Ancient Chinese map of planet Earth’s northern sky is part of the Dunhuang Star Atlas, one of the most impressive documents in the history of astronomy. The oldest complete star atlas known, it dates to the years 649 to 684, discovered at the Silk Road town of Dunhuang
Probing Extreme Matter Through Observations of Neutron Stars
Mar. 6, 2013 — Neutron stars, the ultra-dense cores left behind after massive stars collapse, contain the densest matter known in the Universe outside of a black hole. New results from Chandra and other X-ray telescopes have provided one of the most reliable determinations yet of the relation between the radius of a neutron star and its mass. These results constrain how nuclear matter — protons and neutrons, and their constituent quarks — interact under the extreme conditions found in neutron stars.
The European Space Agency released the most accurate and detailed map of the oldest light in the Universe. The radiation originally formed about 380,000 years after the Big Bang, when all matter was created some 13.82 billion years ago.
The images, released on Thursday (March 21 2013), suggest that at 13.84 billion years the universe is older than previously thought - albeit by only 48 million years.
They also suggest it contains slightly more matter than expected and a little less “dark energy”, the mysterious force which is believed to drive the expansion of the universe.
Although the measurements made by Planck match the theoretical predictions of what the Universe should look like, there are some important differences, such as a notable asymmetry between the opposite hemispheres of the sky and a “cold spot” that extends over a much larger patch of the sky than expected.
“The fact that Planck has made such a significant detection of these anomalies erases any doubts about their reality; it can no longer be said that they are artefacts of the measurements. They are real and we have to look for a credible explanation,” said Paolo Natoli of Ferrara University in Italy.
The gravitational field surrounding this massive cluster of galaxies, Abell 68, acts as a natural lens in space to brighten and magnify the light coming from very distant background galaxies.
In this photo, the image of a spiral galaxy at upper left has been stretched and mirrored into a shape similar to that of a simulated alien from the classic 1970s computer game “Space Invaders!” A second, less distorted image of the same galaxy appears to the left of the large, bright elliptical galaxy.