http://www.britannica.com/EBchecked/topic/454669/Georg-von-Peuerbach
www.newworldencyclopedia.org/entry/Georg_von_Peuerbach
http://www-history.mcs.st-andrews.ac.uk/Biographies/Peurbach.html
Sunday, October 21, 2012
Observation 1.5
Astronomy Cast Ep. 212
"GPS Navigation"
GPS or Global Positioning System, uses satellites to pinpoint the location of the receiver system and show it on a map. While they are very accurate, they aren't always perfect. The blue circle of error shown on many map applications, is the given area that you are determined to be located in by the satellites, because there aren't enough signals to pinpoint your exact location. But what's cool is that these errors aren't locational areas, but timing errors between satellite signals hitting the receiver! It's pretty amazing to think about how it isn't just location, but a simple timing error that causes such errors in our GPS systems!
"GPS Navigation"
GPS or Global Positioning System, uses satellites to pinpoint the location of the receiver system and show it on a map. While they are very accurate, they aren't always perfect. The blue circle of error shown on many map applications, is the given area that you are determined to be located in by the satellites, because there aren't enough signals to pinpoint your exact location. But what's cool is that these errors aren't locational areas, but timing errors between satellite signals hitting the receiver! It's pretty amazing to think about how it isn't just location, but a simple timing error that causes such errors in our GPS systems!
Observation 1.4
Astronomy Cast Ep. 249
"Schrodinger's Cat"
Everyone's heard of it, but not many people understand it. What IS Schrodinger's Cat? Apparently, Schrodinger's Cat wasn't a cat, but a theory. The theory stated that if a cat was placed in a sealed box with available food and water, once sealed, we have no idea whether the cat was dead or alive. This theory is about probability and how we don't actually know certain things about the unknown, until we observe it.
The theory of the cat is then expanded, to include a substance that might decay releasing a radioactive molecule, adding a gieger counter, and connected to that device a vial of poison. If the molecule is formed, the gieger counter will activate, and then knock over the poison, killing the cat. Since the molecule might or might not be produced, we don't know whether the cat is alive or not, and is therefore BOTH dead AND alive! This is a puzzle that cannot be solved by any means in the end...
"Schrodinger's Cat"
Everyone's heard of it, but not many people understand it. What IS Schrodinger's Cat? Apparently, Schrodinger's Cat wasn't a cat, but a theory. The theory stated that if a cat was placed in a sealed box with available food and water, once sealed, we have no idea whether the cat was dead or alive. This theory is about probability and how we don't actually know certain things about the unknown, until we observe it.
The theory of the cat is then expanded, to include a substance that might decay releasing a radioactive molecule, adding a gieger counter, and connected to that device a vial of poison. If the molecule is formed, the gieger counter will activate, and then knock over the poison, killing the cat. Since the molecule might or might not be produced, we don't know whether the cat is alive or not, and is therefore BOTH dead AND alive! This is a puzzle that cannot be solved by any means in the end...
Observation 1.3
Astronomy Cast Ep. 264
"The Hazards of Spaceflight"
Unlike many Sci-fi shows, spaceflight isn't as easy as it looks, there are lots of factors that get in the way of travel through the final frontier. Many of these are mechanical such as the travel device exploding and all the stages they have to go through to make it to space, and others are human. The human obstacles are the fact that space has no air, and is either extremely hot, or extremely cold. We have to take precautions to insulate spacemen as well as physically possible, or they will die just from the temperatures fluctuating.
I never really realized until I listened to this episode though...but without the constant pressure exerted on the human body by the earth's gravity and atmosphere, we would expand and die...Which is what happens when air leaks from spacesuits...
"The Hazards of Spaceflight"
Unlike many Sci-fi shows, spaceflight isn't as easy as it looks, there are lots of factors that get in the way of travel through the final frontier. Many of these are mechanical such as the travel device exploding and all the stages they have to go through to make it to space, and others are human. The human obstacles are the fact that space has no air, and is either extremely hot, or extremely cold. We have to take precautions to insulate spacemen as well as physically possible, or they will die just from the temperatures fluctuating.
I never really realized until I listened to this episode though...but without the constant pressure exerted on the human body by the earth's gravity and atmosphere, we would expand and die...Which is what happens when air leaks from spacesuits...
Observation 1.2
Astronomy Cast Ep. 267
"Infinities"
The episode starts out by defining what infinity really is, with an example about counting grains of sand on a beach. While it is possible because there is a finite number of grains, it is still impossible for one person to do because the number is so large. However there are things that are impossible to count, not because they are so large, but because they are not finite numbers. It then transitions into explaining that there's more than one kind of infinity! Some are smaller, some are larger, but there is no one infinity!
