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How Far is Far?
If you’re a fan of Astronomy, then you may already know that the
Hubble Telescope, utilizing its recently refurbished instruments,
recently stretched its outer limits and recorded the furthest objects
ever seen, or in this case, digitally imaged. Employing its
newest toy, the infrared Wide Field Camera, the Hubble detected a group
of primordial galaxies near the limits of the observable
universe. The images (See graphic) show these ancient formations
at the outskirts of what is believed to be a universe that reaches out
to over thirteen billion light-years. More fascinating still, is
that these splotches of light are seen as they appeared approximately
700 million years after the birth of the universe, in what astronomers
refer to as the big bang.
At that time, these compact blue galaxies defined the edge of the Universe which was less than a billion light-years in size. As time marched forward, the universe expanded into the 13 billion light-year behemoth we are familiar with today. Even in astronomical terms, this is a ridiculously huge space, both in distance and in time. The further away objects are seen, the farther back into time we get to witness. In essence, the Hubble is not just a telescope, but like all telescopes, a sort of astronomical time machine. The Hubble, though, has earned the Big Dog Crown!
The objects recorded in the accompanying NASA graphic are no longer there. They may have evolved into new generations of galaxies, or completely fizzled out eons ago. What we see in these images are how these earliest objects appeared back near the boundary of time itself. In the big bang theory, time and space and matter each came into existence in the now famous cataclysmic explosion, thirteen billion or so years ago.
At that time, these compact blue galaxies defined the edge of the Universe which was less than a billion light-years in size. As time marched forward, the universe expanded into the 13 billion light-year behemoth we are familiar with today. Even in astronomical terms, this is a ridiculously huge space, both in distance and in time. The further away objects are seen, the farther back into time we get to witness. In essence, the Hubble is not just a telescope, but like all telescopes, a sort of astronomical time machine. The Hubble, though, has earned the Big Dog Crown!
The objects recorded in the accompanying NASA graphic are no longer there. They may have evolved into new generations of galaxies, or completely fizzled out eons ago. What we see in these images are how these earliest objects appeared back near the boundary of time itself. In the big bang theory, time and space and matter each came into existence in the now famous cataclysmic explosion, thirteen billion or so years ago.
As recently as the mid twentieth century, the three opposing cosmological views were first, the Closed View. It states that the universe is stagnant, where new matter is being created "somewhere" to replace the matter that eventually disappears. The second view proposes that the universe is open-ended and doesn’t contain enough matter, and therefore, the gravitational force needed to halt its observed and proven expansion. This would result in an ever growing universe, one that would continue to expand forever until at some distant epoch everything we see today would have drifted away to unimaginable distances and eventually, blink out of existence. If you’re not aware of the fact, all matter will eventually disappear. Scientists have actually performed experiments that show this happening, albeit on an atomic level. Matter is continually blinking out of existence.
A third theory which has been championed by several notables, proposed that hidden or dark matter undetectable with our current instruments would indeed provide enough gravity to cause the expansion of the universe to stop, and perhaps even collapse upon itself and revisit the Big Bang - the Oscillating Universe Theory.
Throughout history, man has wondered and debated what kind of Universe we live in. Today, "weighing" the Universe is done to determine whether or not it does indeed contain enough matter to halt the expansion, or as some have proposed, includes secret, undetectable places where dark or hidden matter exists, or where matter is continually being created. As notable as the “Hubble Time Machine” has been, newer, more advanced instruments are scouring the Universe today and peering deeper and further back into time and space than man has ever been. What lies beyond? Are other civilizations, somewhere we’ve not yet discovered, asking the same questions as we are? Have they learned things we’ve not yet realized? Only time will tell. As we continue to study the Universe, we’ll continue to learn that there is more than meets they eye, or in this case, more than meets our orbiting astronomical platform-based detectors. The story is hardly over and I am certain that we've still plenty to discover and learn about ourselves and our surroundings.
Lastly, like the Hubble, this month we all get to jump into a time machine of sorts, as we “spring ahead” on March 14th. The big reveal so to speak, is that Sunset, on the 13th will be at quarter to six in the evening. However, almost magically, on the 14th, it will not set till quarter to seven. Before you know it, snow and ice encrusted Lawnchairs everywhere will begin to thaw and find themselves glistening once again, in the late evening sunshine.
Clear Skies!
The Lawnchair Astronomer
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