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Comparison of their chemical compositions shows, to first order, a good agreement between the cometary and interstellar abundances. However, a complex O-bearing organic molecule, ethylene glycol (CH$_{2}$OH)$_{2}$, seems to depart from this correlation because it was not easily detected in the interstellar medium although it proved to be rather abundant with respect to other O-bearing species in comet Hale-Bopp. Ethylene glycol thus appears, together with the related molecules glycolaldehyde CH$_{2}$OHCHO and ethanol CH$_{3}$CH$_{2}$OH, as a key species in the comparison of interstellar and cometary ices as well as in any discussion on the formation of cometary matter. We focus here on the analysis of ethylene glycol in the nearest and best studied hot core-like region, Orion-KL. We use ALMA interferometric data because high spatial resolution observations allow us to reduce the line confusion problem with respect to single-dish observations since different molecules are expected to exhibit different spatial distributions. Furthermore, a large spectral bandwidth is needed because many individual transitions are required to securely detect large organic molecules. Confusion and continuum subtraction are major issues and have been handled with care. We have detected the aGg conformer of ethylene glycol in Orion-KL. The emission is compact and peaks towards the Hot Core close to the main continuum peak, about 2 to the south-west; this distribution is notably different from other O-bearing species. Assuming optically thin lines and local thermodynamic equilibrium, we derive a rotational temperature of 145 K and a column density of 4.6 10$^{15}$ cm$^{-2}$. The limit on the column density of the gGg conformer is five times lower.
We present sensitive high angular resolution submillimeter and millimeter observations of torsionally/vibrationally highly excited lines of the CH$_3$OH, HC$_3$N, SO$_2$, and CH$_3$CN molecules and of the continuum emission at 870 and 1300 $mu$m from
We present the first detection of interstellar acetone [(CH3)2CO] toward the high mass star forming region Orion-KL and the first detection of vibrationally excited (CH3)2CO in the ISM. Using the BIMA Array, 28 emission features that can be assigned
We present sensitive high angular resolution ($sim$ 0.1$$ -- 0.3$$) continuum ALMA (The Atacama Large Millimeter/Submillimeter Array) observations of the archetypal hot core located in Orion-KL. The observations were made in five different spectral b
We report the first detection and high angular resolution (1.8 $times$ 1.1) imaging of acetic acid (CH$_3$COOH) and gGg$^{prime}$--ethylene glycol (gGg$^{prime}$(CH$_2$OH)$_2$) towards the Orion Kleinmann--Low nebula. The observations were carried ou
Deuterated molecules have been detected and studied toward Orion BN/KL in the past decades, mostly with single-dish telescopes. However, high angular resolution data are critical not only for interpreting the spatial distribution of the deuteration r