Israeli Space Research
By Wendy Elliman
Israel officially entered the space age with the lift-off of its first satellite, Ofeq-1, from the locally built Shavit launch vehicle on September 19, 1988. With that launch, Israel joined an exclusive club of countries - Russia, the United States, England, Japan, India, France and China - that have developed, produced and launched their own satellites. Israel has since made important contributions in a number of areas including laser communication, research into embryo development and osteoporosis, monitoring pollution, and mapping geology, soil and vegetation in semi-arid environments.
The next step is being taken in early 2003 when NASA launches the 28th flight of space shuttle Columbia, on mission STS-107. The seven crewmembers on board include the first Israeli astronaut, Ilan Ramon.
The 16-day mission of Ramon and his colleagues is devoted to research, with over 80 experiments in earth and space sciences, human physiology, fire suppression, and the effect of microgravity on a wide variety of natural phenomena. A colonel in the Israel Air Force with more than 4,000 flight hours accumulated over his 20-year career, Ramon is the only payload specialist on the mission. He is the prime crewmember for the Mediterranean Israeli Dust Experiment (MEIDEX) studying the transport of mineral (desert) dust in the atmosphere over the Mediterranean Sea and the tropical Atlantic Ocean, which plays an important role in weather and climate conditions in the region. Ramon is also investigating sprites, rare forms of lightning that occur above thunderstorms at heights of up to 90 kilometers.
Together with universities, commercial companies and other government agencies, young students from around the world are also participating in the experiments. Among them are schoolchildren from the Ort-Matzkin School in Haifa, who are investigating the growth mechanisms of crystalline fibers in the absence of gravity.
The 1988 launch of Ofeq-1 was coordinated by the Israel Space Agency (ISA), established five years earlier to support and coordinate private and academic space-related research into areas such as electronics, computers, electro-optics and imaging techniques, which had already been in progress for some 20 years under the management of the National Committee for Space Research.
Designed as a technological satellite, Ofeq-1 spurred Israel's capability to send a satellite into orbit. Both Ofeq-1 and its successor, Ofeq-2, launched in April 1990, were very successful, sending back a stream of vital technical information. The two satellites reentered the Earth's atmosphere within six months of their launching.
Ofeq-3 was launched in 1995 with an advanced electro-optical payload. It more than doubled its expected lifespan, downloading images of superior quality. The unbroken success of Israel's satellite program was, however, brought to an abrupt halt with Ofeq-4. This fourth satellite in the series encountered problems in the second stage of its January 1998 launch. It burned up, setting back Israel's satellite reconnaissance program by several years.
The latest satellite in the series, Ofeq-5, was launched by a Shavit launcher in May 2002. Circling the Earth every hour and a half, Ofeq-5 is a reconnaissance satellite capable of delivering color images with an extraordinarily high resolution of less than a meter. The projected lifetime of Ofeq-5 is approximately four years. Meanwhile, IAI is currently developing the next satellite in the series, Ofeq-6, with an advanced payload capable of all-weather operation.
In addition to Ofeq-5, photo images are currently being trans-mitted by EROS-A (the Earth Remote Observation System), a commercial satellite made by Israel Aircraft Indus-tries (IAI) and launched from Siberia on December 5, 2000. The EROS-B satellite, currently under development, is due to be launched in the first half of 2004.
Underlying the success of the Ofeq satellites and their comparatively inexpensive launch capability are Israeli developments in the field of miniaturization. Lighter satellites are more efficient and save hundreds of thousands of dollars per launch.
Israel launched a micro-satellite into orbit in June 1998. Developed at the Technion - Israel Institute of Technology in Haifa for a mere $3.5 million, TechSat II is a marvel of miniaturization. The satellite is an 18-inch cube that weighs just 106 lbs. It orbits 516 miles above the earth, generating its own energy from the sun, and is packed with miniature cameras, computers and other locally manufactured space hardware used in communications technology, remote sensing, astronomy and geoscience.
TechSat II comes within photographing distance of Earth a dozen times a day. The ground-monitoring station at the Technion's Asher Space Research Institute downloads regular measurements of the atmosphere's ozone content from its ultraviolet sensors. From its charged-particle detector, scientists gauge the frequency with which such particles impact on the satellite and the potential damage they could cause to sensitive equipment such as computers. They also study the photographs recorded by its tiny camera.
Begun in the 1980s as a student project, TechSat rapidly extended its boundaries into a professional satellite program. With the arrival of immigrant scientists from the former Soviet Union, the project took on its current form, making the Technion one of the few universities worldwide to have designed, built and launched a satellite.
Currently, satellites positioned high above the Earth communicate with each other via radio wave signals, which bounce from one to the other. But according to Natan Kopeika, head of the Masters Degree Program in Electro-Optics at Ben-Gurion University of the Negev, lasers will soon significantly upgrade communication between them.
"Lasers use less power, they are lighter and smaller, and can be more easily directed into a narrow beam-width," Kopeika explains. "Together with the Technion's Asher Institute, we are developing techniques for pointing, acquiring and tracking techniques that will aim laser beams accurately between satellites."
Kopeika foresees a network of such satellites, allowing communications (telephone, internet, e-mail, cable TV) to be up-linked from Earth to a first satellite, forwarded to the next and so on, until they are down-linked back to Earth perhaps halfway across the globe.
