Source: Hubblesite.org

Yet, being the source of pretty pictures is the superficial way to look at Hubble, like judging someone by their shoes. We have obtained a tremendous amount of information from these optical observations as well, such as refining the measurements that led to the concept of “dark energy.” In a nutshell: after the initial acceleration of all the mass in the universe from a very small point, gravity should have been slowing things down, dragging its metaphorical feet against the coasting bike of space-time (no, I’ll never be asked to write popular science articles.) Instead, the expansion of the universe is accelerating, and something must be feeding energy into this. I could have continued the space-time bike simile by comparing it to going downhill, but that acceleration is caused be gravity and I’m now confusing the hell out of even myself. Let’s let someone else do this (autoplay video at that link – I wish people would stop doing crap like that.)

Hubble has also contributed a lot to our knowledge of planetary formation, as well. The photos that I highlight in this post disproved a prediction by astronomers that planetary discs would typically remain hidden from our view by surrounding dust clouds. Hubble has even imaged a planet itself around another star, something that is remarkably hard to accomplish:


There’s a little bit of trivia that is worth knowing, if you’ll permit me to return to the idea of Hubble as a camera (just try and stop me!) The bare truth is, every camera, every method that we have of producing images from light, fudges things a bit. Film emulsions contain metals that change their nature when exposed to light, forming crystals, and digital sensors generate a difference in electrical charge. But neither of these can determine the difference between wavelengths except in a very broad range, mostly what we call visible light – in other words, they cannot differentiate color. To accomplish this, they must filter light through substances that permit only specific wavelengths; in film, that’s the emulsion base, a colored gel in which the metals are suspended, and in digital, it’s a membrane over top of the digital sensor. It’s no different for the Hubble Space Telescope, which has colored filters that can be interchanged over its own digital sensors. Every color image from Hubble is a composite of several strictly monochrome images sent back to earth, edited to reintroduce the color, and in most cases enhanced to increase the contrasts between them. A typical computer display does not even remotely approach the range of light and color that our eyes can see, so to provide a better idea of the subtle differences within any photographic target of the HST, the images must be altered. It’s no different than any image I produce myself and put here on the site. This article from Sky & Telescope magazine, used with permission by Hubblesite.org, explains it in more detail.

And finally, I refer you back to this post from two years ago, which contains the video made from the Ultra Deep Field photos, simply because it’s one of the coolest animations ever made. Yeah, you might have seen it already – so? Watch it again. It’s a great dose of perspective, in both directions. While it is easy to feel insignificant in comparison to the unfathomable distances involved, there’s the other side of the coin: we figured out how to actually see this. Damn clever little apes, aren’t we?

But then, I guess we would think that…

Here’s how it works. A normal lens, as almost anyone can tell you, “bends light,” but what this actually means is not as well understood, and often poorly illustrated. Let’s say you have a star, which only looks like a point of light from our distance (I added the twinkle for artistic statement.) It’s emitting light in all directions, so we can take a few paces to the left and still see it, or across the continent, or (should we be able to travel that far) all the way on the other side of it. The light from it is actually a spreading globe of photons, and we see just the one stream that meets our eyes (yes, that’s an eye in the upper part of the illustration.) A lens, however, catches all of the streams that meet its surface, essentially a cone, and bends the light to make all of these streams converge back down into the ‘dot’ of the star – provided that you’re the right distance for that particular lens, called the focal length.

Gravity can be strong enough to bend light. This is not entirely true, since what it does is curve spacetime, which is what the light travels through – you can draw a straight line on a piece of paper and then curl the paper, curving the line. Close enough. With very large galaxies, or more often a whole cluster of tightly-packed galaxies, the gravity can be dense enough that the light from a distant star or another galaxy, out of our sight behind the first, is bent away from its original path that would normally have not even come near us, going instead to Proxima Centauri or someplace. If the alignment is just right, we can see multiple distant objects in several mirror positions around the lensing galaxy, as the light path is bent according to the strength of the gravity at certain points around the lensing galaxy. Placed exactly right, and with fairly high uniformity in gravity around the galaxy, and the distant hidden subject gets distorted into a surrounding ring, which is what we see here with yellow galaxy LRG 3-757. It obscures our direct line of sight to the distant blue galaxy, but we get a nearly spherical path from around the edges, as it were.

