Environment guide

Heralding a new age in the cosmos, Norwegian Kristian Birkeland predicted that the universe likely consisted of an exotic component that would later be called dark matter. His comments about this subject matter appeared in a description of the Norwegian Aurora Polaris Expedition (1902-1903). Birkeland’s ideas about the Expedition were published in the fateful year of 1913 which would see the rise of the socialist Federal Reserve System and the Income Tax in the United States of America, two key components of the communist manifesto. Evolutionary processes were in motion throughout all fields of endeavor. Economics, politics, science and the hearts and minds of men and women were in the balance whilst relativism not truth held sway over the modern imagination. Cosmology would suffer from the same ‘evolutionary’ mindset and Birkeland wrote as much:

“We have assumed that each stellar system in evolutions throws off electric corpuscles into space. It does not seem unreasonable therefore to think that the greater part of the material masses in the universe is found, not in the solar systems or nebulae, but in “empty” space.”

In this fashion, Birkeland predicted that because of the ‘evolutions’ present within the cosmos most of the matter in the universe must be found in ‘empty’ space rather than that which is observable in stellar objects. It is currently believed that only four percent of the universe is of this ordinary visible stellar type. Further, about a quarter of the universe is made up of the ubiquitous dark matter with the rest of the cosmos being filled with the even more bizarre dark energy. It was Fritz Zwicky, a swiss astrophysicist working for Caltech, who would further the concept of dark matter through the aegis of the Virial Theorem.

This mathematical relation is a formula which bounds the energy of a set of particles. In another dark year in the steady evolution to slavery since 1933 saw the removal of gold from the accounts of american citizenry, Zwicky used the Virial Theorem in an attempt to ascertain the validity of the dark matter hypothesis. He focussed his attention on the Coma galactic cluster and his analysis provided prima facie confirmation for the existence of dark matter. By evaluating the amount of movement of those galaxies at the periphery of the cluster he was able to approximately surmise the aggregate of all the matter therein.

He was astonished to learn that this sum total of mass is different from a separately computed estimate. This other value was obtained by analyzing the sum total of galaxies and the brightness of the Coma cluster. Juxtaposing this value with the periphery computation he observed that there was a discrepancy of at a minimum four hundredfold. Since the galaxies were insufficiently massive to cause the computed orbital velocities there must be some other mechanism to explain this phenomena. This conundrum became in the scientific lexicon the missing mass problem. Zwicky had established the need for the existence of an invisible source of mass hitherto unknown which must provide the necessary gravitational effect for the cluster.

Thus, it is a fact of the current state of cosmology that the greatest set of evidence for dark matter comes from this galactic gravitational data. Scientists have even made galactic curves describing the rotational properties of stars versus the distance from the galactic center. When the gravitational data is plotted it can be shown that only a small portion of the observed speeds are explicable by classical computations. In other words, there is a scarcity of visible mass in the observed galaxies to attribute the sum total of gravitational effects to visibly observable stars planets and galaxies. Thus, the simplest way to explain this galactic mystery of insufficient mass is to hypothesize a non-detectable type of mass known as dark matter which can be the cause for the gravitational effects.

As more and more data is collected on these and other aspects of the universe, formulae and cosmological postulates are generated describing the results so obtained. Fulfilling the requirements of the aforementioned aspects leads some scientists to propose several different types of dark matter. The four main types of dark matter are called 1- baryonic dark matter; 2- warm dark matter; 3- cold dark matter and 4- hot dark matter. Dark matter ranges from the known to the predicted, from black holes to brown dwarfs to the massive compact halo objects (MACHOs), the neutrino, axions, WIMPS or weakly interacting massive particles and the esoteric neutralino. However, there is an alternative explanation for the gravitational effects which originally created the dark matter concept.

If an incomplete understanding of gravitation is factored into the picture, then it can be asserted that the dark matter interpretation is incorrect because some other cause is generating these phenomena. Several different contending theories have been developed to describe the observed galactic data. In particular, one of the main competing explanations is given by scalar tensor theories which try to combine the teachings of quantum mechanics with gravity. Amplifying these ideas leads to a variety of exotic ideas which challenge our most fundamental notions of physics and astronomy. Other concepts go even further and have been the subject of interest for astronomers like Dr. Riccardo Scarpa since these allow for a cosmology without the inclusion of the enigmatic dark matter.

