Archive for the ‘Universe’ Category

A favourite book of mine is Arthur C. Clarke’s 2001: A Space Odyssey.  This is a wonderful and epic tale of human first-contact with an ancient extra-terrestrial race.  I must point out at this juncture, however, that I actually saw the Kubrick film before I read the book; in fact it was the film that spurred me onto reading the book and, indeed, the whole series.

For me, both the book and the film are wonderful examples of that ultimate mystery and intrigue that taps into the archetypal well shared by (most of) humanity: what lies beyond our cosmic shores? But more importantly, who?

I’m a keen advocate of other life existing out there, somewhere in the Universe.  I don’t think that it’s a massive leap of faith to believe this in the same way that some might believe in a God.  We have the definitive proof that life is likely to exist – us!  We exist, we are alive and we have followed a cosmic evolutionary path for billions of years to reach this point.  We are surrounded by life-forms that have evolved in some of the most extreme places on Earth, some of them more alien than even the most creative special effects wizards could imagine.

The Earth is the only inhabited planet in a solar system of eight, orbiting our star (I still miss Pluto).  It is thought that there are between 200 and 400 billion stars in our galaxy alone, and an estimated 100 billion galaxies in the observable Universe (maybe more).  As well as this, the Universe itself is 13.7 billion years old.  We can’t possibly be the only ones, can we?

We know that there are other planets that lie outside of our solar system.  In the last month, scientists discovered a planet that lies within the so-called “Goldilocks Zone” around a Sun-like star called Tau Ceti.  The planet, thought to be between two to six times bigger than the Earth, is circling its star in an orbital region that is “neither too hot nor too cold to allow liquid surface water and, potentially, life”; similar to the orbital region that Earth inhabits.  This discovery and the plethora of other planets discovered by scientists and members of the public alike, show how common these extra-solar systems are.  Scientists even go so far as to predict that practically every star in our galaxy could have multiple planets orbiting them, many of which, potentially habitable.

Astounding stuff, don’t you think?  Real, potential life, beyond the ‘Pale Blue Dot’; it’s the stuff of dreams.  Problem is, we can’t really say for sure that they are inhabited.  We don’t know if life exists there because we can’t actually see the planets.

We know that they are there and we know, roughly, their size, simply by observing the effect that they have on their parent stars.  But, sadly, despite our wondrous advancement, the technology is many years away from reaching a sophistication whereby we could actually physically observe them.  Could we visit?  Not anytime soon.  Despite being a mere 12 light years away, Tau Ceti is still much too far for any possible human mission at our current stage of space travel.

Fear not, though, young space-farers.  Our journey to an extra-terrestrial domain may be sooner, and closer, than you think.

The title of this blog refers to the last words the fictional astronaut Dave Bowman speaks before he disappears into the monolith/star gate at the end of 2001: A Space Odyssey.  It is an inspiring and breath-taking moment.  As he travels through to an unknown star system, he sees the remnants of ancient civilisations and bizarre objects that appear to be life-forms, travelling across the surfaces of a binary star system “like salmon moving upstream”.

In the second instalment of the series, 2010: Odyssey II, there is a further moment of wonder, when the ancient aliens relay a message to all humankind:

“ALL THESE WORLDS ARE YOURS – EXCEPT EUROPA.  ATTEMPT NO LANDINGS THERE.”

The reason behind this explicit instruction is that the aliens have discovered primitive, aquatic life-forms living in the liquid water beneath the icy surface of this Jovian moon; and they deem this life to have evolutionary potential.

But this is a work of fiction, surely?  How can this have any relevance to the actual discovery of extra-terrestrial life?

Well, the possibility of life existing on the Jovian moon of Europa may be a little nearer to the truth than you might imagine.

In fact, scientists now think that several moons within our solar system could have the potential for life: the moons Europa, Ganymede and Callisto that orbit Jupiter; and the moons Titan and Enceladus that orbit Saturn.

These moons all have subsurface oceans, each of which may contain more water than is found in all of the oceans on Earth, with depths that are ten times greater than the deepest ocean: and the belief is that these oceans could harbour life.  Perhaps not the enormous, alien-dinosaur creatures that may immediately swim out of your imagination; but maybe this life could be plant-like, maybe simple and microbial, maybe resembling insects, crustaceans, cephalopods; maybe there’s nothing there.  Who knows?  But within a vast, liquid water ocean, tidally heated and left to ferment and brew for billions of years, the possibilities are breath-taking.

Moreover, these worlds are within our reach.  Enceladus is one billion miles away, Europa, just half that distance, so compared to Tau Ceti’s twelve light years, they’re practically just around the corner.

And go we shall.  The European Space Agency has a planned mission to explore the icy moons of Jupiter.  The Jupiter Icy moons Explorer (JUICE) will make a grand tour of the three Jovian moons and take samples for study.  We may have to wait a while for the incontrovertible proof that we might not be alone, as JUICE doesn’t launch until 2022 and won’t arrive at Jupiter until 2030, but provided we are all still around by then it should offer us invaluable insights into “what are the conditions for planet formation and the emergence of life, and how does the Solar System work?”

There can be little doubt that life is a wonderful and astonishing thing, but is it unique to this dark and insignificant corner of one galaxy, or is it ubiquitous throughout the cosmos.

