Space

Stars and galaxies formed back in the early days of the universe,  some 13 billion years ago, were not nearly as massive as originally thought. Population III stars were not only smaller than believed, they actually formed in binary systems, that is, pairs of stars that orbit a common center, say the results of a new simulation. "For a long time the common wisdom was that these Population III stars formed alone," said Brian O'Shea, a Michigan State University assistant professor of physics and astronomy  who did the research with two colleagues. "Researchers also have believed…

Johann Galle fans won't like reading this but professor David Jamieson, Head of the School of Physics at the University of Melbourne, says Galileo beat him to the punch in the discovery of Neptune - by 234 years. If correct, the discovery would be the first new planet identified by humanity since deep antiquity. Jamieson is investigating the notebooks of Galileo from 400 years ago and says that buried in the notations is the evidence that he discovered a new planet that we now know as Neptune, which was 'first' observed Sept 23, 1846 by Johann Galle at the Berlin Observatory..  Jamieson'…

A team of astrophysicists say they have solved a mystery that led some scientists to speculate that the distribution of certain gamma rays in our Milky Way galaxy was evidence for undetectable 'dark matter' making up much of the mass of the universe. In two papers, the astrophysicists instead say that this distribution of gamma rays can be explained by the way "antimatter positrons" from the radioactive decay of elements, created by massive star explosions in the galaxy, propagate through the galaxy. Thus, they say, the observed distribution of gamma rays is not evidence for dark matter. "…

The Swan Nebula, also called the Omega Nebula because when seen through a small telescope the nebula has a shape that reminds some observers of the final letter of the Greek alphabet, omega, while others see a swan with its distinctive long, curved neck, is a dazzling stellar nursery located about 5500 light-years away towards the constellation of Sagittarius (the Archer). Don't feel left out, lawn games and crustaceans, it is also called  the Horseshoe and the Lobster Nebula. No matter its name, it is an active star-forming region of gas and dust about 15 light-years across and has…

Even among giants Messier 87, with two to three billion times the mass of our sun, stands out, completely dominating the Virgo cluster. A supermassive black hole exists in the center of Messier 87 and gigantic plasma flows shoot out from the vicinity of the black hole at close to light speed. Scientists have now observed, simultaneously in gamma and radio frequencies, this active galactic core region and in doing so discovered that the elementary particles are accelerated to extremely high energy levels in closest proximity to the black hole. Messier 87 is a giant elliptical radio galaxy in…

Two studies published in Science Express show the analysis of gamma-rays from two dozen pulsars, including 16 discovered by  NASA's Fermi Gamma-ray Space Telescope. Fermi is the first spacecraft able to identify pulsars by their gamma-ray emissions alone. A pulsar is the rapidly spinning and highly magnetized core left behind when a massive star explodes. Most of the currently cataloged pulsars, some 1800 of them, were found through their periodic radio emissions; pulses caused by narrow, lighthouse-like radio beams emanating from the pulsar's magnetic poles, according to current theory…

Astronomers have unveiled a new atlas of the inner regions of the Milky Way - that's our home galaxy, if you're from someplace else - and it's peppered with thousands of previously undiscovered dense knots of cold cosmic dust, the potential birthplaces of new stars. Using observations from the APEX telescope in Chile, this survey is the largest map of cold dust so far. This new guide for astronomers, known as the APEX Telescope Large Area Survey of the Galaxy (ATLASGAL) shows the Milky Way in submillimetre-wavelength light (between infrared light and radio waves. Images of the cosmos at these…

NASA's Lunar Reconnaissance Orbiter has transmitted its first images since reaching the moon on June 23. The spacecraft's two cameras, collectively known as the Lunar Reconnaissance Orbiter Camera, or LROC, were activated June 30. The cameras are working well and have returned images of a region in the lunar highlands south of Mare Nubium (Sea of Clouds). As the moon rotates beneath LRO, LROC gradually will build up photographic maps of the lunar surface. These images show cratered regions near the moon's Mare Nubium region, as photographed by the Lunar Reconnaissance Orbiter's LROC…

Astronomers using ESA’s XMM-Newton X-ray observatory have discovered a black hole they labeled HLX-1 (Hyper-Luminous X-ray source 1), which lies towards the outskirts of the galaxy ESO 243-49, approximately 290 million light-years from Earth and weighs more than 500 solar masses, making it a 'missing link' between lighter stellar-mass and heavier supermassive black holes. This discovery is the best detection to date of a new class that has long been searched for: intermediate mass black holes. The discovery has been made by an international team of researchers working with XMM-Newton…

Why did our Milky Way galaxy survive while others failed?    Ill-defined, convenient catch-all dark matter gets the credit, according to a new paper.   Dark matter is thought to make up 85 per cent of the Universe’s mass and it may also be one of the building blocks of galaxy formation. The researchers say that the early Milky Way, which had begun forming stars, held on to the raw gaseous material from which further stars would be made. This material would otherwise have been evaporated by the high temperatures generated by the “ignition” of the Universe about half-a-billion…