Dr. Scarpa works at the European Southern Observatory in Santiago Chile using the Very Large Telescope Array at Paranal. With all of his experience in this field, it is interesting to note some of his most recent comments on the superfluous dark matter:

“Dark matter is the craziest idea we’ve ever had in astronomy. It can appear when you need it, it can do what you like, be distributed in any way you like. It is the fairy tale of astronomy.”

In view of these comments one should ask if another scientific idea might be on the verge of collapsing. Indeed, astronomers are routinely using these other theoretical principles on a daily basis in infrared observatories around the world. Thus, it is very likely that we are simply wrong about all of this dark matter. It is within all probability that the only dark matter that we will ever find is that ignorant dark matter between our ears.]]>

http://www.snapjunky.com

With such a fantastic device as the digital camera for the recreation of magic in arts, a lot of care needs to be taken so as to maintain the perfection of the end product. This perfection is not only obtained by the artistic feeling of the photographer but also with the intricate knowledge of every minute aspect of the medium of creation of art (in this case the digital camera). And these minute aspects play a vast role in defining the ultimate perfection. The digital camera, light and depth of field are one such factor that would come into light in this subsequent discussion. Basically, the depth of field is a measurement of the acceptable sharpness. Yet this is very strictly a personal preference, and varies from person to person. Thus to be more formal, the depth of field can be defined as the area inside an image that demonstrates an ample sharpness that can be considered more or less in focus. So the depth of field is the range of distance, measured along the lens axis, as per which the image is caused to be sufficiently well and sharp in the photograph. The rest is as follows!

The depth of field defines the zone where all elements show clearly from foreground to background. Three factors control the depth of field in an image, they are the distance of the subject, the focal length, and the aperture used to capture the photograph. For people using compact digital cameras, one of the subjects of out of the ordinary interest is the depth of field because depth of field is more easily said than done to control with a compact digital camera than with earlier conventional analog film cameras. The minute imaging sensors of compact cameras need the use of short focal lengths, and this in sequence gives these compact digital cameras an extraordinarily long depth of field when compared to other cameras. Thereby, with intent obtaining a shallow depth of field is more complicated.

Considering a general acceptable fact, the depth of field decreases, as the image gets nearer to the camera. This means that as the focal point reaches closer to the lens, the achievable scope of the depth of field ebbs. On the other side, if the image is far enough distant from the camera, and for digital cameras, this must not be very far, the depth of field approaches out to infinity. Another important point to be noted is that the depth of field is proportional to the lens opening.

Having discussed the above important aspects of the light and depth of field of a digital camera, it is clear that the minute details make such great subjects whose knowledge becomes equally important for making appropriate use of the fantastic device, the digital camera! And the digital camera, light and depth of field comes out to be such important factors that can make all the difference if a photographer remains oblivious about this knowledge. A small factor thus can meal a big divergence!]]>

By Kenneth J. McCormick
Http://aboutfacts.net

Here I am discussing the formation of the universe again. It’s a subject that is fascinating because of all its implications. Tied deeply into this is the age of the universe. But there may be even a bigger question and that is, does age have any relevance when speaking about the universe? You may wonder why I would say something like this. It is astronomical blasphemy. Every astronomer worth his salt talks about seeing back to the beginning of the formation of the universe with telescopes and how we may someday be able to see back to the exact beginning and here I am, mister nobody, saying that they may all be wrong.

Lets look at why I am saying this. We, as mere mortals, really have no idea if the universe has formed before, or for that matter, if it has, how many times. There is a theory that states that we live in an osculating universe. That there was a big bang and matter that was blown out created the stars and galaxies along with the other bodies. It goes on to state further that someday these bodies, which it says are speeding away from each other at a great rate of speed, will begin to slow down and then they will begin to fall back in on themselves until they become one huge mass and then explode again, causing the process to start over. If this goes on over and over, does time have any relevance when we talk of the age of the universe? If this theory is correct then how could we possibly ever know how many times this expansion has occurred or the true age of the universe? The best we could hope for would be to know the time that has passed since the last big bang.

