Nova: Finding Life Beyond Earth (Blu-ray Review)14 Jan, 2012 By: John Latchem
$24.99 DVD, $29.99 Blu-ray
Given man’s fascination with pondering “Are we alone?”, there certainly is no shortage of documentaries seeking to answer that question. This two-part “Nova” special doesn’t break much new ground in that regard, but it does update the template with some of the latest findings from scientists and astronomers.
Typically for “Nova,” this is dry science right down the middle. There aren’t discussions about UFOs or strange aliens revealing themselves to us. Instead, the focus is on the conditions that can facilitate the emergence of life and the likelihood of finding such a world beyond Earth.
While the universe may not be as rich in life as depicted on shows such as “Star Trek,” where aliens seem to have popped up on every other world, there’s still a vast universe of potential life taking shape in ways we can scarcely imagine.
The program does an excellent job breaking down the subject into easy-to-understand explanations, so viewers won’t need a Ph.D. to follow along.
The crux of the search is finding three basic building blocks for sustaining life. First, a system requires the right chemical mix, such as hydrogen, nitrogen, oxygen and organic elements such as carbon. Then, a planet would need large supplies of liquids for the molecules to interact and evolve. Finally, the place would need an energy source, such as heat from a star, to power the necessary chemical reactions.
Earth is ideal for life because all these factors are present in abundance. But Earth also benefits from the presence of planets and other objects in the solar system, such as comets and our moon. To see how Earth got so lucky, the show vividly re-creates the early years of the solar system, a chaotic period of particles of matter violently slamming into each other to form proto-planets and other heavenly bodies. At one point, proto-Earth was a lifeless mass of molten rock, until a smaller planet crashed into it, depositing vital minerals and helping to form the moon. The alignment of new planets caused unique gravitational reactions that sent comets hurling toward our young world, potentially bringing those first organic compounds that became the first proteins.
The second half tends to repeat information from the first, but with a slightly different spin. For example, the first part details the conditions found on Saturn’s moon Titan, while the second part offers some ideas about how life could evolve in the oceans of liquid methane that were found there.
The odds of such a specific combination of factors producing life on Earth seems to be extraordinary, but the conditions that could potentially produce life are certainly not unique to our planet. Within our own solar system are countless worlds where life may have potentially evolved if not for a slight adjustment here or there. By profiling such near-misses, we get a better appreciation of just how special our own world really is.