[ExI] SETI reviews the Drake equation

[Stuart LaForge]

Quoting myself (again):


> Yet when we examine living organisms, whether they be humans or the 
> lowliest bacterium, their biomolecules are always just one of the 
> mirror images and not both. For example all glucose recovered from 
> living cells has left-handed chirality and all amino acids from cells 
> are right-handed.

Quick correction, I have these exactly reversed biologically-active  
glucose is right handed and biological amino acids are left-handed.

> And this is where Sgr A*, the 4 million solar-mass black hole at the 
> center of our galaxy comes into play: At some point in our galaxy's 
> evolution, two black holes collided in the center of our galaxy, in 
> such a way that by complete random chance the resultant super-massive 
> black hole (SMBH) Sgr A* was tilted on it's side like the planet 
> Uranus, precessing like a gyroscope with its radio-jet, which is 
> essentially a gigantic circularly-polarized broad-spectrum laser/maser 
> in just such a fashion to track our sun's orbit around the disk.

The math on this doesn't seem to be working out. Namely I don't know  
where the torque would come from to cause SgrA* to precess like that.  
So being in the path of the black hole's radio jet might just be a  
rare occurrence that happens twice every 230 million years when the  
sun's orbit crosses the radio jet's path and we just happened to be  
crossing the beam path when we looked at it.

That still would have given SgrA* plenty of opportunities to kick  
start abiogenenesis on earth, but make it a lot less of an existential  
threat going forward.

Stuart LaForge