For as long as I can remember, I’ve been fascinated by the Universe — both the very, very large, and the very, very small — and found great excitement and pleasure not only in seeing the beauty that exists both without and within, as mesmerizing and terrifying as anyone could imagine, but also in the exercise of trying (though not necessarily succeeding) to wrap my head around the immense differences in scale, and the scientific explanations of how things work and how they came to be, explanations that become more detailed and accurate as our tools and our understanding of nature increases. One of the most profound sciences that repeatedly strikes me with awe is astronomy.

This blog post is an expansion on a small piece I wrote on Facebook earlier, with a few extra but relevant — or at least I think so — bits added to the end.

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If I were to name two astronomy photos that are the most humbling to me in the face of the Universe around us, I would firstly name “The Pale Blue Dot”, the image of Earth, appearing as nothing more than the tiniest speck suspended in vast nothingness, taken by Voyager I in 1990 from beyond the orbits of Neptune and Pluto, accompanied by Carl Sagan’s narrative.

Voyager's 'Pale Blue Dot' photo by NASA
Pale Blue Dot: photo by NASA

It’s hard enough to properly grasp the size of our home planet when we’re standing on it. It seems incomprehensibly large to one’s eyes, and even when you know full well that it has finite bounds, it appears as if to be a whole universe unto itself, with uncountable wonders and mysteries, most of them yet to be uncovered. To then perceive it as almost nothing compared to an empty void that despite its vastness is not even close to infinity, can take a tremendous, overpowering toll on the mind and the imagination.

The second would be the Hubble Deep Field image from 1995, where the space telescope looked outwards into a tiny, dark patch of sky which until then had seemed to us like nothing but empty space, yet it turned out to contain galaxies upon galaxies upon galaxies, each containing billions and billions of stars, stretching into unimaginable distance, and backwards into unimaginable time.

Hubble Deep Field photo by NASA
Hubble Deep Field: photo by NASA / Wikipedia

Either one of those two images, the Pale Blue Dot looking inwards, and the Hubble Deep Field looking outwards, and even more so when considered together, tell me that we are are next to nothing in the face of Cosmos, that this place, whatever caused it to exist, was not made for us, and if it was in any way created, it was not created with us in mind. We are too small, too insignificant, to matter in the grand scheme of things. But they also tell me that we are part of something immense, something tremendously big and beautiful. We are in the Universe, and the Universe is in us.

And when we are so small in the face of it all, when our existence is so minuscule as to seem overwhelmingly meaningless, then we should value it even more than we seem to do. We may not matter much to the Universe at large, it may not even know or notice that we are here, but we should certainly matter to each other, and we should make the most of our tiny place on this mind-boggling stage, and cherish the experience of being alive, together.

Welcome to the Universe. It is the biggest thing you will ever know.

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Hubble and the Unexpectedly Crowded Sky

The history behind the Hubble Space Telescope, an embarassing failure that was turned into a tremendous success, and the birth of the idea and the mission that became the Hubble Deep Field image.

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Where is the Hubble Deep Field at?

And to think that such a daunting and mind-boggling image as this is taken from somewhere as homely and familiar as just above the Big Dipper, which even most children will easily be able to find in the sky. That’s practically in the back yard.

Screen capture from Stellarium

The little yellow square shows the approximate location of the Hubble Deep Field. Not to scale, mind you. The actual area is far smaller, about a couple of pixels’ worth in this image, or as the above video says, the head of a pin held at arm’s length.

From Wikipedia: The field that was eventually selected is located at a right ascension of 12h 36m 49.4s and a declination of +62° 12′ 58″; it is approximately 2.6 arcminutes in width, or 1/12 the width of the Moon.

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Taking a Closer Look

All those galaxies far, far away, what would they look like really, really close up? Well, being so far away means not even Hubble nor any other of our existing telescopes will be able to give you a nose-to-nose encounter. Rest assured, though, that each and every one of them is, in the words of Dave Bowman, full of stars. The one galaxy that we can have a closer look at, however, is our nearest neighbour Andromeda, a mere 2½ million light years away.

“The new Hubble image of the [Andromeda] galaxy is the biggest Hubble image ever released and shows over 100 million stars and thousands of star clusters embedded in a section of the galaxy’s pancake-shaped disc stretching across over 40 000 light-years.”

