APOD 1.5

Our home, Mother Earth. Here, the Earth here can be seen recieving sunlight from pole to pole. Our planet experiences this twice a year: once in the Spring and once in the Fall. In fact, this occurence is called an Equinox (hence the names Spring Equinox and Fall Equinox). During an Equinox, the Earth experiences 12-hours of sunlight and 12-hours of darkness everywhere. This picture was taken about 36,000 kilometers above the Earth's surface on the Fall Equinox (September 22, 2013). However, it wasn't posted until September 28, 2013.

APOD 1.4

This image posted on September 23, 2013 shows the emission nebula just south of the star Antares - located in the constellation of Scorpio. Small stars near the nebula radiate heat which tears the electrons away from the atoms. The electrons eventually recombine with the atom to form light and give the nebula its glow. The nebula itself is said to be located approximately 6000 light-years away and 250 light-years across which would take up the same area as four full moons on the sky.

Biography of Johannes Regiomontanus

Jan Stary

Percival
Astronomy Honors / p. 5
24 Oct. 2013

Johannes Regiomontanus

Johannes Regiomontanus, whose real name was Johann Müller, was born on June 6, 1436, in Königsberg, Franconia (the modern day state of Bavaria located in Germany). His changed name is derived from the Italian name of his birthplace: Königsberg (meaning King’s Mountain). In Latin, this is translated to “Regio monte” which helped derive the modern name Regiomontanus. Regiomontanus’ contributions to astronomy were superb. He not only helped improve observations recorded by his predecessors, but he also introduced trigonometric methods to Europe and more.

 

Johannes Regiomontanus became known as a mathematical and astronomical prodigy from an early age. He was homeschooled until the age of eleven when he had enrolled into the University of Leipzig to study mostly dialectics. Soon after, he had made his way into the University of Vienna where we had become a pupil of Georg von Peuerbach, a mathematician-astronomer, and soon his mentor. The university appealed to him with its activity in mathematical astronomy and cosmology, and its reputation with Peuerbach. Regiomontanus continued his education at the University of Vienne where he had received his baccalaureate in 1452 but did not receive his Master’s Degree until 1457 because the university required him to be at least 21 years of age. The two men had done work together for the remainder of Peuerbach’s life. Peuerbach had pointed out many inaccuracies in the Alphonsine Tables which in the mid-fifteenth century were in need for revision while also pointing out the need for better translations of Greek texts.

 

Before the death of Peuerbach in 1461, he [Peuerbach] was approached, in 1460, by the papel legate to the Holy Roman Empire, Cardinal Bessarion, who had requested that Peuerbach write an abridgement of Almagest. This piece, written around 150 A.D. by Ptolemy, was arguably the most important astronomical contribution up to that date. The two men had begun work on it but soon Peuerbach had passed away with his dying wish being that Johannes Regiomontanus completes the abridgment.  Regiomontanus agrees and moves to Italy as a member of Bessarion’s extended household. There he completes the abridgment and calls it Epitome. This piece of astronomic contribution contains updated information in several areas of mathematical astronomy including the position of Mars which was 2º from its predicted position. In addition to information on Mars, the times predicted in the tables about the time an eclipse of the moon would occur happened to be one hour earlier than its actual occurrence.

 

In Regiomontanus’ later life, he had also written a piece called De triangulis omnimodus which had developed the earliest statements of the law of cosine for spherical triangles and provided tables of tangent values primarily for astronomical work. The book did not appear until 1533 (67 years after his death). Johannes Regiomontanus passed away in July 6, 1476, most likely due to the plague caused by the Tiber River overflowing its banks.

 

Sources

Shank, Michael. "Regiomontanus (German Mathematician)." Encyclopedia Britannica Online.

             Encyclopedia Britannica, n.d. Web.

O'Connor, J. J., and E. F. Robertson. "Johann Müller Regiomontanus." Regiomontanus Biography.

             MacTutor History of Mathematics, June 2004. Web.

Norton, Stephen D. "Johannes Regiomontanus." Science and Its Times. Ed. Neil Schlager and Josh

             Lauer. Vol. 3: 1450 to 1699. Detroit: Gale, 2001. 380-81. Gale Virtual Reference Library. Web.

APOD 1.3

Posted on September 15, 2013, this picture displays a magnificent plethora of colors produced from the death of the star. As the star "dies" and transforms into a white dwarf star (a process that takes over a thousand years) it releases outer gaseous envelopes which forms to artistic display shown in the picture. What is also interesting is that there are two stars in the middle orbiting each other with an orbit ten times the size of Pluto's.