Searches for interstellar molecules of potential prebiotic importance

Kuan, Y. J.; Charnley, Steven B.; Huang, Hui‐Chun; Kisiel, Zbigniew; Ehrenfreund, P.; Tseng, W. L.; Yan, C.

doi:10.1016/j.asr.2003.04.004

Cited by 65 publications

(59 citation statements)

References 34 publications

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“…The chemistry of the W51e2 region has been investigated by several groups. For example, Zhang et al (1998) has done CH 3 CN and CS (3-2) observations, Remijan et al (2004Remijan et al ( , 2002 investigated CH 3 CN and CH 3 COOH, Liu et al (2001) looked for HCOOH in this source and Kuan et al (2004) searched for several molecules of potential prebiotic importance. The hydrogen column density 3.6 × 10 23 cm −2 (Ikeda et al 2001) is based on C 18 O data from Schloerb et al (1987).…”

Section: Source Selectionmentioning

confidence: 99%

Trans-ethyl methyl ether in space

Fuchs

Fuchs²,

Giesen³

et al. 2005

A&A

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An extensive search for the complex molecule trans-ethyl methyl ether towards several hot core regions has been performed. Using the IRAM 30 m telescope and the SEST 15 m we looked at several frequencies where trans-ethyl methyl ether has strong transitions, as well as lines which are particularly sensitive to the physical conditions in which the molecule can be found. We included G34.26, NGC 6334(I), Orion KL, and W51e2 which have previously been proven to have a rich chemistry of complex molecules. Our observations cannot confirm the tentative Orion KL detection made by Charnley et al. (2001) within their stated column density limits, but we confirm the existence of the trans-ethyl methyl ether towards W51e2 with a column density of 2 × 10 14 cm −2 . The dimethyl ether/methanol ratio of 0.6 as well as the newly found ethyl methyl ether/ethanol ratio of 0.13 indicate relative high abundances of ethers toward W51e2. Furthermore, the observation of ethyl methyl ether also confirms the importance of ethanol as a grain mantle constituent. We present new upper limits of around 8 × 10 13 cm −2 for the column densities of the molecule toward Orion KL, G34.26, NGC 6334(I) and estimate the column density towards SgrB2(N) to be of the same order. The W51e2 observations are discussed in more detail.

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Section: Source Selectionmentioning

confidence: 99%

Trans-ethyl methyl ether in space

Fuchs

Fuchs²,

Giesen³

et al. 2005

A&A

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“…Of the molecular species identified so far in interstellar space, about 30% have isomeric counterparts ( Hollis 2005), including HCN/ HNC, CH 3 CN/CH 3 NC, CH 3 CH 2 OH/(CH 3 ) 2 O, etc., which have received much attention. Among the isomeric groups of polyatomic species, the isomeric family with molecular formula of C n H 2n O is of special interest, since these molecules may represent the astrochemical evolution of the interstellar medium and have potential prebiotic importance ( Turner & Apponi 2001;Charnley 2004;Kuan et al 2004). The members of this family include formaldehyde (Snyder et al 1969), acetaldehyde (Gottlieb 1973), acetone (Combes et al 1987), ethylene oxide (Dickens et al 1997), ethenol (Turner & Apponi 2001), and propanal (Hollis et al 2004).…”

Section: Introductionmentioning

confidence: 99%

Interstellar Enols Are Formed in Plasma Discharges of Alcohols

Wang

Zhang

et al. 2008

ApJ

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Laboratory low-pressure cold plasma discharges, which are used to simulate some hot core environments in the star-forming region, have been investigated by employing single-photon vacuum ultraviolet ( VUV) photoionization mass spectrometry. Enols with two to four carbon atoms were detected in plasma discharges of alcohols, indicating that enols can result from alcohol destruction induced by ultraviolet and cosmic radiation and accelerated electrons that are abundant in the interstellar medium. This observation, together with the detection of ethenol toward Sgr B2, suggests that larger enols, such as propenols and butenols, should be in the search list of potential molecular species to be identified in interstellar space. The laboratory experiment presented here shows that VUV photoionization sampling of plasma discharges is a valuable method for guiding the search for new interstellar molecules and helping to understand the transformation mechanism of molecular species of astrochemical significance.

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“…To date, none of these compounds have been detected (Simon and Simon 1973;Kuan et al 2003Kuan et al , 2004Charnley et al 2005;Brünken et al 2006). Nonetheless, PAHs are known to be ubiquitous in galactic and extragalactic interstellar/circumstellar environments, and polycyclic aromatic nitrogen heterocycles (PANHs) are expected to be present as well (Allamandola et al 1989;Puget and Léger 1989;Roelfsema et al 1996;Galliano et al 2008).…”

Section: Potential Environments For Prebioticmentioning

confidence: 99%

Photosynthesis and Photo-Stability of Nucleic Acids in Prebiotic Extraterrestrial Environments

Sandford

Bera

Lee

et al. 2014

Topics in Current Chemistry

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Laboratory experiments have shown that the UV photo-irradiation of low-temperature ices of astrophysical interest leads to the formation of organic molecules, including molecules important for biology such as amino acids, quinones, and amphiphiles. When pyrimidine is introduced in these ices, the products of irradiation include the nucleobases uracil, cytosine, and thymine, the informational sub-units of DNA and RNA, as well as some of their isomers. The formation of these compounds, which has been studied both experimentally and theoretically, requires a succession of additions of OH, NH 2 , and CH 3 groups to pyrimidine. Results show that H 2 O ice plays key roles in the formation of the nucleobases, as an oxidant, as a matrix in which reactions can take place, and as a catalyst that assists proton abstraction from intermiediate compounds. As H 2 O is also the most abundant icy component in most cold astrophysical environments, it probably plays the same roles in space for the formation of biologically relevant compounds. Results also show that although the formation of uracil and cytosine from pyrimidine in ices is fairly straightforward, the formation of thymine is not. This is mostly due to the fact that methylation is a limiting step for its formation, particularly in H 2 O-rich ices, where methylation must competes with oxidation. The relative inefficiency of the abiotic formation of thymine to that of uracil and cytosine, coupled with the fact that thymine has not been detected in meteorites are not inconsistent with the RNA world hypothesis. Indeed, a lack of abiotically produced thymine delivered to the early Earth may have forced the choice for an RNA world, in which only uracil and cytosine are needed, but not thymine.

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Searches for interstellar molecules of potential prebiotic importance

Cited by 65 publications

References 34 publications

Trans-ethyl methyl ether in space

Trans-ethyl methyl ether in space

Interstellar Enols Are Formed in Plasma Discharges of Alcohols

Photosynthesis and Photo-Stability of Nucleic Acids in Prebiotic Extraterrestrial Environments

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