Observations: AstronomyCast X-Ray Astronomy

X-ray astronomy is an observational branch of astronomy which deals with the study of X-ray observation and detection from astronomical objects. X-ray radiation is mostly absorbed by the Earth's atmosphere; therefore, many of the instruments used to measure X-rays are sent up through the atmosphere on balloons, sounding rockets, and satellites. Much of the rays are picked up from celestial objects that emit high temperature gases. The first X-ray source to be identified was from the constellation Scorpius and was called Scorpius X-1. It is now known that such X-ray sources as Sco X-1 are compact stars, such as neutron stars or black holes. Material falling into a black hole may emit X-rays, but the black hole does not. The main energy source for the X-ray emission is gravity.

Observations: AstronomyCast Globular Cluster

Globular clusters are spherical collections of stars that orbit a galactic core as a satellite. Globular clusters are very tightly bound by gravity, which gives them a spherical shape and relatively high stellar densities toward their centers. These globular clusters are common; there are about 150 to 158 known globular clusters in the Milky Way, with more left to be discovered. Other galaxies have many more clusters than even the Milky Way. The Andromeda galaxy has about 500 and galaxy M87 has as many as 13,000. Although it appears that globular clusters seem to have some of the first formed stars in the galaxy, little is known about their role in galactic evolution.

Supernova Remnants

This is the image of the remnant of Kepler's supernova. A supernova remnant (SNR) is the structure resulting from the explosion of a star in a supernova. The supernova remnant is bounded by an expanding shock wave, and consists of ejected material expanding from the explosion, and the interstellar material it sweeps up and shocks along the way. This was a supernovaa that took place in the Milky Way galaxy and is in the constellation Ophiuchus. It is the last supernova to have taken place in our galaxy. It is about 20,000 light years from Earth. It was first observed in northern Italy on October 9, 1604.

APOD 3.8

This is a picture containing three of the planets visible with the naked eye. It contains Venus, Jupiter, and Mercury. The first planet you notice is Venus the brightest object in the western sky. Above Venus, the second brightest object is Jupiter. Mercury is very faint and is only visible briefly after sunset as a faint dot just above the horizon. This picture was taken on Reunion Island looking out to the Indian Ocean.

APOD 3.7

This is a series of pictures taken by the Hubble Space Telescope between 1994 and 2009. This is the result of one of the brightest supernovas ever seen. It occurred twenty-five years ago and scientists have been watching  and waited for the expanding debris from this tremendous stellar explosion to crash into previously expelled material. The collision occurred at speeds near 60 million kilometers per hour and shock-heats the ring material causing it to glow. Astronomers are still studying the mysterious rings.

Dorothea Klumpke Roberts Biography

      Dorothea Klumpke Roberts came form an established family of nine, including her parents. She was born on August 9th, 1861 in San Francisco, California. Her father had moved there in the 1850s along with many others during the Gold Rush. However, he was not successful in that particular field. Although he did not strike it rich, he became a very successful realtor. He eventually met Dorothea Mathilda Tolle and they were married. In 1877, seven children later, Dorothea's family moved to Paris, France and several of her sisters went to schools in Germany and Switzerland. Out of her four sisters and two brothers, a wealth of them became accomplished people of their own. One an artist, another a violinist, one a pianist, and one a neurosurgeon. Dorothea herself went to school to study music but became fascinated with astronomy. She earned her bachelor's degree in the field in 1886 and took up a position at the Paris observatory. There she worked with Guillaume Bigourdan and Lipót Schulhof, and later with the pioneer astrophotographers Paul and Prosper Henry, who were working with a 34 cm refractor and photographing the minor planets, also known as assteroids. Her work consisted of measuring star positions, processing astrophotographs, studying stellar spectra and meteorites. In 1886 Sir David Gill proposed an atlas of the heavens. The idea received enthusiastic support, especially from the Director of the Paris Observatory, Admiral Amédée Mouchez, who suggested an international meeting in Paris. This led to the Carte du Ciel project which required photographing the entire sky and showing stars as faint as the 14th magnitude. The Paris Observatory was required to map a large portion of the sky. Ten years later, Dorothea traveled to Norway to see a solar eclipse. Although the eclipse was a bust, she met her future husband, Dr. Isaac Roberts. He had his own observatory equipped his private observatory with a 50 cm reflector and camera, and a 13 cm Cooke refractor. Five years later, in 1901, the two were married, and Dorothea worked with Roberts on a project to photograph all 52 of the Herschel "areas of nebulosity." Although Roberts died four years later, Dorothea returned to Paris Observatory and spent 25 years processing the plates and Isaac's notes, periodically publishing papers on the results.rothea kept up the research. She published a survey entitled, "The Isaac Roberts Atlas of 52 Regions, a Guide to William Herschel's Fields of Nebulosity" and was awarded the Hèléne-Paul Helbronner prize in 1932 from the French Academy of Sciences for this publication.