Our Unique Planet

To be able to support life, a planet needs special galactic conditions, a special place within the galaxy, a certain type of star that it orbits at the right distance from it, a moon with the right size and distance, a certain tilt, mass, and element composition, a certain speed at which it rotates, and more. The planet earth has got it all!  

The Sun and the Milky Way 

·    The Milky Way is a spiral galaxy not in collision. 

·    The Sun is in a low concentration of stars. 

·    The galactic region has a high local density of metals. 

·    The Sun’s mass ensures a nominally constant energy output for at least 5 billion years. 

The Earth has: 

·    Sufficient metal elements from which the complex molecules of life can arise 

·    Relatively low carbon content – to avoid a heat-trapping CO₂-rich atmosphere 

·    Relatively low water content – to allow dry land as well as oceans 

·    Rotating molten iron-rich core to induce radiation-shielding magnetic field 

·    Mass which enables an oxygen-rich atmosphere (rather than hydrogen which is too reactive) 

·    Plate tectonics producing continental drift, mountain chains, diverse climates and therefore a diverse biosphere 

·    A nearly circular orbit enabling fairly constant solar input all year round 

·    Distance from the sun to enable sufficient warmth and light for photosynthesis but prevent tidal locking 

·    Huge planets on the outer edges of the planetary system to be shielded from devastating meteor impacts 

·    No huge planets nearby which would interfere with its orbit, gradually driving it into the sun 

·    Moderate tilt to ensure more uniform north-south distribution of solar radiation 

·    Short planetary rotation enabling all-around distribution of incoming solar radiation 

·    A large moon enabling tidal mixing 

Our universe and planet are special indeed. The likelihood of finding all the above-listed conditions – a life-supporting galaxy and solar system, as well as a life-nurturing planet – anywhere in the universe has been estimated to be one chance in 10¹⁸. With the estimated number of stars in the visible universe being about 10²², this means the possibility of about 10⁴ or 10,000 earth-like planets circling a sun-like star. With about 10¹¹ galaxies in the visible universe, there would be an average of one earth-like planet per 10 million galaxies! 

Our abode – this special “blue planet” – in the whole vast universe has all the markings of being the product of design – divine intervention in the development of life. 

Based on: God According to God, Chapter 3, by Gerald L. Schroeder (HarperOne, New York, 2009).

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