The weekend gets off to a beautiful start tomorrow — if you’re an early riser. The Moon and the planet Venus — the “morning star” — team up before and during dawn. They climb into good view by two or three hours before sunrise. And as twilight paints the sky, they’re well up in the southeast.

The Moon is the major factor that controls ocean tides here on Earth. And a recent study found that it also plays a big role in controlling the health of some mangrove forests.

Mangroves are found along many of the world’s coastlines. They form thickets that prevent erosion during tropical cyclones, and provide shelter for fish, turtles, and other life. They also store carbon dioxide, helping to limit global warming. But they face a lot of threats — from coastal development to higher sea levels.

The study found that the Moon both helps and hurts mangrove forests, over a cycle of 18.6 years. That coincides with a natural “wobble” in the Moon’s orbit. The change in the Moon’s angle can led to especially high high tides, and especially low low tides, at some locations — including a bay along the northern coast of Australia.

Researchers found that the mangroves there were especially verdant at certain times, then especially puny about nine years later, then healthy again nine years after that. So the health of the forests appears to be influenced by the Moon — as it “wobbles” around Planet Earth.
 

Script by Damond Benningfield

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