FASA - Fire Airborne Spectral Analysis of Natural Disasters

At present the authors are developing the system FASA, an airborne combination of a Fourier Transform Spectrometer and an imaging system. The aim is to provide a system that is usable to investigate and monitor emissions from natural disasters such as wild fires and from volcanoes. Besides temperatures and (burned) areas FASA will also provide concentration profiles of the gaseous combustion products. These data are needed to improve the knowledge of the effects of such emissions on the global ecosystem. The paper presents a description of the instrumentation, the data evaluation procedure and shows first results of retrieval calculations based on simulated spectra

Conception and State of the Radiometric Analysis Breadboard (RAB) for the Mercury Radiometer and Thermal Infrared Spectrometer (MERTIS)

As a part of the ESA deep space mission to mercury - BepiColombo - investigations of mercury´s surface layer using a push-broom thermal infrared imaging spectrometer (MERTIS) with a high spectral resolution is planned. One of the scientific goals is the measurement of Christiansen Features which are emissivity maxima resulting from rapid changes in the real part of the mineral´s refractive index. Their positions within the spectral range of 7-14µm deliver information about mineralogical compositions. For these measurement MERTIS needs to have a high spectral resolution of 90nm. The planet will be mapped with a resolution of 500m and a S/N ratio of at least 100. For the measurement of the surface radiation a micro-bolometer detector array will be used. A detectivity of 1.0E9 is required. High sensitive TIR systems commonly use cooled detectors with a large mass budget and high electrical power consumption. One of the challenges of MERTIS is the use of an uncooled micro-bolometer detector. The development of MERTIS is currently in an early phase but a breadboard concept will be presented. Special attention is payed to the first of two phases of the breadboard concept: - The Radiometric Breadboard (RAB) has been configured for the development of the opto-electronical components and for the investigation of radiometric calibration methods and algorithms. The design of the RAB is already a spectrometer configuration but it cannot reach the performance the technical and scientific requirements demand. - The Spectro-Radiometric Breadboard (SRB) will be implemented for investigations of the performances of the optics and detector of MERTIS. Relevant components have to be developed and validated particularly in the spectral domain. The SRB will be the prototype of MERTIS

MERTIS - the design of a highly integrated IR imaging spectrometer

A belief that Mercury carries unique clues to the origin and evolution of the Solar System has driven the interest for detailed studies of the innermost planet. Here surface mineralogy requires information of the thermal inertia asking for observations by space borne instruments in the near IR and the thermal IR domain. With a background of several instrument developments in the past the German Aerospace Center in Berlin proposed for ESA’s deep space mission BepiColombo an imaging spectrometer which meets the challenges of limited technical resources and a very special operational environment. An 80-channel push broom-type spectrometer has been drafted and it s development has been started under the name MERTIS (MERcury Thermal Infrared Spectrometer). It is based on modern European un-cooled micro-bolometer technology and all-reflective optics design. The operation concept principle is characterised by intermediate scanning of the planet, free space and black bodies as calibration targets. A miniaturised radiometer is included for low level temperature measurements. Altogether the system shall fit into a CD-package sized cube and weigh less than 3 kg. The paper will present the instrument architecture of MERTIS, its design status and results of laboratory investigations with the first components being built

A microsatellite platform for hot spot detection

The main payload of the BIRD micro-satellite is the newly developed Hot Spot Recognition System. Its a dual-channel instrument for middle and thermal infrared imagery based on cooled MCT line detectors. The miniaturisation by integrated detector/ cooler assemblies provides a highly efficient design. Since the launch in October 2001 from SHAR/ India the BIRD payload, claiming 30% of the BIRD mass of 92kg, is fully operational. Among others forest fires (Australia), volcanoes (Etna, Chile) and burning coal mines (China) have been detected and their parameters like size, temperature and energy release could be determined. As the status of the payload system is satisfactorily it has a potential to be applied in new missions with the help of modern detector technology

BIRD detection and analysis of high-temperature events: first results

The primary mission objective of a new small Bi-spectral InfraRed Detection (BIRD) satellite, which was put in a 570 km circular sun-synchronous orbit on 22 October 2001, is detection and quantitative analysis of high-temperature events (HTE) like fires and volcanoes. A unique feature of the BIRD mid- and thermal infrared channels is a real-time adjustment of their integration time that allows a HTE observation without sensor saturation, preserving a good radiometric resolution of 0.1-0.2 K for pixels at normal temperatures. This makes it possible: (a) to improve false alarm rejection capability and (b) to estimate HTE temperature, area and radiative energy release. Due to a higher spatial resolution, BIRD can detect an order of magnitude smaller HTE than AVHRR and MODIS. The smallest verified fire that was detected in the BIRD data had an area of ~12 m2. The first BIRD HTE detection and analysis results are presented including bush fires in Australia, forest fires in Russia, coal seam fires in China, and a time-varying thermal activity at Etna

