BX35 – CHAOS (CHerenkov Atmospheric Observation System)
Kiel University, Germany
Launch Date: October 2024
The Earth is continuously exposed to high-energy charged particles, so-called Galactic Cosmic Rays (GCRs). When these particles hit the Earth’s atmosphere, they create a cascade of secondary particles. The Cherenkov Atmospheric Observation System (CHAOS) uses a new detector design developed by a team of students at the Department of Extraterrestrial Physics at Kiel University to measure the different particle species of the primary GCRs above the so called Regener-Pfotzer Maximum. To perform these measurements a combination of multiple Solid State Detectors (SSDs) and a Bismuth Germanium Oxide (BGO) scintillator is used to measure the energy depositions of the particles. The use of an additional Cherenkov aerogel scintillator allows to separate between light and heavy particles, such as electrons and ions.
Because electrons are much lighter than ions, electrons with energies above ∼1.1 MeV will trigger the Cherenkov detector whereas ions with the same energy are much slower and will not trigger the Cherenkov detector.
BX33 – ALMA (Atmospheric Laser Measurements of Aerosols)
Luleå University of Technology
Launch Date: 21st September 2023
ALMA is part of the student projects at LTU, Sweden with the main purpose of developing atmospheric research in the Norrbotten area. The scientific objectives include finding a correlation between density, size and composition of aerosols in the troposphere and stratosphere and the global volcanic activity, as well as studying the change in ozone amount generated by such activity. The experiment follows two different methods to acquire data. Firstly, the development and utilization of an Open-Source particle counter will be done. Secondly, an off the shelf Ozone Sonde instrument will be implemented. The measurements obtained will be compared with databases from Sentinel-5p, Ozone Monitoring Instrument (OMI) and Ozone Mapping Profiling Suite (OMPS) satellite missions, previous to a large volcanic activity phase.
The idea for the project came after the Cumbre Vieja volcano eruption on the Spanish island of La Palma in September 2021. The project is encouraged by a natural event that cannot be predicted and which has worldwide consequences for the climate, even after a long period of time. Therefore, the contribution of recent information regarding environmental impacts after volcanic eruptions is intended. By implementing two different methods to retrieve sufficient information, the scientific aims of the experiment will be satisfied. On top of that, one technical objective of developing a novel particle counter will be tackled. This instrument will be a basis for future balloon borne missions.
BX33 – CASTOR (Combined Analysis Sensor for Trioxygen and Oxygen Richness)
Technische Universität Dresden
Launch Date: 21st September 2023
An important part of atmospheric research is the investigation of the ozone concentration and the relative humidity in the unique environment of the lower stratosphere. The ozone layer protects our flora and fauna from dangerous radiation damage and is therefore essential for life on earth. Human made chlorofluorocarbons led to a strong depletion of natural ozone and still affects the ozone layer today. For this reason, the ozone concentration is regularly measured and analyzed. Often the measurements are carried out by means of a balloon at a height of 15-30 km, where about 90 % of the atmospheric ozone is located. The relative humidity is among other things important for our daily weather report and is therefore even more often measured than the ozone concentration. To measure the relative humidity at sea level is quite easy and can be executed by commercial hygrometers. The measurement of the relative humidity in the lower stratosphere on the other hand is rather difficult since the humidity at a height of 15-30 km is so low (< 3 %) that it is almost impossible to be measured with conventional technology. The CASTOR experiment aims to field test miniaturized ozone and relative humidity sensors developed and improved at the Institute for Aerospace Technology (ILR) at the TU Dresden. Both sensors are manufactured using the cost-effective thick-film process and are characterized by their robustness and short response times. The recording of the data under real conditions within the framework of BEXUS will lead to the completion of the sensors and will give us a realistic impression of the ozone concentration and the relative humidity in the special environment of the stratosphere. The development of the two sensors will help to simplify the measurement of the two important factors in the future.
BX32 – HERCCULES (Heat-transfer and Environment Radiative and Convective Characterization in a University Laboratory for Experimentation in the Stratosphere)
Universidad Politécnica de Madrid
Launch Date: 24th September 2023
Ballooning applications are continuously improving. They have become a very demanding platform for many purposes such as technology demonstration, solar physics, Earth observations, etc. Designs are becoming more and more complex with time. For this reason, characterizing the thermal behaviour of these platforms not only during the floating phase but also during the ascent phase is essential to fulfil the requirements. For this reason, HERCCULES aims at measuring the albedo, the Outgoing Longwave Radiation, the sky temperature, and the solar irradiance during both the ascent and float phases. This will allow the validation of a developed methodology for selecting the worst-case conditions for stratospheric balloon thermal analysis based on Real-data observation. In addition, HERCCULES carries some experiments to quantify the convective heat transfer on heated plates as well as to measure the relative wind speed on an external surface. This will help us to understand how convection behaves in this kind of platforms and temperature results will be used to correlate the thermal models developed with ESATAN-TMS.
