As darkness falls and the shades are drawn I sit here in the fading light on the 100th anniversary of Irish author Bram Stoker's death.
A clap of thunder. Hail bursts from lowering thunder clouds.
A shadow flits across the window... is it someone hurrying home to escape the foul weather? Maybe Stoker's creation still stalks the landscape?
Just as the Dracula of Stoker's novel required sustenance by feeding on the lifeblood of others, so too we have discovered a universe where strange creatures are nourished by matter that courses through the cosmos.
Black holes rip apart anything that strays too close to their clutches, galaxies like the Milky Way cannibalise smaller siblings, and the universe blazes with violence at high-energy wavelengths.
On a smaller scale, a white dwarf star scavenges its orbiting companion, comets are flung from the heavens to fall like Thor's hammer on an unsuspecting world, and gravitational forces cruelly warp and melt the interiors of moons.
When the sky clears and the world is silent though, we can contemplate the stillness of the night, knowing that life clings tenaciously to this blue marble despite the perils: Suddenly those celestial demons are tamed as we turn our gaze skyward and marvel.
What's the furthest thing you can see with your naked eye? The Moon? The Sun? Saturn? Maybe it's a star; they're much farther away after all. And they're all at different distances.
Not even close.
With the naked eye, in a dark sky, away from neighbourhood security lights and the neon-glow of urban skies, in the closing months of the year, overhead lies a dim patch which can just be seen...
The Andromeda Galaxy
Messier 31 (M31) as it's known, is a sister galaxy of the Milky Way, one of many but certainly its closest. This is a spiral galaxy much like our own but twice the size. Our eyes can only see the glow of the galaxy's central bulge and, when photographed it spans an area six times the width of the Moon.
Currently the Andromeda galaxy is about 2.2 million light years distant and due to the mind-warping laws of the Universe, that means the light that enters your eyes when you look at it is 2.2 million years old. You see it as it was before Man walked the Earth.
One of the consequences of light having a finite speed limit (186,000 miles per second) is that you can never see anything as it ever is, only as it was. And the further away an object, the older the light we see. So in some sense, the Universe acts as a time machine! We can only ever look into the past. We can't even actually look at the present.
There's another unsettling fact about M31 - it's careening towards our Milky Way at between 62 and 87 miles per second (about 400 light years every million years) and both galaxies are expected to collide in about 4.5 billion years.
Since there's an element of uncertainty in velocities and trajectories, it's not known for certain what will happen, but the expectation is that the two galaxies will eventually merge and form a large elliptical galaxy. Both will lose their aesthetic and beautiful spiral structures as a result.
How our solar system will fare is also unknown, should the galaxies merge. If the galaxies don't merge, then there's a small possibility the solar system could be ejected from the Milky way, out into the dark void between the galaxies. On the other hand, there's also a chance the solar system could do a cosmic swap and end up in the Andromeda galaxy rather than the Milky Way.
Whether anyone will be around when that happens is very much open to question.
So when you look up at that faint fuzzy patch on a dark and moonless night, imagine you could see the ghostly light of a galaxy, six times larger than anything else in the night sky, as it hurtles towards a cosmic kiss with the Milky Way that will change the lives of both galaxies forever.
A clap of thunder. Hail bursts from lowering thunder clouds.
A shadow flits across the window... is it someone hurrying home to escape the foul weather? Maybe Stoker's creation still stalks the landscape?
Just as the Dracula of Stoker's novel required sustenance by feeding on the lifeblood of others, so too we have discovered a universe where strange creatures are nourished by matter that courses through the cosmos.
Black holes rip apart anything that strays too close to their clutches, galaxies like the Milky Way cannibalise smaller siblings, and the universe blazes with violence at high-energy wavelengths.
On a smaller scale, a white dwarf star scavenges its orbiting companion, comets are flung from the heavens to fall like Thor's hammer on an unsuspecting world, and gravitational forces cruelly warp and melt the interiors of moons.
When the sky clears and the world is silent though, we can contemplate the stillness of the night, knowing that life clings tenaciously to this blue marble despite the perils: Suddenly those celestial demons are tamed as we turn our gaze skyward and marvel.
What's the furthest thing you can see with your naked eye? The Moon? The Sun? Saturn? Maybe it's a star; they're much farther away after all. And they're all at different distances.
Not even close.
With the naked eye, in a dark sky, away from neighbourhood security lights and the neon-glow of urban skies, in the closing months of the year, overhead lies a dim patch which can just be seen...
The Andromeda Galaxy
Messier 31 (M31) as it's known, is a sister galaxy of the Milky Way, one of many but certainly its closest. This is a spiral galaxy much like our own but twice the size. Our eyes can only see the glow of the galaxy's central bulge and, when photographed it spans an area six times the width of the Moon.
Currently the Andromeda galaxy is about 2.2 million light years distant and due to the mind-warping laws of the Universe, that means the light that enters your eyes when you look at it is 2.2 million years old. You see it as it was before Man walked the Earth.
One of the consequences of light having a finite speed limit (186,000 miles per second) is that you can never see anything as it ever is, only as it was. And the further away an object, the older the light we see. So in some sense, the Universe acts as a time machine! We can only ever look into the past. We can't even actually look at the present.
There's another unsettling fact about M31 - it's careening towards our Milky Way at between 62 and 87 miles per second (about 400 light years every million years) and both galaxies are expected to collide in about 4.5 billion years.
Since there's an element of uncertainty in velocities and trajectories, it's not known for certain what will happen, but the expectation is that the two galaxies will eventually merge and form a large elliptical galaxy. Both will lose their aesthetic and beautiful spiral structures as a result.
How our solar system will fare is also unknown, should the galaxies merge. If the galaxies don't merge, then there's a small possibility the solar system could be ejected from the Milky way, out into the dark void between the galaxies. On the other hand, there's also a chance the solar system could do a cosmic swap and end up in the Andromeda galaxy rather than the Milky Way.
Whether anyone will be around when that happens is very much open to question.
So when you look up at that faint fuzzy patch on a dark and moonless night, imagine you could see the ghostly light of a galaxy, six times larger than anything else in the night sky, as it hurtles towards a cosmic kiss with the Milky Way that will change the lives of both galaxies forever.
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