This article appeared in the August 21, 2018 edition of the Monitor Daily.

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A cosmic view shaped by water

David Clark Scott
Audience Engagement Editor

Water, water, everywhere.

A group of astronomers studied 4,000 known exoplanets (those are the planets orbiting a star outside our solar system), and they found that more than one-third were water worlds. In some cases, as much as half of the weight of these planets is water. (By comparison, Earth is only 0.02 percent water by weight.)

So water – and the potential for life – is far more abundant than many expected. Why is that surprising? Well, what we see in our own neighborhood, or in our own narrow experience, tends to shape our perceptions of reality. In this case, looking at the relative paucity of water in our solar system, we might be tempted to draw the conclusion that water is rare. But it turns out that we may be living in a cosmic Sahara – with Earth as an oasis – but elsewhere in the universe the norm is aquatic wonderlands. Of course, even within our solar system, we’ve started to find signs of more water on Mars, on our moon, and on the moons of Jupiter and Saturn.

Why does this matter?

First, it makes obsolete the scary movie plots in which aliens invade Earth for our water (a la “Battle: Los Angeles” in 2011). Clearly, there are plenty of better options out there.

But seriously, if water is one of the key ingredients for life, then life may be way more abundant than our own solar system suggests. And that’s a whole new way of looking at our universe.

Now to our five selected stories, including the pursuit of justice in the US, possible paths to stability between Israel and Gaza, and funding compassion with the US farm bill.

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This article appeared in the August 21, 2018 edition of the Monitor Daily.

Read 08/21 edition