RX29 – RaPTeX (Radiologic Particle Telescope eXperiment)
UiT The Arctic University of Norway, Norway
Launch Date: 01 April 2023
The objective of RaPTeX (Radiologic Particle Telescope eXperiment) is to conduct atmospheric research by measuring charged particles (pions, muons, etc) during the REXUS flight. This shall give us the necessary data to study the flux density of subatomic particles in different atmospheric layers. Our experiment uses semiconductor sensors and a radiation-hard application specific integrated circuit (ASIC). The technological challenge of this demonstration is to build our experiment in a 80 x 80 x 80 mm box to emulate the technical restraints of a 1U CubeSat and to use commercial off the shelf components (COTS) while still making it reliably enough to withstand the forces expected during the launch. This way RaPTeX is a step on the road to develop a small and simple particle telescope for CubeSats. The scientific data we collect during the REXUS flight will be used to verify the success of the experiment.
BX31 – FaNS (Fast Neutron Spectrometer)
Christian-Albrechts-Universität zu Kiel, Germany
Launch Date: 29th September 2021
The interaction of primary cosmic rays with the molecules of the Earth’s atmosphere leads to a complex radiation field which consists among others of neutrons. The Fast Neutron Spectrometer (FaNS) has been developed to determine the flux of fast neutrons within the Earth’s atmosphere. The instrument consists out of a boron-doped plastic scintillator which is optimized for the energy range from about 0.5 MeV to above 10 MeV. In this work the practicality of this lightweight and compact instrument will be shown in the extreme environment of Earth’s stratosphere onboard a BEXUS Balloon.
FaNS Student Experiment Document
BX30 – ECO-WISE (Environmental Computations WIth low coSt sEt-up)
Aristotle University of Thessaloniki, Greece
Launch Date: 30th September 2021
Climate change is a global concern and greenhouse gases are the main factors causing it. The ECO WISE experiment aims to examine the main mechanisms that contribute to the aggravation of this phenomenon.
A vertical and horizontal distribution of the most important trace gases (CO2, CH4, O3) will be estimated during the ascending and descending phase as well as the floating time of the stratospheric balloon flight. As alternative methods like satellites or other stratospheric balloon methods already succeed in this field, we are mindful to present a low-cost set-up for measuring atmospheric gases. In order to measure those gases we propose commercial ground based sensors while securing a favorable environment for their proper function during the flight.
The proposed set up holds together various mechanisms for collecting atmospheric data and these mechanisms are working together and directing gradually the air sample through a path.
In the future, this set-up can be extended with alternative sensor options, for various measurements in balloon flights. It provides independence in interested institutes in terms of budget, project execution time and disengagement from third parties. Our goal is to be spread around the world opposing to already existing methods.
ECO-WISE Student Experiment Document v5-1
BX30 – O-Zone
University of Padua, Italy
Launch Date: 30th September 2021
The aim of our experiment is the study of air pollutants of anthropogenic and natural origin through compact device that can quickly intervene in the study of restricted areas.
The necessity of being and feel ourselves part of the change and the recent and dramatic events, led us to think about a system that can improve, maybe a little, the study and the thought of intervention on the environmental situation.
The first step of our experiment consists in collecting air at different heights (from 5 to 35 km) and trapping the particles of interest (solid particles, pollutants such as CFCs, NOx, SOx, PM and others) with a system of filters and a sealed air collector (canister). To compare and enrich those data we will use different types of sensors.
After the flight of the balloon, we will be able to analyse the samples. Moreover, thanks to the values of temperature and pressure, we will be able not only to know more about air composition at each altitude, but also to build dispersion curves and models for each analyte. Another goal of our experiment is to know the percentages of ozone and UV radiation in the quotas of interest. This would allow us to predict possible reactions in situ and to think of solutions for intervention or prevention.
Nowadays many of the compounds called Freons have already reached high atmospheric stages. The heaviest, the brominated compounds, have a slower rise. Our experiment also aims to theorise models to understand the rise of these molecules and predict harmful impacts on the ozone ecosystem.
Finally, our experiment is meant to be a smart way to monitor and predict potentially dangerous situations like uncontrolled emissions, calamities and to make sure that companies and industries work in compliance with regulations to protect the environment, the agriculture sectors and human health.
O-Zone Student Experiment Document v5-1
BX28 – DESTINY (Detection of Earthquakes through a STratospheric INfrasound studY)
École polytechnique, France
Launch Date: 25 October 2019
The internal structure of terrestrial planets such as Mars, Earth and Venus contain key information about the Universe. To investigate the history of our solar system, it is necessary to understand these planets’ evolution. In this sense, Venus is particularly interesting, being similar on many aspects to Earth. Yet, the extreme conditions on its surface (460 °C and 92 atm) make it impossible today to use long-lasting landers. The challenge is thus to find a method to probe Venus’ structure without ground sensors.
One solution, proposed by researchers from ISAE-SUPAERO and JPL, consists in using balloon-borne barometers to study the infrasonic waves produced by seismic events. The interest of this technique is that at an altitude of 55 km, Venus’ atmosphere presents earthly conditions: a pressure of 0.5 atm and a temperature of 27 °C. Besides, infrasound signals are amplified throughout their propagation toward the upper layers of the atmosphere – due to the conservation of energy and the
decrease in air density – which eases their detection at high altitudes.
The DESTINY experiment aims at testing this method on Earth’s stratosphere. Our goal is to characterize the infrasonic background of the atmosphere to be able to recognize specific signals and locate their origin. As infrasound events we will use ground explosions, but we will also look for other specific signals. To do so, we will measure the phase difference between the signals detected by distant barometers, and will process it to locate their origin.