It may turn out that what we think of as the universe is only a tiny piece of a much larger object. I once saw a story on TV about a scientist finding out that we were really living in a gigantic cell in a creature that was made up of billions of these cells. Hey I know this was only a story, but you never really know. Wouldn’t it be something if we reached the end of what we thought of as our universe and found another one, then another and so forth? That may not be so far fetched. If that is the case then we may not be able to tell how the universe was formed, only our little part of it.

Some scientists today believe that there was a big bang but the expansion of the universe will go on forever. Every object will speed away from the next until the universe is a dark and cold place. They think this because they believe that there is not enough matter to slow down the expansion. But most scientists believe in dark matter and they believe that most of the universe is composed of it. The theory goes on to say that it will be the dark matter that will eventually get the expansion to slow down, stop and reverse.

Astronomers believe that they have discovered ripples in space that precede any creation of matter. They state that this discovery proves that there was a big bang. Astronomers used to believe that space all had the same temperature. I am not talking about space right next to a sun but deep space. It wasn’t until COBE, the Cosmic Background Explorer was launched in the 1990s that they found out that they were wrong. There were variations in temperature detected. But not all discoveries have been good for theorists. For many years scientists have believed in the red shift. Simply stated, as objects speed further away their light shifts to the red end of the spectrum. This is used to also judge their distance. Here is where the monkey wrench comes in. Recently one of the farthermost galaxies ever discovered showed up as old not young, but the further out we see, the further back in time we are looking because light takes so long to reach us. So how could this extremely distant galaxy be old? This is a good question. No one has the answer right now; I think they are still all in a state of shock. The implications are that the red shift measurements may not be accurate for every galaxy, maybe a galaxy aged extremely fast for some reason, or maybe there are old galaxies way out there

I like the idea that there may be old galaxies near, what we think is the beginning of our universe. I like it because things may turn out completely different than we thought they were. Maybe we observed the tail end of an adjourning universe and we will find more old galaxies. Another thing, who says there is a law that states that there was only one big bang in one area? I know that Einstein said that the universe was curved and if a beam of light is sent out into space that it will eventually return to the point of origin due to this curve but it does make you wonder, doesn’t it? What is this barrier that won’t allow you outside the curve? Why couldn’t I take a spacecraft with a computer and chart a course that just keeps going straight out? I have a very hard time with this one.

Another thing that I wonder about is physics. Are the laws of physics the same throughout the universe? Maybe parts of the universe formed differently than other parts even though they look similar through a telescope. If I go onto a planet in another galaxy is it possible that gravity may work differently? I drop that apple from a tree and it travels sideways. Scientists would laugh at me for proposing this but I believe that they shouldn’t be too sure of things. There is so much out there that we won’t understand for a long time or maybe never. What if it turns out that the laws of nature are different in our galaxy than any of the others? That would be a shocker. We might even find life that is not carbon based.

When you think about the universe there is just so much to ponder. It truly makes you feel insignificant.

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are the three main types of telescopes. All these
different types have the same purpose, but each
telescope design does it differently. Collecting
light and bringing it to a point of focus so it can be
magnified and examined with an eyepiece is their
goal.

Of the different types of telescopes the refractor
is the telescope most people think of when they
think of astronomy. This type of astronomy telescope
is easy to use and reliable due to the simplicity
of design. It requires little or no maintenance. Its
great for looking at the different types of lunar,
planetary, and binary stars.

Newtonians are a type of telescope, which is also
known as catoptrics. This type is different from
the other telescopes because it has the lowest
per inch of aperture compared to refractors and
Catadioptrics, because lenses are more expensive
to produce than mirrors, especially in medium
to large apertures. Newtonians deliver very bright
images and are low in optical aberrations.

Catadoptric telescopes are the most popular type
of instrument, with the most modern design,
marketed throughout the world in 3 1/2 and larger
apertures. Its very good for looking at different
planetary, lunar, and binary stars. If you like to
take photos with your telescope this type of
instrument is excellent for deep sky observing
or astrophotography with fast films or CCD’s.]]>