A first-of-its-kind Israeli satellite will be launched next week on a unique ecological mission, proving the efficacy of Israeli space technologies

A first-of-its-kind satellite is about to perform an unprecedented study, following the effect of climate change on different environments, using Israeli technology. The first Israeli satellite for environmental studies, Venμs, built as part of a collaboration between the Israeli and French space agencies, is equipped with an extremely advanced camera. It will image the same areas from the same angle over a long period of time, allowing the researchers to follow changes in vegetation, precipitation, state of the soil, pollution of water resources and more.  

Colors of change

Venus is the Roman mythology equivalent of the Greek Aphrodite, goddess of beauty, love, and procreation. In earlier versions of Roman mythology, she was the goddess of gardens, vineyards, and orchards. Thus it was only befitting to name a satellite on an ecological and agricultural mission after her. Officially, Venμs is an acronym for Vegetation and Environment monitoring on a New Micro Satellite, with the letter M replaced by the Greek letter μ, which signifies “micro” in scientific formulas.

The central instrument of the satellite is a hyperspectral camera – a multicolored camera made by Elbit’s Elop. It is comprised of twelve detectors, each imaging a different wavelength, that is, a different color, including wavelengths outside of the visible spectrum of light. Accurate image analysis using computerized algorithms will allow rapid detection of changes vegetation, soil, or water color, which will in turn lead to very early-stage identification of such processes as drying out of vegetation, cold damage, fertilizer shortage, soil oxidation, water pollution, and more. This accurate analysis will allow real-time intervention, and prevention of further damage. For instance, irrigation and fertilization amount can be customized to the state of the vegetation, pesticide can be applied before an outbreak occurs, and pollution can be identified and controlled before leading to extensive damage.

Imaging at different wavelengths also enables researchers to eliminate from the image clouds and other atmospheric interferences, thus acquiring a clear image of the Earth’s surface under almost any weather condition.  

For efficient tracking, the satellite will image the exact same area every other day. It will complete 29 orbits around the Earth every 48 hours, and on the 30th orbit, it will duplicate the first one. The imaging will take place at the same time and angle, with every image covering an area of 760 km2. The images will be transmitted to a ground station in Lapland in northern Sweden, and from there, to a laboratory in France for analysis. Subsequently, the laboratory will send the information to research facilities in Europe, America, Asia, and Africa.

The images of locations in Israel will be sent to the research center at the Sde Boker Campus of Ben-Gurion University, headed by Prof. Arnon Karnieli. The areas that will be imaged in Israel include most of the agricultural land in the country, as well as nature reserves, national parks, and natural forest regions.

A sophisticated motor

In order to maintain the constant orbit with high accuracy, the satellite is equipped with an innovative propulsion system, made by Rafael Advanced Defense Systems. The system includes two electrical motors that, using a magnetic field, turn xenon into plasma, which is a state of matter in which the electrons leave their atoms. The emission of the plasma generates greater thrust than a regular chemical motor, so that the satellite can perform the same maneuvers using less fuel, or perform more maneuvers and track corrections using the same amount of fuel. The electricity for producing the plasma will be generated using solar panels, which the satellite will deploy as it enters into its orbit.

The satellite will orbit the Earth at a height of 720 km, and after two years, will gradually descend into a lower orbit, of about 410 km. During both orbits, it will have to correct its direction and angle every once in a while, due to changes in the gravitational field, solar wind, or drag force generated by atmospheric particles. This will be done by an autonomous track control system, which is independent of the instructions and calculations of the operators in the ground control station. Successful function of the novel satellite motor and the track control system may open new markets for using these technologies.

29 הקפות כל יומיים, בגובה 720 ק"מ. ההכנות לשיגור הלוויין על גבי טיל "וגה" באתר השיגור | צילום: התעשייה האווירית
​​29 orbits every two days, at a height of 720 km. Preparations for the satellite launch on site, using the Vega rocket. | Photograph: Israel Aerospace Industries

En route to space

The satellite is 1.70 m tall and 1.20 m wide. With the solar panels spread out, its total width will reach 4.20 m. It weighs 265 kg, including fuel. Despite these impressive dimensions, it is considered a “micro-satellite,” dwarfed by communication and other types of satellites.

The satellite will be launched on top of a Vega rocket from the European Space Agency’s launch site in French Guiana, South America. The 30 m-tall rocket will also be carrying an Italian observation satellite, also manufactured by Israel Aerospace Industries. The launch is scheduled for 10:58 pm (local time), August 1 (In Israel: Wednesday, August 2, at 4:58 am). 42 minutes after the launch, the rocket is set to release the Italian satellite into orbit, and 55 minutes later, it will release Venμs. At 10:30 am (Israel time), the first transmission from the satellite should be received in Israel.

During its mission, the satellite is planned to consistently image 110 sites all over the world, which were all chosen for specific experiments out of hundreds of requests that were submitted to the French Space Agency. The data received from the satellite will be utilized to study the impact of global warming, greenhouse gas emission, afforestation, agriculture, and more. In Israel, this project also has educational value, as the data collected will be analyzed as part of high-school projects of students in Rishon LeZion and Rehovot, with the financial support of the Israel Space Agency.

The Ministry of Science’s Israel Space Agency invested millions of shekels in developing the satellite and in the research stemming from the data it collects. In Israel, there is great hope that the investment will be fruitful, not just in generating useful ecological research, but also as a demonstration of the abilities of the civilian Israeli space industry. The success of the mission may serve as an advertisement for the Israeli companies involved in the manufacture and development of the satellite, resulting in a flow of millions of dollars to Israel through the signing of additional contracts of satellite and space system manufacture and development. 

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