Monthly Archives: September 2015

ANDROMEDA… HAVE WE SEEN THE LIGHT?

andromeda_galaxy_400

At my Astronomy Society meeting the other week we had an expert talk to us about the Andromeda Galaxy. I also spoke to a woman who has witnessed a form of time travel but I’ll come to that later.

You can find the Andromeda galaxy as shown on the chart below. The constellation Cassiopeia appears in the north-east sky at nightfall and swings high to the north as evening progresses. It’s shaped like an M or W. Note that one half of the W is more deeply notched than the other half. This deeper V is your “arrow” in the sky, pointing to the Andromeda galaxy.

09nov18_430

On a dark night, this galaxy looks like a faint smudge of light and where there is light pollution from street lamps etc it may be difficult to see. Nevertheless, binoculars should show it clearly and are better than a telescope to find it as binoculars have a wider field of view. Just don’t expect it to look like the photo though, even with a telescope.

A galaxy is a gravitationally bound system of stars, stellar remnants, dust and gas and dark matter. The word galaxy is derived from the Greek, galaxias, literally “milky”, and our own galaxy is called the Milky Way. Galaxies range in size from dwarfs with just a few thousand stars to giants with one hundred trillion stars, each orbiting their galaxy’s own centre of mass.

There can be billions of suns in a galaxy and according to most estimates there are one hundred billion galaxies. Just try and assimilate those figures for a minute to see how many suns there may be. I shouldn’t try to multiply them together to get a total as you will run out of space on a calculator. Now, try and imagine that many of those suns (stars) may well have planets orbiting them and multiply that figure by the previous ones. Still with the total calculation? Yeah….right. It is almost infinitesimal.

Andromeda is a spiral galaxy and is the closest one to us. It is very similar to our own Milky Way  which you see high in the sky in the summer but it  is two and a half million light-years away, How could we ever get there?

Light travels at a constant speed in a vacuum; 186,000 miles per second. The Scottish physicist James Clerk Maxwell showed that when electric and magnetic fields change in time, they interact to produce a travelling electromagnetic wave. Maxwell calculated the speed of the wave from his equations and found it to be exactly the known speed of light. This reveals that light is an electromagnetic wave. In 1905,  Albert Einstein showed that c, the speed of light through a vacuum, is the universal speed limit. According to his special theory of relativity, nothing can move faster. He showed that the increased relativistic mass (m) of a body comes from the energy of motion of the body—that is, its kinetic energy (E)—divided by the speed of light squared (c2)   i.e. E = mc2

This means that you would have to travel at 186,000  miles a second for two and a half million years before you reached Andromeda. Of course such astronomical distances are impossible to breach, unless a new form of propulsion is found or we harness the potential time/space anomalies of black holes or wormholes.

In String Theory For Dummies, the authors (Andrew Zimmerman Jones and Daniel Robbins) explain that in physics, time travel is closely linked to Einstein’s theory of relativity, which allows motion in space to actually alter the flow of time. This effect is known as Time Dilation and was one of the earliest predictions of relativity. This sort of time travel is completely allowed by the known laws of physics, but it allows only travel into the future, not into the past.

Time dilation and black hole event horizons  provide intriguing ways of extending human life, and in science fiction they’ve long provided the means for allowing humans to live long enough to travel from star to star.

But when travelling at the speed of light there are other problems. Einstein’s equation indicates that time slows down when you reach the  speed of light and mass gets bigger. At another of our meetings a few months ago I spoke to a lady who had actually operated the Large Hadron Collider at CERN. She said that she had witnessed  this effect first hand. As the particle accelerated round and round, the atoms and molecules slowed down within it.

There is another  example where time slows down, this time in general relativity, and it involves black holes. A black hole is formed when a very heavy star (usually) collapses in on itself due to the force of its own gravity. Fortunately, our Earth and Sun will never become black holes because their gravity is not sufficient to overcome the nuclear and atomic forces of their interiors. That’s handy, isn’t it?

Wikipedia describes a black hole as  a geometrically defined region of spacetime exhibiting such strong gravitational effects that nothing—including particles and electromagnetic radiation such as light—can escape from inside it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole. The boundary of the region from which no escape is possible is called the event horizon.

In other words a black hole bends spacetime itself, to the point where even light can’t escape. This bending of spacetime means that as you approach a black hole, time will slow down for you relative to the outside world.

If you were approaching a black hole, someone watching from far away would see you approach it, slow down and eventually hover outside it. (There are other complications with ‘watching’ but I won’t bother to explain them here.) If you could somehow resist the terrific force of gravity pulling you into the hole, they would see you through your spaceship window sitting still, having no idea that as you glide past the black hole’s event horizon, thousands of years were passing outside of the black hole. That’s where the theories about time travel start.

Could we find a way of using the super massive black hole at the centre of our own Milky Way galaxy to allow us to bend Time so we could reach vast distances within our lifetimes? Every galaxy has a super massive black hole at its centre. Could they be linked in some way? I don’t know. I am just postulating the theory.

With the billions of suns available it is quite possible there are quite a number of planets circling these suns.That should make the probability of another planet like ours quite feasible, so you would think. However, it is not at all certain that this is so.  Scientists think that our planet is at the optimum distance from our star, the sun, and has the right tilt of axis and other factors which enable life to grow just as it has. Our moon provides both our tides, a calendar and a light for hunting at night (important many centuries ago). Even a small difference in distance from the star, the thickness of our atmosphere, or any of these things would make life improbable.

