Hubble is a lie

Surely many of us have marveled at the stunning photographs that the Hubble space telescope has given us. I mean wow, what an amazingly, incomprehensibly huge and marvelous universe we live in! Who can forget amazing shots like the famous Horse Head Nebula:

Or the astounding Pillars of Creation:

Or, my personal favorite for sheer You are insignificant humility, one of the many Deep Field photographs showing thousands of galaxies in what, to us, would be a barely perceptible speck in the sky:

I mean wow. Space isn't just incomprehensibly large — traveling between any two stars in the above nebulae would likely take, with our current technology, tens of thousands of years — it's also beautiful. It's like God is some sort of cosmic artist!

But it's a lie. Space doesn't look like that, at least not to human eyes. I mean the question of what space "looks like" is kind of odd when you think about it — alien creatures who perceived x-ray light would see a very different-looking universe than we do. The concept of "looks like" is something deeply constrained by our human embodiment. But what would space look like to us if we were out there? Could we see those stunning swirling nebulae if we could get close enough to them (bearing in mind that "close", as in the the above pictures, is still tens of thousands of light-years away)?

No. No we could not.

Deep space photography is, for the most part, boring black and white. But then, to represent various elements, filters are applied. So they apply a brown filter and it represents sulfur, or a blue one and it represents oxygen. The composite image you get is the totally amazing menagerie of colors. But the colors are imposed on the pictures, not 'out there' in nature. From Hubble's site:

“There are no “natural color” cameras aboard the Hubble and never have been. The optical cameras on board have all been digital CCD cameras, which take images as grayscale pixels. 

Sometimes the color is as natural as possible. However, the color given to the images is not just “artistic embellishment.” The images are, indeed, downloaded as black and white, and color is added for a number of different reasons – for example, to show the dispersion detail of chemical elements and highlight features so subdued that the human eye cannot see them.”

It gets lamer: if we could travel toward one of those nebulae, we would see a whole lotta nothin'. This is because of an optical principle called conservation of surface brightness. As you got closer to a nebula, its brightness would disperse over a larger area of your vision so that it never appeared to get any brighter. It'd be pretty, sure, but instead of looking like the stunning Horse Head or Pillars of Creation photos, it'd look more like this:

We like to think of space as beautiful and exciting. Science fiction movies and games feature space ships whooshing through bright clouds of swirling gasses, dense asteroid fields, and stunning planets flanked by eye-popping stars. The truth is, space is — to our eyes, anyway — pretty bland-looking. It's mostly empty, it takes a really long time to get anywhere, and it wants to kill you in many horrible ways.

But hey — on the upside, we can at least be glad that we have the technology to 'see' what our eyes cannot. Even though stuff is really far apart and far away, there's still an infinity of neat stuff to discover. Space — empty and vast though it may be — is still really, really damn cool.