When I was a kid, my mom bought both my brother and I a copy of National Geographic’s Picture Atlas of Our Universe (after which I’ve named this blog series). It was a fascinating book and examined each of the planets of our solar system in detail, complete with pictures and statistics. I read that book so many times that I could quote some of the details of it. Both my brother and I still fondly remember it.

As science and astronomy have gotten better, scientists have also come to recognize that in addition to how finely tuned our universe is for life, so also is our solar system finely tuned.

Consider Jupiter. Jupiter was my favorite planet in the Our Universe book and still is. I really think the planet is beautiful. It’s the largest planet in our system, a gas giant, and has 67 moons that they have discovered so far. It is so big that all the other planets of our solar system could fit inside it. It is so big that more than 1,300 of our planet Earth could fit inside it. And even for as massive as it is, its planetary rotation is much faster than ours on Earth. A “day” on Jupiter is 10 hours, compared to our 24. It has a storm that they’ve been tracking for the past 186+ years that is 3 times larger than our planet Earth. And the information that we know about it should get richer with the Juno Probe that NASA sent to it, which recently arrived in the vicinity, where they plan on sending it into Jupiter’s atmosphere to gather data. I’m trying to pay attention to that with great detail.

But something else is interesting about Jupiter as well. Scientists have come to realize that having a planet like Jupiter as part of the outer planets of a system is one of the important keys to for advanced life to exist on a planet like ours. J. Warner Wallace, in his book God’s Crime Scene: A Cold-Case Detective Examines the Evidence for a Divinely Created Universe, sums it up like this:

Our multi-planet solar system makes life possible here on Earth. The large gas giants orbiting the sun protect the Earth from hazardous cosmic materials. Jupiter, for example, helps “clean out” the solar system. Its incredible gravitational field redirects asteroids and cosmic debris, making the entire system more habitable.

In his footnotes, he then quotes theoretical physicist Michio Kaku

The presence of the planet Jupiter in our solar system is a fortuitous one for life on Earth, because its immense gravity helps to fling asteroids into outer space. If Jupiter were much smaller and its gravity much weaker, then our solar system would still be full of the debris of asteroids and comets left over from its creation.

Astrophysicist Hugh Ross explains it further detail. He says that if Jupiter’s distance from the Earth was greater, then too many asteroids and comet collisions would occur on Earth, and if Jupiter’s distance from the Earth was less, then Jupiter’s presence would too radically disturb or prevent the formation of Earth. He further says that if Jupiter’s mass were greater, Earth’s orbit would become unstable and that Jupiter’s presence would too radically disturb or prevent the formation of Earth. And if Jupiter’s mass were less, too many asteroid and comet collisions would occur on Earth.

But it’s not just Jupiter that is important. Even Neptune and the Kupiter asteroid belt beyond it are important. Also, the distance between our inner planets (Mercury, Venus, Earth, and Mars), the mass of Neptune to Jupiter, and more. All in all, Hugh Ross has identified 137 parameters that each have to fall within a required range for advanced life to exist in a solar system. The probability for all 137 parameters to occur in a solar system 1 in 10^112 (1o to the power of 112)!

Even the Sun, the star of our solar system has to be just right. 90% of the known stars are smaller than our Sun. Stars smaller than our Sun are problematic for life. Earth resides in the Circumstellar Habitable Zone with our sun. This means that if our planet’s orbit was 5% closer to the Sun, it would be too hot, causing our planet to more resemble Venus than as it is now, which would prevent advanced life from forming. And if our planet’s orbit were 20% further away, it would cause our planet to be colder and to more resemble Mars than it is now, which would prevent advanced life from forming. For the planet to reside in the Circumstellar Habitable Zone of a smaller star, it has to be closer to the star, which puts it at a stronger influence of the gravity of the star, slowing the rotation of the planet, which would prevent advanced life from forming.

Other stars are more massive than our Sun. The largest known star, VY Canis Majoris, if it were to reside in our solar system, it would engulf the orbit of Jupiter!

J. Warner Wallace sums up some of the important characteristics of our Sun in his book God’s Crime Scene:

Our star produces triamotic hydrogen at just the right quantity to create the essential molecules necessary to form planets. It also has a sufficiently high metallic composition to provide the heavy metals necessary for our planet without over-radiating or poisoning our planet. In addition, the color of our sun (not too red and not too blue) allows for photosynthesis. The sun is also bright and warm enough to allow carbon-based life-forms to exist. Unlike most other systems, our solar system has a single star. Multiple star arrangements cause a number of problems related to gravitational forces, tide cycles, and overheating.

The age of our sun is perfectly suited for the existence of life on Earth. If the sun were older or younger, its luminosity would be far too unstable to support life. Our sun is in the middle of its life cycle. It burns without extreme fluctuations and contains just the right amounts of heavy elements. its mass and gravitational attraction are also within narrow, life-permitting ranges. If our sun were any more massive, it would burn too rapidly and too erratically; any less massive, and a number of gravitational problems would result. Earth would have to be much closer to remain in orbit, and the impact on our climate, tides, and rotation would be devastating.

Hugh Ross says that there are 140 parameters for a star that each have to fall within a required range for advanced life to exist. The probability that such a star would occur is 1 in 10^108 (10 to the power of 108)!

All in all, even a solar system has to be fine-tuned for advanced life to exist. And we still haven’t even gotten to the Galactic Habitable Zone or the fine-tuning of a planet that is required for advanced life to exist. (More on both of these to come in future blog posts.) In consideration of the fine-tuning of a solar system and of a galaxy that is necessary for advanced life to exist, Hugh Ross has compiled a list of 402 quantifiable characteristics that must fall within narrow ranges. A slight increase or decrease in the value of each characteristic would impact that possibility.

I’d also recommend watching The Privileged Planet by astrophysicist Guillermo Gonzalez.