despite the low albedo, especially when the camera is on the surface. The camera's aperature must be stopped down in order to let in less light, and consequently it cannot record such relatively dim targets such as stars. The human eye works much the same way. Go outside on a clear dark night and look at the sky, you can see a myriad of stars, but then go in the house, standing in the middle of a brightly lit room and look toward a window at the sky. You will not see any stars. Similarly, sit in a field box at a night baseball game on a clear summer night and you will only be able to see a few of the very brightest stars, if any, yet if the lights of the stadium went out, thousands of stars would come into view.

There are 12 cameras they left on the moon altogether. Don't tell me none of them could point up.

The purpose of the cameras was to take photos of surface of the Moon, not the heavens as seen from the Moon. The fact that none of the cameras was pointed toward the sky is probably because they were not designed for that purpose and indeed, there was no reason to do so.

Nick

[jjohnson]

You're right about the stellar photography, Nick.
Any of you ever try to take a photo of the stars at night, just using a point and shoot camera without a tripod or a time exposure? Get any stars?

Just because you can see them doesn't mean a camera will get them, especially if it is trying to take pictures of rocks in sunlight, and the lander. I mean, they used Hasselblads, which don't fall into the junk camera category, and got great shots of rocks and stuff, but those cameras were not intended to take tourist pictures of the stars - that wasn't their mission. It requires too much latitude in sensitivity to shoot those sunlit rocks AND get the stars beyond to show up clearly, too. Standing in the shade and pointing the camera up could have netted a good picture, if the film were fast enough or a stabilized time exposure were taken. Not in the playbook, though.

Our eyes have a great latitude in sensitivity, especially if you let them get dark-adjusted for 10 to 20 minutes. Under good seeing conditions we can see thousands of stars in a night sky (all in our own galaxy, period), but we can't see all of the stars, of course. Stars less than about 6th magnitude are too dim to see even with our eyes. Birds probably can see dimmer stars than we can, but they also have a 4th color receptor and can also see a wider range of "visible" wavelengths than we can, too. If you are interested, there is a whole 'nother world of info on stellar colors and human color vision under various circumstances, and related issues. Google "stellar colors" for starters.

The main reason we use telescopes is to gather more light. The more light you get from a star, the "brighter" it appears to your eye, or to your camera. The dilated pupil has a diameter of only about 7mm. My little 106 mm refractor has about 240 times the light gathering power of my eye. (106/2)² divided by (7/2)² is how to get that. This is how the view through a big 12" to 36" reflector can reveal such a "rich field" of stars. We can't see those unaided. The average camera can't either, if you are thinking about that typical little point-and-shoot. It's not just "magnifying". It's getting a lot more photons per second to work with, and funneling them all into your amazed eyes.

Jim

[GaryN]

The purpose of the cameras was to take photos of surface of the Moon, not the heavens as seen from the Moon. The fact that none of the cameras was pointed toward the sky is probably because they were not designed for that purpose and indeed, there was no reason to do so.

Hi Nick,
It doesn't make sense to me that they would go all that way, and not
have the slightest curiosity about the appearance of the stars. The early
Apollo astronauts had a standard EL 500 and a modified one, which could both
be used hand-held if need be. One of the films they had with them was the
super light-sensitive Kodak 2485, 16,000 ASA film. I dont know which camera
that was used in, but surely it would take an image of SOME stars, considering
I can use ASA 400, or even 200 from down here, without a tripod if I steady the
camera against something solid. They could have stood in a shadow, pointed the camera
straight up. There is no reflected light going in the camera. If they were ordered
NOT to try and take pictures of the stars, even in their own time, that's another
matter.

I am not sure where you are going with this?

Where I am going? Just trying to determine if Science has taken a wrong turn.
I am really attempting to disprove Katirai's proposal that many of the stars we
see are actually Oort sphere planets, much closer than stars at distances they
tell us they are at. If an experiment could be set up to determine just how far a
'replica' star can be imaged from, we go from there. I would need to know how
to set up the experiment, but obviously it is not that simple, as it has never
been done, as far as I know.
Miles Mathis is too busy with his latest paper to be of assistance, though he says
his gut reaction would be that they could be seen, even without an atmosphere to
spread them. He did ask me to take another look at his twinkling paper, where he
does state that the accepted distance figures could be out by 180,000% due to
compounding of errors in the methods used. His paper is an attempt to explain why
stars twinkle, but admits it may not be correct.
However, I think the paper is worth reading for what he has to say about the
current state of astronomy. He takes a swing at many others too. Ouch.
http://milesmathis.com/twink.html