Consequently, as strange as it may seem, it is quite likely that there are no other planets like ours in the whole of the universe. We are unique. If so, does this rather smack of creation rather than random chance? The whole scale of the universe and infinite distances is something that mortal minds cannot really comprehend let alone the possibility of a multi-universe system and other dimensions. Is heaven somewhere in the realms of dark matter, dark energy or another dimensional universe? For me, science does not weaken my belief that all this is organised… and not just the result of some random act.

When we were talking about the Andromeda Galaxy at my meeting and wondering whether there is any life on any planets in that system, it occurred to me that we are looking at light that came to us from two a half million years ago. Therefore, a lot may have happened on any such planet in that system since then and I just wonder whether some person is using a telescope on that planet looking up at our galaxy and wondering if there is any life here? At this moment, he would see only our galaxy as it was two and a half million years ago, when Neanderthal man was roaming around on Earth but using language just like we do today. Just think of the advances we have made since then that the Andromeda man does not know about. Similarly, I wonder what has happened there in Andromeda in the last two and a half million years? Will it take another two and a half million years to find out, or will something staggering happen before that?

And remember….Time flies like an arrow. Fruit flies like a banana.

K.L. Freeman.

(Chart and image courtesy of EarthSky.org)

‘I WAS SO MUCH OLDER THEN; I’M YOUNGER THAN THAT NOW.’

 

einstein

Someone once said that as they grew older they thought the best part of their life was over. Then they were handed their first grandchild and realised that the best part of their life had just begun.

That might be a slight exaggeration but there is no doubting that grandchildren are indeed a fabulous gift. There is a different relationship than that between your own children. You can spoil them; get told off; give them chocolate; get told off; get involved with their ‘toilet humour’ and get told off. Whether it is the best part of your life is open to debate, as I suppose it depends on what sort of life you have had up to that moment.  (As an aside, isn’t it strange how eating chocolate makes your clothes shrink when you’re not a child?)

There are other advantages of growing older like free prescriptions in the UK, a heating allowance payment, free bus travel and the ability to wander around telling strangers in a trembling voice, “I’m 85 you know”.

Another factor in growing old is that you become invisible. The older you get the more an invisibility cloak seems to surround you. People push past as though you are not there. People no longer look at you in the same way or care what you are wearing. You are no longer an object of desire (although some of us may never have been that in the first place).

The old, or should I say elderly, also start to have certain propensities like “having a fall”. Younger people fall over and you say “he/she fell”. But it seems once you’re over 60 or 65, you “have a fall”. Why is that? If you do fall over, young women come over to you and say, ‘Are you alright, sir?’ It’s the ‘sir’ that denotes you’re past your sell by date.

And for those that are 65 and think that they are still young a quick visit to the medical centre will soon leave you in no doubt that you are not. Signs like  If you are elderly (over 65) you are entitled to a free flu jab hit home the fact that people of that age are considered elderly despite many men clinging to the adage in an old pop song that “you are only as old as the woman you feel”.

And then there are the pills. Pills to get things down, pills to get things up; pills to keep things the same and pills to make things alter. Also, as they get older men tend to gravitate towards women with artificial hips and real breasts where as the young do the opposite.

Anyway, back to the grandchildren. I have digressed. If you have done so too it’s known as the Reader’s Digress. I think things have changed a lot over the last 30 or 40 years. Nowadays it is quite common to see young children being looked after by their grandparents during the day. A quick visit to any park or soft play area will confirm this. This wasn’t the case many years ago and is clearly down to the fact that most mothers now have to go out to work to supplement the family income. I am not going to get into a debate about whether mothers should stay at home with their children until they go to school not. There are so many reasons why mothers may or may not do that and nobody can judge anyone’s individual situation unless they are in that particular family. I think it’s good if mothers can strike a balance between the two by maybe having a part-time job because some of the women I have known can go a bit “stir crazy” if they are left looking after children all day long everyday. That’s where the grandparents become fully functional again by having the children for a day or two.

Oh, and on that point, if any man thinks that staying at home looking after the children is an easy option, then just try it for a couple of days and you’ll soon realise that you would far rather be at your place of work no matter how much you love your kids.

New research has apparently shown that using new technology like smart phones, tablets, computers and video game consoles can reduce mental ageing by 10 years or more. Comparative surveys done in the years 2006 and 2012 show that the average IQ amongst older people was much higher in terms of mental agility by those who had utilised technology a lot more in their lives. This is of great comfort to someone like me  who favours gadgets and playing video games and has now enabled me to justify my comment on my 54th birthday of saying “I’ve turned 45” which is true in one sense if you consider I’ve reversed the numbers. I can also now defend the time spent on such things, as I am clearly showing my concern for my family who will not have to  spend time looking after me from the effects of dementia setting in early. Well, maybe not so much time anyway. Clearly, there is no beginning to my unselfishness. As Bob Dylan sang, “I was so much older then; I’m younger than that now”.

Lastly, the Senility Prayer:

‘God grant me the senility to forget the people I never liked; the good fortune to run into the people I do; and the eyesight to tell the difference.’

K. L. Freeman.

2010-09-26-18-32-532119285181