Category Archives: life

The Seeds of Life

Cosmochemistry in Action

It’s pretty common knowledge in astronomy these days that planets grow from seeds hidden in clouds of gas and dust around other stars. Thats how our solar system got started a few billion years ago, and studying how it happens elsewhere helps us understand the birth of our own planet. But, the big question is always, “What about life?”

protoplanetary disk

The Spitzer Space Telescope has been peering into clouds of gas and dust enshrouding nearby stars, and discovering the seeds of life. What are those seeds? Organic molecules (in the form of gases) and water vapor, to name a couple.

Two scientists who use SST, John Carr of the Naval Research Laboratory, and Joan Najita of the National Optical Astronomy Observatory (in Tucson, Arizona), used Spitzer’s infrared spectrograph to measure and analyze the chemical elements in a protoplanetary disk around a young star called AA Tauri. It’s less than a million years old and is pretty typical of young stars that have the cosmochemical seeds of life scattered around them in dense, dusty disks.

Other scientists are using Spitzer to look for water molecules in these same types of disks. And, they’re finding them.

This is important work, folks. Water and organics are two of the big three things you need to form life. But, before we get carried away and start thinking of little green beings from AA Tauri, keep in mind that the planets have to form first. Then the life will come (if all the conditions are good for it). It’s a big deal right now to find these materials in places other than our own solar system. It means the conditions for planets like Earth to form are out there. And, the existence of organics and water tell us that some billions of years from now, life might exist on planets around these stars. Visit the Spitzer news announcements for more background on this new set of findings.

Alien Life, Distant Worlds, and Us

 

Worldly Thoughts

 

I woke up this morning thinking about the latest discoveries of planets around other stars. Astronomers are using a variety of techniques to find them, and totals are racking up quickly. Most of the planets that have been found are “Jupiter-like,” meaning they are gas giants with huge atmospheres. They’re relatively easy to find because of their size. Worlds like Earth (the terrestrial worlds) are smaller, and tougher to spot. But because astronomers have been able to spot the environments in which planets form around stars (that is,in clouds of gas and dust), it’s pretty likely that there are many terrestrial planets out there, too. We just have to dig into those clouds and come up with the planets. Which will take time and some sophisticated astronomy search methods.

Yesterday, the Spitzer Space Telescope folks released news that Earth-like planets might form around many of the closest Sun-like stars. This orbiting telescope, which is sensitive to infrared light (think “warmth”) was used to study dust envelopes around nearby stars. These are warm places. Dust closer to the star is hotter than dust farther away from the star, the warm dust is a fair indicator of the types of materials that form rocky planets—that is, Earth-like worlds. Such discoveries always lead to the old question, “Is there life out there?” It’s a fair one to ask.

For now, the definitive answer is “No.” But, that’s because we haven’t seen the evidence for any other life out there. Yet. We don’t have communications from that life, or pictures of it, or any other manifestations of it that we recognize as a definite “signal.” But, if it’s out there, there’s some chance that we’ll detect it. Some day.So, what I woke up thinking about was what life on OUR planet will be like once we discover life somewhere else. Will it change us in some non-physical way? Will our thinking change about life? About politics? Religion? Education? Science? The way we treat our own planet?

Life from “Out There”—Threat or Learning Experience?

Courtesy SwapmeetDave.

The concept of life elsewhere is a major staple of science fiction stories. Depending on the story being told, the life from “out there” can be threatening, friendly, super-intelligent, simple, primitive, or depicted as being far beyond what we can comprehend. In reality, the life we find beyond Earth will likely be some combination of these factors, and perhaps look nothing at all like what we expect. How that life will act? Well… like we do with our deities, humans have painted aliens with a palette of characteristics that we most admire and/or fear in ourselves. When we DO get to meet other forms of life, the experience may teach us a bit more about respecting the life forms we share Earth with.Wonder about why I say that?Well, consider for a moment what humans and human activity (such as whaling) looks like to the cetaceans that inhabit our planet. Or, think about what our planet might look like to alien visitors who come in search of us and they find how we’ve treated our environment.These may be extreme examples, but the point I’m trying to make here is that the search for intelligent life (and other planets) isn’t one-sided. If there’s somebody out there looking for life elsewhere, and they find US, will we inhabit their worst nightmare or exemplify their fondest wishes? Either way, the possibilities are thought-provoking.