Cosmic Ice Laboratory Marla Moore Reggie Hudson Paul Cooper Zach Pozen

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Cosmic Ice Laboratory Marla Moore Reggie Hudson Paul Cooper Zach Pozen. Icy Astrobiological Environments. Solar System Surfaces. Comets. Interstellar. Interstellar Grains as Reaction Sites. Hydrogen Flow UV-Photolysis Lamp Flux 5 x 10 14 photon cm -2 s -1 Average energy 7.4 eV. - PowerPoint PPT Presentation

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Cosmic Ice Laboratory

Marla Moore

Reggie Hudson

Paul Cooper

Zach Pozen

Solar System Surfaces

Comets

Interstellar

Icy Astrobiological Environments

Interstellar Grains as Reaction Sites

Hydrogen Flow UV-Photolysis LampFlux 5 x 1014 photon cm-2 s-1

Average energy 7.4 eV

p+

IR Spectrometer

UV

Focus of Astrobiology Related Research

•Complex organic products from energetically processed nitriles

Infrared SpectroscopyChemical Analysis

•Oxygen/Ozone/Hydrogen Peroxide — Paul Cooper

•Student projectsCH4

C2H4O isomersOCS 

Nitrile-CH3CN

•Acetonitrile has been detected on Titan, in cometary comae and in the ISM.

•If bombarded by radiation---

•More complex molecules?

•Prebiotic molecules result—

e.g.Amino acids ?

C

C

N

H

H

H

(Hudson & Moore, Icarus, 2004)

HNC, CH2=C=NH, HCN (?)

OCN−, CH2=C=NH, HCN (?), CO2 (?)

CH3CN

p+

H2O p+

Nitriles Complex OrganicsInfrared Spectroscopy

ketenimine

Formation of Ketenimine and HCN

A structural isomer:

C C N

H

H

H

Energetic input gives rapid isomerization or cleavage of C-C bond?

Formation of OCN-

Polyatomic anion:-O C N

O C N-

Oxidation product of water and CH3CN

Intermediate in oxidation to CO2

Stabilized by resonance

Formation of Carbon Dioxide

•CO2 is an oxidation product of OCN-

?

Room temperature residues

Analysis of residue--Search for amino acid synthesis

.5

.55

.6

.65

.7

3500 3000 2500 2000 1500 1000 500

.5

.55

.6

.65

.7

3500 3000 2500 2000 1500 1000 500

Absorbance / Wavenumber (cm-1) Paged X-Zoom CURSOR

File # 1 : NEWSPCTR11 1/13/2005 1:31 PM Res= 4

288 K Irradiated CH3CN, Next Morning, Under Vacuum

MID IRSpectrum

Nitriles Amino AcidsChemical Analysis

p+

Sample

Aspartic Acid

Glycine

AlanineAlanine

ABAABA

n-propylamine

i- propylamine

Glycine

Work in Progress

• Finish analysis of residues, blanks, and analysis of higher temperature experiments.

•Publish results

•Search for cytosine

and other pyrimidinescyanate (OCN

-)

HC C CN

N

N

NH2

O

H

H

H

energy

H2O

Progress Report 2005

Talks and Posters:InvitedUMDNotre DameRPIIAU-AsilomarPacifiChem

 Publications and Proposals:

DPS- posterNAI-Boulder-2 postersAOGS-Singapore-co-organized 2 sesssions-2 talksNASA Laboratory Workshop-2 postersACS-Atlanta-talk, 2 student postersAbSciCon-talk, poster

Hudson and Moore2 published2 in pressco-authored 1 book chapterco authors on A&A benzene related paperHudson only, 1 in press 1 book chapter proposed and accepted (with astrobiology component)1 AGU session proposed and accepted (with astrobiology connection)

 

Facilities:

•New electron gun has arrived

•Money for new optical bench has been received

http://www.eckerd.edu/academics/chemistry/courses/ch210/

Education outreach:

Astrobiology courses taught

Mentored 3 students

Zach Pozen

2 studentsfrom the US Naval Academy

www-691.gsfc.nasa.gov/cosmic.ice.lab

Web page is up to date

Session 18---Tuesday 3:45

Ice Prebiotic Chemistry of Nitriles: Identification ofComplex Organic Products

Reggie Hudson

Uv and ion bombardmentMeV

Cosmic RayMagnetospheric

H+

On+, Sn+

Bombardment

Photolysis

UV Photons

Sputtering

Radiolysis