The Hairy Universe

Feb 25, 2014 Popular accounts of nebulas usually omit mention of their “hairy” structure. Because gravity can’t produce long, evenly spaced filaments of matter, astronomers don’t talk about them. Perhaps they don’t even see them. This double nebula is located in the Large Magellanic Cloud, a small, irregular galaxy that’s considered to…

Continue reading

Ganymede

  Feb 20, 2014 The largest moon in the Solar System shows signs of what could be electric scarring. Jupiter and its moons have been the destination of several deep space missions over the last four decades. Beginning with Pioneer 10 in 1973, and including the most recent visit by  New Horizons, seven different camera…

Continue reading

The Universe in Lace

Feb 12, 2014 Is the recently announced “cosmic web” based on erroneous conclusions? A press release from the University of California, Santa Cruz (UCSC), reports observations of the filamentary structure that comprises the Universe. A nebula exceeding 2 million light-years across, surrounding a quasi-stellar radio source (quasar) known as UM287,…

Continue reading

Dry Water

  Feb 07, 2014 Several previous Picture of the Day articles take issue with the idea that Mars once flowed with liquid water. Since Mars is now a freeze-dried, barren wasteland of rocks and dust, it is presumed that the supposed water features there evaporated over millions of years. When…

Continue reading