Infinite numbers exist right under our noses too, take for example all the numbers between 1 and 2...1.1,1.11,1.01...2 In truth, if you kept adding decimals, you could keep going forever!
We've discovered that the universe is still expanding, and is almost flat. So in the end, we don't know if it is infinite or not, but it is almost certainly infinite...just really really big...Kind of like how the Earth was seen in the 18th century. This all just blows my mind! There's so much to even simple numbers that we have yet to fully understand!
"Infinities"
The episode starts out by defining what infinity really is, with an example about counting grains of sand on a beach. While it is possible because there is a finite number of grains, it is still impossible for one person to do because the number is so large. However there are things that are impossible to count, not because they are so large, but because they are not finite numbers. It then transitions into explaining that there's more than one kind of infinity! Some are smaller, some are larger, but there is no one infinity!
Infinite numbers exist right under our noses too, take for example all the numbers between 1 and 2...1.1,1.11,1.01...2 In truth, if you kept adding decimals, you could keep going forever!
We've discovered that the universe is still expanding, and is almost flat. So in the end, we don't know if it is infinite or not, but it is almost certainly infinite...just really really big...Kind of like how the Earth was seen in the 18th century. This all just blows my mind! There's so much to even simple numbers that we have yet to fully understand!
Observation 1.1
Astronomy Cast Ep. 271
This episode, entitled "Who Does What in Space?" discusses the many jobs held by scientists who study space, and what exactly they do. The first job they describe is a Fluxual Mechanic, which is a scientist that studies how stars pass one another and who perform equations relating to astronomy. They then transition over to describing Astromotritists, which are scientists that actually measure space. More specifically, they precisely measure where things are, and plan coordinate systems. Later on, they discuss Astro-biology, which is the study of life in space. While their field is still important, they are a branch of scientists who don't study known solid objects, but theoretical life forms that could exist in the cosmos. This taught me a lot about the different jobs that available related to the universe, I never knew the options were so varied, and so amazing!
This episode, entitled "Who Does What in Space?" discusses the many jobs held by scientists who study space, and what exactly they do. The first job they describe is a Fluxual Mechanic, which is a scientist that studies how stars pass one another and who perform equations relating to astronomy. They then transition over to describing Astromotritists, which are scientists that actually measure space. More specifically, they precisely measure where things are, and plan coordinate systems. Later on, they discuss Astro-biology, which is the study of life in space. While their field is still important, they are a branch of scientists who don't study known solid objects, but theoretical life forms that could exist in the cosmos. This taught me a lot about the different jobs that available related to the universe, I never knew the options were so varied, and so amazing!
APOD 1.8
September 24th 2012
http://apod.nasa.gov/apod/ap120924.html
This picture shows a Nebula in the shape of a "Pencil". What it is, is a shock wave traveling at over 500,000 Km/h. What look like filaments are actually ripples in a sheet of glowing gas. From the angel of the earth, it looks like it's a pencil because we can only see the edge of it. While it looks small in the picture, it's actually about 5 light years long! And if that sounds long, it's only a small remnant of a supernova that happened over 11,000 years ago! This supernova was from the star Vela (the shock wave is called the Vela remnant so I'm assuming we labeled the former star Vela).
http://apod.nasa.gov/apod/ap120924.html
This picture shows a Nebula in the shape of a "Pencil". What it is, is a shock wave traveling at over 500,000 Km/h. What look like filaments are actually ripples in a sheet of glowing gas. From the angel of the earth, it looks like it's a pencil because we can only see the edge of it. While it looks small in the picture, it's actually about 5 light years long! And if that sounds long, it's only a small remnant of a supernova that happened over 11,000 years ago! This supernova was from the star Vela (the shock wave is called the Vela remnant so I'm assuming we labeled the former star Vela).