What’s interesting about gravitational lensing is, if we were along the line of one of those original paths from the distant star or galaxy, continuing an imaginary path unbent past the gravitational lens (see point A in the illustration,) we would have a perfectly clear line of sight to the distant subject and never see it, since the light was redirected. And in fact, we can only speculate how often this actually happens, since we have no way of knowing. Gravity distorts the path of all light, but usually in such small increments that it doesn’t matter much.

When Einstein proposed General Relativity, which indicated that gravity wasn’t an attractive property but rather an effect of spacetime itself, we didn’t have the ability to test it out in any way, but plenty of astrophysicists hashed out the details looking for errors or implications. One Fritz Zwicky extrapolated it to mean that areas of very high gravity, such as close-packed galaxy clusters, could bend the light paths from more distant objects. It’s simply fascinating to see theories of such a bizarre nature be proven with remarkable images such as this. Another curious implication of General Relativity is the collapsed neutron star usually called a black hole, which would also lens light that passed a certain distance away, but completely capture light that passed too close. We should be able to see lensing from such as well, except that, to our knowledge, black holes have only occurred in the centers of galaxies, and might even be necessary for galaxy formation. Thus it is entirely possible that the lensing galaxy you see in this image is home to a black hole deep in the center, but we do not see a ‘hole’ because it is surrounded by stars well outside of its event horizon, the imaginary sphere around it where light cannot escape. There is even a very very faint chance that some of the light in that central smudge is from stars on the opposite side of a central black hole, bent towards us by the gravity.

As lenses go, by the way, LRG 3-757 is a whopper. About 4.6 billion light years away at the time the light left, it’s one hell of a focal length. It’s also a tad heavy to carry around, as you might imagine, so not really useful to look at anything else. And as seen, its field curvature is kind of egregious.

Here’s another cool thing. The universe is expanding, and the light reaching us now is from objects that have long since left those positions. The distances between LRG 3-757 and the warped galaxy forming the ring are changing, and this curious optical affect will vanish after a while – probably well outside of our lifetimes. At the same time, others that we cannot see now may appear later on as the cosmic focal length changes.

Be sure to check the original APOD page and click on the image to see the high resolution version, which shows much more surrounding detail and is a nice starfield image on its own. And reduces the resemblance to HAL 9000. Once again, we have these images thanks to the Hubble Space Telescope, which is Photographer of the Decade (twice in a row) as far as I’m concerned. I’m gonna be frustrated when it’s decommissioned…

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My thanks to Chris L. Peterson at Cloudbait Observatory for supplying a pertinent detail regarding LRG 3-757 on the Starship Asterisk forums, a great place to ask questions.

While I managed to spot a few meteors, I don’t think I captured any on film. And yes, I mean literally on film (though not literally captured – oh, never mind) since I was using both the digital SLR and the Mamiya 645 medium format camera. I’ve had much better luck with film for astrophotography, since it produces more color and is less prone to noise for long exposures, but we’ll have to wait a bit to see what I might have gotten – the few meteors I spotted probably fell outside the view of the 45mm lens (which is a nice, wide angle on 6×4.5 film, roughly equivalent to a focal length of 24mm on film cameras – why are we still calling them “35mm”? – and about 15mm on DSLRs.)

The five frames I got on digital showed no telltale streaks except from aircraft, which were still far too busy when I was out after 11 PM – this is kind of a north/south airway region. “Five frames?” you say (go ahead, don’t leave me hanging.) But yes, the point of meteor photography is that you’re never going to capture anything if you wait until you see it to trip the shutter, because they’re visible typically less than a second, so you lock open the shutter and just wait for something to cross your field of view. I was doing exposures between five and fifteen minutes with the digital, and the ambient air temperature was 2°C (36°F,) so both sets of batteries died out after an hour. Had I seen more than three meteors, I might have continued a little longer with the Mamiya, but I figured I was cold enough for the sparse activity last night. There was frost on the tripod legs as I packed it in.


