and then… let things evolve

I watched the second episode of Cosmos: A Spacetime Odyssey tonight (hint: you can watch it online at Cosmos) and enjoyed it immensely. The story in this installment is about evolution, but for some reason, I was reminded of a line from the original Cosmos:  “If you want to make an apple pie from scratch, you must first invent the universe.” That line refers to all the cosmochemistry that went into making the ingredients of the apple pie. And Earth. And the tree that grew the apple. And you. And me.

The series will undoubtedly get around to talking about cosmochemistry, and I’ve written about it many times here and here and here. When chemical elements combine in just the right amounts and under the right conditions, somehow life arises. That is the way the story played out here on our planet, and there’s no doubt in my mind that it will (or has) happened elsewhere. Anyone who has studied chemistry, even for a short time, can figure out how chemical elements combine. Organic chemistry talks about the life implications of those combinations. Biology and biochemistry talk about the ways that life forms and evolves and exists as a result of chemical interactions. It’s something of a simplification to say that life is chemistry, but it if helps you understand how things are put together in the cosmos, then it’s a good step forward in learning about how they work.

In the second episode of Cosmos, Neil deGrasse Tyson walks us through the scientific facts of evolution using the domesticated dog as an excellent example of artificial selection of traits, and polar bears as a stunning example of natural selection for survival traits. As a servant to three cats, I kind of felt myself wondering how we humans have changed the evolution of our feline overlords, too, but I still applaud the series choice of showing just how dogs have made the transition in breeding and temperament from wolves to family friend. It’s actually a complex and beautiful way to show the unfolding of diversity in life, and once you grasp the basic precepts, it’s not hard to accept at all. In fact, it gets harder to posit supernatural effects in the face of just how much we DO know about evolutionary change in life forms. We’re human. We figure these things out. It makes no sense to deny that.

I find the process of evolution rather enthralling to learn about. I don’t know why some people have such a hard time understanding that THEY and all life on Earth are the product of evolution. Neil explores that idea of denialism in the show by simply stating that it’s human to want to differentiate ourselves from other life forms. We’re already differentiated — but, as he points out, we’re also united with ALL other life on the planet by our DNA and the chemicals that make up organic life as we know it. Our appearances, our intelligence, our daily lives — those are all based on how we evolved from that common twisted chain of life-directing molecules. That’s a fact, and no amount of denial is going to change the basic laws of physics and chemistry and how the complex processes of life evolve and endure. Rather than deny, why not use our beautifully evolved minds to learn about the cosmos and how it evolved? That’s a much better use of those hard-won brain cells than shutting them down to new possibilities, knowledge, and facts.

If nothing else, I hope that the new Cosmos will open minds that are closed (due to human frailty and fear) to learning and help their owners embrace and enjoy the cosmos for what it is.

A Celebration of Hubble’s 24th Year in Orbit

There’s nothing like a great picture of a nebula to stir up your imagination about distant stars and planets in space. Hubble Space Telescope has been taking images of big clouds of gas and dust ever since its first year in orbit, and those images remain some of the most popular and evocative space pictures. You find them all over the place — in books, planetarium shows, and once I even found some on the set of Star Trek: Voyager when I visited courtesy of writer Andre Bormanis.  Nebulae just say “space” to people. And, they’re cool to look at.

So, this month’s Hubble Favorite is the Monkey Head Nebula, which lies in the direction of the constellation Orion, which is home to vast clouds of gas and dust and star-forming regions. This nebula turns out to be a pretty busy place, cranking out stars like the bright ones you see here. In a previous entry, I talked about massive stars gobbling up the most star “stuff” as they formed, and that’s happening here, too. As these hot newborns evolve, they eat away at the clouds of gas and dust surrouding them, and that’s what gives starbirth nebulae their scalloped and sculpted appearance.

I’ve always been fascinated with the Orion Nebula. It seems to me to be the quintessential place to go learn about stars being born. In a few tens of millions of years, some of the most massive stars born in its clouds will start to die off in supernova explosions. When that happens, all their materials will get spread out to space, sowing the seeds for new stars, and maybe even some planets that happen to form around them. That’s one reason why starbirth nebulae are so interesting to study. Without them, we’d know much less about how our own Sun got its start some 5.5 billion years ago.