Astronomy with a Gravitational Slant
Visible light, like the kind picked up by telescopes is part of the Electro-magnetic spectrum. This light which travels millions of light years until it hits our eyes (or telescopes) has been the basis of the entire history of astronomy. But now in the 21st century, scientists are on the verge of what is hailed to become the greatest discovery of our age.
This discovery will (hopefully) be made through the use of devices called Laser Interferometers that have been designed in an effort to detect gravitational waves. So What? Well there are massive implications from detecting gravitational waves; for starters their successful detection will be a further confirmation of Einstein’s general theory of relativity. Secondly, it will open up a whole new kind of astronomy. Most of the universe does not emit Electro-magnetic waves (e.g. light) so at present we are unable to study them. The success of this new technology will allow us to study cosmic objects without the need to rely on light, meaning scientist will be able to look inside the most violent events in the universe.
These ripples in space-time are extremely weak making them almost impossible to detect so Astro-boffins from NASA and Academia have had to develop fantastically accurate equipment in order to try and detect them.
Like me, you’re probably thinking Gravity’s weak? I thought it was holding everything including us tethered to the Earth’s surface. Well yes it is, but in relation to other forces at work in the Universe it is incredibly weak. You can prove this to yourself right now; all you need is a magnet and a sewing pin.
Place the pin on the table and hover the magnet over it until it lifts the pin right off the table. Now that insignificant magnet managed to attract that pin out of gravity’s clasp despite the fact that the entire Earth was pulling on it!
So to detect waves of Gravity from the depths of space is pretty tricky, the set-ups produced in Europe and the US have shoot Lasers down vacuum that are between 0.5 and 4 KM long. At the end of the tubes are finely crafted mirrors hung from dampened glass threads. Professor Karsten Danzmann, from the Albert Einstein Institute and Hanover University stated:
"The displacement sensitivity of GEO 600 is one three-thousandth of the diameter of a proton,"
Sounds pretty damn fine, but what’s that in layman’s terms Professor D?
"Put another way, it's equivalent to measuring a change of one hydrogen atom diameter in the distance from the Earth to the Sun."
So from this mind-boggling analogy you can really see how tricky this detecting gravity waves business is. But not to worry, the boffins have everything ready and both the US and European systems are due to begin a full science run this month, in which they will continuously detect data for 18 months. If a wave is detected by at least two the sites, then the results will be official.
There are even grander plans to launch one of these facilities into space with 3 spacecraft flying in formation 5 million km apart. Calculation’s show that this project, LISA (Laser Interferometer Space Antenna) could detect left over gravitational radiation from the big bang, hopefully settling some of those arguments plaguing the big thinkers on the forefront of theoretical physics. Professor Mike Cruise from Birmingham University remarked
"Some of these observations are going to give us a clue as to how gravity can be viewed in terms of quantum mechanics and the prospect of that is just mind-boggling."
Well you said it man, and you’re the professor! Personally I’m eagerly awaiting the results from this just so that I can hear about what crazy theory’s and explanations will be cooked up.
That’s all for today, but be sure to pop back over the weekend for the first instalment of real men of genius.