Research in Space
As well as developing space hardware, Israel is using space as a platform to find out more about life on our own planet. In October 1996, ISA and NASA signed an active umbrella cooperation agreement, which allows Israeli life sciences experiments to be integrated into NASA space flights. The experiments conducted in the last five years have led to greater understanding in the fields of embryogenesis (the early development of mammals), osteoporosis (loss of bone density) and the setting up of 'space farms' in order to supply spaceships and space stations of the future with food.
In February 2000, scientists from Ben-Gurion University of the Negev (BGU) took a "virtual" ride on a NASA space shuttle - the Endeavour. Among the shuttle's tasks was an accurate topographical mapping of the earth's surface. Precise knowledge of height variations in deserts may help track their expansion, as well as the movement of sand dunes, both of which are essential for understanding and preserving the ecology of arid and semi-arid regions. Most deserts have never been accurately mapped due to a lack of interest in unpopulated regions, and the difficulties involved in using "radar interferometery" (a mapping technique which uses radar energy backscattered from the surface): in desert regions the radar signals can penetrate several centimeters into the sand providing unreliable results.
To solve the radar-signal problem, a team of scientists at the earth and Planetary Image Facility (EPIF) at BGU's Depart-ment of Geography and Environmental Development designed and positioned 13 specially constructed aluminum radar-corner reflector screen devices across the Negev. These provided the Endeavour with calibration points for accurate mapping during its five scheduled passes over the region.
Images of land seen from space are also helping scientists monitor land, water and vegetation on Earth. Satellite images of pasture and crop productivity in Kazakhstan and drought in the central USA have both recently been mapped and interpreted, using a system developed at BGU.
Data from satellites is received in custom-built receiving stations at BGU's Sde Boker and Be'er Sheva campuses. The information is calibrated, allowing the measurement of data such as chlorophyll concentrations in vegetation and pollutant distribution in water. Accurately estimating the pollution or degradation of the atmosphere, water and land is an important tool in the conservation of the planet. Research in this area is also being conducted at the Universities of Tel Aviv and Bar-Ilan, as well as the Hebrew University in Jerusalem. In addition, sea-surface ecology in the Mediterranean, along with its wind-fields, air-sea interaction, surface saline concentrations and recent oil-spills in the region are being measured by a remote sensing satellite.
Other related projects currently being developed in Israel include:
Space vehicles are about to receive a very large (and quite literal) boost from Israeli research, according to scientists at Ben-Gurion University. They have shown that a new type of nuclear fuel could cut the travel time from Earth to Mars from 10 months to only two weeks.
"It has long been known that the less the nuclear reactor which powers a space vehicle weighs, the more efficient space travel is," says Prof. Yigal Ronen, of the university's Department of Nuclear Engineering. To meet the challenge of a light nuclear reactor, Ronen examined one element of reactor design - the fuel. The study focused on the nuclear fission fuel americium-242m, which requires only one percent of the mass of uranium or plutonium to reach its critical state. It was found that this fuel could sustain fission in the form of extremely thin films of these elements, less than a thousandth of a millimeter thick. In this form, the exceedingly high-energy, high-temperature fission products can escape the fuel elements and be used for propulsion in space - either by heating a gas for propulsion, or by fueling a special generator that produces electricity.
There are still many hurdles to overcome before americium-242m can be used in space - examining reactor design, refueling, heat removal and safety provisions for manned vehicles - as well as the high cost of its manufacture. Americium-242m is already available in small quantities, and Ronen believes that the fuel will eventually be used for space travel.
Many international space programs have taken an interest in Israel's space achievements. In addition to NASA, Israel has formal space research cooperation agreements with France, Germany, Russia, the Ukraine and the Netherlands. Israel recently signed a similar agreement with India, which provides for the installation of an Israeli-produced telescope on an Indian satellite due to be launched in the next two years.
Israel sent its first geostationary telecommunications satellite into orbit on May 16, 1996. The Afro-Mediterranean Orbital System (AMOS) was built by Israel Aircraft Industries in partnership with Alcatel Espace of France and Daimler-Benz Aerospace of Germany. Launched by the French-built Ariane-4 launch vehicle, the AMOS communications satellite continues to provide high quality broadcasting and communication services for the growing markets of Eastern Europe and the Middle East. Due to its technological and economic success, IAI is due to launch an upgraded AMOS-2 satellite in early 2003.
The TAUVEX (Tel Aviv University Ultra-Violet Explorer) is one of several major multi-national space research projects in which Israel is an important player. A cluster of three ultra-violet telescopes, the TAUVEX will operate in a Russian space observatory together with instruments developed in Russia, Denmark, France, Germany, Italy, Switzerland, the United Kingdom and the United States. It is designed to image astronomical objects in the ultraviolet range, including different types of hot stars (such as white dwarfs and mixed-type binaries), and young massive stars, which emit large amounts of ultraviolet radiation and ionize the interstellar medium and are thus important in star formation and the evolution of galaxies. TAUVEX'S innovations include reducing sky background, a longer observing time per target and duration of service (up to five years). High on the list of tasks set for the TAUVEX is a survey of Local Group galaxies and nearby clusters of galaxies, which were not possible to observe through the Hubble Space Telescope because of its narrow field of view.
A spin-off of TAUVEX is a small telescope with a resolution of five meters that will be used on the DAVID, a small commercial remote sensing satellite. Developed jointly by an Israeli hi-tech company and a German firm, the project is supported by the E.U. and ISA.
Other joint projects include:
Source: Israeli Foreign Ministry