Campaign information BEXUS 4 (2006)

BEXUS is a yearly recurring experimental flight with a stratospheric balloon that university students at Kiruna Space and Environment Campus carry out together with pupils from Hjalmar Lundboms School and the Space High School, Rymdgymnasiet. The objective of offering students this opportunity is to strengthen the cooperation between the different space educations running in Kiruna and to give the students inspiration and experience by participating in an real space related projects.

The Esrange E-Link system for communication between the gondola and the ground station at Esrange will be included in the flight and the aim is to perform a test flight and qualify the E-Link no 2 unit for operational use.

The balloon campaign will be carried out in cooperation with a supervisor from Esrange and the launch and flight safety will be made by the Esrange launch crew. The campaign is carried out under the provisions laid down in the Esrange/Andöya Special Project agreement (EASP). Sweden is the main user.



The BEXUS gondola suspended under the launch vehicle Hercules


The BEXUS gondola in a closeup picture.


Some of the experiments

The purpose of this project is measuring ozone in the atmosphere with the help of an ozone sensor from Vaisala.

The receiving station interprets the signal from the radiosonde on the ozone sensor and gives as output raw data of ozone measurments and other important parameters as temperature, pressure, air moisture and position. This raw data is then processed with the help of MATLAB and the result is compared with the data from the manufacturer of the sensor.
The main emphasis of the project is the data treatment and analysis.

The purpose of this project is to take high resolution photos and video recordings during flight. MMSP consists of a digital camera with 8MPixels and 4Gb flash memory mounted on a structure that can be turned in different directions. Everything is controlled by a micro controller that runs a preprogrammed routine but also can receive special commands during flight to be able to concentrate the view on different interesting flight events. In total there will be about 110 minutes of video and about 500 high resolution photos.

Altitude Determination by Image Analysis
The most important goal is to be able to point the camera at the horizon by image analysis (i.e. to find the horizon in the image). And then center this feature in the consecutive images by operating simple servos on the platform. The images will be stored onboard and also linked down to the ground station, where the images can be represented in realtime. Where this application may be useful is for instance exactly what the name says; altitude determination by image analysis, but there are more fields of application for this kind of equipment. Another example; if the curvature of the horizon is measurable by image analysis one can, by already knowing the altitude (from other sources), calculate the radius of the Earth.

Test of solar panels

Sampling of Air During Float and AsCEnt
In this experiment, a system will be created which can sample air on high altitudes. The experiment can be customized for future customers that want to sample particles on high altitude, for example carrying an organic filter or carry a container to store particles for future use.

Is a small EIS (Embedded Internet Systems) platform based on an Mitsubishi M16C microprocessor. The bare die microprocessor chip is mounted and bonded to the six-layer circuit board. The processor chip is covered with a glob top. All other components are surface mounted. On the same circuit board, mounted on the rear, is a Bluetooth module. The platform is battery powered and designed for low-power consumption. The size of the MULLE platform is only 25 x 23 x 5 mm.

Balloon Tracking Device
The goal of this project is to design a device which tracks the path of Bexus 4, by receiving a signal transmitted from the balloon at 173.225 MHz. The signal is received via a Yagi antenna, then filtered and amplified before it’s demodulated in a receiver located at the ground station. The controller unit extracts the position of the balloon from the demodulated signal and adjusts the position of the antenna to assure that it’s reception is optimal. The controller unit logs data to a computer so that the path of the balloon can be plotted afterwards.

Hjampis 1
Plants in space

Hjampis 2
Measurements of light and humidity

Read more about the students work at the student's Bexus 4 page

Read more about university space education at Department of Space Science

Contact persons:
Mr. Ola Widell, SSC project manager, Esrange Space Center
Mr. Mikael Koivunen, student payload manager, Department of Space Science
Mr. Johannes Reldin, subproject manager for experiments for university students, Department of Space Science