This thesis investigates photonic spectroscopy and its use in astronomy. In chapter two the theory associated with both astronomical spectroscopy and photonic spectroscopy is shown. The convergence of the two in the field of astrophotonics is discussed along with existing work in the field. In chapter three models of the Integrated Photonic Spectrograph are created and compared like-for-like with existing instruments. The results suggest that the Integrated Photonic Spectrograph will be similar to existing instruments in terms of size and will require more detector pixels for a full instrument. In chapter four the modelling is extended, examining the areas where pho- tonic spectroscopy could show advatanges over conventional instrumentation. This is done by varying spectral resolution, telescope diameter, seeing and num- ber of objects sampled. The results show that the Integrated Photonic Spec- trograph will perform best when the telescope is close to the diffraction-limit, both in terms of size and number of detector pixels required. Science cases are presented for these areas. In chapter five different concepts for a redesigned Integrated Photonic Spec- trograph are presented and the advantages and disadvatanges of the variations are commented upon. The two that are chosen for development require the telescope Point Spread Function to be reformatted to a long slit. This device, which we have named the photonic-dicer is presented in chapter six. Its design, manufacture and testing is discussed both in the laboratory and on sky in conjunction with the CANARY adaptive optics system. Finally chapter seven presents our concluding remarks and discussions for future work.

This thesis aims to elucidate the changing forms of engagement between Europeans and Indians in relation to astronomy in India between 1784 and 1876. It seeks to trace the evolving contexts in which knowledge of astronomy was developed and to provide a nuanced characterisation of the resultant cognitive interface between Europeans and Indians, focusing in particular on Bengal and Bombay. The defining features of this period saw Europeans exploring the history of Indian astronomy, before establishing observatories and colleges to foster modern Western astronomy, while Indians turned to rethink how the history of Indian astronomy (and astrology) fitted with modern science. Yet while recent historiographical interventions have drawn attention to the more philosophical forms of engagement, this thesis contends that such a concentration has elided a much more practical engagement between Europeans and Indians in relation to modern (Western) astronomy in India. This engagement was not about a constant process of Indians rationalising participation in modern science, or looking backwards while moving forwards. In addition, it was premised more on collaborative and experiential constructions of knowledge, without express awareness of fixed "Western" or "Indian" paradigms. There was evidence of such engagement in the observatory and in the field, as well as in certain college settings, and in some parts of India more than others. However, racialised colonial institutions and attenuated educational schemas could at length hinder such possibilities, leaving the spotlight on the more philosophical forms of engagement. This thesis hence aims to address a lacuna in the history of science in colonial India by reappraising the significance of astronomy during these years. Through drawing on a range of written texts and physical objects in relation to astronomy, as well as on inter-disciplinary perspectives, it seeks to reflect the heterogeneous nature of the Indian intellectual climate in the colonial period.

International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / The National Radio Astronomy Observatory (NRAO) operates the Very Large Array (VLA) Radio Observatory in New Mexico, and the Very Long Baseline Array (VLBA) with 10 radio antenna in locations from Hawaii to St. Croix, as well as other radio telescopes at Green Bank, West Virginia, and the 12 meter radio antenna near Tucson, AZ. Although radio frequency (RF) bands have been set aside for passive use by these radio telescopes, harmful interference from increased demands on the radio spectrum is a growing problem for earth-based radio astronomy. For example, locating a radio observatory in a remote area is little defense from satellite downlink telemetry. This paper describes why the operation of the radio telescopes is susceptible to RF telemetry interference, what bands are particularly vulnerable and at what power levels, and how data collection and centralized control of the arrays are accomplished without RF telemetry.

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