Category Archives: exploration

aliens, exoplanets, exploration

Lighting up the Night

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Would Aliens Do That?

A nighttime view of Beijing's city lights splashing out to space. Earth's night-time side is aglow with light splashed carelessly to space. Image courtesy of the Image Science & Analysis Laboratory, NASA Johnson Space Center

We humans spend a lot of money turning our lights on at night.  We light up our houses, our parking lots, our highways, our high-rise buildings—you name it. If we build it, we light it up.  You don’t have to go to space to know that we have a love affair with illumination. That’s because light pollution is a constant on every continent. But, somehow, it seems more obvious when you see it from space.

Astronauts living and working on orbit since the dawn of the Space Age have shown us in countless images how Earth’s brightly lit cities glitter like diamonds on the night-time face of our planet. To any visitor from another planet coming to visit us, those lights have a simple message: here is a civilization that is so wealthy that it can spend money lighting up the night-time sky. Here are beings who want to advertise their presence to the cosmos.  Here is evidence of intelligent life!

Actually, our alien visitors wouldn’t have to be all that close to detect our light pollution and make some guesses about our civilization. If they had powerful enough telescopes, observers on distant planets could simply watch Earth as we turn our lights on at night. Our planet’s dark side could be detectable with a powerful enough telescope and the right kind of observational techniques.

Will alien civilizations splash their lights to space? If so, Harvard astronomers think we could use those lights to detect their existence. Credit: David A. Aguilar (CfA)

The idea is not so farfetched as it sounds. Two researchers representing Harvard University’s Center for Astrophysics and Princeton University have suggested that Earth-bound astronomers use that exact method to search for life on other planets beyond our solar system.  Those changes, if astronomers can spot them, could be due to artificial illumination, and that would signify the existence of intelligent life on distant worlds.  (You can read more about the research behind the idea here).

It’s an intriguing twist on the search for extraterrestrial civilizations, and with the pace of advancements in telescope technology, such research is not that far off in our future.  But, I have to wonder: would every civilization be so wasteful of its resources by lighting up the sky?  I suppose we’ll find that out when we spot those distant worlds and spy out their cities and roadways and parking lots and other places they choose to illuminate, just as we do here on Earth.

Want to see more images of Earth at night? Browse through the Earth from Space website. and you’ll see our planet in all its glory, as witnessed through the eyes and cameras of Earth-orbiting astronauts.

astrobiology, exoplanets, exploration, extrasolar planets, GJ 1214b, life, mono lake, NASA

Arsenic-Eating Life and New Planets

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Scientists Study Places Where Life Thrives…

and where it May Someday Exist

Judging by the uproar over the past few days in the blog-o-sphere and comment-o-sphere, you’d think that NASA was announcing that life had been discovered on Mars or Titan or any number of other unlikely places.  What I’ve seen in idle speculation and comments on blogs, FaceBook, and even on some news sites,  leads me to wonder if there’s any intelligent life left on the Web. I mean, come on.  There’s been some pretty irresponsible commentary by all kinds of people (including journalists, bloggers, and some scientists) and it’s really taking away from the wonderfulness of the actual discoveries.  Well, let’s take a look at the REAL stories and see what all the fuss is about.

Arsenic-processing bacteria like those growing in Mono Lake, California. Courtesy NASA.

The first, being talked about today, is the finding that some bacteria that live in Mono Lake in California appear to eat and apparently thrive on arsenic — a chemical that is usually toxic to life.  This finding is based on laboratory studies of these bacteria. In such a setting, not only can these buggers eat the stuff, but they appear to have evolved enough to be able to chemically alter it and incorporate it into their DNA. The lead researcher, Dr. Felisa Wolfe-Simon at the U.S. Geological Survey, put it pretty well: “”We know that some microbes can breathe arsenic, but what we’ve found is a microbe doing something new — building parts of itself out of arsenic,” she said. “If something here on Earth can do something so unexpected, what else can life do that we haven’t seen yet?”

Bugs eating arsenic?  That result is going to have a huge impact on other areas of research into life and its processes, including the study of Earth’s evolution, organic chemistry, biogeochemical cycles, disease mitigation and Earth system research.  To put it simply, this has implications for understanding the chemical environments that life can exist and thrive in.  Essentially, this NASA-funded research is changing our very basic knowledge about what kinds of life forms we have on this planet, and where they can exist and thrive.

Now, this is a far cry from breathless claims that NASA was going to announce life on Mars and all the other shouting that we’ve been seeing on the Web and in the press the past couple of days. Those are the usual claims, and I find them wearisome when they come without any proof or understanding of the actual science being reported.

On the other hand, this report is REAL science being shared by real scientists who have been out the field doing what science does best: examining, studying, and understanding what’s right in front of us. It’s exciting. It’s different. And, it’s going to spur other scientists to study the results and extend them into other areas.  But it’s not little green life forms holding up their middle fingers and saying, “Take me to your arsenic.” Quite the opposite: the little life forms seem to have found their arsenic and said, “We’re happy here, thank you very much.”

You can also read more about this fascinating biological discovery at Science’s web site, the journal that is publishing the story of the arsenic-loving critters.

Artist's conception of the super-Earth planet GJ 1214b. Courtesy ESO.

The second discovery this week that has implications for life is the revelation by astronomers using the Very Large Telescope in Chile of a super-Earth exoplanet (i.e. a semi-Earthlike planet bigger than Earth) that has what appears to be a water-rich atmosphere.   This water could be in the form of steam, or wet clouds or hazes.  GJ 1214b has a radius of about 2.6 times that of the Earth and is about 6.5 times as massive. Its host star is a small faint star about 40 light-years from Earth in the constellation of Ophiuchus. You can read more details here.

Of course, as soon as news of this discovery came out, I began to see speculation about life being discovered on that planet.  Not just in news sites, but all around the web-o-sphere and by commentators who should have known better.  I hate to be a wet blanket (so to speak), but the presence of water does NOT equal the presence of life. It DOES mean, however, that the environment on that planet could be conducive to the formation of life that depends on water.  And, that’s pretty darned cool.  Still, no actual discovery of life has happened there… yet.

I think that this tells us, more than ever, that the conditions for life do exist “out there” and that the formation of planets where life could form and exist is not limited to our own solar system.  It’s not surprising to find these planets — eventually we were bound to. Coupled with the astrobiology discovery announced today, it tells ME that this universe is complex, fascinating, and always ready to hand us a surprise or two!