Microwave background radiation variation of the visible Universe, as observed by the Wilkinson Microwave Anisotropy Probe (WMAP). From the NASA/WMAP Science Team, via Wikimedia Commons.
I tend to focus on the terrestrial side of things here at Superoceras. Which is perfectly ok with me, Earth being such a dynamic, active planet. But beyond our tiny blue sphere is a vast and timeless Universe, the scope of which one can only begin to imagine (the best way to do so, in my opinion, is by walking along the "Scales of the Universe" exhibit at the Rose Center for Earth and Space at the American Museum of Natural History in New York). The Universe is bigger and older than most can even fathom, and recently, it seems like I've been hearing quite a bit about it in the news. Maybe it's time to branch out a bit and talk about some of the papers I've recently come across in regards to events beyond our planet, with a little background added for flavor.
Most cosmologists believe the Universe to have had an origin around 13.7 billion years ago (bya) with an event known as the Big Bang. According to this theory or model, the entire contents of the Universe were condensed in a very small, very hot, very dense state. With a violent explosion, the contents of the Universe began to expand rapidly, cooling along the way, and forming everything we see and know, from gravity and the electronuclear forces, to the matter and energy that make up the stars, planets, and even ourselves. It is believed that this expansion will continue until the Universe reaches it's maximum size, at which point it will begin to collapse again becoming very small, very hot, and very dense again in an event referred to as the Big Crunch.
Enter the first paper of the day. I'll admit there is a lot of technical talk in the paper that is beyond my current scope, but it is exciting nonetheless. It expands even further on the Big Bang model of the Universe through analysis of cosmic microwave background (CMB) radiation seen in the image at the beginning of this post. The researchers discovered circular patterns that mark lower than average temperature variations in the CMB (see Figure 3 from the Penrose & Gurzadyan 2010 at left). They believe these circles to be gravitational waves formed by the collision of supermassive black holes. This seems reasonable, but there is a catch. The ripples would have been formed before the Big Bang. Based on these findings, they proposed that the circles are indicative of the existence of an aeon (or aeons) preceding the Big Bang - a time before time as we know it. This would mean that the event that created the Universe we currently call home was only one event in a continual cycle of expansions and collapses of other universes before it (Gurzadyan & Penrose 2010). Wow.
In a lot of ways, most human beings exist in a reality where time is measured in hours and years, and the farthest distance we can hope to experience is a trip around the globe. We can't comprehend the true vastness of time and space. I know. I've tried. It makes sense on paper, but when I really attempt to wrap my mind around it, I'm always left overwhelmed. The idea of there being a time and place before the Big Bang is even more remarkable. And this remarkable claim has to be backed by remarkable evidence. This paper is a first step, but I'm eager to see what research stems from it. If nothing else, I'd like to see some more highly detailed CMB maps in the future.
Let's scale down from the Universe on the whole and take a glimpse at some of the things in it, specifically stars. Powered by the thermonuclear fusion of hydrogen for at least a portion of its life, a star is, at its most basic level, a giant ball of plasma held together by gravity. They coalesce from molecular clouds and stellar nebulae, and during the course of their life (or at the time of their death) produce most of the naturally occuring elements we know of. The closest star to Earth is the Sun, which appears in the daytime sky as a rather large object. The rest of the stars we can see with our eyes, from blue giants to red dwarfs, appear as tiny specs of light in the nighttime sky. If you live in an area without a lot of light pollution, you may be lucky enough to see a cloudy looking band of white light that stretches across the celestial sphere - our own Milky Way Galaxy.
Man made devices like the Hubble Space Telescope have been providing images of stars, and the galaxies they reside in, not visible to the human eye for the last two decades. The image at right, known as the Hubble Ultra Deep Field (from NASA and the ESA, edited by Noodle snacks, from Wikimedia Commons) contains approximately 10,000 of these galaxies, each of which could contain anywhere from tens of millions to trillions of stars, depending on its size.
Enter our next paper. In it, astronomers take a closer look at some nearby elliptical galaxies. These galaxies are chock full of luminous stars. This is a fact that would come as no surprise to the authors of the paper (or anyone who had read the previous paragraph). But what they did discover was an abundance of low mass stars that aren't easily seen because of the faint amounts of light they emit. Based on the discovery of these never before detected stars, they have extrapolated that the number of these low-mass stars may be so great in many of the galaxies we see, that the total number of stars in the sky could be up to three times as great as previously thought (Conroy & van Dokkum 2010). Three times! Wow again.
This is a remarkable claim, and as usual, the standard scientific caveat applies to this paper. As our technologies grow ever more sophisticated, we're able to peer deeper into deeper into outer (and inner) space, and see things I'm sure many never imagined possible. This is fundamental to the scientific process. As our knowledge base expands, that knowledge can be integrated to the understanding we currently hold. We can refine hypothesis, correct existing theories, and work towards a better understanding of the Universe. Many are critical of science and scientists for all of the "back and forth" (e. g., according to study A, eggs are good for you one day, but study B says they are bad for you the next). This isn't because scientists cannot be trusted, but rather, because as they learn about the Universe, they not only share their knowledge, but ask new questions, seek new answers, and discover new things in the process. The scientific process is a nearly endless cycle of gathering information from observations, and is by far one of the most powerful tools that we as human beings have access to.
Unfortunately, it's likely we'll never be able to see to the edge of the Universe, look back to the beginning of time, or count every star in the sky. At least not in this lifetime. But these recent discoveries are extremely interesting, and worthy of continued inquiry. The Universe is a big place, full of wonders and sights beyond imagination. And every day, we're learning new things about it. That being said, be on the lookout for future editions of "Beyond Earth" here at Superoceras.
Gurzadyan, V. G. and Penrose, R. 2010. Concentric circles in WMAP data may providde evidence of violent pre-Big Bang activity. Posted at arXiv.org on November 17, 2010.arXiv:1011.3706v1
Conroy, C. & van Dokkum, P. G. 2010. A substantial population of low-mass stars in luminous elliptical galaxies. Nature doi: 10. 1038/nature09578