That is pretty much my luck with meteor showers. Most happen to fall on evenings with poor visibility, regardless of how long we might have gone with crystal skies leading up to the showers. When we do get clear skies, the activity is pathetic. With one exception.

In 2001 I had just moved to Georgia, and on the evening of the Leonids, I spotted a spectacular airburst, resembling a crashing plane, on the drive home – on the interstate, by a brightly lit exit, from inside the car. It would have been awesome in a dark-sky location. So I poked around until I found a nice dark location and spent most of the early morning out there. It was a fabulous night, and I was maintaining a count of all the meteors I was seeing directly – glimpses and corner-of-the-eye didn’t count. In the first hour I was over two dozen, having shattered my old personal record of thirteen for one night when living in central New York, where the skies were quite dark and I often walked at night. By 4 AM when I was about to wrap it up, I spotted twenty just in the time it took me to pack up the camera and tripod, convincing me that the peak was coming and I should probably hang around a bit longer. That morning, I stopped counting at three hundred clearly seen, with an unknown number glimpsed, all in about five hours.

One in particular was spectacular, burning parallel to the horizon and lighting up the entire sky, fragmenting and leaving multiple trails (I checked the next day to be sure the ISS hadn’t re-entered by accident.) Even more interesting was when I realized that the tree in my field of view was flickering, indicating some light coming from behind me and suggesting I was missing a similar light show back there.

Now, the sad confession: I have no photos of this whatsoever. Well, I have most of a roll of film that I shot that night, but I wasn’t stocked up and what I had handy was Kodak Portra 400 left over from a wedding. ISO 400 is a nice speed for night photography, fairly light-sensitive and color-responsive yet not too grainy to make things ugly, but Portra 400 is an exception because of a little something called reciprocity failure. Welcome to advanced film properties.

Reciprocity is the photography function that ties together aperture, shutter speed, and ISO, and basically means you can change any of these settings by a given amount, and change either of the other two in the opposite direction by the same amount (called the reciprocal,) and get the same exposure. So you can get very fast shutter speeds if you can open your aperture far enough – the reduction of light from the shutter is compensated by the additional light through the lens. In the realm of low light photography like at night, you can compensate by leaving the shutter open for long periods of time, and can make a moonlit scene appear to be daylight if you wait long enough.

Reciprocity failure is where this breaks down. Due to the nature of the chemical reaction to light, low amounts of light don’t always register on film, and so lengthening the exposure has a reduced effect, with diminishing returns depending on the amount of light and length of exposure, often with a color shift because the different layers of emulsion have different sensitivities. Some films, like Fuji Provia 100, handle this fairly well, but Kodak Portra 400 is not among them. The images I have from that evening are all blue, grainy, and show almost no stars at all, much less meteor streaks. For the best opportunity I’ve ever had, I totally blew the pics. Even the spectacular airburst, which might have overcome the film’s flaws, was well away from the direction the camera was aimed at the time.

And sometimes that’s how it goes (or at least it does for me.) The cool stuff happens when you’re not in a position to exploit it, and when you’re prepared, it’s quiet. Last night was hardly a shower, or even a trickle. One of these days I’ll capture a decent meteor storm, but in the meantime, I’ll experiment with lens tricks like this one. Bonus points if you can tell me how it was done ;-)

Later on, I’ll provide a quick tutorial on eradicating noise caused by bad sensor pixels from your digital images. Some Photoshop tricks are actually quite useful.

It was found when the Hubble Space Telescope was doing survey images of Pluto to map out the area as best we can, since we have a planetary probe on its way there, the New Horizons probe (definitely a cool site there.) Pluto is so remote that we have only smidgens of information about it, and New Horizons is going to expand that by thousands of times. Launched in 2006, it will not be making its rendezvous until 2015.