DESTINY Student Experiment Document v5-1
BX28 – GAMMA-VOLANTIS (Nafion ozone sensor field test)
Technische Universität Dresden, Germany
Launch Date: 25 October 2019
The measurement of the composition of the lower stratosphere plays an important role in atmospheric research. Novel miniaturized sensors: solid-state electrolyte for ozone, and resistive for relative humidity, will be tested under real conditions within the framework of BEXUS. Among their unique properties, the solid-state electrolyte sensors distinguish themselves by their robustness and short response time. Commercially available, miniaturized ozone sensors show a cross sensitivity to humidity. Using NAFION as an electrolyte eliminates this cross sensitivity due to the unique role of water in enabling the electrolyte to function as an ionic conductor [1]. The resistive humidity sensor is based on the change of the electrical behavior of multi-walled carbon nanotubes (MWCNT) embedded in a NAFION matrix. Due to the NAFION’s ability to take up 30%wt. of water [1], the contact area between two CNTs is enlarged. In addition, molecules are adsorbed on the CNT’s surface, resulting in an increase in resistivity. The partial pressure dependence of the permeability of water in NAFION can be used to significantly reduce the sensor’s response time. The sensors will be heated to maintain constant boundary conditions. The sensors are manufactured using low-cost thick film technology in a multilayer design, and multiple variations will be tested during the mission. The sensors will be characterized using a uniquely designed test rig in the laboratory of the ILR prior to, and after the mission.
BX28 – OOXYGEN (Organic oxygen sensor reference experiment)
Technische Universität Dresden, Germany
Launch Date: 25 October 2019
As systematic data collection is of key importance to a deeper understanding of the geophysical systems of the Earth the demand for portable and versatile sensing technologies will be continuously high in the coming years. Especially the examination of processes within the atmosphere will contribute to understanding climate development and environmental effects of human activities. Team OOXYGEN’s goal is implementing, testing and validation of an organic optical oxygen sensor in order to provide an alternative sensor technology for atmospherical research.
BX27 – LUSTRO (Light and Ultraviolet Strato-and Tropospheric Radiation Observer)
Warsaw University of Technology, Poland
Launch Date: 18 October 2018
The “Light and Ultraviolet Strato-and-Tropospheric Radiation Observer” experiment is based on the idea of completion of satellite- and ground-based measurements of ultraviolet radiation observation (>200nm) during balloon flight. Collected data will be examined in terms of differences in reflection and absorption in the troposphere and lower layers of the stratosphere, especially through the clouds. Measurements part is composed of two low-cost, simultaneously working rotating-mirror cameras, creating a pair of images; the radiation-sensitive elements are UV/VIS photodiodes. On board computer collects additional data from IMU (inertial measurement unit), RTC (real time clock) and encoders. In analysis the three-dimensional presentation of the gathered data shall be presented. Finally, it will be compared with ground and satellite measurements. It should prove itself to be more intuitive for the experiment crew and other researchers to define the structures of the UV reflection and absorption regions. Typical, full-semiconductor matrix UV cameras present high financial issues – LUSTRO is to overcome these issues, providing an affordable way of creating scientifically valuable data of ultraviolet structures in the atmosphere.
Student Experiment Documentation v5-1
BX26 – TUBULAR (Alternative AirCore Atmospheric Trace Gas Sampling)
Luleå University of Technology, Sweden
Launch Date: 17 October 2018
Carbon dioxide (CO2), methane (CH4), and carbon monoxide (CO) are three main greenhouse gases emitted by human activities. Developing a better understanding of their contribution to greenhouse effects requires more accessible, flexible, and scalable air sampling mechanisms. A balloon flight is the most cost effective mechanism to obtain a vertical air profile through continuous sampling between the upper troposphere and the lower stratosphere. However, recovery time constraints due to gas mixture concerns geographically restrict the sampling near existing research centers where analysis of the recovered samples can take place. The TUBULAR experiment is a technology demonstrator for atmospheric research supporting an air sampling mechanism that would offer climate change researchers access to remote areas by minimizing the effect of gas mixtures within the collected samples so that recovery time is no longer a constraint.
The experiment will include a secondary sampling mechanism that will serve as reference against which the proposed sampling mechanism can be validated.
Student Experiment Documentation v5-0
RX26 – PRIME (Plasma measuRements wIth Micro Experiment)
Royal Institute of Technology, Sweden
Launch Date: March 2019
The PRIME project aims to demonstrate a miniaturised scientific payload for plasma measurements in the lower ionosphere. The Free Falling Unit (FFU) payloads are ejectable from the RMU. Each module consists of recovery and experiment units, which are electrically and mechanically separate, so that the recovery unit can be adapted in the future to different experiments. The geometry of the FFU is designed to be compatible with future ‘DART’ rockets. The recovery unit consists of a parachute along with its deployment mechanism and localization system, i.e. GPS and transmitters used to send information for recovery. The experiment unit will consist of the Langmuir probes, voltage sweeper implemented within the FPGA, DAC, amplifiers, current-to-voltage converter and ADC, and associated memory. There will be two FFUs with four cylindrical Langmuir probes each. Three of the probes will be fixed bias and one will be in swept bias. The probes will measure electron plasma current to deduce plasma parameters at the sub-meter scale. These measurements will then be validated against incoherent radar scatter data (EISCAT) and models.
