Observations

Last night at approximately 9:45 I stepped outsude to do some stargazing with my father.  We saw the teapot from the constellation Sagittarius as well as the constellation Scorpius to the left of the waning gibbous Moon.  Also I saw, almost directly overhead, the zig-zag shaped constellation Cassiopeia. At about 30 degrees to the right of the Moon I could see an extremely bright object, which I guessed to be the ISS since according to the heavens above website, it was supposed to be visible from my location. 

Obervations

Tonight at 11:00 I spotted the summer triangle and the Moon at waning gibbous.  Using my calibrated fist, I estimated the distance from Altair to the Moon to be about 9 degrees and saw that each star was roughly  6 degrees apart creating nearly equal sides.

APOD 1.8

     In this photo there appears to be a strange cloud formation above the sun and it has a noticeably more reddish tint than the yellowish orange surface of the Sun.  This extending loop is actually a solar prominence, which is an area of cooler plasma that allows for light to fall in the visible realm and therefore appears to have more saturated color.  Solar prominences are attached in the photosphere, the area where light is emitted, rather than the sun's corona, which is where the plasma is significantly hotter and made up of ionized gasses that do not emit very much light.  This particular solar prominence, captured by SOHO's Extreme ultraviolet Imaging Telescope (EIT), is the largest that we have on record. It was taken during a coronal mass ejection, which is caused by bursts of solar wind that come from the corona and as plasma is heated to the point that electrons are travelling at the speed of light, a rearrangement of the magnetic field occurs and creates a shock that accelerates the particles resulting in a solar flare.  When the solar flar occurs, gasses are released into space creating these loopy effects.  When a solar prominence is viewed staright on with the sun's surface as the background, they appear as dark sun spots because the cooler plasma does not appear as bright.            



Peurbach Biography

                 Georg Peurbach was born in the town of Peurbach, which makes his formal title Georg of Peurbach, in Austria.  Little information has been found on Peurbach’s early life and the first available record is his graduation from the University of Vienna in 1446 with a bachelor’s degree.  Peurbach received an education mainly in humanities and his knowledge of astronomy was acquired independently through access to the books and instruments of the deceased astronomer John of Gmunden who had taught at the university.   

Peurbach quickly became a fairly well recognized astronomer despite the fact that he had not yet published any material as he travelled through Europe through the years 1448 to 1453.  Peurbach delivered numerous lectures in major European cities and was offered a position to teach at both the university in Padua and at the university in Bologna.    Despite these generous offers Peurbach’s ambition motivated him to strive for more and he wanted to make serious scientific accomplishments rather than limiting himself solely to teaching.  Peurbach wanted to discover the exact positions of the Sun, the Moon and the planets in order to further develop astrology and use scientifically grounded charts to prove events in one’s future.  Astrology and astronomy worked harmoniously together in the fifteenth century despite today’s distinct division between the two studies.   

             Peurbach’s major opportunity came in 1454 when King Ladislas V of Hungary and of Bohemia, who was merely fourteen years old at the time, appointed him court astrologer.   Peurbach was also able to teach at the University of Vienna while serving as court astrologer, but he taught humanities rather than astronomy.  As a truly Renaissance man, Peurbach’s diverse academic background led him to write Latin poems written under a pseudonym When King Ladislas died in 1457 from leukemia after fleeing court to avoid political issues Peurbach was offered an even more attractive offer to become the court astrologer to the famous Holy Roman Emperor Frederick III.  Frederick III had a reputation for being a generous patron of the arts and sciences and specifically in the field of astronomy. 

         Regiomontanus, a student at the University of Vienna , collaborated with Peurbach starting in 1453 and the pair published numerous highly successful works for eight years.  Their first work was titled Theoricae Novae Planetarum, which is translated as New Theories of The Planets, in 1454.  The book detailed Peurbach’s theory on Ptolemy’s idea of planets’ epicycles in which he asserted that the planets motions are controlled by the Sun and are in the forms of solid and spheres.  Peurbach and Regiomontanus made observations on various eclipses and by measuring the durations of the eclipses they discovered that midpoint was eight minutes earlier than predicted by the Alphonsine Tables and translated these findings into an impressive set of calculation tables as well as measuring the obliquity of the ecliptic to be 23:28°.They both also made observations on the phenomenon later called Haley’s comet and created more detailed data tables.  Later Peurbach and Regiomontanus were working on a translation of the Almagest into Greek from the Arabic translation by Gerard of Cremonas upon request by the Greek scholar Bessarion.  However, Peurbach died at the age of thirty eight after only completing six books and on his deathbed he made Regiomontanus promise to finish the translation.  Regiomontanus followed through with his promise and the translation was published in 1463 and was dedicated to Bessarion.  Since Peurbach died at a relatively young age the question of what other discoveries he was capable of making is often  posed.        

APOD 1.7

NGC 2170 is a nebula, which is formed by the remnants of gas blown off by a star, located inside a molecular cloud.  More specifically it is located at the R2 iregion in the constellation Monoceros, or the unicorn as it is commonly called.  Monoceros is a relatively modern constellation formed in 1624 by the German astronomer Jakob Bartsch.  This photo of NGC 2170 was taken with the VISTA survey telescope, which is the largest in the world and is located at the ESO obervatory in northern Chile, in infrared since most new stars are hidden by thick interstellar gas that blocks visible and ultraviolet light and the low temperatures and high densities of the molecular clouds display the most visually appealing effects.  The tendrils and streamers of the nebula are created from interstellar dust by radiation emmitted from the stars and strong particle winds. 

APOD 1.6

This image is of the constellation Orion, or by its common name "The Great Hunter", with its Orion nebula (m42) and the Horsehead nebula located at the center of the sword.  The horsehead gets its dark hue from the interstellar dust which is composed of silicon, carbon and oxygen and when viewed at a greater magnification it truly does look like a head of a horse.  The reddish glow behind the dark head results from the ionization, the loss or gain of an electron, of hydrogen gas by the bright star Sigma Orionis.  The fade effect is created by streams of gas that are funneled by a strong magnetic field.  Also included in this picture is the Flame Nebula which is at the edge of the Orion molecular cloud and is made up of hydrogen gas ionized by a bright and young star that is a  a significant source of ultraviolet radiation.  

APOD 1.5

This picture of Saturn was taken by the Cassini spacecraft in February using infrared light, which is electromagnetic radiation that has longer wavelengths than visible light and is therefore undetectable to humans' eyes.  The picture's colors are artificial in order to make the infrared light visible to our eyes which is why this picture caught my attention and the blue coloration is derived from the Sun's light.  It depicts the auroras, or light displays in the sky at the polar regions that result from ionized nitrogen atoms regaining an electron, of Saturn which are more impressive than Earth's because the gaseous nature of Saturn creates a larger and powerful electromagnetic belt for these auroras to appear in.  Due to the strength of Saturn's magnetosphere, these auroras seen at the polar regions of Saturn are easily created by deflecting a stream of charged particles when they interact with its magnetic field.     

Astronomer Biography Sources

Georg Peurbach Bibliography

Complete Dictionary of Scientific Biography.  Vol. 15.  Detroit: Charles Scribner's Sons, 2008.  p473-479.

Schlager, Neil and Josh Lauer.  Science and Its Times.  Vol. 3: 1450 to 1699.  Detroit: Gale, 2001.  p305.

Robertson, E.F. and J.J. O'Connor.  "Georg Peurbach Biography."  University of St. Andrews, Scotland.  Aug. 2006.  <http://www-history.mcs.st-and.ac.uk/Biographies/Peurbach.html>