Now, a quick illustration. P4 is estimated to be between 13 to 34 kilometers (8 to 21 miles) across, the size of a moderate city, or Atlanta’s airport. Being able to spot it from Hubble’s orbit around Earth is much the same as sitting here in central North Carolina and being able to see a penny – in Chicago. The best resolution images we have of Pluto itself, which is about 2,390 km, are only a few dozen pixels across themselves. We’re actually kind of vague on P4′s size not just from the smudge it makes on the image sensors, but because we don’t know how reflective it really is. If it’s highly reflective, it’s among the smaller measurements, but if it’s low in reflectance it can be at the larger end. It is supposed to be much the same reflectance as Pluto and the other moons, since they’re all assumed to be from a collision many millions of years back, and thus composed of the same elements. But this isn’t known by any stretch, and P4 could be an extraneous body from the Kuiper Belt captured into Pluto’s gravitational field. That’s part of the fun of working at this kind of distance from a subject.

There are tricks, however. We had a few guesses at how much light Pluto itself reflects, which would make its diameter different depending on each, but then pinned down its size pretty accurately by watching Charon eclipse it, as well as watching it eclipse a distant star. Corroborating methods like this help a lot, but New Horizons is going to make all of that look like scraps of paper.

The probe is taking so long to get there since it is limited on the fuel it can carry, as well as what its mission is. New Horizons used an orbital pass around Jupiter to serve as a free slingshot, accelerating it without fuel, and will be coasting most of the way to Pluto now. The mechanics of launching probes and such is responsible; Earth’s gravity has to be defeated for every milligram we send into space, and this includes fuel as well. The more fuel, the more fuel is needed just to move the fuel, and a process of diminishing returns comes into play. It doesn’t take much before you’re looking at a bigger launch vehicle, of which our options are limited, and it can actually reach a point (with something much larger than a probe, anyway) where the fuel is not efficient enough to boost a certain quantity out of earth’s orbit. In other words, one can’t just keep building bigger rockets, at least until we discover a fuel source that provides more bang for the gram.

Once in space and at a sufficient speed to reach a target before the batteries run down or mankind turns into another species, such probes can coast – there is too little in space to provide drag and slow them down, of course. But this works a little against the goals, too, and it shaped the profile of New Horizon’s mission. Fuel would also be needed to slow the spacecraft and put it into orbit, like Cassini is in around Saturn, and this wasn’t available, either, so New Horizons is instead doing a flyby, passing Pluto only once before continuing onward to study other Kuiper Belt Objects. This is part of the reason that Hubble is scouting the territory: the more we know ahead of time, the better we can plan activities for its brief time up close.

There’s another reason, too. Light, and by extension radio waves, takes over four hours to reach Pluto from Earth, and the same amount back, so “real time” instructions to the probe just ain’t happening. The instructions need to be planned in advance and sent to the probe, and there’s a distinct limit on how many changes can be made based on new information from the probe itself. For safety’s sake, there also needs to be enough time to get confirmation signals from the probe, so we’re sure it received everything without dropping out portions (and there’s no cell towers around.)

There’s yet more planning involved. In order to use that orbital assist trick around Jupiter, the locations of Jupiter, Pluto, and Earth in their orbital paths had to coincide so that the probe could be aimed correctly and not have to waste fuel and time zig-zagging across the solar system. While we tend to think of the planets lining up like they’re diagrammed in astronomy textbooks, in truth they’re all tracing their own orbits and can be widely varying in both distance and direction. Our window of opportunity to use these mission parameters was pretty narrow, and we would not have had the opportunity to do this again for three hundred years. When I first heard that Congress had voted down funding the mission, I was livid at the stupidity – you don’t put off exploratory missions for three centuries. Apparently, wiser heads prevailed, because funding was restored and New Horizons was able to be launched before the window closed.

