A seal and a ferry in the Strait

The seal was swimming in the middle of the Strait of Georgia, the body of water that lies between Vancouver Island and the mainland. The Strait is about 25-30 kilometers wide, and the seal was right in the middle of the channel, a long way from land. It simply popped it's head above water and watched as the large ferry headed directly towards it. I was on the deck of the ship looking down. Just as it seemed we would bear down on it, the seal effortlessly ducked under the surface of the water and swam a few meters off to the side and then popped it's head out again, whiskers dripping wet, and looked up at the deck as the ferry sped past.

This happened also with a different seal in another part of the same crossing we were making between Nanaimo and Horseshoe Bay on the mainland.

While many people on the West Coast are used to these types of encounters with nature, this is still marvellously new to me. It's a thrill to find other forms of life coexisting with humans. It always serves as a reminder that we humans are but one player on this stage, only one aspect of a complex ecosystem.

Standing there on the deck of this gigantic steel machine, an intruder in the ocean world, we had a connection, that seal and I, that lasted just a few seconds. We looked at each other; but it was a moment that linked us as living beings - partners - on this planet we both call home.

To an observer in space, does our planet even exist?

If intelligent life is out there, way out there, would Earth even be visible? The strange answer is "no," but not because we are small or hard to see; but rather because to an observer far away our planet may not exist - yet.

Yes, indeed, another mind-challenging concept from the world of science.

An astrophysicist held an interesting discussion on Canadian radio earlier this year. The topic was the expanding universe, the speed of light and relative distances.

The scientist reminded listeners that when we see light from the stars, we're actually looking back in time. When we look at our nearest star, our sun, we're not seeing how the sun looks now, but how it looked a full eight minutes ago. That's how long it takes light to travel the distance from the sun to the earth.

The really interesting concept relates to other solar systems and galaxies. If we turn the thought around and place ourselves in the role of an observer from far away looking at the earth, then that observer would also be seeing OUR past.

They say the Milky Way, our home galaxy, is about 100,000 light years across. If someone's out there watching us from the other end of our own galaxy, they may be seeing Earth not as it is now, but only as it was when our species, Homo Sapiens, was just distinguishing itself from our "cousins," the Neandertals. No cities, no technology.

And that's just our own galaxy. The universe has millions of galaxies. Any observer watching from any of the other galaxies in our universe would see Earth much earlier in it's history.

So all the observations in space are true only as measurements of the past. Since the size of space is so enormous, even at the relatively fast speed of light, at 300,000 kilometers per second (186,000 miles per second), it takes a relatively long time for light to travel across these vast distances.

Finally, then, if intelligent life were searching for us from 5 billion light years away, they would not see us at all ! To them, we still don't exist. That's because Earth is calculated to be about 4.5 billion years old.

5 billion years ago, our solar system probably was just a loose collection of gases.

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Photo: wpclipart.com

For more thoughts on our universe, see posts in August (Are parallel universes real?)