Saturday 13 February 2016

Solar Sails, Ripples in Spacetime, and Holidays on Distant Moons




Of course, the big news this week is the proof of the existence of Gravitational Waves .
The dedicated team at LIGO made the announcement on Thursday, 11th Feb.
Some of those involved have made the search their lifes work , and the initial team was assembled back in 1975.
It brings to a conclusion the decades of speculation (and false signals), and the vindication of Albert Einsteins prediction , over a hundred years ago.
It also tells us that 'spacetime' is flexible, and not rigid, as a medium: this will fuel all manner of sci-fi conjecture.
This is a truly amazing revelation , which will lead to game - changing discoveries.
It enables us to better understand gravity, but also opens a whole new realm of exploration.
In essence, visual wavelengths have been used to observe stellar phenomenon - but this discovery brings the dimension of sound into play.
The initial sound of the  two black holes merging which led to this discovery has already been timestretched into an ambient, hour - long piece - it is essentially a rising scale on a cosmic keyboard up to middle C - (maaan).
The number crunching is mind blowing in itself - the gravitational wave began with two black holes colliding 1.3 billion years ago, unleashing an energy equivalent to the observable universe x50 - but which ultimately only affected the measuring devices by one ten thousandth the width of the nucleus of an atom.
Cue my mind melting.
We are dealing with next level science here, way beyond my own ability to fathom : infact, it's so far out, that I found myself drawn to the human element of the story - Dr Ron Drever, one of the earliest members of the team, could not join in the celebrations as he is now in a nursing home in Edinburgh, suffering with dementia.
His colleague, Dr  Rainer Weiss maintains that it was Dr Drevers creative genius that helped to propel the discovery.

Planetary Society LightSail


Solar Sails

In the last post, I extolled the virtues of nuclear fusion, and have decided to redress the balance by writing up solar sails, which are unrivalled as a means of distance travel through deep space .
I don't want to get bogged down in the arguments for and against , but certainly in terms of deep space, the solar sail has the edge.
Although the force employed (photons) is very small, the push is continuous, so the acceleration is constant.
It's been estimated that a craft with a 1300 foot sail could travel 1.3 billion miles a year, and leave our solar system within ten years
The only real issue for deep space travel would be the need for a huge laser firing photons at the sail, in lieu of sunlight.
In 2010, the Japanese craft Ikaros employed a solar sail 46 feet wide, and recently (albeit with limited success) the Planetary Society unfurled a larger sail.
The sheer scale of the sails required for interstellar journeys is incredible, and would create quite a visual impact in the darkness of space.
Attempts to guess the fastest method of travel to the nearest star (Proxima Centauri) give us a possible 9 years using a massive solar sail (600 miles / 945 km diameter) .
Nine years travel may sound a lot , but Proxima Centauri is 4 light years distant, so 9 years is actually pretty fast - well, unless you compare it to your daily commute.
Quite apart from the sheer scale of the thing, it would need boosting from a giant laser once it leaves the area of influence of our sun, so for now at least, this is in the realms of sci-fi.


©NASA
In Other News...

NASA have released a series of retro 'travel' posters extolling the virtues of 'space breaks'- if you were uncertain as to choosing a holiday on Enceladus as opposed to Titan, for instance.
I think they are great, although my past playthroughs of the computer game ' Bioshock ' gives  me reservations about such Art Deco styling.


Bioshock

Apparently, an asteroid heading our way on March 5th could fly past Earth at a distance of 11,000 miles, which is a mere whisker (in cosmic terms).
The comet in question ( designated 2013 TX68 ) - was only discovered three years ago, and as such, has no given name.
There is a one in 250 million chance of impact, hardly enough to cause sleepless nights - but then, what about the comets we didn't discover yet ?
Goodnight