Monday, July 31, 2017

More Than Water Is Required for Life

A New Habitable Zone Discovered

The other day I saw an interesting article posted on entitled "More To Life Than The Habitable Zone." The "Habitable Zone" is the area around a star where a planet may exist with water in all three states. This is crucial for life's existence. In the article the team of scientists studying a particular star for habitable planets recognizes that the zone where water can exist is not the only area that limits where a life-destined planet may be found. The scientists explain that another factor that further limits that "habitable zone" is the amount of ultraviolet radiation emitted from the host star. Similar to the water habitable zone, the UV habitable zone is the area where the UV radiation is within the maximum and minimum bounds that permits life to exist. Both zones are necessary, so the only area where life can exist is the area where the two zones overlap each other. This area is so tiny that the team of scientists conclude that while a large portion of stars (red dwarfs) scientists have been investigating for habitable worlds are not completely off the table, it would be more prudent for scientists to focus efforts on the relatively few stars that more closely match our sun. Such a star would allow, presumably, for a larger overlapping area of the water habitable zone and the UV habitable zone.

Narrowing the Options

Astrophysicist Dr. Hugh Ross of Reasons to Believe describes these two habitable zones in his latest book "Improbable Planet: How Earth Became Humanity's Home." He also describes three other habitable zones that have been discovered. Not only is earth located in the water habitable zone and the UV habitable zone, but zones for photosynthesis, ozone, and tides also exist. This means that not only must the water and UV zones overlap, these other three must overlap as well. The only areas where overlap of all five exists are where a planet must exist around its host star to be a candidate for life.

A quick internet search reveals that red dwarfs make up roughly 70% of the stars in the universe. If the team of astrobiologists are saying that the recognition of just one more habitable zone limits the candidate sites in the universe (practically rules out an entire class of stars) by 70%, then how much more will the recognition of these extra three zones limit the possible locations for life? Even though research is revealing a more precise target for where life can exist (thus focusing expensive research time and resources), the number of physical locations available for life to originate are being dramatically reduced. While the universe is huge and scientists already recognize that the majority of it is not viable for life's existence (nowhere near a star), this team of scientists has ruled out 70% of the space already left.

But that's not all. To further focus our research efforts (but reduce the areas for life), two more (non-location) habitable zones exist: the planet's rotation rate and obliquity. Each of these affect the other five zones in different ways, so while one zone may be widened or move closer to the star, another may be narrowed or move further from the star. When the planet's rotation rate and obliquity are taken into account as well, the actual area where a planet may exist and support life becomes even smaller or disappears completely for even more stars.

An Ancient Universe and Evidence for Design

As research continues, the history of our planet is becoming more of a problem for anyone who thinks that life is ubiquitous in the universe. Not only that, the more research continues, the more the history of our planet resembles a complicated project executed for a purpose- a project that includes numerous phases with numerous concurrent and necessary events that, if not started and finished at the proper time, would doom the project to failure. The longer the history of our planet, the longer the project and the more of these complicated phases there are. While many people think that an ancient universe provides naturalists a legitimate reason to deny the need for a Designer, the evidence provided by this ancient universe is revealing the exact opposite: that a Designer is necessary to explain why our planet and its history appear to be designed. The ancient universe is quickly becoming an unstoppable evidential force, declaring the glory of its Creator (Psalm 19:1) and leaving educated unbelievers with even less excuse for rejection (Romans 1).

Dr. Hugh Ross has also posted on this discovery: Inability of Planets Orbiting Red Dwarfs

To Go Deeper, I Recommend These Books:


  1. Very well written Luke. I would have expected head way on the multiple habitable zones to be more accepted among academics, but I suppose like all people the idealogical sunk costs are hard to over come.

  2. Good stuff. And when you take into account that only a small number of galaxies are "candidates" for life...ditto for percentage of locations within a galaxy...and ditto for entire galaxy clusters (!) the number of potential star candidates shrinks to an incredible degree. And the more we learn the numbers continue to move in the lower direction.


****Please read my UPDATED post Comments Now Open before posting a comment.****