I mentioned “Kuiper Belt” a few times and you may be wondering what that is. Basically, it’s the sawdust left over when you make a planetary system. Clouds of interstellar dust form into disks, and ever so slowly, mutual gravity causes a star to form at the center while planets form further out. The larger planets attract nearby bits of matter and incorporate them, sweeping clean the space in their orbital area, but at the outer edges of the system disk, things are too spread out to attract each other well, so they tend to stay scattered and small. The Kuiper Belt is very much like what the original disk that eventually formed the planets was like, except with fewer gases (more easily attracted to the larger bodies) and with more ice, because of its distance from the sun. The Belt serves as the source of most of the comets we see here from Earth, “dirty snowballs” of ice and grit that had been orbiting happily way out there until some other body passing nearby dragged it by mutual gravitational pull, like two magnetic balls passing close to one another. With the angle of momentum altered, the comet now progresses on an elongated elliptical orbit deeper into the solar system, generally getting realigned as it gets closer to one of the larger bodies, which isn’t always the sun – some comets actually whip around Jupiter instead (or crash into it.) Of course, far more get re-aimed in virtually any other direction and trundle off into deep space…

In four years, we’re going to be getting fantastic images of the distant edge of our planetary system, which is going to add a lot to our knowledge about how the solar system formed, no doubt confirming a few theories as well as trashing a few. That is, if the probe can find it. When New Horizons was launched, Pluto was still a full planet, but in the intervening time it has been demoted to dwarf planet, which might defeat the probe’s programming. I wonder if Neil deGrasse Tyson thought this through carefully…?

First off, the fact that this has a scientific-sounding moniker is what causes some of the problems, but it isn’t exactly a scientific principle (at best, it is philosophical,) and in fact, there are several variations of it. It’s also rather contentious even among its supporters, so holding it up as evidence that science supports a divine creator shows a poor understanding of the overall issue, much less the various discussions of individual aspects.

The aspect that is sometimes referred to as the weak anthropic principle essentially states that what we see in the universe is what we can see; the parts that seem encouraging of life forming are what we notice simply because those conform to the senses that we developed. In other words, we’re aware of gravity because we need it, and the catalytic effects of liquid water and oxygen because life as we know it could not have formed where it doesn’t exist. This is, in effect, the opposite of how the anthropic principle is often used by religious apologists, because it makes it clear that the only things we’re likely to see is what favors us – a universe with the conditions for life is where we will reside and thrive, as opposed to someplace that was directly hostile. Kind of a “duh!” argument, and completely ignoring that our existence in a hostile environment would be far better evidence for divine intent.

Douglas Adams presented the idea of a (curiously self-aware) puddle of water looking at the basin it filled and thinking that the basin fit the shape of the puddle so well, it couldn’t have been an accident. This is exactly the situation we find ourselves in with invoking the anthropic principle, where vanity makes this very contemplation something that must revolve around us as a species rather than exactly what we should expect to find. Life will only exist where the conditions are right, just as fire will only exist where there is adequate fuel, oxygen, and a high enough temperature to start the process.

Life on this planet does indeed require a confluence of conditions, from a narrow range of temperatures to the ability for chemicals to catalyze and exchange energy, and several factors are key – remove any one, and no life can form. This seems, at first, to be very intriguing, but it requires careful examination as well. It is very hard to look even at the tiny fraction of the universe that makes up our solar system and think that we’re someplace special. Out of eight planets, 166 (known) moons, and countless asteroids and comets, we know of only one place where life has occurred – that’s not exactly encouraging for an “ideal” set of circumstances. Even on this planet alone, there is only a narrow shell just a few miles thick where life can be supported, from lower atmosphere to a fraction underground and under the surface of the sea, and the places where humans can survive are even fewer. We are, in essence, trapped within a tiny thin sphere, and venturing outside of it exposes us to conditions so hostile that we would die extremely quickly, due to everything from lack of air to large doses of unshielded radiation. Few people know that, had a solar flare occurred during any of the moonwalks, the astronauts would have died on the surface, none too pleasantly. We also can’t go very far underground, and that’s where most of the planet is. Earth is not exactly our home, just a attractor of the atmospheric shell on its surface.

