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We present Hyperion, a mission concept recently proposed to the December 2021 NASA Medium Explorer announcement of opportunity. Hyperion explores the formation and destruction of molecular clouds and planet-forming disks in nearby star-forming regions of the Milky Way. It does this using long-slit high-resolution spectroscopy of emission from fluorescing molecular hydrogen, which is a powerful far-ultraviolet (FUV) diagnostic. Molecular hydrogen (H-2) is the most abundant molecule in the universe and a key ingredient for star and planet formation but is typically not observed directly because its symmetric atomic structure and lack of a dipole moment mean there are no spectral lines at visible wavelengths and few in the infrared. Hyperion uses molecular hydrogen's wealth of FUV emission lines to achieve three science objectives: (1) determining how star formation is related to molecular hydrogen formation and destruction at the boundaries of molecular clouds, (2) determining how quickly and by what process massive star feedback disperses molecular clouds, and (3) determining the mechanism driving the evolution of planet-forming disks around young solar-analog stars. Hyperion conducts this science using a straightforward, highly efficient, single-channel instrument design. Hyperion's instrument consists of a 48-cm primary mirror with an f/5 focal ratio. The spectrometer has two modes, both covering 138.5-to 161.5-nm bandpasses. A low resolution mode has a spectral resolution of R >= 10,000 with a slit length of 65 arcmin, whereas the high-resolution mode has a spectral resolution of R >= 50,000 over a slit length of 5 armin. Hyperion occupies a 2-week-long high-earth lunar resonance TESS-like orbit and conducts 2 weeks of planned observations per orbit, with time for downlinks and calibrations. Hyperion was reviewed as category I, which is the highest rating possible but was not selected.

Astronomical adaptive optics (AO) systems and wavefront sensors (WFS) have advanced significantly over the past three decades. However, WFS development has typically focused on coherent or incoherent sources. This work seeks to extend the design and optimization of astronomical WFS to partially spatially coherent sources, such as laser beacons with AO correction, to reduce the beacon size below the limit imposed by atmospheric turbulence. This work develops a theoretical foundation for partially coherent wavefront sensing using Hopkins' formula, leading to a discrete approximation of the Fisher information matrix for a generic class of astronomical WFSs. The derivation provides insight into the degradation in WFS sensitivity due to partial coherence and suggests an approach for mitigating the deleterious effects by limiting interference to include only coherent point pairs in the pupil. The derived numerical approximation also leads to a new technique for simulating partially coherence sources and linear WFSs using the coherent impulse response (CIR) of the WFS and the complex coherence factor of the source, evaluated at the entrance pupil. Because this new simulation approach more directly accounts for the effects of spatial coherence on the detector output, arbitrarily large source sizes can be quickly and accurately modeled. Insights gained by the theoretical work suggest two novel methods for optimizing WFS sensitivity with partially coherent sources: pupil segmentation (PS) and impulse response engineering (IRE). The former method takes the form of a hybrid WFS which pairs pupil subdivision with a high-sensitivity coherent wavefront sensing method to measure the wavefront over each subaperture. The latter method modifies the CIR of the WFS to match the coherence area of the source. Simulation results, using both the new CIR and more traditional Fresnel propagation methods, indicate a significant decrease in the photon-noise gain with each approach. The efficacy

Chemistry along the star- and planet-formation sequence regulates how prebiotic building blocks-carriers of the elements CHNOPS-are incorporated into nascent planetesimals and planets. Spectral line observations across the electromagnetic spectrum are needed to fully characterize interstellar CHNOPS chemistry, yet to date there are only limited astrochemical constraints at THz frequencies. Here, we highlight advances to the study of CHNOPS astrochemistry that will be possible with the Orbiting Astronomical Satellite for Investigating Stellar Systems (OASIS). OASIS is a NASA mission concept for a space-based observatory that will utilize an inflatable 14-m reflector along with a heterodyne receiver system to observe at THz frequencies with unprecedented sensitivity and angular resolution. As part of a survey of H2O and HD toward similar to 100 protostellar and protoplanetary disk systems, OASIS will also obtain statistical constraints on the emission of complex organics from protostellar hot corinos and envelopes as well as light hydrides including NH3 and H2S toward protoplanetary disks. Line surveys of high-mass hot cores, protostellar outflow shocks, and prestellar cores will also leverage the unique capabilities of OASIS to probe high-excitation organics and small hydrides, as is needed to fully understand the chemistry of these objects.