BX25 – HAMBURG (High Altitude Meteoroids-dust-catching-Balloon constrUcted by a Revolutionary Generation)
Technical University of Hamburg, Germany
Launch Date: 20 October 2017
The goal of the experiment ‘HAMBURG’ (High Altitude Meteoroid-dust-catching Balloon constrUcted by a Revolutionary Generation) deals with the gathering and analysing of iron-nickel-containing micrometeoroid, meteorid- and cosmic dust in many atmospheric layers (primary stratosphere) and the creation of a heightparticleconcentration-profile. The module is prepared with neodymium magnets in an isolated revolver-cylinder. On the ground-station the cylinder is turned to an isolated revolver-layer and it turnes a layer with a barometer every 5 to 6 km.
BX25 – IRIS (Infra-Red albedo measurements In Stratosphere)
Luleå University of Technology, Sweden
Launch Date: 20 October 2017
IRIS aims to measure the incoming radiation from the Sun and Earth’s reflection from snow covered surfaces, vegetation in the Arctic and different types of clouds. The spectral signature characteristic of terrestrial vegetation, known as “red edge” will also be examined. The expected outcomes of IRIS are to detect the variations of the albedo between snow and cold white clouds, distinguish healthy vegetation from non-healthy vegetation as well as finding a correlation between albedo and the decrease of the cryosphere. Measurements are performed by photodiodes pointing upwards and downwards, which cover the visible and IR spectrum. A camera facing downwards will define the surface directly beneath. Sensors pointing up and down will allow to differentiate the intensity from these two directions depending on the altitude. A high-altitude balloon is required to distinguish the different albedo of cold white clouds and snow, as other remote sensing methods are not as effective. Measuring the radiation balance of the Arctic region will aid in future numerical models describing the radiative balance and the climate all over planet Earth. To achieve this, one or more of several already existing models will be used as reference. The selected reference model will be decided once the experiment has been successfully completed and data has been recovered.
BX24 – EXIST (Examination of Infrasound in the Stratosphere and Troposphere)
Luleå University of Technology, Sweden
Launch Date: 18 October 2017
Low frequency sound can travel thousands of kilometres, and can be used to predict severe weather conditions, meteors, earthquakes, and other interesting phenomena’s, all with different applications and areas of research. As of today, most infrasound measurements have been performed at ground and sea level, but those are unlikely to capture the entirety of the infrasound spectrum because of interference from objects on the ground. Previous airborne measurements have been done in 2014 and 2015 over the southern United States, leaving the question of stratospheric infrasound in the rest of the world open. This provides an opportunity to listen for infrasound above the Arctic Circle in an area with a highly developed network of ground stations, which will be used to compare with the stratospheric results. Infrasound, temperature, pressure, wind velocity and direction will be measured with two independent sensor boxes. All data obtained will be analysed with software used in the International Monitoring System and software developed at the Swedish Institute of Space Physics, with help from Dr. Johan Kero. This will be compared with data from previous measurements in collaboration with Dr. Daniel Bowman, the Student Leader of the High Altitude Student Payload flights in the United States, and Professor Yamamoto, Kochi University of Technology, who will provide the group with microphones developed by SAYA Inc in collaboration with JAXA. In the future, a deeper understanding of low frequency sounds at stratospheric altitudes may help in examining the weather conditions and geological activity on other planets, especially on Mars as the pressure in the Earth’s stratosphere is at the same order of magnitude as the atmospheric pressure close to the surface of Mars.
RX22 – AtmoHIT (Atmospheric Hetrodyne Interferometer Test)
Research Centre Jülich/ University of Wuppertal, Germany
Launch Date: 16 March 2017
The experiment AtmoHIT has the goal to verify the AtmoCube-1 remote sensing instrument under space conditions by measuring temperatures in the middle atmosphere. The 3U CubeSat AtmoCube-1 is currently developed within the Development Initiative for Small Satellites Exploring Climate Processes by Tomography (DISSECT), initiated at the University of Wuppertal and the Research Centre Jülich. The AtmoHIT experiment consists of a highly miniaturized and rigid Spatial Heterodyne Spectrometer, which measures the oxygen atmospheric band emission in the middle atmosphere. The instrument resolves individual rotational lines whose intensities follow a Boltzmann law allowing for the derivation of temperature from the relative structure of these lines. This instrument is characterized by its high throughput at a small form factor, allowing to perform scientific remote sensing measurements within a CubeSat.
RX21 – SALACIA (Saline Liquids and Conductivity in the Atmosphere)
Luleå University of Technology, Sweden
Launch Date: 15 March 2017
The search for water has been one of the main focuses within the space and planetary exploration community for a long time. Data taken by the Mars Science Laboratory (MSL) has recently indicated that there is in fact an active water cycle on Mars. This water cycle is driven by a process where chlorate and perchlorate salts commonly found on the Martian surface absorb atmospheric water and transition into a liquid state, a brine. Due to its importance for the future exploration of our red neighbour, the ExoMars 2018 mission will include an instrument, HABIT, to further investigate the water cycle.