FOCUS on ISS-Sensor and Data Fusion for Earth Observation from Space

Earth observation systems from space platforms in general employ remote sensing instruments of a specific type (imaging, spectrometric, etc.) in a specific spectral band (visible, infrared, microwave, etc.) to observe a specific earth feature (atmospheric trace gas distribution, vegetation coverage, ocean surface temperatures, etc). These systems deliver data to ground stations for storage and utilisation. Various steps of processing will be applied to the data on ground to extract the desired information. In such way many parameters are monitored independently from each other with respect to time and space, however. There are applications where simultaneous operation of different sensor types/spectral regions and combined data evaluation could significantly enhance amount and quality of information derived and even add new onboard (in space) functionality to space remote sensing systems. FOCUS, an ESA earth observation sensor system candidate for the early utilisation phase of the International Space Station (ISS), is intended to demonstrate such a new approach. The system is dedicated to High Temperature Event (HTE) investigation (forest fires, volcano activity, etc.). It will incorporate autonomous HTE detection and geo-location in near real time as unique onboard capability and provide quantitative HTE and background classification and HTE plume emission products analysis (temperatures, gas and aerosol distribution). As such it will aid in understanding HTE dynamics and be capable to support activities towards future natural disaster monitoring and early warning systems. It represents a possible next step in advancing earth observation systems

FASA - Fire Airborne Spectral Analysis of Natural Disasters

At present the authors are developing the system FASA, an airborne combination of a Fourier Transform Spectrometer and an imaging system. The aim is to provide a system that is usable to investigate and monitor emissions from natural disasters such as wild fires and from volcanoes. Besides temperatures and (burned) areas FASA will also provide concentration profiles of the gaseous combustion products. These data are needed to improve the knowledge of the effects of such emissions on the global ecosystem. The paper presents a description of the instrumentation, the data evaluation procedure and shows first results of retrieval calculations based on simulated spectra

Der Kleinsatellit BIROS in der FireBIRD Mission

Dieser Bericht enthält eine detaillierte Abhandlung des gesamten Entwicklungsprozesses des Bi-spektralen Infrarot-Optischen Systems (BIROS) in der FireBIRD Mission, beginnend mit der wissenschaftlichen Aufgabenstellung zur Detektion und Bewertung von Hochtemperaturereignissen (HTE) aus dem Weltraum über die Auslegung des IR-Kamerasystems als primäre Nutzlast von BIROS, seiner Sekundärnutzlasten, des BIROS Satellitenbusses, dem Nutzerinterface zur Datenanforderung bis hin zu ausgewählten Anwendungsbeispielen der FireBIRD Datenprodukte. Es wird neben der technischen Beschreibung der Subsysteme des Satelliten und der bi-spektralen IR-Kamera, mit Bändern im mittleren Infrarot (MIR) und im thermalenInfrarot (TIR) die adaptive Anpassung der radiometrischen Dynamik der IR-Signaltrakte erklärt. Diese stellt ein Alleinstellungsmerkmal dar im Hinblick auf die bildhafte Erkennung und Bewertung von Feuern oder heißer Lava, welche Temperaturen zwischen 300 °C und 1300 °C erreichen, im sogenannten Sub-Pixelbereich. Anhand von verschiedenen Anwendungsbeispielen wird aufgezeigt, dass mit der IR-Kamera kleine Feuer von nur 10 m2 Ausdehnung zu erkennen sind und gleichzeitig bei der Beobachtung von riesigen Busch-bränden oder groß- flächigen Lavaströmen die IR-Kamera Signaltrakte nicht 'in die Sättigung' gehen, d.h. das Feuersignal nicht begrenzen. Aus der Beobachtung HTE einerseits und von NormalTemperatur-Phänomenen (NTP) konnten die adaptiven Dynamikbereiche für die MIR- und TIRBänder der Kamera nachgwiesen werden, die von keinem anderen IR-Kamaerasystem eines Kleinsatelliten bekannt sind. Die mit BIROS gesammelten Erfahrungen erlauben Schlussfolgerungen für zukünftige Kleinsatellitenmissionen zur räumlich und radiometrisch höher auflösenden Erdbeobachtung im MIR und TIR