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Ground-based high-resolution, calibrated, near-infrared (NIR) imagery of the Space Shuttle STS-134 Endeavour during reentry has been obtained as part of NASA's HYTHIRM (Hypersonic Thermodynamic InfraRed Measurements) project. The long-range optical sensor package called MARS (Mobile Aerospace Reconnaissance System) was positioned in advance to acquire and track part of the shuttle re-entry. Imagery was acquired during a few minutes, with the best imagery being processed when the shuttle was at 133 kft at Mach 5.8. This paper describes the processing of the NIR imagery, building upon earlier work from the airborne imagery collections of several prior shuttle missions. Our goal is to calculate the temperature distribution of the shuttle's bottom surface as accurately as possible, considering both random and systematic errors, while maintaining all physical features in the imagery, especially local intensity variations. The processing areas described are: 1) radiometric calibration, 2) improvement of image quality, 3) atmospheric compensation, and 4) conversion to temperature. The computed temperature image will be shown, as well as comparisons with thermocouples at different positions on the shuttle. A discussion of the uncertainties of the temperature estimates using the NIR imagery is also given.

Detection and characterization of space objects require the capability to derive physical properties such as brightness temperature and reflectance. These quantities, together with trajectory and position, are often used to correlate an object from a catalogue of known characteristics. However, retrieval of these physical quantities can be hampered by the radiative obscuration of the atmosphere. Atmospheric compensation must therefore be applied to remove the radiative signature of the atmosphere from electro-optical (EO) collections and enable object characterization. The JHU/APL Atmospheric Compensation System (ACS) was designed to perform atmospheric compensation for long, slant-range paths at wavelengths from the visible to infrared. Atmospheric compensation is critically important for airand ground-based sensors collecting at low elevations near the Earth's limb. It can be demonstrated that undetected thin, sub-visual cirrus clouds in the line of sight (LOS) can significantly alter retrieved target properties (temperature, irradiance). The ACS algorithm employs non-traditional cirrus datasets and slant-range atmospheric profiles to estimate and remove atmospheric radiative effects from EO/IR collections. Results are presented for a NASA-sponsored collection in the near-IR (NIR) during hypersonic reentry of the Space Shuttle during STS-132.

The effect of ethanol on the structure of DNA confined to mica in the presence of Mg2+ was examined by varying the ethanol concentration and imaging the DNA by atomic force microscopy. Contour length measurements of the DNA show a transition from all‐B‐form at 0% ethanol to all‐A‐form at >25% ethanol. At intermediate ethanol concentrations, contour lengths suggest that individual molecules of air‐dried DNA are trapped with mixed compositions of A‐form and B‐form. The relative composition depends on the ethanol concentration. Fitting the length distributions at intermediate ethanol concentrations to a simple binomial model results in an upper bound estimate for the A‐form and B‐form domains of ∼54 bp in the individual molecules. In addition to length changes, the apparent persistence length of DNA decreases with increasing ethanol concentration. At high concen‐trations of ethanol (>20%), DNA formed several higher order structures, including flower shaped condensates and toroids.