The SALACIA student experiment will provide an opportunity to study the properties of the Martian salts prior to the ExoMars 2018 launch. By flying a selection of these salts on a REXUS rocket, SALACIA will investigate their behaviour during the flight through different atmospheric layers. The main focus of the investigation will be on the absorption of water by the salts, and by camera recording how they react during the flight. Additionally, SALACIA will work as a pre-study for HABIT and as such, will help to identify and understand critical behaviours of the salts during a real-world rocket flight.
Student Experiment Documentation v5-0
BX22 – BuLMA 2015 (Balloon micro Lifeform-and-Meteorite Assembler)
Warsaw University of Technology, Poland
Launch Date: 5 October 2016
The BuLMA experiment is an advanced form of a particle-recuperating machine, belonging to Students’ Space Association of Warsaw University of Technology PARTICULA balloon experimental programme. The first PARTICULA experiments were based mostly on stratospheric sails of different sizes equipped with magnetic elements, which were flown under latex balloons to 30 km of altitude to collect iron (chondritic) spherules and additional particles. An alternative to sail-magnetic experiments, travelling in low velocities and having contact with a quite low total volume of air, is a stratospheric aerodynamic device based on multiple cyclone units equipped with fans able to collect not only micrometeorites and dust particles, but also so-called mesoxenes or microorganisms that originated from the Earth but no longer resemble Earth-like life forms . A mission duration of a few hours in the stratosphere and much greater total volume of used air should greatly increase the number of caught particles.
BX20 – COSPA (Collection Of Stratospheric aerosol PArticles for a better understanding of the development of Polar Stratospheric Clouds)
TU Darmstadt, Germany
Launch Date: 10 October 2015
While aiming to collect stratospheric particles, the COSPA team of TU Darmstadt is intending to apply a multi-MINI impactor device on a balloon of BEXUS 2015. The multi-MINI device contains 12 impactors with two stages each with cut offs of 500 and 10nm respectively. Particles on the coarse fraction will be collected on boron grids in order to be able to identify carbonaceous particles. Particles on the fine fraction will be collected on Transmission Electron Microscope (TEM) grids to make TEM analysis possible to display the particles of the smallest size range. The collected particles will be analyzed by SEM and TEM at TU Darmstadt. With these methods size, chemical composition and morphology of the particles can be identified. TEM even offers the possibility to get phase information of the particles. These informations are important to validate the particle quality in the polar stratosphere and also distinguish weather the particles are of natural or anthropogeneous origin. This is necessary, because those particles may act as condensation nuclei of Polar Stratospheric Clouds, which again have a huge contribution to the ozone depletion occurring in the Polar Regions.
BX21 – FREDE2015 (FREon Decay Experiment)
Wroclaw University of Technology, University of Wroclaw, Poland
Launch Date: 7 October 2015
The main goal of experiment is to study disintegration phenomenon of chlorofluorocarbons (CFC’s) – group of refrigerators commonly known as Freon’s (name reserved for DuPont). As radiatively active gases present in Troposphere and Stratosphere, they influence the depletion of the Earth’s ozone layer (O3) and the increase of the greenhouse effect. An experiment consist of test samples reservoir exposed to low and high altitude (<=25 km) conditions is design to collect information about CFC’s decay process, especially its chemical products due to dedicated on-board measurement chamber. Experiment will fly on board of stratospheric balloon lunched from Esrange (Kiruna, Sweden) by Eurolunch in September 2013. Carefully design system of sensors and measurement methodology will ensure that data collected for different levels of selected CFC’s concentration is reliable source of information about its disintegration process.
BX18 – A5-Unibo (Advanced Athmospheric Aerosol Acquisition and Analysis)
University of Bologna, Italy
Launch Date: 10 October 2014
A5-Unibo has the objective to study the physics involved in ion-induced nucleation by collecting data of the atmosphere that would help understanding the link between aerosol ionization and cloud formation. In order to do this the team will perform a series of in-situ measurements of the main parameters that are involved in this process: Temperature, Humidity, Pressure, Particle density, Ion density and radiation flux. Furthermore, as a secondary objective the team wants to measure the composition and relative abundance of aerosol particles by collecting samples through the use of filters and impactors mounted on an air pump. The aerosol will be collected in the Stratosphere, once reached nominal altitude and in the troposphere, during ascending phase. The samples will be recollected after the flight and analyzed in laboratory.
BX18 – TamaOS (Monitoring of ozone and oxygen concentrations with miniaturized solid state sensors)
TU Dresden, Germany
Launch Date: 8 October 2014
The primary technical objective is to evaluate performance of in-house developed miniature solid state ozone sensors in the upper atmosphere. Secondary technical objectives include comparisons with data from commercial sensors and from current REXUS payload “MOXA” to observe any variations in performance due to changing conditions. The scientific objective is to gain a complete picture of oxygen concentrations (O, O2 and O3) for the flight period, observe how they influence each other and shed light on possible mismatches between existing climatic models and reality, as well as establishing statistical correlation with measurements from the MOXA experiment.