The jaw-drop moment is, or at least it was to me, when you reach the amount of zoom where you see mostly image noise … and then you realize when it keeps on zooming that the “noise” is actually individual stars. Lots and lots and lots of stars, floating like the tiniest droplets in mist, except these droplets are a million miles or more across, and light-years apart. You may also note a considerable difference in star density when comparing the centre of the galaxy to its outer rim territories.

I’ve added a few screenshots to demonstrate, but why take my word for it, when you can zoom it yourself right here?

Hubble Andromeda Zoom full view

Full view, showing about a quarter of the Andromeda Galaxy, like a smooth, translucent veil against the blackness of space, just like we know it already.

Hubble Andromeda Zoom max zoom

Almost halfway there, with what looks like background digital image noise. The larger stars you see here are all members of our own Milky Way galaxy.

Hubble Andromeda Zoom max zoom

Zoomed in all the way, and the “image noise” resolves into a glittery jumble of individual stars. And if there’s anything we’ve learned about stars in recent years, it is that they tend to have planets around them. This has been shown to be true of stars in our own galaxy, and there is no reason to think that the Andromeda galaxy should be any different in that regard. Here be worlds, upon worlds, upon worlds.

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From Big Bang To Black Hole: The Mind Trip

Inspired by the article “Goodbye Big Bang, Hello Black Hole? A New Theory Of The Universe’s Creation” at, by Elizabeth Howell, on September 18, 2013.

I just read an article at Universe Today which, though it was published over a year ago, had so far evaded my attention. It speaks of the possibility that our universe did not come about by way of a Big Bang, but rather that it is something like the inside of a black hole resulting from the collapse of a dying star in a four-dimensional universe (presumably one dimension is lost in the process), and perhaps what we conceive as a Big Bang is the inside-out version that collapse, at least as far as I can understand.

Illustration borrowed from the above mentioned article. With apologies to those involved.

It’s a dashingly interesting and mindboggling concept, but it would seem that it merely pushes the problem of the great coming-into-being of everything (I generally avoid the word “creation” as it implies that someone is doing the creating, which is a whole ‘nother bag of wossname) one more generation backwards. What came before the hypothetical four-dimensional star which hypothetically collapsed into our tree-dimensional universe? Was its universe, too, born out of a collapsing five-dimensional star in a previous universe? And before that?

Illustration borrowed from the above mentioned article. With apologies to those involved.

It smacks slightly of “turtles all the way down”, but I am not one to say that that’d be an incorrect conclusion. Turtles, after all, are known for impressive longevity, if left to to their own devices under favourable circumstances, and as far as turtles go, universes are long-lived indeed.

Lonesome George 1.jpg
Example of particularly long-lived turtle (Wikipedia)

But wait. Aren’t black holes supposed to steadily consume all available matter around them? Would not that cause a steady stream of further matter to be injected into the universe born of that black hole? Our universe? Would that not make the sum total matter in that universe anything but unchanging? Doesn’t that run against the rule that the sum of mass and energy is constant? Or is the content of the resulting universe limited to the matter present at the moment of collapse? If the latter, where does the later consumed matter go? And how the heck do we define matter on that scale anyway? A previous universe with a higher number of dimensions (I’ve barely been able to wrap my mind around four dimensions, I dare not think what five would be like, not to mention six) would be unlike anything we know from our three-dimensional one. And black holes in our universe, do they lead to two-dimensional universes? What happens when you run out of dimensions? Will the next generation be one of Flatlanders, or are the dimensions themselves simply rearranged and redefined so that there is no real beginning or end to a long, continuous line of stars dying and universes being born?

Carl Sagan on Flatland and Flatlanders (Youtube)

I wish that I could say that questions like these do not keep me awake at night, and indeed I can, but during my waking hours they tend to buzz around my cerebrum like infuriatingly annoying house flies, and there tends to be rather a lot of them. Though before you start questioning my personal hygiene, I am quite sure that those aren’t actual house flies, as their buzzing takes place inside my head, and at least so far no-one else has actually reported seeing them.

My point, if there is one, is that every new discovery, every new theory, even if it should happen to provide answers and explanations to existing questions, tends to present anywhere from a single one to a whopping multitude of new ones. But that’s the astonishing beauty of science: We will never run out of things to find out, questions to ask, amazing stuff big and small to drop our jaws at, as well as little things, at a more manageable magnitude, to keep us occupied in our everyday lives. It’s bloody marvellous!

