The Origins Space Telescope will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. How did galaxies evolve from the earliest galactic systems to those found in the universe today? How do habitable planets form? How common are life-bearing worlds? To answer these alluring questions, Origins will operate at mid- and far-infrared wavelengths and offer powerful spectroscopic instruments and sensitivity three orders of magnitude better than that of Herschel, the largest telescope flown in space to date. After a 3 ½ year study, the Origins Science and Technology Definition Team will recommend to the Decadal Survey a concept for Origins with a 5.9-m diameter telescope cryocooled to 4.5 K and equipped with three scientific instruments. A mid-infrared instrument (MISC-T) will measure the spectra of transiting exoplanets in the 2.8 – 20 μm wavelength range and offer unprecedented sensitivity, enabling definitive biosignature detections. The Far-IR Imager Polarimeter (FIP) will be able to survey thousands of square degrees with broadband imaging at 50 and 250 μm. The Origins Survey Spectrometer (OSS) will cover wavelengths from 25 – 588 μm, make wide-area and deep spectroscopic surveys with spectral resolving power R ~ 300, and pointed observations at R ~ 40,000 and 300,000 with selectable instrument modes. Origins was designed to minimize complexity. The telescope has a Spitzer-like architecture and requires very few deployments after launch. The cryo-thermal system design leverages JWST technology and experience. A combination of current-state-of-the-art cryocoolers and next-generation detector technology will enable Origins’ natural backgroundlimited sensitivity.
The Origins Space Telescope (OST) is a NASA study for a large satellite mission to be submitted to the 2020 Decadal Review. The proposed satellite has a fleet of instruments including the HEterodyne Receivers for OST (HERO). HERO is designed around the quest to follow the trail of water from the ISM to disks around protostars and planets. HERO will perform high-spectral resolution measurements with 2x9 pixel focal plane arrays at any frequency between 468GHz to 2,700GHz (617 to 111 μm). HERO builds on the successful Herschel/HIFI heritage, as well as recent technological innovations, allowing it to surpass any prior heterodyne instrument in terms of sensitivity and spectral coverage.
The Origins Space Telescope (OST) mission concept study is the subject of one of the four science and technology definition studies supported by NASA Headquarters to prepare for the 2020 Astronomy and Astrophysics Decadal Survey. OST will survey the most distant galaxies to discern the rise of metals and dust and to unveil the co-evolution of galaxy and blackhole formation, study the Milky Way to follow the path of water from the interstellar medium to habitable worlds in planetary systems, and measure biosignatures from exoplanets. This paper describes the science drivers and how they drove key requirements for OST Mission Concept 2, which will operate between ~5 and ~600 microns with a JWST sized telescope. Mission Concept 2 for the OST study optimizes the engineering for the key science cases into a powerful and more economical observatory compared to Mission Concept 1.
The Origins Space Telescope (OST) will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. How did the universe evolve in response to its changing ingredients? How common are life-bearing planets? To accomplish its scientific objectives, OST will operate at mid- and far-infrared wavelengths and offer superlative sensitivity and new spectroscopic capabilities. The OST study team will present a scientifically compelling, executable mission concept to the 2020 Decadal Survey in Astrophysics. To understand the concept solution space, our team studied two alternative mission concepts. We report on the study approach and describe both of these concepts, give the rationale for major design decisions, and briefly describe the mission-enabling technology.
We will present a status update on the development of HIRMES, the third generation instrument for SOFIA (Stratospheric Observatory for Infrared Astronomy).
HIRMES (HIgh Resolution Mid-infrarEd Spectrometer) will cover the wavelength range between 25 micron and 122 micron with a spectral resolution of up to R~100,000. It will use two arrays of Transition Edge Sensed (TES) bolometers. One of the arrays consists of 8 16-pixel strips, for the high-resolution mode, where the pixel area and backshorts are optimized for 8 different wavelength regimes. The second detector consists of a 16x64 array with excellent sensitivity over the full wavelength range, and it will be used for the mid-resolution (R~19,000) and low-resolution (R~2,000 and R~600) observing modes. Both detector arrays will have background limited performance with NEPs of < 2E-17 W/Hz^(1/2) for the low-resolution array and < 3E-18 W/Hz^(1/2) for the high-resolution array.
HIRMES will employ several Fabry-Perot Interferometers (FPI) for the low- (R~2000), mid- (R~19,000), and high-resolution (R~100,000) observing modes. In addition, three gratings with resolutions of R~600 will be used to order-sort FPI transmission peaks, and also to obtain low resolution broad bandwidth spectra.
HIRMES's main science goals are to study the evolution of protoplanetary disks as well as to investigate the origin of Hydrogen and Deuterium in the Solar System.
The high spectral resolution observations of the HD 1-0 R(0) line at 112 micron will determine the gas mass and kinematics in protoplanetary disks, while the observations of the [OI] 63 micron and H2O lines reveal the amount of Oxygen and H20 within the snowline. Low spectral resolution observations of solid-state H20 ice features at ~43 and ~63 micron will determine the amount of water ice beyond the snowline. Measurements of the molecular hydrogen line and numerous HD lines at mid-resolution will help to estimate the H/D ratio in the Solar System. In addition, the low-resolution FPI is well suited to map fine-structure line emission from nearby galaxies.
When combined with the huge collecting area of the ELT, MOSAIC will be the most effective and flexible Multi-Object Spectrograph (MOS) facility in the world, having both a high multiplex and a multi-Integral Field Unit (Multi-IFU) capability. It will be the fastest way to spectroscopically follow-up the faintest sources, probing the reionisation epoch, as well as evaluating the evolution of the dwarf mass function over most of the age of the Universe. MOSAIC will be world-leading in generating an inventory of both the dark matter (from realistic rotation curves with MOAO fed NIR IFUs) and the cool to warm-hot gas phases in z=3.5 galactic haloes (with visible wavelenth IFUs). Galactic archaeology and the first massive black holes are additional targets for which MOSAIC will also be revolutionary. MOAO and accurate sky subtraction with fibres have now been demonstrated on sky, removing all low Technical Readiness Level (TRL) items from the instrument. A prompt implementation of MOSAIC is feasible, and indeed could increase the robustness and reduce risk on the ELT, since it does not require diffraction limited adaptive optics performance. Science programmes and survey strategies are currently being investigated by the Consortium, which is also hoping to welcome a few new partners in the next two years.