Hydrogen radio emission

The radio emissions from Uranus arise from sufficient depths that collision-induced absorption by hydrogen is an important source of opacity at millimeter wavelengths. Ammonia is severely depleted in Uranus atmosphere, at least at pressure levels less than 25 bar. Since, based upon planet formation theories, nitrogen must be present in at least solar proportions, it is believed that ammonia gas is abundant at deeper levels, but reacts with H2S to form a cloud of NH4SH. If indeed this process accounts for the observed depletion in NH3, hydrogen sulfide should be enriched in Uranus atmosphere by about an order of magnitude over solar S. Such an abundance of H2S itself will contribute to the radio opacity in Uranus atmosphere and actually help reconcile observed spectra with models. 

The existence of molecular species in interstellar space has been known for almost seventy years. The first observations involved the electronic spectra, seen in absorption in the near-ultraviolet, of the CN, CH [28] and CH+ [29] species. Radiofrequency lines due to hydrogen atoms in emission [30] and absorption [31], and from the recombination of H+ ions with electrons were also known. However, molecular radio astronomy started with the observation of the OH radical by Weinreb, Barrett, Meeks and Henry [32] in 1963 in due course, this was followed by the discovery of CO [33]. In the subsequent years over 110 molecules have been observed in a variety of astronomical sources, including some in galaxies other than our own. Nearly a third of these are diatomic molecules, with both closed and open shell electronic ground states, and some were observed by astronomers prior to being detected in the laboratory. 

The astrophysical version could be used for high school physics and astronomy classes for search and discover activities, in a simplified form. For elementary school, the concept of space chemistry can be illustrated by the many different types of species observed, such as N2H, CCH, HC5N. Atomic emission from hydrogen Ha lines also observed at radio telescopes can be used to exemplify the Bohr atom. 

We obtained a polarization image at K (2.18 on) of BN/EL region in an area of 16.6 X 4.6 arc minuets, and found extended 4.6 X 4.6 ar-cmin) polarized nebulosity (Fig. 2). Polarization vectors of the nebula show centro-symmetric pattern centered near BN/KL, suggesting it is a reflection nebula. It has clear relations with the distribution of the 1 - 0 S(l) molec-ular hydrogen emission as well as radio molecular line emission such as CS and HC3N, giving us the information about the mass distribution around BN/KL cluster. 

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