NASA launched the Kepler telescope in 2009 to “find terrestrial planets . . . especially those in the habitable zone of their stars where liquid water and possibly life might exist.”1 Kepler has now been collecting data long enough for scientists to confirm the existence of at least 35 of the 2326 possible planets it has pinpointed, and the roster is growing rapidly. Tatooine-like planets with binary suns2 and the tiniest known solar system made big news this month, even eclipsing the discovery of moon-ice.3 Last month saw the confirmation of a planet with 2.4 times Earth’s radius in the habitable zone; though its mass, composition, and the possibility of an atmosphere have yet to be determined. Close on the heels of that discovery came the announcement of two Earth-sized planets too hot for life. The latest headliners are also too hot to be habitable, but statistical possibilities have raised evolutionary expectations that alien life may yet await our acquaintance.
A terrestrial planet is defined as “one half to twice the size of the Earth.”4 Such small planets are generally rocky. To be in the “habitable zone,” an exoplanet must be neither too hot nor too cold for liquid water to exist and have the potential for holding onto an atmosphere. The presence of an atmosphere cannot yet be determined for exoplanets, and atmospheric components would be a key factor in maintaining Earth-like temperatures. From an evolutionary point of view, where there is water, life as we know it could have evolved.
NASA scientists mapping the dark of the moon5 think lunar dirt in permanently shadowed regions may contain—in frozen form—more water than Sahara sand. But Kepler dominates the headlines, and the reason may involve more than just the excitement superlatives generate. After all, we already went to the moon and found it devoid of life.
For Star Wars fans, Kepler’s confirmation that binary stars actually can have planets in stable orbits is pretty exciting. Regarding the confirmation that Kepler 16b, Kepler 34b, and Kepler 35b are all genuine circumbinary planets, astronomer William Walsh, author of the announcement in Nature, says, “The fact that circumbinary planets are not rare flukes means that nature likes to form planets, and can and does form planets around binary stars, even though these are very dynamic and chaotic environments. And more planets mean more chances that some will be Earthlike. . . . The search for Earthlike planets can now include the binary star systems.”6
Circumbinary planets “can have really crazy climates,” says co-author Jerome Orosz. “It would be like cycling through all four seasons many times per year, with huge temperature changes.” Walsh adds, “The effects of these climate swings on the atmospheric dynamics, and ultimately on the evolution of life on habitable circumbinary planets, is a fascinating topic that we are just beginning to explore.”7
The Lilliputian solar system’s size—only 5 million kilometers across—is more on the scale of “Jupiter and its moons than to a sunlike star with orbiting planets.”8 All three are much smaller than Earth. Like the “Tatooines,” the three little planets orbiting close to the small red dwarf known as “Kepler Object of Interest-961” are too hot for life. Nevertheless, Cal Tech’s John Johnson believes odds favor the future. “Because red dwarfs themselves are so common,” Johnson says, “the whole galaxy must be just swarming with little habitable planets around faint red dwarfs.”9
Since red dwarfs are our galaxy’s most common type of star, the discovery that this one has small planets suggests to UC Berkeley’s Geoffrey Marcy “that rocky planets are common and diverse, and that our Solar System is not some cosmic quirk composed of weirdo worlds.”10 MIT astronomer Sara Seager comments, “We need to get a census of how many rocky planets are out there to understand how Earth formed, and how common life may be in the Milky Way.”11 The possibility that Earth may not be as unique as previously thought pleases those hoping to find extraterrestrial life.
Kepler detects planets using the transit method, noting the periodic dimming of stars as planets pass in front of them. Exoplanets are also detected by noting the wobble of a star due to the gravitational tug of planets. A new method using the light of one star to backlight another—gravitational microlensing—will further increase exoplanet detection. Each method works best for planets of particular sizes and orbital distances. A planet’s size is determined by comparison to its star’s size. In fact, the small size of the planets orbiting KOI-961 was discovered after the red dwarf star was found to be smaller than originally thought.