Welcome to the Universe. It’s the biggest thing you will ever know.

Related links:

Words from Planet Sagan

I recently came across the 100th comic strip by Zen Pencils, from almost six months ago, which celebrates some of the most famous and profound words by Carl Sagan. Anyone who has read or heard anything by Sagan will no doubt recognize this:

This is of course only the top of the strip. Click the image to go the whole mile. And I mean mile. It’s a looong strip.

If you hear Sagan’s voice while you read the comic strip, you’re doing good. If not, you may want to watch the following Youtube video, which is taken from the science update appendixes to the “COSMOS” DVD series:

And in case you don’t mind hearing and reading it one more time (personally I don’t think that I can ever hear it too many times, I still get goosebumps every time), here is an animated version, putting the words themselves into motion:

Despite it being by now well over 30 years old, I believe “COSMOS” series would be a good watch for anyone. A good portion of the science may be a bit dated (the DVD and VHS series have science updates added to many of the episodes), but the most important thing is how it conveys a spirit of curiosity, the principles of science, the sense of adventure and awe in the face of the Universe, both the very big and the very small, the message of scepticism and critical thinking, of logic and common sense, and of respect for everything and everyone around us.

If you are unfamiliar with but curious about the COSMOS series, or have seen it before and wish to revisit, it is available on YouTube. There’s a playlist of all thirteen episodes, each about an hour long. Click here to watch.

To me, “The Pale Blue Dot” provides perhaps the ultimate perspective to who and where we are in the Universe, and how small, insignificant and fragile we are compared to the whole, that we have no special or privileged place in all of Cosmos, and yet how close and how important we are to each other.

We are here! We are ALL here!

And then, of course, there’s music. By his own statement, Carl Sagan wasn’t very good at singing, but it’s amazing what a little technological help can do.

Related links:

“My God, it’s full of galaxies!”

Our own galaxy, the Milky Way, contains somewhere between 200 billion and 400 billion stars. The Universe, according to Wikipedia, contains more than 170 billion galaxies. According to findings of recent years, most if not all stars have at least one planet orbiting around them. If the average galaxy, to make a semi-educated guess, holds about 300 billion stars, then we’re talking about some 50,000 billion billion stars. That amounts to quite a mind-boggling lot of planets, if you’ll pardon my vast understatement.

If just one in ten stars have a planet in their habitable zone, and one in ten of those planets are earth type (made of rock, possessing an atmosphere, and more or less the same size), that’s still 500 billion billion planets with potential for harbouring life as we know it. Not to mention that we’ve no idea, really, how life considerably different from anything we know might arise and evolve under considerably different conditions on considerably different planets.

I’m pretty sure we’re not alone, though our nearest neighbours may be somewhat farther than just a quick stroll down a country road.

Continues below the video.

This computer-generated video contains only 400 000 galaxies, and still looks amazing.
Open video in new window.

For scale and perspective, consider the Hubble Ultra Deep Field image. At just over 3 arc minutes across (1/20th of the width of your pinky nail at arm’s length, or 1/10th of the width of the moon in the sky), showing a whopping 10,000 galaxies. And this is only what the Hubble telescope could see at the given exposure (11.4 days – you try to hold a camera steady for that long). The longer the exposure and sharper the telescope, the farther out one can look.

And that’s just ten square degrees. The full sphere of the sky is 41,253 square degrees. If evenly distributed, this amounts to 41,253,000 galaxies, which in itself is a pretty large number to wrap one’s mind around, though it is easily dwarfed by the 170 billion ones already mentioned. Future telescopes will be sharper and more light-sensitive yet, likely to reveal even more galaxies and in greater detail.

Though if you look at the night sky, even if you’re in a place with little or no light pollution from nearby cities or residential areas, with the possible exception of the Andromeda Galaxy which you will only catch sight of if conditions are right and you know where to look, every point or patch of light that you see are only relatively nearby stars and nebulae, and no more than a handful thousand of those at best. In other words, you see only a fraction of a fraction of a fraction of what’s in our own galaxy, let alone any other.

The most awesomely amazing things are out there, far out, in the dark patches between the stars that you can see, invisible to our eyes, and visible to our technological viewing aids only through special effort. But they are out there. And I’m pretty sure that right now, on at least one of the planets around one of the stars in one of those countless galaxies, someone is looking up at their night sky in our direction, wondering if there’s anyone out there.


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