Posts Tagged ‘Gliese 581’


If you know me, then you know that I am always on the lookout. For what? Science, of course, and art. Interesting and beautiful things. The internet is a better resource for novelty than anything else, but watchful and patient people sometimes get lucky. This was not an especially lucky week, but I did come across something that fulfilled my search criteria on technicalities. It’s pretty and it got me thinking – if my thoughts about it aren’t particularly favorable, they are at least energetic.

Don’t get me wrong, the video embedded below is essentially a modeling reel. It serves its purpose, which is to show-off some animation students’ acquired skills, and it’s quite good in that context. I have no desire to criticize their proficiency in the medium, but the obvious inspiration for the piece is a hot topic on this blog, so of course I took a closer look at it than I might have otherwise, and of course I brought it here to share.

Watch ‘Gliese 851′ then read on to see if it got you thinking along the same lines as me:

The first thing I noticed was the title. Now, there are a lot of stars named Gliese-something-something, but one has been in the news quite a bit more often than the rest; Gliese 581. Specifically because of that star’s unconfirmed ‘goldilocks’ planet. I assume the filmmaker was more interested in capitalizing on the name than on exploring any of the science associated with locating exoplanets or seriously speculating about extraterrestrial life. A couple of clues in plain sight verify my suspicion: For one thing, there is no star named Gliese 851, but that name is a common typo in articles about Gliese 581. For another, there appeared to be only two lifeforms on the wasteland planet depicted in the animation; one large human and one large tentacle-monster. Probably, the writer struck a compromise between savviness and laziness. The concept perfectly satisfies mainstream (i.e. low) expectations of science fiction, and it is about as deep as the average attention span for scientific content in the media.

But even assuming that the filmmakers invented a new star system on purpose, I have some questions about the setting. It looks like an industrial wasteland or a vast crash site. Or I suppose it could be an abandoned colony. Even still, why is the only human survivor wandering around in the open? With skin exposed? The atmosphere and daylight must be very earthlike, indeed. And if so, then what killed or repelled the other humans? Tentacle-monsters? But if so, then what did they eat/kill before humans arrived? I ask because I saw no evidence of other life on the planet, and it seems impossible that a species as complex as that alien could have evolved in the absence of biodiversity. Maybe it was the last of its kind. I mean, that’s possible given humanity’s propensity for environmental disaster.

What are your observations and speculations?

Goldilocks Is Nothing (But Noise)

Remember Gliese 581g? That recently discovered planet that had some scientists, and other hopeful stargazers, claiming certain knowledge that we are not alone in the universe? Well, Athena Andreadis gave us a gentle reality check last week, and this week we’ve been given a swift kick with the reality boot. The ‘Goldilocks Planet’ isn’t just unlikely to sustain life as we know it, the planet itself may not even exist except as ‘noise’ in its discoverers’ data.

So we should remain skeptical about claims that we’ve detected a signal from somewhere in the vicinity of Gliese 581g. But even if ET isn’t phoning our home, it’s still fun and wise to question our own significance in the universe.

Once Again with Feeling: The Planets of Gliese 581

Gliese 581 may be small as stars go, but it looms huge in the vision field of planetfinders.  As of late last week, measurements indicate the system has six planets of which three are Earth-size and -type, within the star’s habitable zone, with stable, near-circular orbits.

The Gliese 581 system has a persistent will-o-the-wisp quality.  Almost each of its planets (c, d, e and now g) has been pronounced in turn to pass the Goldilocks test, only to have expectations shrink when the data get analyzed further.  The first frisson of excitement arose when 581c was determined to be Earth-type, which quickened the usual speculations: atmosphere? water? life?  We don’t know yet and our current instruments cannot detect biosignatures at that distance (short of an unencrypted request for more Chuck Berry).  But there are some things we do know.

Gliese 581 is a red dwarf, a BY Draconis variable.  This makes it long-lived; on the minus side, it may produce flares and is known to emit X-rays.  Planets in its habitable zone are so close to it that they are tidally locked, always presenting the same face to their star.  The temperature differentials resulting from the lock imply hurricane-force winds and tsunami-like tides.  Gliese 581g, like 581c, is large enough to retain an atmosphere; the hope is that, unlike 581c or Venus, its specific circumstances have not resulted in a runaway greenhouse effect.

The real paradigm shift is the discovery that this solar system has many earth-size rocky planets, in contrast to the hot-Jupiter/hot-Neptune preponderance in most others.  The second enticing attribute of Gliese 581 is its relative closeness — a distance of merely 20 light years.  It is still millennia away by our present propulsion systems.  But I nurse the dream that if we see anything remotely resembling a biosignature, we will strive to reach it.  In the meantime, I suggest we give it a name that fires the imagination.  Perhaps Yemanjá, the Yoruba great orisha of the waters, in the hope that the sympathetic magic of the name will work.  Perhaps Kokopelli, the trickster piper of the American Southwest cultures, who may entice us thither.  I will conclude with the final words of my first article on Gliese 581:

“Whether Gliese 581c [g] is so hospitable that we could live there or so hostile that we could only visit it vicariously through robotic orbiters and rovers, if it harbors life — even bacterial life, often mistakenly labeled “simple” — the impact of such a discovery will exceed that of most other discoveries combined. Unless supremely advanced Kardashev III level aliens seeded the galaxy like the Hainish in Ursula Le Guin’s Ekumen, this life will be an independent genesis, enabling biologists to define which requirements for life are universal and which are parochial.

At this point, we cannot determine if Gliese 581c [g] has an atmosphere, let alone life. If it has non-technological life, without a doubt it will be so different that we may not recognize it. Nor is it a given, despite our fond dreaming in science fiction, that we will be able to communicate with it if it is sentient. In practical terms, a second life sample may exist much closer to home — on Mars, Europa, Titan or Enceladus. But those who are enthusiastic about this discovery articulate something beyond its potential seismic impact on biology and culture: the desire of humanity for companions among the sea of stars, a potent myth and an equally potent engine for exploration.”

Images: Top, comparison of the Sun and Gliese 581 habitable zones (the diagram is by Franck Selsis, Univ. of Bordeaux; the image of 581g was originally created for 581c by Ginny Keller); bottom, Kokopelli playing his flute.