Statistically speaking, Jørgensen believes the Milky Way must have at least 10 billion habitable planets.
These three methods complement each other and thereby should greatly increase the number of detectable exoplanets, particularly habitable ones. Microlensing expert Uffe Gråe Jørgensen stated,“Together, the three methods are, for the first time, able to say something about how common our own solar system is, as well as how many stars appear to have Earth-size planets in the orbital area where liquid water could, in principle, exist as lakes, rivers and oceans—that is to say, where life as we know it from Earth could exist.” 12 Statistically speaking, Jørgensen believes the Milky Way must have at least 10 billion habitable planets.
Believing the universe and its many solar systems formed through random processes billions of years ago, most evolutionary cosmologists believe in the inevitability of the possible. Astronomer Virginia Trimble asserts, “Everything not forbidden is compulsory. Any kind of system you can think of, if it doesn’t violate the laws of nature, it probably exists somewhere out there.”13 In other words, if something could happen, it must have happened. Therefore, there must be lots of habitable planets, and surely, evolutionists surmise, some are inhabited.
Many think the existence of water and organic chemicals in the same place for long enough under “habitable” conditions must produce life. Jørgensen thinks life as we know it is unlikely but only because “so many unique events . . . created the basis for the development of life on Earth. Comets brought water to our planet so that life could arise and a series of random events set in motion an evolution that lead to humans and intelligent life. It is very unlikely that the same circumstances would be present in other solar systems. . . . Perhaps other coincidences in other solar systems have led to entirely different and exciting new forms of life.”14
God’s Word tells us He created the sun, moon, stars, Earth, and all life on Earth during the first six days of Creation Week about 6,000 years ago. Comets did not seed the Earth with water; God created water on Earth at the beginning of Creation Week. Scientists cannot test and observe past events or overthrow God’s eyewitness account. Neither mankind nor the universe is a result of random processes.
Therefore, if life were to be indisputably found on another world, its existence would not confirm molecules-to-man evolution. Such life would simply be another demonstration of God’s power to create life where He chooses.
Scientists have never observed life evolve from non-living components. Thus, finding the right chemicals and conditions for life to exist elsewhere should not suggest it has. The Bible does not say that God didn’t create life elsewhere. However, “
without Him nothing was made that was made” (John 1:3). Therefore, if life were to be indisputably found on another world, its existence would not confirm molecules-to-man evolution. Such life would simply be another demonstration of God’s power to create life where He chooses.
The diversity of exoplanet discoveries declares the glory of the God (Psalm 19:1) who created them. But these discoveries do not demonstrate that whatever could randomly happen did happen—cosmologically or biologically. (Besides, the big bang and the nebular hypothesis actually do violate the known laws of physics.) 15 Exoplanets are observable in the present. Despite an assertion that “finding a multitude of rocky, Mars-sized exoplanets may help shed light on a long-standing problem in understanding the formation of [our] inner Solar System,”16 observations made in the present cannot confirm assertions about the origin of the universe’s solar systems.
God’s eyewitness account in the Bible doesn’t spend a lot of ink on the origin of the rest of the universe but sums it up saying, on the fourth day, after making the sun and moon, “
He made the stars also” (Genesis 1:16). God knows how many stars He made, and He has even named them (Psalm 147:4). With our growing technology, we can gain appreciation for the diversity of the universe He created. Whether Earth’s solar system appears unique or not, ours is the world in which God placed Adam and Eve and to which He sent His Son Jesus Christ to redeem rebellious humans. The existence of Earth and human beings is not the result of random probabilities and evolutionary accidents but a product of God’s plan from before the foundation of the world (1 Peter 1:20).
See the following articles for more information about exoplanets:
- Looking for life in all the right places
- The Kepler planet-hunting team
- Astronomers may soon find more “Earth-like” planets—and with them, alien life?
- Exoplanets—Unpredictable Patterns
- Five More Earths?
See the following articles for more information about alien life: