New look for the Milky Way

Our galaxy is no run-of-the-mill spiral galaxy. Instead, the Milky Way has a long central bar running across its nucleus-the spherical bulge of stars at its centre-say astrophysicists at the University of Wisconsin-Whitewater. Using NASA’s Spitzer Space Telescope, the researchers surveyed the positions of about 30 million stars at the centre of the galaxy. Since the Spitzer probe captures images in infrared, it was able to cut through the clouds of interstellar gas and dust that make optical observations difficult. Our galaxy’s central bar, the scientists found, is 27,000 light years in length, and contains mostly old and red stars. Astrophysicists have long debated whether the Milky Way’s centre featured a bar-like structure or an ellipse.

Source: Astrophysical Journal Letters

Now the space forecast

Unpredictable space weather phenomena may well doom manned missions to Mars, warns University of Warwick researcher Dr. Claire Foullon. She is particularly concerned about Solar Proton Events (SPEs), during which the sun ejects massive clouds of material from its surrounding corona. SPEs bathe the inner Solar System with dangerous high-energy charged particles. One of the largest such events on record, in 1972, would have delivered a deadly dose of radiation to Apollo astronauts in just ten hours. Foullon recommends deploying a small fleet of satellites to provide space weather warnings to future Mars-bound missions.

Source: Space Weather

Cosmic baby-boomers

The early universe was a much more hospitable place for galaxies to form than previously thought, report scientists at the European Space Observatory’s Very Large Telescope (VLT), based in Chile. They used the VLT to measure how quickly distant galaxies are receding from our own-known as red shifts. The more distant a galaxy is, the faster it recedes from our own, and the greater its red shift. By examining a patch of sky known to contain 8,000 galaxies, the ESO scientists determined that almost 1,000 of them have red shifts dating their birth to an era between 1.5 billion and 4.5 billion years after the Big Bang (circled in above photo). They also found these young galaxies were prodigious stellar nurseries, producing many more stars each year than newer galaxies such as our own.

Source: Nature