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http://www.bbc.co.uk/news/science-environment-29168676 The Advanced Ligo instrument, a laser "ruler" built to measure the traces of gravitational waves, is progressing at amazing speed, scientists say. The first generation of Ligo, which ran between 2001 and 2010, saw nothing. Over the last four years scientists have designed a more sensitive detector that achieved "full lock" in June this year, earlier than planned. Researchers reported that the new one is already 30% more precise and will start scanning the sky in summer 2015. Ligo (Laser Interferometer Gravitational-Wave Observatory) operates in two sites in the US, one in Livingston, Louisiana, and another one in Hanford, Washington. Space ripples "In June we reached this state that we call 'locking', where the entire system is switched on and behaves for a short time, 10 minutes or so, as predicted it should do in science mode," said Prof Andreas Freise from the school of physics and astronomy of the University of Birmingham during the British Science Festival. Gravitational waves are ripples in the fabric of space and time that propagate across the Universe like sound waves do after an earthquake. But in this case, the sources of the "tremors" are very energetic events such as supernovas (the explosion of a dying star), fast spinning neutron stars (very dense and compact stars), or the collision of black holes and neutron stars orbiting close to each other. With Ligo's current precision, the interferometer should be able to detect gravitational waves coming from neutron star and black hole binary systems 27 megaparsecs (about 88 million light-years) away from us. Researchers are still working on the intricate optical system and detectors within Advanced Ligo to gradually increase the precision. "The target is to reach [a distance of] 200 megaparsecs… which is a factor of 10 better than the old detector," explained Prof Freise. Gravitational waves are thought to emerge from energetic events such as the collision of two neutron stars Augmenting the distance by a factor of 10 means that Ligo will scan a volume of space 1,000 times larger than before. "Advanced Ligo will be sensitive to a factor of 1,000 in the volume that we were observing with initial Ligo, and that is the sphere of volume where we expect to see a few gravitational waves," added Prof Alberto Vecchio also from the School of Physics and Astronomy of the University of Birmingham. Ligo observatories operate by beaming a high power laser into a splitter that divides the beam into two parts. Each part is then directed towards two 4km tunnels perpendicular to each other. A mirror at the end of the tunnels reflects the rays back into a detector where they are recombined. Since both tunnels are equally long, when the two halves meet in the detector the signal shows no pattern. But this is not the case if a gravitational wave were passing through the Earth. "When [the gravitational waves] reach Earth they distort space and time. In particular, they will change the separation of the mirrors," explained Prof Vecchio. "Over 4km, a decent gravitational wave that we can detect creates a change of less than a thousandth of the size of the nucleus of an atom." This minuscule variation in the space between the mirrors will produce a distinct pattern from which the properties of the gravitational waves can be inferred. Profound observation The team at the University of Birmingham has been involved in Ligo since 2000, leading the development of technology and hardware, and the tools for the analysis of the scientific data. The main improvements in Advanced Ligo included an upgraded suspension system of the mirrors to make them as stable as possible, a more powerful laser, and a change in the optical elements to accommodate the laser's extra power. Although the former Ligo instruments did not detect any signature in its 10 years of observation, researchers think that with the upgrade, Advanced Ligo will be able to detect at least one gravitational wave in its lifetime. Prof Vecchio said that the most pessimistic prediction is that "Ligo will deliver one detection over five years". "Reasonable predictions tell you many events per year and there are optimistic ones that tell you a hundred or a thousand. We just don't know." Ligo will complement rather than compete with the results of the Bicep2 and Planck experiments, as it is tuned to look at much shorter wavelengths. The implications of detecting gravity waves are profound from a scientific point of view. Prof Freise said: "There are two aspects. One is testing the theory of gravity, but I think the more interesting for me is for astronomy. "We are tapping into the unknown here, so we will get a new signal that may tell a lot of people in astronomy that they were wrong. And that's what I am after. Red text is my highlighting Call me cynical but most builders struggle to build a house to exactly the dimensions shown on a plan and these guys have built two 4km (2.4855 miles give or take ) perpendicular tunnels so that both are exactly the same length??

http://www.youtube.com/watch?v=XqMlo51U_KQ http://www.youtube.com/watch?v=aj1kkK_1JPo http://www.youtube.com/watch?v=KEvYlO6DrAc the rest are available on his channel

First off, welcome to this thread. Next I am working on building a survival kit that MacGyver would have been proud of. Feel free to post your ideas on what I can add to this and then I will update the Master List in the bottom of this post. The plan is to make it as small as possible, perhaps to fit inside a Waterproof Box, like this. I won't list all of the items I have included so far so as to give you guys a change to post your own ideas. Just post up a Picture when you make an addition. Sort of like a forum game. Also, you can post up any Science type videos that MacGyver would proud of. The plan is to have a survival kit with links to all kinds of things you would be able to do with the kit included in it. Like this for example. How to cut a glass bottle, clean in half As we find new and interesting science experiments, we'll add the necessary items. Also, if you have some random knowledge, chime in like this. "Did you know, banging a metal pipe on metal causes temporary molecular structural alignment as all the ions run to the other end thereby creating the magnet" MASTER LIST Waterproof Box Yarn, 10 ft length Multi-Tool 2 AA batteries 1 9 V battery 1 12 V a23 battery 5 sticks of chewing gum Tin Can with top cut off (store additional survival items inside to save space) Rubber Band Sewing Needle - and kit Wire, Insulated, Copper - 24" Candle Wick Superglue tube Safety Pins Swivels, Fishing Toothpick Trick B-Day candle Valve Stem Cap remover Lip Balm Tube (store emergency money in) Ball Point Pen (parts - plastic tube, spring, ink) Dental Floss (cordage, dental care) Emergency Can Opener Pencil Sharpener Carpenter Pencil Heat Shrink Tubing Zipties Ductape Scissors (sewing kit) 6 color roll of thread Razor Blade 6" length of medical tubing (tracheostomy, use as straw, nasopharyngeal airway) Clothes pin Alligator clips Caribiner (use to attach box to pack on outside) Velcro strips, 6 " Pocket Socket Wrench, Survival tool Field Fix it kit Rubber repair kit Mini button compass Mini survival mirror Survival Finger Saw Mini bobber (fishing) Band-aids Cordage, fishing line, 20 ft Cordage, jute twine, 6 ft Cordage, nylon, 6 ft Handcuff key MASTER LIST - DID YOU KNOW Magnetism "Did you know, banging a metal pipe on metal causes temporary molecular structural alignment as all the ions run to the other end thereby creating the magnet" ...You can magnetize a needle to make a compass Light You can insert a candle wick into a can of tuna in oil to make an oil lamp Physics ...you can use a rubber band to open a door locked by a sliding chain, from the outside. Attach one end to the chain and the other end to the door knob. Open the door and it will slide the chain off. Fire ...you can use a piece of chewing gum foil to start a fire. Just fold up the foil and attach each end to opposite ends on the battery. The current flowing through will ignite the wrapper. ...you can start a fire by touching a 9v battery to steel wool.

Warning : dont watch the video if you are eating. seriously dont. it is nasty. Also, have the sound turned on for full effect youtube makes you sign in to confirm your age, so use the link http://www.iflscience.com/plants-and-animals/caution-dead-whale-contents-under-pressure http://youtu.be/dCsMNurn3bQ

Continuing my old thread The Body-Mind Relation The Sense of Fear to be continued...