Friday, January 27, 2012

APOD 3.2

 About 40,000 light-years across, pretty, irregular galaxy NGC 3239 lies near the center of this lovely field of galaxies in the galaxy rich constellation Leo. At a distance of only 25 million light-years it dominates the frame, sporting a peculiar arrangement of structures, young blue star clusters and star forming regions, suggesting that NGC 3239 (aka Arp 263) is the result of a galaxy merger. Appearing nearly on top of the pretty galaxy is a bright, spiky, foreground star, a nearby member of our own Milky Way galaxy almost directly along our line-of-sight to NGC 3239. Still, NGC 3239 is notable for hosting this year's first confirmed supernova, designated SN 2012A. It was discovered early this month by supernova hunters Bob Moore, Jack Newton, and Tim Puckett. Indicated in a cropped version of the wider image, SN 2012A is just below and right of the bright foreground star. Of course, based on the light-travel time to NGC 3239, the supernova explosion itself occurred 25 million years ago, triggered by the core collapse of a massive star.

Friday, January 20, 2012

APOD 3.1

 A Full Moon rising can be a dramatic celestial sight, and Full Moons can have many names. Captured on January 8 from Östersund, Sweden, this evocative moonrise portrait might make you feel the cold of winter in the north. If you can also imagine wolves howling in the distance then you probably understand why Native Americans would have called it the Wolf Moon, their traditional name for the first Full Moon in January. The photographer reports that no wolves were heard though, as he watched this beautiful Full Moon rise in fading light over the eastern horizon, echoing the yellow color of the setting Sun. Of course, due this year on February 7, the next Full Moon will be the Snow Moon.

Monday, January 16, 2012

Johann Heinrich von Mädler Biography

Orphaned at the age of 19, Johann Heinrich von Mädler was forced to raise his three younger siblings by becoming a private tutor. This allowed him to connect with the businessman William Beer, who would later give Mädler a job at his observatory in 1829. In 1930 Mädler began drawing surface maps of Mars. For the prime meridian of their map, he eventually chose the Sinus Meridiani formation. Using his maps and drawings of Mars, and his knowledge of math, Mädler was able to make a rough calculation of Mar's rotational period to within 13 seconds of the actual period of rotation.B&M-LacusMortis.jpg
Johann Heinrich von Mädler was also one of the first people to make an accurate surface map of the moon, which he published with descriptions in four volumes from 1834 to 1836. His singular efforts to map these celestial bodies should not go forgotten in the sands of time, as he was one of the most important astronomers of the 19th century, not only because of the maps he drew, but because of the accuracy of his calculations of the orbital period of Mars.

Friday, January 13, 2012

APOD 2.8 - Iapetus

See Explanation.  Clicking on the picture will download
 the highest resolution version available.

Saturns moon Iapetus is a vast frozen world, much of it is covered in ice while the rest of it is a mysterious dark  material is of unknown composition. But infrared spectroscopy indicates that it could contain some form of carbon. Iapetus has a strange equatorial ridge that makes it look like a walnut. To help better understand Iapetus NASA sent the Cassini to orbit within 2,000 kilometers of the moon in 2007. It is thought that the dark parts of the moon are less than a meter thick and was formed when dirty ice sublimated.

Friday, January 6, 2012

APOD 2.7

See Explanation.  Clicking on the picture will download
 the highest resolution version available.

5,000 light years across and located 2.3 million light years away in the northern boundaries of Cassiopeia IC 10 is young irregualr dwarf galaxy. It is still very young and there is lots of dust in the galaxy that blocks large portions of the light it produces. The redness of the dust shows that it is made of young stars and still  full of vigorous star formation. IC 10 is the closest known starburst galaxy and has a large population of young, large, and extremely luminous stars.

Thursday, January 5, 2012