So, if life in a tiny fraction of the known universe is evidence of conditions being “just right,” what if instead we saw life on nearly all planets and moons that we could observe? What if the conditions between planets did not suffer from inadequate pressure, or wasn’t bitterly cold and rife with stellar radiation? Is that less likely to be “ideal for life”? Funny, I’d consider that to be much better evidence for the argument, myself. This is one of the problems with such arguments – they rely solely on the bare fact that we exist, not that this seems rare, common, limited or abundant.

One can assign many different numbers to the conditions we have now, and make them appear to support whatever standpoint we like – this is actually a cheap debating ploy. How many forms of life are visible on this planet? It numbers in the hundreds-of-thousands to millions just for suspected species, in the trillions-of-trillions if you’re counting individual occurrences (like bacteria.) But what is the percentage of matter sustaining ‘life” in our known solar system? So tiny it can barely be expressed, and in fact, cannot even be observed from more than a few hundred kilometers above the surface of our planet. What percentage of matter in the galaxy (not universe, mind you) is in conditions conducive to life? We have no freaking idea. So is this supportive of “ideal” or not? It’s easy to shift the influence of the argument simply by making leading statements, but this is only evidence of a lack of perspective.

There’s even more to the anthropic principle argument than this, however. Variations of the strong anthropic principle point out that the very nature of atomic physics, the four key forces that dictate how every last bit of matter forms, stays together, and behaves, are necessary for the universe as we know it to be here. Fractional changes of any one of these would mean that matter could not bind, gravity could not cause suns to coalesce, and planets would never form. Such things are just right to even make a universe as we know it – what are the chances? They must be so low as to be nonexistent.

First off, this is exactly the same as the weak anthropic principle – if such adverse conditions exist, or had they ever, there’s no way we would ever know about it, since we require those four known forces to be present before we can exist or function. We could make the same argument for light itself: without it, we wouldn’t be able to see anything! But plenty of species get by just fine without vision, and we evolved vision because that form of energy we call “visible light” is abundant. To say that it is “necessary” is arguing backwards – in areas where visible light is scarce, species have evolved other means of detecting their environment. And again, the wavelengths of electromagnetic radiation that we call visible light form a very narrow band of the spectrum of electromagnetism, of which we can detect virtually none on our own. Visible light just happens to be the most abundant to penetrate the atmosphere, so the easiest for most life forms here to take advantage of. We mostly ignore the other aspects because we don’t use them, but to then consider them insignificant in our calculations of “just right” is being incredibly self-centered.

Then there’s the “fractional differences” part of the argument: if gravity, or the strong atomic force et al, were just a teensy bit different, the universe wouldn’t be here. But we have no idea what kind of variation could occur, if any at all. We assign numbers to these forces, and can change the numbers, but this doesn’t mean the forces are changeable, nor does it mean such changes are either drastic or infinitesimal. We have never observed these being any different at all, nor even know where they came from. This doesn’t make them arbitrary. It’s kind of a nonsense argument, like supposing that unicorns exist and then breathlessly asking, “What are the chances?” Well, zero, to be honest.

No, that can’t be right, can it? But yes, it can, and this is where people constantly miss the boat. Orders of probability can only be calculated from things with known variables. You may have a one-in-six-million chance of winning the lottery, because that is the number of combinations possible from the little ping pong balls in the machine. However, if we have never observed any variations in something, there is only one order of probability able to be calculated, and that’s one-in-one, otherwise known as “guaranteed.” While this does not rule out something else actually being possible, it also doesn’t make it possible, and no order of probability can be assigned in the slightest. All we can do is speculate, and this relies solely on imagination, not on anything resembling science or mathematics in any way.

