ALBERT

Description: Recent developments in high altitude balloon platform capabilities, specifically long duration flights in excess of 50 days at over 100,000 ft and precision pointing with performance at the arc sec level or better have raised the question whether this platform can be utilized for high-value planetary science observations. In January of 2012 a workshop was held at NASA Glenn Research Center in Cleveland, Ohio to explore what planetary science can be achieved utilizing such a platform. Over 40 science concepts were identified by the scientists and engineers attending the workshop. Those ideas were captured and then posted to a public website for all interested planetary scientists to review and give their comments. The results of the workshop, and subsequent community review, have demonstrated that this platform appears to have potential for high-value science at very competitive costs. Given these positive results, the assessment process was extended to include 1) examining, in more detail, the requirements for the gondola platform and the mission scenarios 2) identifying technical challenges and 3) developing one or more platform concepts in enough fidelity to enable accurate estimating of development and mission costs. This paper provides a review of the assessment, a summary of the achievable science and the challenges to make that science a reality with this platform.

Description: Outline: Overview of Hayabusa2 mission and its target asteroid Ryugu; Spectroscopic laboratory measurements under asteroid-like conditions of carbonaceous chondrites; Recent ground-based observations of carbonaceous asteroids relevant to Ryugu; Implications of meteorite spectroscopic measurements & asteroid observations for Hayabusa2s observations of Ryugu.

Description: This report describes a study evaluating the potential for a balloon-based optical telescope as a planetary science asset to achieve decadal class science. The study considered potential science achievable and science traceability relative to the most recent planetary science decadal survey, potential platform features, and demonstration flights in the evaluation process. Science Potential and Benefits: This study confirms the cost the-benefit value for planetary science purposes. Forty-four (44) important questions of the decadal survey are at least partially addressable through balloon based capabilities. Planetary science through balloon observations can provide significant science through observations in the 300 nm to 5 m range and at longer wavelengths as well. Additionally, balloon missions have demonstrated the ability to progress from concept to observation to publication much faster than a space mission increasing the speed of science return. Planetary science from a balloon-borne platform is a relatively low-cost approach to new science measurements. This is particularly relevant within a cost-constrained planetary science budget. Repeated flights further reduce the cost of the per unit science data. Such flights offer observing time at a very competitive cost. Another advantage for planetary scientists is that a dedicated asset could provide significant new viewing opportunities not possible from the ground and allow unprecedented access to observations that cannot be realized with the time allocation pressures faced by current observing assets. In addition, flight systems that have a relatively short life cycle and where hardware is generally recovered, are excellent opportunities to train early career scientists, engineers, and project managers. The fact that balloon-borne payloads, unlike space missions, are generally recovered offers an excellent tool to test and mature instruments and other space craft systems. Desired Gondola Features: Potential gondola characteristics are assessed in this study and a concept is recommended, the Gondola for High-Altitude Planetary Science (GHAPS). This first generation platform is designed around a 1 m or larger aperture, narrow-field telescope with pointing accuracies better than one arc-second. A classical Cassegrain, or variant like Ritchey-Chretien, telescope is recommended for the primary telescope. The gondola should be designed for multiple flights so it must be robust and readily processed at recovery. It must be light-weighted to the extent possible to allow for long-duration flights on super-pressure balloons. Demonstration Flights: Recent demonstration flights achieved several significant accomplishments that can feed forward to a GHAPS gondola project. Science results included the first ever Earth-based measurements for CO2 in a comet, first measurements for CO2 and H2O in an Oort cloud comet, and the first measurement of 1 Ceres at 2.73 m to refine the shape of the infrared water absorption feature. The performance of the Fine Steering Mirror (FSM) was also demonstrated. The BOPPS platform can continue to be leveraged on future flights even as GHAPS is being developed. The study affirms the planetary decadal recommendations, and shows that a number of Top Priority science questions can be achieved. A combination GHAPS and BOPPS would provide the best value for PSD for realizing that science.

Description: The National Aeronautics and Space Administration (NASA) and the planetary science community have recently been exploring the potential contributions of stratospheric balloons to the planetary science field. A study that was recently concluded explored the roughly 200 or so science questions raised in the Planetary Decadal Survey report and found that about 45 of those questions are suited to stratospheric balloon based observations. In September of 2014, a stratospheric balloon mission called BOPPS (which stands for Balloon Observation Platform for Planetary Science) was flown out of Fort Sumner, New Mexico. The mission had two main objectives, first, to observe a number of planetary targets including one or more Oort cloud comets and second, to demonstrate the applicability and performance of the platform, instruments, and subsystems for making scientific measurements in support planetary science objectives. BOPPS carried two science instruments, BIRC and UVVis. BIRC is a cryogenic infrared multispectral imager which can image in the.6-5 m range using an HgCdTe detector. Narrow band filters were used to allow detection of water and CO2 emission features of the observed targets. The UVVis is an imager with the science range of 300 to 600 nm. A main feature of the UVVis instrument is the incorporation of a guide camera and a Fine Steering Mirror (FSM) system to reduce image jitter to less than 100 milliarcseconds. The BIRC instrument was used to image targets including Oort cloud comets Siding Spring and Jacques, and the dwarf planet 1 Ceres. BOPPS achieved the first ever earth based CO2 observation of a comet and the first images of water and CO2 of an Oort cloud comet (Jacques). It also made the first ever measurement of 1Ceres at 2.73 m to refine the shape of the infrared water absorption feature on that body. The UVVis instrument, mounted on its own optics bench, demonstrated the capability for image correction both from atmospheric disturbances as well as some of the residual motion from the gondola that was not addressed by the gondolas coarse pointing systems. The mission met its primary science and engineering objectives. The results of the BOPPS mission will feed into the body of science knowledge but also feed into future planning for more science from balloon-borne platforms. A notional platform called Gondola for High-Altitude Planetary Science (GHAPS) has been explored and this concept platform can address a number of important decadal questions. This paper provides a summary of the assessment of potential balloon borne observations for planetary science purposes including where potential science contributions can be expected, the necessary performance characteristics of the platform, and other features required or desired. The BOPPS mission is summarized including descriptions of the main elements and key science and engineering results. The paper then briefly describes GHAPS, and the salient features that can make it a valuable tool for future planetary observations.

Description: NASA and the planetary science community have been exploring the potential contributions approximately 200 questions raised in the Decadal Survey have identified about 45 topics that are potentially suitable for addressing by stratospheric balloon platforms. A stratospheric balloon mission was flown in the fall of 2014 called BOPPS, Balloon Observation Platform for Planetary Science. This mission observed a number of planetary targets including two Oort cloud comets. The optical system and instrumentation payload was able to provide unique measurements of the intended targets and increase our understanding of these primitive bodies and their implications for us here on Earth. This paper will discuss the mission, instrumentation and initial results and how these may contribute to the broader planetary science objectives of NASA and the scientific community. This paper will also identify how the instrument platform on BOPPS may be able to contribute to future balloon-based science. Finally the paper will address potential future enhancements and the expected science impacts should those enhancements be implemented.