WASHINGTON - Radio astronomers have uncovered 17 millisecond pulsars in our galaxy by studying unknown high-energy sources detected by NASA's Fermi Gamma-ray Space Telescope. The astronomers made the discovery in less than three months. Such a jump in the pace of locating these hard-to-find objects holds the promise of using them as a kind of "Galactic GPS" to detect gravitational waves passing near Earth.

A pulsar is the rapidly spinning and highly magnetized core left behind when a massive star explodes. Because only rotation powers their intense gamma-ray, radio and particle emissions, pulsars gradually slow as they age. But the oldest pulsars spin hundreds of times per second - faster than a kitchen blender. These millisecond pulsars have been spun up and rejuvenated by accreting matter from a companion star.

"Radio astronomers discovered the first millisecond pulsar 28 years ago," said Paul Ray at the Naval Research Laboratory in Washington. "Locating them with all-sky radio surveys requires immense time and effort, and we've only found a total of about 60 in the disk of our galaxy since then. Fermi points us to specific targets. It's like having a treasure map."

Millisecond pulsars are nature's most precise clocks, with long-term, sub-microsecond stability that rivals human-made atomic clocks. Precise monitoring of timing changes in an all-sky array of millisecond pulsars may allow the first direct detection of gravitational waves - a long-sought consequence of Einstein's relativity theory.

"The Global Positioning System uses time-delay measurements among satellite clocks to determine where you are on Earth," explained Scott Ransom of the National Radio Astronomy Observatory in Charlottesville, Va. "Similarly, by monitoring timing changes in a constellation of suitable millisecond pulsars spread all over the sky, we may be able to detect the cumulative background of passing gravitational waves."

The sources Fermi detected are not associated with any known gamma-ray emitting objects and did not show evidence of pulsing behavior. However, scientists considered it likely that many of the unidentified sources would turn out to be pulsars.

For a more detailed look at radio wavelengths, Ray organized the Fermi Pulsar Search Consortium and recruited a handful of radio astronomers with expertise in using five of the world's largest radio telescopes - the National Radio Astronomy Observatory, Robert C. Byrd Green Bank Telescope in W.Va., the Parkes Observatory in Australia, the Nancay Radio Telescope in France, the Effelsberg Radio Telescope in Germany and the Arecibo Telescope in Puerto Rico.

After studying approximately 100 targets, and with a computationally intensive data analysis still under way, the discoveries have started to pour in.

"Other surveys took a decade to find as many of these pulsars as we have," said Ransom, who led one of the discovery groups. "Having Fermi tell us where to look is a huge advantage."

Four of the new objects are "black widow" pulsars, so called because radiation from the recycled pulsar is destroying the companion star that helped spin it up.

"Some of these stars are whittled down to masses equivalent to tens of Jupiters," said Ray. "We've doubled the known number of these systems in the galaxy's disk, and that will help us better understand how they evolve."

NASA's Fermi Gamma-ray Space Telescope is an astrophysics and particle physics partnership, developed in collaboration with the Department of Energy, along with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden, and the U.S. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

For images and animations related to this release, visit: http://www.nasa.gov/fermi

Source: NASA

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Surfing the web it becomes apparent that outdoor gear is indeed, a very important part of what outdoor enthusiasts look for; it also becomes apparent that outdoor apparel has become fashionable. That's okay, as long as the main point of getting gear and equipment is not missed: You don't guy gear to look cool, but to be more comfortable and safe.

Of course, we are free to purchase whatever we want, and if you are not a pilot you are still entitled to get a flight jacket if that's what you like; what would be bad is to believe that you are actually a pilot just because you bought that jacket, and while this example might sound a little bit outlandish or extreme, such things do happen, for example, when someone interested in mountain climbing but with relatively low experience buys climbing gear and attempts to use it in ways that go well-beyond his or her skill level believing that using such stuff depends just on buying it.

In the case of some outdoor or extreme activities people know where the limit are; for example, regular pilots generally know and assume that they should not get into the cockpit of a plane designed for aerobatics without proper training. That is so because the whole learning system in aviation is constructed on the basis of getting licenses to use increasingly complex aeronautical equipment. You can buy a plane all right, but you will not be able to use it if you don't get first the proper license. Something similar happens in the case of nautical activities and a few others, but there are many fields in which, while it may be discouraged to act without proper training, it is actually very easy to do so: If you have a brand-new plane sitting on the tarmac at your local airport, it would be hard to attempt to fly it without a license because airports are generally filled with people - even small ones - and someone in a position of authority will probably stop you, but who will take a look at what climbers or hikers or kayaking enthusiasts do?

Don't forget that the single, most important piece of equipment that you have is your own intelligence; if you are getting started in something like mountain biking, kayaking, climbing, etc. it is fundamental that you don't try to do more than you are capable of. Getting new gear is great, but sometimes it could lead to a false sensation of security when experience is somewhat lacking.

Source: Pablo Edronkin, Andinia.com

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Thanks to a satellite collar, two innovative scientists, and a blog, people can follow the travels of Brutus, the "North Pole wolf" as he leads his pack through the long arctic winter.

In July the scientists, one from the United States, the other from Canada, put the satellite collar on Brutus, the leader of his wolf pack, on remote Ellesmere Island, only 600 miles from the North Pole. Their goal - to finally find out what these "North Pole wolves" do in the long, dark days of winter in one of the harshest areas of the world.

"We first encountered 9-year-old Brutus back in 2003," said David Mech, a renowned U.S. Geological Survey (USGS) wolf researcher who has been studying the Ellesmere Island wolves for the last 24 years. That is, he's followed them during summer, which is pretty much the month of July. Snow begins falling in August, and except for June, that fleeting month of arctic spring, at most other times it is nearly impossible for people to travel to the island or withstand the cold temperatures.

"This year, we made a huge technological jump from notebook and pens to satellite collars because we wanted to find out what these arctic wolves do in winter in areas when it is dark 24 hours a day and temperatures can fall to -70 degrees Fahrenheit," Mech said. "How far must they travel to obtain enough food to make it to the Arctic spring, which doesn't happen until the next June?"

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Source: USGS

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