To then take such imaginative speculation and assign it a very low order of probability, and therefore claim that this is evidence of some higher being, is what we call sophistry at best – I myself call it utter bullshit. It’s not an argument, it’s a method of trying to justify a preconceived notion in an exceptionally pathetic way. We have never witnessed any variation in gravitational force based on mass either, which is good, because we use it for everything from weighing bananas to calculating successful orbits of planets and moons in our solar system (let me take this opportunity to give a shout out to Cassini.) Imagine if someone claimed that gravity could change any second, and we’d fly off into space, therefore we should all anchor ourselves firmly to the ground. We’d consider him an utter loon, wouldn’t we? But arguments such as, “if the universe was different, we wouldn’t be here, therefore god,” are just as fatuous. Pay attention, because this is one of the biggest failings of philosophy as I see it: the word “if” is not magical, and does not grant the possibility of existence. It is merely a factor in argument, pure imagination when you get right down to it. We only start talking about having real value when “if” becomes “when.”

There’s even another aspect that people continually misunderstand. Very low orders of probability, even if we have an accurate and useful way of calculating such, do not cross the line into “impossible” or into making a supernatural explanation even slightly more likely. If the chance of conditions being right for life were/are one-in-five-hundred-trillion, this doesn’t prevent it from having happened, and the weak anthropic principle argues that these are the only conditions we’d see if it did (again, “duh!”).

While we’re on the subject of abusing statistics and probabilities, there’s one aspect you’ll never see addressed: the probability of a supernatural, causative, and hyper/omnipotent being. If the chance of four forces being right for life is so low, how much lower is the chance for an extra-dimensional being with such inordinate powers? But this argument never rears its ugly head, for it is assumed that if an order of probability for random life is low enough, then a supernatural being becomes the default explanation. There is nothing that supports such an idea, however; no way that one can posit a “default” option. Even more interesting, if one allows for special conditions that give a supernatural being expansive powers and abilities, ones that we cannot witness or comprehend, such an argument can be applied to simple physical rules that shape the universe’s forces as well. This makes far more sense than a super potent being that nevertheless has thought processes so similar to our own.

It’s absolutely true that science does not have all the answers, and I’ll go out on a limb here and say that it never will. The mistake that is made constantly is believing that “we don’t know” is an opening for some other explanation such as “goddidit.” In fact, religious apologists (and countless vapor-brained new age nitwits) constantly remind us all to be humble and not assume that science can explain everything, never tumbling to the fact that they then attempt to explain things without even a vestige of evidence or reasoning – and worse, that these explanations all somehow put human beings in the bin of something special, rather than just another species on the planet. “We don’t know” doesn’t mean, “but we’re allowed to guess and consider it valid,” it means we don’t know. As we’ve demonstrated millions of times throughout history, the only way we find out is through careful examination, not wild-assed guesses based on emotional desires. Lightning is not from Zeus, Fulgora, or Tlaloc, and the claims in ages past that if we couldn’t explain it, then it must be one of those gods, certainly didn’t hold true. If we want answers, then we should seek them, not accept something because it’s convenient or self-validating. Life may or may not be exceptionally rare; the conditions that caused the creation of matter in the universe may or may not be highly unlikely. We cannot assign such properties without actually seeing some variation of them in the first place.

Clustered throughout most of the lower half are some of the more elaborate nebulae, including the Orion Nebula and the Horsehead Nebula, homes to brand new stars forming as you read this. Don’t bother running outside to watch it happen, since the nebulae aren’t visible to the naked eye, and star formation is a terribly slow process. The three belt stars, the very distinct line of stars almost vertical in this image, are truly just three stars – but the sword (ahem) stars visible nearby, dimmer and at a 45 angle, are entirely different. Looking like only three stars, binoculars or a low-power telescope will reveal there are actually many distinct stars in there; three in the middle, two at one end, three at the other. More resolving power will bring out many more – this is a neat thing about initial introductions to astronomy, since those blank spaces become stuffed with stars as you gain resolving power. And with a good scope, you can see the hidden secrets of Orion. Those sword stars are surrounded by the vast cloud of M42, the Orion Nebula. And in that cloud of gas and dust, we can see evidence that our speculations about the formation of planetary systems, like our own solar system, is accurate.