RX15 – MEDUSA (Measurements of the D-region plasma using active falling plasma probes)
University of Rostock, Germany
Launch Date: 29 May 2014
The MEDUSA experiment, as a part of the REXUS/BEXUS project, develops a new in-situ technique probing the lower ionosphere plasma by two daughter payloads. These identical daughter payloads contain a sensitive structure that is exposed to the atmosphere. This structure consists of a grid, which surrounds an ion collector that is connected to a electrometer. The collector has a negative potential, the measured current at the electrometer is proportional to the ion density measurements. The positively charged grid shields the collector from ambient electrons. Acceleration sensors inside each payload can be used to derive neutral gas density profiles from the Navier-Stokes equation. These neutral density profiles can be used to investigate possible correlations with the plasma densities. From this density profile, assuming hydrostatic equilibrium one can integrate a temperature profile. A GPS receiver on each sub-payload provides in-situ horizontal information of all three physical quantities (ion, neutral density and temperature) that hasn’t been available in this scientific field before. During the REXUS 15/16 campaign a rocket will bring the two probes up to 90 km, which are then ejected from the main payload. In the following, the daughter payloads measure the ion density. The data is stored on the daughter payloads and is sent also to a ground station if a recovery of the probe is not possible. The scientific scope of MEDUSA is measuring small scale fluctuations in the plasma density of the D-region. Enabling investigations on the physics of the atmospheric phenomenon polar mesospheric winter echoes (PMWE), which are radar echoes in the range of 55-80 km. Possible occurrence of PMWE during the REXUS campaign is monitored by the ESRAD radar, which is located directly at Esrange Space Center. Furthermore the obtained plasma density height profiles can be compared with results from the Sodankylä Ion and Neutral Chemistry model (SIC-model). Doing that could give new insights into the ion chemistry in the D-region which is still not fully understood.
RX16 – MOXA (Measurement of Ozone and Oxygen in the Atmosphere)
TU Dresden, Germany
Launch Date: 28 May 2014
The models of the distribution of residual gases vary widely, for instance the atomic oxygen models deliver results which are up to 400% different. But to predict climate it is important to know about the distribution of Oxygen in its various forms, and for instance atomic oxygen is a major influence on space borne objects, resulting in degradation of exposed materials. Therefore the MOXA experiment will measure ozone, atomic and molecular oxygen, temperature and pressure during the flight. The Institute for Aerospace Engineering at TU Dresden have developed innovative sensors for oxygen and ozone with a very low response time and high measurement accuracy. The oxygen sensors of the experiment FIPEX already performed successful measurements onboard the International Space Station and will be integrated in the experiment in a new miniaturized form. The newly developed ozone sensor will be tested by comparing the measured data during the flight, in dependence of the pressure, with existing data. In addition the data of the oxygen measurements give a hint on the ozone values and will help to verify functionality of the ozone sensor. The development of precise sensors for residual gases contributes to the survey of the atmosphere to correlate existing atmospheric models or combine their area of validity and measured time resolved data to create a new model. So it is possible to make precise prediction of residual gases. This will support atmospheric science and improve the preparation of already planned long term missions in the LEO. The sensors are also applied in many other sections, for example breathing gas analysis.
RX13 – MUSCAT (MUltiple Spheres for Characterisation of Atmospheric Temperature)
KTH Royal Institute of Technology, Sweden
Launch Date: 9 May 2013
The objectives of the MUSCAT experiment are to measure atmospheric temperatures and horizontal winds in the mesosphere. Due to its remoteness, knowledge of the middle atmosphere is relatively limited, but the temperatures are required to establish their influence on the motions and dynamics of this region, their inter-relationship with the electrical structure and chemical species, as well as the morphology of occurring events. The measurements will be conducted using rigid spherical probes, which will be ejected from a rocket mounted unit. Each probe will contain sensors coupled with a GPS system, which will determine the speed and acceleration of the probes. This will allow the team to determine the induced drag on the probes, and the subsequent air density. From this data air temperature can then be calculated. The end result of the experiment will be the production of altitude profiles of temperature and wind velocity, at four horizontally separated locations.
RX11 – RAIN (Rocket deployed Atmospheric probes conducting Independent measurements in Northern Sweden)
KTH Royal Institute of Technology, Sweden
Launch Date: 16 November 2012
The scientific objective of RAIN is to develop a proof of concept of a technique to conduct high-resolution vertical multiple point measurements of middle atmospheric aerosols. An increasingly important topic in meteorological sciences has been the monitoring of aerosol particles in the middle atmosphere. Middle atmosphere aerosols play an important role in determining the chemical composition and radiation balances of the whole atmosphere. As of yet there have been no measurement techniques that can gather high resolution distribution profiles of these aerosols. Through the use of multiple measurement probes, each fitted with a selection of collection materials that are exposed to aerosol particles at varying altitudes, it is hoped that such a distribution can be collected. Resolution of horizontal structures at probe separations on the order of hundreds of meters is an additional novelty of the experiment. Scanning electron microscope post-flight analysis will be conducted to observe the particles collected.
BX15 – SolSpecTre (Measurement of Solar Spectrum)
Carl von Ossietzky University of Oldenburg, Germany
Launch Date: 25 September 2012
Transmission and absorption properties are two examples of optical characteristics of solids, fluids and gases. Laboratory measurements of optical components (mirrors, prisms, etc.) are proving to be carried out in the experimental implementation much easier than the analysis of transparent media in the environment, such as the determination of solar spectrum, which depends on the height. The detection of relative spectral changes in the particular layers of the atmosphere, resulting from various gas compositions and aerosols is the scientific goal of the experiment. To achieve a successful measurement a specially designed experimental setup, which is installed in the gondola of the high-altitude research balloon BEXUS has to be used. The detection of the spectrum will be done by using a 300nm – 950nm sensitive spectrometer. An upwardly facing convex mirror will collect light in a sufficiently large section of the sky. Due to the decreasing concentration of water, oxygen and other gases, a relative increase in the ultraviolet and near-infrared spectrum and molecule-specific absorption lines is expected.