APOD 1.7
September 25th 2012
http://apod.nasa.gov/apod/ap120925.html
This picture depicts lots of tiny rock bubbles located on the floor of a crater on mars. This picture was taken by the robotic rover Opportunity earlier in September. While scientists have seen them on rocks around the planet, they have not been as densely packed as these bubbles here are. They are believed to have been naturally formed, but it is still unknown how they would have been formed by natural means. This shows that we still have a lot to learn about the red planet. Who knows, maybe they were gas bubbles formed from some event when the surface of the crater was hot enough to be molten? Or maybe they were bubbles from an ancient pool of water, boiling and then hardened by clouds of molten gas and rock? Hopefully, we'll find out soon!
http://apod.nasa.gov/apod/ap120925.html
This picture depicts lots of tiny rock bubbles located on the floor of a crater on mars. This picture was taken by the robotic rover Opportunity earlier in September. While scientists have seen them on rocks around the planet, they have not been as densely packed as these bubbles here are. They are believed to have been naturally formed, but it is still unknown how they would have been formed by natural means. This shows that we still have a lot to learn about the red planet. Who knows, maybe they were gas bubbles formed from some event when the surface of the crater was hot enough to be molten? Or maybe they were bubbles from an ancient pool of water, boiling and then hardened by clouds of molten gas and rock? Hopefully, we'll find out soon!
APOD 1.6
October 7th 2012
http://apod.nasa.gov/apod/ap121007.html
This picture isn't exactly astronomy, but it's still pretty cool and mind blowing. It shows a checkerboard with a cylinder in the top right hand corner, casting a shadow down diagonally on the board. Two squares are lettered, A, and B. A is outside the shadow, and B is directly in its path. At a glance, it appears that A is darker, but they are actually the same color! This is a clear showing that human observations are inadequate for drawing final true conclusions, because if our eyes can be fooled so easily just by colors based on surrounding influences, how can we say for certain that some things in the universe are as we believe at a quick glance? What's really cool though, is if you look for long enough at a single letter (B is faster I've found), then you start to see with your peripherals that they both are in fact the same color without having to see the solution to the puzzle!
http://apod.nasa.gov/apod/ap121007.html
This picture isn't exactly astronomy, but it's still pretty cool and mind blowing. It shows a checkerboard with a cylinder in the top right hand corner, casting a shadow down diagonally on the board. Two squares are lettered, A, and B. A is outside the shadow, and B is directly in its path. At a glance, it appears that A is darker, but they are actually the same color! This is a clear showing that human observations are inadequate for drawing final true conclusions, because if our eyes can be fooled so easily just by colors based on surrounding influences, how can we say for certain that some things in the universe are as we believe at a quick glance? What's really cool though, is if you look for long enough at a single letter (B is faster I've found), then you start to see with your peripherals that they both are in fact the same color without having to see the solution to the puzzle!
APOD 1.5
The Horsehead Nebula (October 21 2012)
http://apod.nasa.gov/apod/astropix.html
This APOD describes the Horsehead Nebula, located in the belt of Orion. The red glow of the Nebula is caused by hydrogen gas which is ionized by Sigma Orionis, a nearby bright star. The Horsehead itself is actually dust that has collected over time, and shadows cast by the dust giving the figure more form. Apparently, the bright spots in the Horsehead are actually stars that are in the process of forming, which was about 1,500 years ago taking into account the speed of light and the distance of the Nebula from the Earth. It's amazing that such a detailed picture could be taken with such a small telescope, just a tenth under a meter in diameter!
http://apod.nasa.gov/apod/astropix.html
This APOD describes the Horsehead Nebula, located in the belt of Orion. The red glow of the Nebula is caused by hydrogen gas which is ionized by Sigma Orionis, a nearby bright star. The Horsehead itself is actually dust that has collected over time, and shadows cast by the dust giving the figure more form. Apparently, the bright spots in the Horsehead are actually stars that are in the process of forming, which was about 1,500 years ago taking into account the speed of light and the distance of the Nebula from the Earth. It's amazing that such a detailed picture could be taken with such a small telescope, just a tenth under a meter in diameter!
Monday, October 15, 2012
Chapter 5 Section 1,2,3 Outlines
Astronomy
Chapter 5 Section 1,2,3 Outline
Section 1:
Optical Telescopes:
-
Telescope: Light bucket, captures as
many photons as possible from a given region of the sky and concentrate them into
a focused beam for analysis.
o
Optical telescopes are designed specifically
to collect the wavelengths that are visible to the human eye.
-
Refracting and Reflecting Telescopes:
o
Refraction is the bending of a beam of
light as it passes from one transparent medium into another.
o
Reflecting telescope uses a lens to
gather and concentrate a beam of light.
o
Prime focus is the primary mirror in a
reflection telescope.
-
Comparing Refractors and Reflectors:
o
Factors that tend to favor reflecting
instruments over refractors:
§ Light
must pass through the lens is a disadvantage of a refracting telescope.
§ As
light passes through the lens, some of it is absorbed by the glass. This causes
problems with visible radiation.
