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Archive for March 25, 2013

Black Hole-Star Pair Orbiting At Dizzying Speed


ESA’s XMM-Newton space telescope has helped to identify a star and a black hole that orbit each other at the dizzying rate of once every 2.4 hours, smashing the previous record by nearly an hour.

The black hole in this compact pairing, known as MAXI J1659-152, is at least three times more massive than the Sun, while its red dwarf companion star has a mass only 20% that of the Sun. The pair is separated by roughly a million kilometres.

The duo were discovered on 25 September 2010 by NASA’s Swift space telescope and were initially thought to be a gamma-ray burst. Later that day, Japan’s MAXI telescope on the International Space Station found a bright X-ray source at the same place.

The black hole and the star orbit their common centre of mass. Because the star is the lighter object, it lies further from this point and has to travel around its larger orbit at a breakneck speed of two million kilometres per hour – it is the fastest moving star ever seen in an X-ray binary system. On the other hand, the black hole orbits at ‘only’ 150 000 km/h.

Full Story: http://www.esa.int/Our_Activities/Space_Science/Black_hole-star_pair_orbiting_at_dizzying_speed

Herschel Discovers Some Of The Youngest Stars Ever Seen


Astronomers have found some of the youngest stars ever seen, thanks to the Herschel space observatory, a European Space Agency mission with important NASA contributions.

Observations from NASA’s Spitzer Space Telescope and the Atacama Pathfinder Experiment (APEX) telescope in Chile, a collaboration involving the Max Planck Institute for Radio Astronomy in Germany, the Onsala Space Observatory in Sweden, and the European Southern Observatory in Germany, contributed to the findings.

Dense envelopes of gas and dust surround the fledging stars known as protostars, making their detection difficult. The 15 newly observed protostars turned up by surprise in a survey of the biggest site of star formation near our solar system, located in the constellation Orion. The discovery gives scientists a peek into one of the earliest and least understood phases of star formation.

“Herschel has revealed the largest ensemble of such young stars in a single star-forming region,” said Amelia Stutz, lead author of a paper to be published in The Astrophysical Journal and a postdoctoral researcher at the Max Planck Institute for Astronomy in Heidelberg, Germany. “With these results, we are getting closer to witnessing the moment when a star begins to form.”

Full Story: http://www.jpl.nasa.gov/news/news.php?release=2013-102

Voyager 1 Has Entered A New Region Of Space, Sudden Changes In Cosmic Rays Indicate


Thirty-five years after its launch, Voyager 1 appears to have travelled beyond the influence of the Sun and exited the heliosphere, according to a new study appearing online today (March 20).

The heliosphere is a region of space dominated by the Sun and its wind of energetic particles, and which is thought to be enclosed, bubble-like, in the surrounding interstellar medium of gas and dust that pervades the Milky Way galaxy.

On August 25, 2012, NASA’s Voyager 1 spacecraft measured drastic changes in radiation levels, more than 11 billion miles from the Sun. Anomalous cosmic rays, which are cosmic rays trapped in the outer heliosphere, all but vanished, dropping to less than 1 percent of previous amounts. At the same time, galactic cosmic rays – cosmic radiation from outside of the solar system – spiked to levels not seen since Voyager’s launch, with intensities as much as twice previous levels.

Full Story: http://www.agu.org/news/press/pr_archives/2013/2013-11.shtml
Also: http://www.jpl.nasa.gov/news/news.php?release=2013-107

Planck Mission Brings Universe Into Sharp Focus


Image credit: ESA and the Planck Collaboration

Image credit: ESA and the Planck Collaboration

The Planck space mission has released the most accurate and detailed map ever made of the oldest light in the universe, revealing new information about its age, contents and origins.

Planck is a European Space Agency mission. NASA contributed mission-enabling technology for both of Planck’s science instruments, and U.S., European and Canadian scientists work together to analyze the Planck data.

The map results suggest the universe is expanding more slowly than scientists thought, and is 13.8 billion years old, 100 million years older than previous estimates. The data also show there is less dark energy and more matter, both normal and dark matter, in the universe than previously known. Dark matter is an invisible substance that can only be seen through the effects of its gravity, while dark energy is pushing our universe apart. The nature of both remains mysterious.

“Astronomers worldwide have been on the edge of their seats waiting for this map,” said Joan Centrella, Planck program scientist at NASA Headquarters in Washington. “These measurements are profoundly important to many areas of science, as well as future space missions. We are so pleased to have worked with the European Space Agency on such a historic endeavor.”

Full Story: http://www.jpl.nasa.gov/news/news.php?release=2013-109
Also: http://www.bis.gov.uk/ukspaceagency/news-and-events/2013/Mar/planck-challenges-our-understanding-of-the-universe
Also: http://www.esa.int/Our_Activities/Space_Science/Planck/Planck_reveals_an_almost_perfect_Universe
Also: http://www.jpl.nasa.gov/news/news.php?release=2013-110
Also: http://www.ia.ucsb.edu/pa/display.aspx?pkey=2967
Also: http://www.princeton.edu/main/news/archive/S36/38/99C85/