South Pole Telescope provides new insights into dark energy and neutrinos
Published: Monday, April 2, 2012 – 15:02 in Astronomy & Space
Analysis of data from the 10-meter South Pole Telescope is providing new support for the most widely accepted explanation of dark energy — the source of the mysterious force that is responsible for the accelerating expansion of the universe. The results also are beginning to hone in on the masses of neutrinos, the most abundant particles in the universe, which until recently were thought to be without mass.
The data strongly support the leading model for dark energy, Albert Einstein’s cosmological constant — a slight modification to his theory of general relativity — even though the analysis was based on only a fraction of the SPT data collected and only 100 of the more than 500 galaxy clusters detected so far.
The complete article may be found at: Dark Energy and Neutrinos
Runaway planets zoom at a fraction of light speed
Published: Thursday, March 22, 2012 – 11:37 in Astronomy & Space
Seven years ago, astronomers boggled when they found the first runaway star flying out of our galaxy at a speed of 1.5 million miles per hour. The discovery intrigued theorists, who wondered: If a star can get tossed outward at such an extreme velocity, could the same thing happen to planets? New research shows that the answer is yes. Not only do runaway planets exist, but some of them zoom through space at a few percent of the speed of light — up to 30 million miles per hour.
“These warp-speed planets would be some of the fastest objects in our galaxy. If you lived on one of them, you’d be in for a wild ride from the center of the galaxy to the Universe at large,” said astrophysicist Avi Loeb of the Harvard-Smithsonian Center for Astrophysics.
For the full story go to – Runaway planets
A star explodes and turns inside out
Published: Thursday, March 29, 2012 – 13:38 in Astronomy & Space
A new X-ray study of the remains of an exploded star indicates that the supernova that disrupted the massive star may have turned it inside out in the process. Using very long observations of Cassiopeia A (or Cas A), a team of scientists has mapped the distribution elements in the supernova remnant in unprecedented detail. This information shows where the different layers of the pre-supernova star are located three hundred years after the explosion, and provides insight into the nature of the supernova. An artist’s illustration on the left shows a simplified picture of the inner layers of the star that formed Cas A just before it exploded, with the predominant concentrations of different elements represented by different colors: iron in the core (blue), overlaid by sulfur and silicon (green), then magnesium, neon and oxygen (red). The image from NASA’s Chandra X-ray Observatory on the right uses the same color scheme to show the distribution of iron, sulfur and magnesium in the supernova remnant. The data show that the distributions of sulfur and silicon are similar, as are the distributions of magnesium and neon. Oxygen, which according to theoretical models is the most abundant element in the remnant, is difficult to detect because the X-ray emission characteristic of oxygen ions is strongly absorbed by gas in along the line of sight to Cas A, and because almost all the oxygen ions have had all their electrons stripped away.
The complete article may be found at: A star turns inside out
‘Time machine’ will study the early universe
Published: Wednesday, April 11, 2012 – 22:33 in Astronomy & Space
A new scientific instrument, a “time machine” of sorts, built by UCLA astronomers and colleagues, will allow scientists to study the earliest galaxies in the universe, which could never be studied before. The five-ton instrument, the most advanced and sophisticated of its kind in the world, goes by the name MOSFIRE (Multi-Object Spectrometer for Infra-Red Exploration) and has been installed in the Keck I Telescope at the W.M. Keck Observatory atop Mauna Kea in Hawaii.
MOSFIRE gathers light in infrared wavelengths — invisible to the human eye — allowing it to penetrate cosmic dust and see distant objects whose light has been stretched or “redshifted” to the infrared by the expansion of the universe.
For the full story go to – Time Machine
Amateur Astronomers Association of Princeton 