§ A
large lens can be quite heavy, and tends to deform under its own weight.
§ A
lens has two surfaces that must be accurately machined and polished.
-
Types of Reflecting Telescopes:
o
Newtonian Telescope:
§ Named
after Isaac Newton, light is intercepted before it reaches the prime focus and
then is deflected by 90o, usually to an eye piece at the side of the
instrument.
o
Cassegrain Telescope:
§ Named
after Guillaume Cassegrain, the point behind the primary mirror where the light
from the star finally converges is called the Cassegrain focus. Requires
starlight to be reflected b several mirrors.
Section 2:
-
Light-Gathering Power:
o
Collecting area:
§ The
total area capable of gathering radiation.
-
Resolving Power
o
Angular resolution:
§ The
factor that determines our ability to see fine structure.
o
Diffraction:
§ The
tendency for light to bend around corners
o
Diffraction-limited resolution:
§ The
amount of diffraction increases in proportion to the wavelength used, and
observations in the infrared or radio range are often limited by its effects.
Section 3:
-
Image Acquisition:
o
Charge-coupled devices (CCD’s):
§ Electronic
detectors that aquire data of stars, they lead directly into computers.
o
Pixels:
§ Tiny
picture elements, they make up an image.
-
Image Processing:
o
Background noise:
§ Anything
that corrupts the integrity of a message, such as static on an AM radio or the “snow”
on a TV screen.
-
Wide-angle Views:
o
Large reflectors are very good at
forming images of narrow fields of view, wherein tall the light that strikes
the mirror surface moves almost parallel to the axis of the instrument.
-
Photometry:
o
Telescopes act as high power cameras
when a CCD is placed at their focus.
o
Photometry:
§ The
measurement of brightness.
o
Photometer:
§ A
device that records highly accurate and rapid measurements of light.
-
Spectroscopy:
o
Spectrometers:
§ Devices
that read the spectrum of light given off by stars and light.
Friday, October 12, 2012
Georg Von Peurbach Biography
Thomas Pring
Mr. Percival
D.E. Astronomy, 2
12 Oct 2012
Georg
Von Peurbach
Georg Von Peurbach was born on May 30th 1423,
and died on April 8th 1461. Unfortunately, not much is known about
his life before he entered the University of Vienna. There, he received the degree
of master of philosophy and the free arts around the year 1440. He also received
Bachelor of the Arts in 1448, and later his Master of Arts in 1453. He spent
much of his life in Vienna, and was both born and died there. He was offered
many professorships while he traveled northern Italy, giving lectures on
astronomy, but turned them all down and returned to Vienna.
He was an Austrian astronomer and mathematician, and is
considered to be a founder of observational and mathematical astronomy in the
West. He was a believer in a Helio-Centric solar system, as shown by his best
known work, Theoricae Novae Planetarum.
This work influenced famous astronomers in the future such as Nicolaus
Copernicus, Galileo Galilei, and Johannes Kepler. His work combined the “homocentric
spheres” believed by philosophers such as Aristotle to be the organization and
orbital explanations of the solar system, with Ptolemy’s epicycle trains
belief.
Georg worked with his student and colleague Johannes
Muler von Konigsberg (also known by his pseudonym Regiomontanus), for years on
countless projects. They made observations on what we call Halley’s Comet in
1456, but are still not acclaimed as the first to discover it. They also were
witness to a lunar eclipse on September 3rd 1457. While he made
observations on astronomical objects and events, he also is credited as the
inventor of many scientific instruments. Some of these instruments include the
regula, the geometrical square.
He brought the Hindu-Arabic numeral system into play with
astronomy, by having his pupil create a shortened version of Ptolemy’s Almagest, and replaced all of the “Chords”
with sines. He calculated the sines for every minute of arc for a radius of
600,000 units, putting them all into a table. This was the first known
transition for scientists from the duodecimal, to the decimal system.
Georg did not have many tools or sensitive instruments at
his disposal, so many of his observations were made with simple ones that were
common in his time period. He used things such as a plumb-line to measure the
angles of elevation of the stars. This most likely prompted him to design and
invent new instruments that would help his studies.
Before his death, he was invited into Rome to study
Ptolemy’s works in their original Greek form, instead of having to continue
reading the Latin Translation he had access to. This translation would be
incorrect in many ways, as the translation process would be skewed without
direct translations between words in the two languages. Having taken up the
offer, he set off to Rome, with the condition that his pupil be brought along.
While he was studying however, he died, leaving Regiomontanus to complete his
studies on his own.
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