Addressing environmental and atmospheric challenges for capturing high-precision thermal infrared data in the field of astro-ecology

Using thermal infrared detectors mounted on drones, and applying techniques from astrophysics, we hope to support the field of conservation ecology by creating an automated pipeline for the detection and identification of certain endangered species and poachers from thermal infrared data. We test part of our system by attempting to detect simulated poachers in the field. Whilst we find that we can detect humans hiding in the field in some types of terrain, we also find several environmental factors that prevent accurate detection, such as ambient heat from the ground, absorption of infrared emission by the atmosphere, obscuring vegetation and spurious sources from the terrain. We discuss the effect of these issues, and potential solutions which will be required for our future vision for a fully automated drone-based global conservation monitoring system.Comment: Published in Proceedings of SPIE Astronomical Telescopes and Instrumentation 2018. 8 pages, 3 figure

High-resolution SOFIA/EXES Spectroscopy of Water Absorption Lines in the Massive Young Binary W3 IRS 5

We present in this paper mid-infrared (5-8~$\mu$m) spectroscopy toward the massive young binary W3~IRS~5, using the EXES spectrometer in high-resolution mode ($R\sim$50,000) from the NASA Stratospheric Observatory for Infrared Astronomy (SOFIA). Many ($\sim$180) $\nu_2$=1--0 and ($\sim$90) $\nu_2$=2-1 absorption rovibrational transitions are identified. Two hot components over 500 K and one warm component of 190 K are identified through Gaussian fittings and rotation diagram analysis. Each component is linked to a CO component identified in the IRTF/iSHELL observations ($R$=88,100) through their kinematic and temperature characteristics. Revealed by the large scatter in the rotation diagram, opacity effects are important, and we adopt two curve-of-growth analyses, resulting in column densities of $\sim10^{19}$ cm$^{-2}$. In one analysis, the model assumes a foreground slab. The other assumes a circumstellar disk with an outward-decreasing temperature in the vertical direction. The disk model is favored because fewer geometry constraints are needed, although this model faces challenges as the internal heating source is unknown. We discuss the chemical abundances along the line of sight based on the CO-to-H$_2$O connection. In the hot gas, all oxygen not locked in CO resides in water. In the cold gas, we observe a substantial shortfall of oxygen and suggest that the potential carrier could be organics in solid ice.Comment: Accepted for publication in ApJ. 34 pages, 13 figures, and 14 tables. Comments are more than welcome

Optimising observing strategies for monitoring animals using drone-mounted thermal infrared cameras

The proliferation of relatively affordable off-the-shelf drones offers great opportunities for wildlife monitoring and conservation. Similarly the recent reduction in cost of thermal infrared cameras also offers new promise in this field, as they have the advantage over conventional RGB cameras of being able to distinguish animals based on their body heat and being able to detect animals at night. However, the use of drone-mounted thermal infrared cameras comes with several technical challenges. In this paper we address some of these issues, namely thermal contrast problems due to heat from the ground, absorption and emission of thermal infrared radiation by the atmosphere, obscuration by vegetation, and optimizing the flying height of drones for a best balance between covering a large area and being able to accurately image and identify animals of interest. We demonstrate the application of these methods with a case study using field data, and make the first ever detection of the critically endangered riverine rabbit (Bunolagus monticularis) in thermal infrared data. We provide a web-tool so that the community can easily apply these techniques to other studies (http://www.astro.ljmu.ac.uk/~aricburk/uav_calc/)

Spatial and temporal variations in the CH4 homopause altitude at Jupiters mid-to-high latitudes

International audienceJupiters magnetosphere and the external space environment strongly influence the thermal structure, chemistry and dynamics of the neutral atmosphere. Using TEXES (Texas Echelon Cross Echelle Spectrograph) observations measured in April and August 2019 from the IRTF, we demonstrated that the CH4 homopause altitude, henceforth CHA, was 70 130 km higher in altitude inside Jupiters northern main auroral oval compared to elsewhere on the planet (Sinclair et al., 2020, PSJ 1, 85). This suggests energy from Jupiters magnetosphere ultimately drives vertical winds and turbulence, which transports CH4 and its photochemical by-products to higher altitudes. The CHA is also an uncertain degree of freedom in the analysis of Jupiters ultraviolet auroral emissions, which are under current investigation by the Juno mission, as well as by Hubble and Hisaki. The goal of this work is to provide independent and stringent constraints on the CHA to best support Junos investigation of the ultraviolet auroral emissions and their connection to magnetospheric dynamics. We present an analysis of high-resolution mid-infrared spectra recorded by SOFIA-EXES on June 8 18, 2021 and IRTF-TEXES on June 28-29, 2021, which provide significant advances on previous work presented by Sinclair et al., 2020. In contrast to the TEXES observations in 2019, both sets of data in 2021 sample longitudes inside the southern auroral oval, which allows the CHA to be constrained in this region. A comparison of the results inside the northern main oval with those measured in 2019 allows the temporal variability of the CHA inside Jupiters northern auroral oval to be quantified. Although at a coarser spatial resolution, EXES measurements probe higher in Jupiters stratosphere/mesophere, which is expected to provide more stringent upper limits on the CHA in Jupiters main ovals. In addition, observations in both 2019 and 2021 will be re-analyzed with an updated model grid that extends to lower CHAs. This provides more stringent constraints on the CHA derived outside the main ovals, which in turn allows the contrast in CHA inside and outside the main auroral ovals to be more accurately quantified

Spatial and temporal variations in the CH4 homopause altitude at Jupiters mid-to-high latitudes

International audienceJupiters magnetosphere and the external space environment strongly influence the thermal structure, chemistry and dynamics of the neutral atmosphere. Using TEXES (Texas Echelon Cross Echelle Spectrograph) observations measured in April and August 2019 from the IRTF, we demonstrated that the CH4 homopause altitude, henceforth CHA, was 70 130 km higher in altitude inside Jupiters northern main auroral oval compared to elsewhere on the planet (Sinclair et al., 2020, PSJ 1, 85). This suggests energy from Jupiters magnetosphere ultimately drives vertical winds and turbulence, which transports CH4 and its photochemical by-products to higher altitudes. The CHA is also an uncertain degree of freedom in the analysis of Jupiters ultraviolet auroral emissions, which are under current investigation by the Juno mission, as well as by Hubble and Hisaki. The goal of this work is to provide independent and stringent constraints on the CHA to best support Junos investigation of the ultraviolet auroral emissions and their connection to magnetospheric dynamics. We present an analysis of high-resolution mid-infrared spectra recorded by SOFIA-EXES on June 8 18, 2021 and IRTF-TEXES on June 28-29, 2021, which provide significant advances on previous work presented by Sinclair et al., 2020. In contrast to the TEXES observations in 2019, both sets of data in 2021 sample longitudes inside the southern auroral oval, which allows the CHA to be constrained in this region. A comparison of the results inside the northern main oval with those measured in 2019 allows the temporal variability of the CHA inside Jupiters northern auroral oval to be quantified. Although at a coarser spatial resolution, EXES measurements probe higher in Jupiters stratosphere/mesophere, which is expected to provide more stringent upper limits on the CHA in Jupiters main ovals. In addition, observations in both 2019 and 2021 will be re-analyzed with an updated model grid that extends to lower CHAs. This provides more stringent constraints on the CHA derived outside the main ovals, which in turn allows the contrast in CHA inside and outside the main auroral ovals to be more accurately quantified