The author of the Odyssey series Arthur C. Clarke once said: “Two possibilities exist: either we are alone in the Universe or we are not. Both are equally terrifying.”  I would certainly find the latter equally exhilarating.

John

Sources: http://news.discovery.com/space/extraterrestrial-oceans-may-offer-best-chance-for-finding-genesis-ii-121227.html

http://www.independent.co.uk/news/science/scientists-find-habitable-tau-ceti-planet-8424912.html

http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=50321

These last few weeks has heralded the welcome return of a dear old friend, and on Guy Fawkes evening I finally got the chance to see him for the first time this year.  As the wispy spectres of dying bonfires hung low in the autumn air, the cold, crisp, cloudless night sky was unveiled in all of its grandeur, and there, standing valiant on the south-western arc of the celestial equator was Orion.

The hunter: his club held high in his right hand, a lion’s skin draped on his left.  Flanked by his hunting dogs Canis Major and Canis Minor he traverses the skies, perpetually battling the charging bull, Taurus (or relentlessly pursuing Lepus the hare, depending on your reading of the myth).

Image   Orion is, by far, the most recognisable constellation in the night sky.  Unlike most of the other constellations, it doesn’t take the amateur stargazer several moments to link point-of-light to point-of-light to uncover the form and shape; he stands out from the others with striking clarity.  The stars Alnitak, Alnilam and Mintaka form his almost horizontal belt.  His sword is the home of a beautiful nebula. Upon his feet he wears the stars Rigel and Saiph, and his shoulders carry the stars Bellatrix and Betelgeuse.

Betelgeuse is a star of particular interest.  If you were to look at Betelgeuse through a telescope or even with the naked eye you would notice one thing: its colour.  Betelgeuse is red.  It is red because of the type of star that it is: a red supergiant.

Betelgeuse is around twenty times the mass of our Sun, and if it was to replace the Sun at the centre of our Solar System, it would extend out to Jupiter, engulfing us and everything else in its wake.

The other thing of note about Betelgeuse is that it is dying.  This unimaginably vast and beautiful star is entering the final stages of its life.  At only 10 million years old it is still a relatively young star (compared to our sun, which is nearly 5 billion years old with another 5 billion to go), but because of its immense size it has sped through its life.  And when it goes, it will not go quietly.  Betelgeuse will shuffle off this mortal coil as a supernova.  And because it is only around 500 light years away it will present us with quite a show.Image

When Betelgeuse goes supernova, it will shine in our skies as bright as the moon and will probably be visible during the day (although not in a Tatooine binary sun way).  In that single instance of stellar explosion, Betelgeuse will release more energy than our sun will produce in its entire lifetime.  This display will remain in our skies for approximately 2-3 months before dimming.

So, when will this happen?  Well, by current estimations, anytime soon.  But when is ‘soon’?  Well, soon could be anytime from tomorrow morning to the next million years.  Betelgeuse is ready to blow!  However, stellar time scales do not take into account human impatience, or human lifetimes, or even human existence.  Also, let’s not forget that, if tomorrow is S-Day (Supernova) for Betelgeuse, we won’t see the resulting spectacle until sometime around the 25th century due to the distance of the star and the speed of light.  So unless the event happened in and around the 16th century, we might be in for a bit of a wait.

The last supernova visible from Earth occurred in 1604, before the invention of the astronomical telescope.  We should also, theoretically, get at least one supernova per galaxy per century.  But we’ve not had the good fortune to witness such a spectacle on terra firma for over 400 years.

There is another reason why there is great importance in the death of Betelgeuse, or any other star in its final throes, or, for that matter, any other star in the Universe.  They are the origins of life; we were forged in the hearts of dying stars.

Stars, such as our Sun, are fuelled through the nuclear fusion of hydrogen into helium, which releases vast amounts of energy allowing the star to generate heat and light.  As the star reaches its twilight years and begins to run out of its hydrogen fuel, the battle between nuclear fusion and gravity begins to give way in favour of gravity.  The star then begins to collapse in on itself.  As this happens, the star becomes an alchemist.  Within the increasing heat and density of the collapsing star, nuclear fusion goes beyond simple hydrogen to helium combinations.  More complex atoms begin to fuse together, including carbon and oxygen and many more.  When the star finally gives in to its cataclysmic death, these elements are then violently distributed throughout the universe, forming clouds of dust and gas, clumps of rock, planets, organic material; us.

All living and non-living things with mass are made up of a variety of atoms, and those atoms were forged within the fiery hearts of dying stars.  We are stardust!  It’s a very hippy thing to say, but it’s true.  Although, I think that theoretical physicist Lawrence Krauss said it better:

“Forget Jesus!  The stars died so that you could be here today!”

Ever since I was a little biddy boy I have loved the stars, the planets, the universe, and I have always greeted the appearance of Orion with joy.  Orion arrived with the falling of the leaves, the snow and with Christmas; what better friend for a kid!

What better friend for a Universe that has the potential to harbour life than a star that, after eons of lighting up the cosmos, makes the ultimate sacrifice in order to fill the void with the materials for creation.

So next time you see Orion, look at the red twinkle on his right shoulder and give a dying old man a smile.

John