BX12 – LITOS (Liebniz Institute Turbulence Observations in the Stratosphere)
University of Rostock, Germany
Launch Date: 25 September 2011
The LITOS experiment aims to measure small scale fluctuations in atmospheric wind and temperature, with a very high vertical resolution (<1mm). At present there is still no definitive model of atmospheric turbulence, due to its unpredictable nature and the technically challenging measurement methods. Past experiments opened questions on the horizontal structure of turbulence cells. To address these questions, quasi horizontal resolution using several sensors in a row will be achieved; a first for suchlike balloon-borne turbulence experiments. Wind measurements will be conducted using a constant temperature anemometer (CTA), which operates by measuring the cooling effect of the air flow on a thin (5 μm) wire held at a constant temperature. Temperature will be measured using a resistance thermometer in the form of a thin (1 μm) wire. In order to correct for spurious winds, the gondola attitude and relative wind direction will also be recorded. Data analysis will include the computation of turbulence parameters such as energy dissipation rates, the comparison between turbulence in wind and temperature, and an investigation of the horizontal distribution of turbulence.
BX10 – CASS-E (Cranfield Astrobiological Stratospheric Sampling Experiment)
Cranfield University, UK
Launch Date: 9 October/23 November 2010
CASS-E was a life detection experiment which aimed to sample and characterise microbial life within Earth’s stratosphere, a hostile environment with near vacuum conditions and extremely low temperatures. Microbes can be found in the most extreme environments on Earth, and their detection within the stratosphere could increase our understanding of possible paths for global microbial dispersion and could be used to test the hypothesis of Panspermia; the possibility of microbial transport through Space, seeding life on other planets. The experiment essentially consisted of a pump which drew air from the stratosphere through a 0.2 μm collection filter which retained any microbes and >0.2 μm particulates present in the pumped air. Due to the expected rarity of microbes in the stratosphere, and in order to be confident that the microbes detected are truly stratospheric, instrumentation was rigorously cleaned and sterilised using Planetary Protection and Contamination Control (PP&CC) methods. Bio-barrier technology was also used to prevent recontamination after sterilisation. It was anticipated that examination of the filters post-flight, would determine whether contamination has occurred from any of the areas contaminated with fluorescent beads. Staining (i.e., the use of a dye to study microbes) would also allow the detection of any collected microbes.
RX07 – MONDARO (Measurement Of Neutral gas Density in the Atmosphere by ROcket)
University of Rostock, Germany
Launch Date: 2 March 2010
The MONDARO experiment aimed to apply and establish a new and cost-effective means of conducting in-situ measurements of atmospheric densities and temperatures. This was to be achieved by using three Pirani-gauges, which is a standard gauge for neutral gas density measurements, and is normally used for pressure measurements in heating systems. The Pirani gauge can determine these atmospheric parameters with an accuracy of ~5% and an altitude resolution of ~50m. For the test flight, the Pirani gauges were mounted on the front deck of the REXUS nosecone; one exactly on the axis of symmetry of the rocket, whilst the other two Pirani sensors were mounted symmetrically off axis. The sensors were used to map the temperature and neutral gas density of the atmosphere between the altitude ranges of 50-100 km. This is a region of the polar mesosphere that is host to a number of fascinating geo-physical phenomena that are primarily caused by its extraordinary thermal structure. The analogue Pirani signal was then converted into a digital signal via an AD-converter and sent to the ground by down linking for analysis.
BX08 – MATI (Measurement of Atmospheric Turbulence with combined Instruments)
Leibniz-Institute of Atmospheric Physics, Univeristy of Rostock, Germany
Launch Date: 10 October 2009
The MATI experiment aimed to investigate and characterise the phenomenon of atmospheric turbulence by measuring the small scale fluctuations of wind and temperature, with high vertical resolution. Turbulence is one of the foremost topics of research in atmospheric physics, since a comprehensive phenomenological understanding has yet to be reached. Because turbulence is the random fluctuation of air mass at minuscule scales, it is difficult to measure and forecast in the atmosphere. MATI proposed to do just this by using three separate measurement methods. MATIwind contained a thin tungsten wire operating at a constant temperature which measured the cooling effect caused by atmospheric air flow over the wire, thus determining wind fluctuations. MATItemp also contained a thin tungsten wire that operated at a low constant current. The output, which represented resistance, varied linearly with the ambient temperature and allowed the identification of temperature fluctuations. MATIsound measured the speed of sound by emitting an acoustic sinusoidal signal, and receiving this signal via two microphones. The emitted signal underwent a phase shift, induced by atmospheric temperature changes. By detecting this phase shift temperature fluctuations were identified, without thermal inertia. This experiment represented the first time that three such methods were used in the same payload, and therefore provided a good means of comparison. The collected data was used to calculate typical turbulence parameters, so as to characterise the nature of small scale turbulence and was compared against simultaneously performed lidar and radar measurements.
