Thursday, September 15, 2016

Rosetta's mass specs have confirmed complex organic molecules on Comet67P

You've probably already heard this, but if not -- its totally cool. According to this paper in Nature this week, Comet67P is just flying along leaving its long comet trail -- and that trail has a bunch of complex organic molecules in it!

My first question -- how do you confirm that? I'm first thinking the orbiter is probably doing this by spectroscopy and I'm gonna find those readings -- dubious -- but it turns out there are 2 mass specs on the Orbiter!

COSIMA is a Time Of Flight instrument designed by researchers at Max Planck that is capable of 1500 resolution at 100(m/z) but has an effective mass range up to 1,000 m/z. COSIMA's job is to collect dust particles and to analyze those particles by Secondary Ion Mass Spectrometry (SIMS). The surface of the particles are hit with an ion beam that ionizes stuff off the particles and in.

ROSINA is another mass spectrometer that is detecting and ionizing gases. I'm having trouble finding much in the way of details on it, but it I've ran across several descriptions of it as a double focusing mass spectrometer, something I'm not familiar with (and I've got to be at work super early today). The design should be investigated, though. It is capable of 3,000 resolution at 1% peak height. Which...honestly is a lot of resolution.

If I think of resolution at 1/2 height like this image I stole from the Fiehn lab...

We're calculating resolution at FWHM or 50% peak height. Unless I've got my numerator and denominator mixed up, if you're pulling 3,000 resolution at 1% peak height, that...ain't bad at all!

And I think I do have it right, because this double focusing mass spec is supposed to be able to tell CO from N2 -- (27.9949 from 28.0062!  that's 11 millimass units!!)

Okay. So...if there is evidence from these two impressive mass specs that survived a 4 BILLION mile trip there, I'm going to believe it!

But that isn't all! This isn't he first time we've shot instruments through the trails of comets. This is just the first time we've gotten readings this good. If you take the mass spectra from the other instruments in the past (as they show in the paper) you'll see that we have seen this in the trails of other comets.

So....there are huge balls of rock that fly through the universe shooting organic molecules the whole way....does anyone else feel like this alters an adjustment factor in the Drake equation at all?!?

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