It’s an instance of fine-tuning:
Earth’s moon is vitally important in making Earth the planet we know today: The moon controls the length of the day and ocean tides, which affect the biological cycles of lifeforms on our planet. The moon also contributes to Earth’s climate by stabilizing Earth’s spin axis, offering an ideal environment for life to develop and evolve.
Because the moon is so important to life on Earth, scientists conjecture that a moon may be a potentially beneficial feature in harboring life on other planets. Most planets have moons, but Earth’s moon is distinct in that it is large compared to the size of Earth; the moon’s radius is larger than a quarter of Earth’s radius, a much larger ratio than most moons to their planets. p1 Miki Nakajima, an assistant professor of earth and environmental sciences at the University of Rochester, finds that distinction significant. And in a new study that she led, published in Nature Communications, she and her colleagues at the Tokyo Institute of Technology and the University of Arizona examine moon formations and conclude that only certain types of planets can form moons that are large in respect to their host planets…
The researchers found that rocky planets larger than six times the mass of Earth (6M) and icy planets larger than one Earth mass (1M) produce fully—rather than partially—vaporized disks, and these fully-vaporized disks are not capable of forming fractionally large moons.University of Rochester, “Moons may yield clues to what makes planets habitable” at Phys.org (February 1, 2022)
The paper is open access.
You may also wish to read: What becomes of science when the evidence does not matter?
4 Replies to “Researchers: Moons make planets habitable — but not all planets can have them”
This has no bearing on “evolution”, an equally failed theory on Earth as on Mars, etc. With or without liquid water available.
This doesn’t seem likely. A better question would focus on the variables that cause cycles. Earth has seasons because of a tilted axis. Earth has days because it rotates. The moon and stars give us more subtle cycles, all of which are used by some types of life.
This question does lead easily to a test of one hypothesis about life.
If we assume that life started in those deep volcanic vents, it would never have a reason to experience seasons or days or moon phases. If that’s the case, why are internal clocks crucial to all levels of life? Why does the genome include clocks if they weren’t needed at first?
The Moon stabilizes our rotation. Making life possible
Scientists can’t even figure out where our moon came from. Best guess is some kind of a fortuitous collision with earth and an asteroid of some sort. But the angle and speed would have had to be “just right” in order to result in a moon. Whenever astronomers can’t figure something out, they just conjure up an asteroid collision and problem solved. It’s just like saying “It evolved.” It’s so easy. No one can prove you wrong (or right for that matter, but who cares?)
So how did the moons on all of these other planets form? More fortuitous collisions? Hmmm.
How scientific is that?