RX05 – CharPa (Charge state of mesospheric smoke Particles)
IAP Kühlungsborn & TU München, Germany
Launch Date: 13 March 2009
The CharPa experiment was designed to analyse the charge state of mesospheric smoke particles (of meteoric origin), by means of in-situ measurements collected by a Faraday cup device. The Faraday cup is a cylindrical vessel with a collecting electrode placed behind two screening grids, which are biased (both positively and negatively) to reflect ambient plasma. The heavy meteoric smoke particles are not sensitive to this bias and penetrate inside the cup producing a small current on the electrode. To correctly interpret the data measured by such an instrument, one has to exclude an effect called triboelectric charging. This effect appears due to the transfer of electrons between materials with differing work functions (i.e. electrode and impacting dust particles). The CharPa experiment employed a Faraday cup with an electrode split into four separate parts: each made of a different material; each with varying working functions. The current produced by each electrode was measured separately to yield information regarding the charge state or working function of the dust particles material.
RX06 – NISSE (Nordic Ionospheric Sounding rocket Seeding Experiment)
University of Bergen, Norway, University of Oulu, Finland, Finnish Meteorological Institute
Launch Date: 12 March 2009
The main goal for NISSE was to evaluate how effectively the tri-static EISCAT UHF radar systems can be used in active rocket chemical release experiments. This was to be achieved by releasing ~8 kg of water into the ionosphere at an altitude of ~90 km, and by observing how well the artificial water is detected and measured by incoherent scatter radar in the UMLT region. It was anticipated that the water would flash boil upon release, and go through cycles of evaporation, condensation and sublimation. The water molecules that propagate as a result of these cycles are then ionised by solar radiation and high altitude ionic chemistry, modifying the ambient ion composition of the surrounding clouds. These changes cause local variations in the ionospheric plasma parameters, such as electron density, which can be measured along with the effect on the incoherent scatter spectrum by the EISCAT UHF radar systems. This data, along with raw UHF data collected by the experiment, was used to carry out post-experimental analysis using statistical inversion methods.
BX06 – TURA (TURbulence in the stratospheric temperature and wind fields)
Leibniz-Institute of Atmospheric Physics, University of Rostock, Germany
Launch Date: 8 October 2008
The scientific objective of the TURA experiment was to study small scale stratospheric turbulence and its effect on gravity waves, by combining two independent measurement techniques. Gravity waves and turbulence play a crucial role in understanding atmospheric energy and momentum transfers, as well as trace gas distribution. Knowledge of stratospheric turbulence is therefore very important to comprehend the propagation of gravity waves into the mesosphere, and to understand fundamental stratospheric processes. TURATEMP studied stratospheric turbulence by observing temperature fluctuations. The measurement principle was based on the proportionality between the speed of sound and the square root of the temperature. So by measuring the phase delay between transmitting and receiving an acoustic signal, the fast temperature fluctuations, and associated small scale turbulence could be determined. TURAWIND measured turbulent structures in the horizontal wind field along the BEXUS flight path, by observing the air-flow induced cooling of a heated wire. Changes in flow velocity caused voltage variations, thus providing further information on turbulence levels.
BX07 – DOLS (Diversity and Origin of Life in the Stratosphere)
various universities, Germany
Launch Date: 8 October 2008
The DOLS experiment aimed to gather information on the extent of micro-organism life in the stratosphere, by collecting atmospheric samples and classifying any found organisms via genetic analysis. A manifold of environments on Earth are host to living organisms. Even hostile environments such as the deep sea, eternal ice fields, in ground layers of rock and the Polar Regions support a surprisingly high bio-diversity of adapted organisms; mostly comprised of bacteria and archaea. Even more airborne species have been found in many places on Earth. There are several organisms that are claimed to be found in the stratosphere alone, which have been successfully cultivated but rarely sampled directly. The DOLS experiment therefore aimed to collect and filter samples directly from the stratosphere which would be frozen, to preserve the cells and their DNA, and returned to the ground for genetic analysis. Through a number of tests, any DNA found within the samples should be detected, from which bio-informatics analysis would follow. It was anticipated that this experiment would yield the fullest picture to date of the genetic biodiversity in the stratosphere.
BX07 – Stratospheric Census (Dust in the stratosphere)
‘Erasmus Mundus’ Space Masters Course
Launch Date: 8 October 2008
The Stratospheric Census was an experiment designed for the in-flight acquisition and post-flight analysis of stratospheric aerosols. The Earths stratosphere contains aerosols of various origins; including aerosols from volcanic, cosmic and anthropogenic sources. By analysing these aerosols, key information on stratospheric chemistry can be obtained, which in turn has an effect on the atmospheric radiation balance and World climate. The experiment collected aerosol samples through the use of a vacuum pump driven, permeable nano-filter, which traps particles as small as 0.3 μm in diameter. Two ground controlled valves were used, which could direct the flow through this filter or bypass it altogether, thereby allowing control over which sections of the atmosphere were sampled. Stratospheric Census sampled the atmosphere between the altitude ranges of 13.1-27 km. Upon recovery, the filter was analysed using various techniques such as Autoradiography, microscopic inspection, and Incident Neutron Activation Analysis, which were expected to yield further information on the composition of detected aerosols.