For centuries telescopes have been used to achieve an understanding of the universe and our place among it. As astronomical goals continue to push into infinite space for knowledge of the unknown, the instruments and mechanics must adapt to image farther and dimmer objects than ever before. To collect this information modern telescopes must grapple with the fundamental limitation imposed by the atmosphere. While more costly projects have begun to explore the option of launching smaller telescopes into space, the requirements for ground-based telescopes motivate an exponential increase in size and complexity. Larger apertures increase the sensitivity of detection, but the full resolution capabilities cannot be exploited without correcting the large and unpredictable aberrations imposed by the atmosphere. Adaptive optics seek to minimize these effects by applying an equal and opposite shape of the wavefront for correction. Wavefront sensors image incoming light such that phase aberrations are visible in the intensity field. The technique of this varies widely with application, but all wavefront sensors strive for high sensitivity, linearity, and accuracy over a large dynamic range. The proposed hybrid wavefront sensor builds from the well-established designs of the Shack-Hartmann and pyramid wavefront sensor, combining the ideal properties of both. Extensive simulations show that measurements from the hybrid wavefront sensor match the sensitivity of a pyramid wavefront sensor and the dynamic range of a Shack-Hartmann wavefront sensor. Two reconstruction methods estimate separate wavefront shapes corresponding to a highly sensitive or robust mode. These results provide a full understanding of the effect photon noise and initial aberration strength have on the hybrid wavefront sensor response. An adaptive optics testbench evaluates the hybrid wavefront sensor prototype, built primarily with commercially available optics. Single mode estimation tests show the linear resp

The first detection of radio waves from an astronomical object was in 1933 by Karl Jansky, when he reported radiation coming from the Milky Way at the Bell Telephone Laboratories. Very important discoveries have been observed using radio telescopes; from the microwave background radiation, one of the most important pieces of evidence for the Big Bang theory, to the latest image of a black hole captured by an international network of radio telescopes called the Event Horizon Telescope. Since astronomical radio sources (i.e. stars, nebulas and galaxies) are very far away, the radio waves that comes from them are very weak, requiring radio telescopes to have large reflective areas to collect enough radio energy to study them. Radio telescopes have typically large parabolic dish antennas, segmented in panels with different surface shape quality requirements proportional to the frequency of the radio signal observed. Different manufacturing methods have been used for microwave antennas. From flat panels made from a metallic mesh forming a gigantic spherical dish like the Arecibo Observarory, to the high precision electroformed panels done for the ALMA submillimetric telescopes. This doctoral dissertation project explores the electromagnetic radiation in the first chapter review, explaining the nature of light and particularly radio waves. It also review the radio telescopes optics, their main components and give some examples, including the ones visited by the author around the USA and Europe. Finally, the author explore different manufacturing methods commonly used in the production of radio reflector panels. On the second chapter, a method derived from Dr. Roger Angel glass slumping technology is explored to manufacture thermoformed reflector panels. The method, consisting of heating up a flat metallic sheet to reduce its yield strength and placing it into an adjustable mold to shape it into the required curvature. The third chapter propose a different method called El

Over two decades ago, the first planet around a star other than the Sun was discovered. With each passing year, more and more such exoplanets are discovered as new technologies and methods of discovery are developed and enhanced. As these techniques continue to mature, humanity gets closer to finally being able to answer the question: are we alone in the universe? Improvements to Adaptive Optics (AO) have enabled ground-based observation to expand to including high-contrast imaging instruments called coronagraphs that are meant to make the direct imaging of exoplanet light possible.Direct imaging is a method of observation that gives astronomers the ability to determine if a planet exhibits signatures of life via spectroscopic analysis for biomarkers. This is a difficult task for three major reasons: the planet orbits very close to its host star if it is located in the so-called habitable zone, the planet light is up to 10^-10 times fainter than the host star light, and static and quasi-static aberration being present during the observation degrades both coronagraph performance and post-processing technique efficacy. In this dissertation, I explore two methods for estimating non-common path aberration (NCPA) in the science instrument of AO enabled, ground-based telescopes. The first is a method called the Differential Optical Transfer Function (dOTF), which is a simple, non-iterative, non-interferometric technique to estimate the complex amplitude field in the exit pupil of an optical system exploiting the properties of the functional derivative of the Optical Transfer Function. dOTF is demonstrated in both simulation and lab based experiments, showing several possible applications, including AO system self calibration, segment cophasing, and estimating systematic NCPA using an off-axis light source. The second method is known as Frazin's algorithm, which is a statistical regression framework that uses wavefront sensor (WFS) and science camera (SC) telemetry with ad