Objects in the Night Sky

What We See vs What It Means

On a new moon night in December, the sky is at its deepest dark. Abyssal, endless.

Except when it is not. Night follows in the vein of day, and the day before this night was crystalline. Distant mountain ranges showed jagged glacial lines, the peaks of the Cascades and the Olympics so new, they are still pushing up out of the Earth.

Sun has set on this unexpectedly clear December day, no water in the air, no discernible particles, and yet the sky holds light. There is glow on the horizon from far away city lights. Closer in, there are planes, and lights from people’s homes. Farther away, satellites circle.

And we sit, lit inside by only a wood fire, as the stars become visible.

This is no typical Winter night sky. All of the cosmos is on display.

One object, brighter than all the rest, appears above the eastern horizon, yellow and pale.

It does not move at the speed of something humans have made. It is not a plane, nor a satellite. And it is too bright to be a star.

A planet, then, but which one?

It is too high in the sky to be Mercury, too far from the sun to be Venus, not red enough to be Mars.

That leaves Jupiter, or Saturn. The others are too far away.

We use objects that seem wildly insufficient for the task to help us diagnose our planet. Binoculars with 10x magnification bring us closer, but they don’t add much detail to that plain, bright, pale yellow disk.

Galileo designed a telescope with 20x magnification, with which he first saw the four largest moons of Jupiter. The Galilean moons. They circle the great gas giant, Jupiter, the Roman sky and thunder god whose Greek counterpart is Zeus. The Galilean moons are named for lovers of Zeus: Io, Ganymede, Callisto, and Europa.

As we continue to look, perhaps there is resolution. I see a fatness around the middle of our planet, a regularity, which I believe to be rings.

“It is Saturn,” I proclaim.

“I think I see moons,” he says. “It is Jupiter.”

We watch our fire, and the changing sky, and the slow movement of that giant planet in the night sky. We do not consult experts. There will always be time for that. Whichever planet this is, we can find out tomorrow. For now, let us watch, and think, and consider.

Hours later, the bright planet has yielded no more secrets. Our lenses are not quite powerful enough to discern the truth. I think I have seen rings, and so rings are difficult to unsee. He thinks he has seen moons, and so moons are difficult to unsee. One of us is not seeing accurately. Both of us are looking at the very same thing.

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The next morning dawns with atmospheric clarity again. The only planet still visible is the one on which we live.

We look it up. There were many planets visible in our night sky the night before. Had we been looking West, we might well have seen Venus. Mercury briefly made an appearance, right next to the Sun, and Mars was up most of the night. Even Uranus and Neptune were above the horizon, although not visible with the naked eye. And both of our contenders, Saturn and Jupiter, were visible in our night sky, although in different places.

Which one was it?

This planet, our planet which we tracked for hours, was Jupiter. I was wrong.

As I write this, 24 hours later, Jupiter will soon rise again, surrounded by his lovers, the Galilean moons, which I may yet see, or I may not.

I now know that what I perceived as rings were actually moons¹. The observation is the observation, but now I know the correct interpretation of the observation. That should not change what I actually see, just what I think it means.

1. My sources included Space.com, EarthSky, timeanddate and The Sky Live, and I gleaned some background from NASA.