Monday, March 31, 2008

Reflected Light From an Exoplanet Seen


Credit: 2007, ETH Zurich, S.V. Berdyugina
Last December, a team of astronomers with the Zurich's Institute of Astronomy, imaged, for the first time, the reflected light of an exoplanet (known as HD9189733b) using polarization (similar to how Polaroid sunglasses work). Because of this, they were able to, again for the first time, directly determine the orbit of an exoplanet. The planet orbits the dwarf star HD189733 located more than 60 light years away in the constellation Vulpecula. It orbits very close to its parent, with a year measured in just a couple of days. Because this close proximity, HD9189733b's atmosphere is swollen by the heat, as well as brightly reflects the dwarf stars light - which makes it easier to be detected visually.

This is an exciting development; another step toward being able to eventually (though probably not that far away) determine the atmospheric composition of another planet.

It may be that we will first detect extraterrestrial life not by their radio signals, but by visually seeing and analyzing their planet's atmosphere!

Reference:

ETH Zurich/Swiss Federal Institute of Technology. "Exoplanet Reflected Light Detected For The First Time." ScienceDaily. 28 December 2007. 31 March 2008 <http://www.sciencedaily.com/releases/2007/12/071226225432.htm>.

Tuesday, March 18, 2008

Population Bottlenecks

This is something I will return to after some more research, but I find it very intriguing how population bottlenecks have affected the human race. A population bottleneck occurs when either a significant percentage of a population or species is reduced by 50% or moreor when a small group gets isolated from the main population (called the "founder effect"). This results in increased gene frequencies (genetic drift), as well as resulting in increased inbreeding. This has profound effects on the future of the species affected by the bottleneck.

These bottlenecks usually occur due to some large disaster, whether cosmic, natural, or man-made such as meteor impacts, super volcano eruptions, climate change, disease, or war, just to name a few.

So when thinking about alien realities, we need to keep in mind that unexpected evolutionary pathways can occur because of bottlenecks. Think of this hypothetical situation: a small group of a sentient species is exiled or chased away by a larger, stronger group (of the same species). Left alone, Darwinian forces here would predict that eventually the stronger group's genes would win out over the weaker group. But if a disaster comes along that wipes out the stronger group but, by the luck of the draw, the small, weaker group manages to survive - guess who will repopulate the species?

On Earth we have isolated groups where color-blindness is much higher than the average human population, or where six-fingers is the norm, or people who walk on all fours. If a major disaster were to happen and by fluke stroke of luck one of these isolated groups survived, the future of the human race would be greatly changed (where, for instance, those with five fingers would be the odd ones). Of course, some of these attributes are recessive, and eventually the dominant genes would reassert themselves as the norm.

Thursday, March 6, 2008

Music

Today I was listening to "Club Soda" by Ghostland Observatory off of their new album, Robotique Majestique. I like their instrumentals, the vocals - not so much. Just my personal tastes. But it got me to thinking about music and how some claim it to be "the universal language" (others would argue it is mathematics, but then there is a relationship between music and mathematics, but I digress...).

Back to "Club Soda:" the song has the sound of something rising, or powering up, or racing toward the listener. This sound, for Earthlings, adds a dramatic component. If reversed, it can remind one of the sound of something crashing, or a bomb falling. Whether caused by Doppler shift, or by the physics of sound in a chamber that is decreasing the volume of air, or by the physics of sound as a spinning mechanical device increases in speed, it gives the feeling of something approaching. This comes from our experiences in the world. When we fill up a bottle, when a train heads towards us, when a bomb or mortar flies toward us, or when a powerful motor spins up to speed, there is that sound sliding up the scale.

Would aliens feel the same? Physics is physics whether here or on Omicron Ceti 8, and sentient beings would most probably be good at finding patterns and making connections. However, for sentient beings that are deaf by nature and who mainly communicate through scent, touch, or light, this sliding scale sound may have no meaning to them whatsoever.

For those that do hear, the question may actually be do they experience emotion as we do, and attach emotion to sounds? They may not. Or may experience the emotions differently. Some will communicate by sound in different ways than we do because of their different physiology and/or the differences in physical environments (denser atmosphere or underwater, for example) - and the sliding scale sound may be one they reproduce naturally themselves in communicating and so does not have any dramatic connotation to them.

Hmm, but yet... it would seem that nature likes to be efficient when it can, or that it at least tries to be. It seems very logically, and efficient, for creatures to interpret the sound of something approaching, or falling, or increasing in power as something dramatic - to stop and pay attention to. Creatures that do are more likely to survive than those that do not.