Why Older Planets are more likely to Harbor Life

As long as humanity has been examining the celestial heavens, there has always been a keen curiosity about the existence of life on other planets. It’s not unfathomable to believe that in the vast area we call space there is sustainable life on other planets. A question often associated with life on other planets is where in the universe it might exist.

For centuries mankind has been seeking answers to the many questions that only outer space can answer, and waiting for technology to catch up so society can get some answers. And perhaps mankind is reaching a point where some of those answers may finally be uncovered. Two years ago the Kepler space telescope was sent into orbit and is steadily gathering data.

In the relatively short span of time, Kepler has identified more than 1,200 potential planets. The question is not whether or not many additional planets exist, it is a matter of finding one that has environmental conditions that would support life. What scientists are seeking is known as a ‘goldilocks’ planet. The ‘goldilocks’ scenario is a planet that aligns with the philosophy in the fairy tale “The Three Little Bears” where Goldilocks seeks the perfect conditions. In terms of planetary atmospheric conditions, this translates to ‘not too hot, not too cold, but just right’; a setting where the presence of liquid water can exist and sustainable life be present.

In addition to ideal temperature conditions, scientists cite another important factor when it comes to whether or not a planet can successfully harbor life, age. Age of planets, however, is very difficult to ascertain.

According to Time.com there may be some clues, as all planets are approximately the same age as the star they orbit, but even this does not necessarily yield conclusive answers in determining age. Scientists believe that slow-spinning stars with generally clear complexions suggest a mature solar system which can potentially harbor life due to certain conditions being present.

Time says: “In the biology game, planetary age can be everything. If alien astronomers had discovered Earth when it was just a billion years old, the only life they’d be able to find would be the most primitive of microbes. If they waited another billion years, they’d see the effects of cyanobacteria pumping oxygen into the atmosphere.”

The article continues “At about 4 billion, multicellular organisms would arise. And if the aliens wanted someone to talk to, they’d have to wait until Earth had been around for 4.6 billion years, when humans began communicating with radio signals.”

An article in Space.com also supports astronomers use age as being one of the important factors used to determine atmospheric conditions that can sustain life. The article states “Stars that were less than 3 billion years old are thought to be too young for planets and life to evolve.”

As a planet develops and ages to the point where it creates ideal conditions to harbor life, as these are discovered, it stands to logic that perhaps someday scientists may find the answers to the many questions mankind has about the universe.

The trick lies within determining which planets these are, and astronomers can perhaps find where to put focus in finding other life forms in the universe. Last year scientists found a planet that was found to be hopeful as a ‘goldilocks’ with the discovery of Gliese 581g. This discovery has been questioned and more studies will likely be conducted in the scientific community to resolve this controversy. 

However as science and technology progress, one day determining age of a planet may be as routine as other now known factors, and when this occurs, finding sustainable life on other planets may just become a reality.