Source: Hubblesite.org

Or maybe not. The presence of other nearby stars could prevent that, or destroy it soon after beginning. The same conditions that make this nebula such a great region to see stars form also makes it less likely to produce the kind of planets we’d like to see: those capable of supporting life. Things are too crowded, and stars have some bad habits, like putting out huge amounts of powerful radiation and ending their lives rather spectacularly. Earth, brimming with life, exists in a special place in relation to our own star (we call it the “sun”) in that it is close enough to receive a certain amount of heat without getting overheated, and far enough not to have the oxygen/nitrogen atmosphere blown away by stellar winds. The atmosphere itself blocks a lot of the radiation that the sun hurls outward, so our delicate little bodies don’t get bombarded with Incredible-Hulk-producing gamma rays. Earth’s orbit is actually a “just right” distance for the size and nature of our sun, a place called the “habitable zone.”

Some maintain that the chances of this happening are so small as to be, literally, nonexistent, and that it was no accident that the Earth sits here. Statistically, this is utter nonsense – there are no probabilities that pass a certain point and become impossible. But the Earth can actually inhabit a broad band of orbital distances from our sun, broad enough that Mars almost sits within it – indeed, Mars shows signs that it once had an atmosphere. And bear in mind that the Earth’s orbit is elliptical, and it varies in distance form the sun by five million kilometers (three million miles) throughout the year. We can see how thoroughly this affects us here in the northern hemisphere by the fact that it’s the hottest when we’re the farthest from the sun (it’s the axial tilt of the Earth, and how both oblique angles and length of daily exposure affect the warming of the atmosphere, that makes our seasons.) There is nothing “too special” about Earth.

However, that little baby planet system up there might not be so lucky. Stars that are very big, or stars that are reaching the end of their lives, throw down some serious bad shit, a can of cosmic whupass that could take a protective atmosphere of gases and disperse it back into the nebula – our own sun will do that a few billion years from now (just not into the nebula, since we ourselves are not within one.) So having lots of stellar neighbors may not be so, um, stellar. It could mean that, just as life starts settling in and thinking of redecorating the ecosystem with more oxygen and carbon-exchanges, some big bad wolf huffs and puffs and blows the whole floating rock bare. Forever. Or at least until the home sun goes blooey itself and scours its orbiting system clean.

There’s a faint hint of it here in my shot showing just Orion’s Sword, corner to corner, but the brightest of those three stars making up the middle “star” of the sword is actually a cluster of stars itself, referred to as the Trapezium. The brightest of that cluster, called Theta1 Orionis C (or θ1 Ori C,) is our big bad wolf.

Source: Hubblesite.org

The timing of this is interesting, as well. The stars shown here had to have formed before θ1 Ori C reached its own strength, otherwise the stellar wind from it would almost certainly have prevented the coalescence of gases that eventually resulted in star formation. So this brash young upstart grew up in an established neighborhood and started wreaking havoc, driving the property values down for light years around. Now you know why homeowners’ associations exist. But don’t be too harsh on the lad, since the debris being blown away from those stars is exactly what can form life in other systems, as well – fused atoms of “heavier” elements that react much more readily to energy exchange at “low” temperatures, such as the kind we experience here on Earth. The spring wind destroys the puffball of the mature dandelion, but only succeeds in sowing those seeds elsewhere.

So, think about this the next time you’re gazing aloft on a cold clear night. That little speck of light in the middle features a maelstrom too tiny for our eyes to make out, but unbelievably vast in size nonetheless, and possibly seeding the surrounding emptiness with the building blocks of life. Most of the very atoms within our bodies went through conditions very similar, and will again, too. In fact, we haven’t the faintest way of determining if any part of us once resided within another lifeform from far away, billions of years ago. The possibility certainly exists.