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Focus on Israel: Israel in Space |
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Israel in Space
January 2003
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by Wendy Elliman |
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First Israeli astronaut, Col. Ilan Ramon
Courtesy NASA
Crewmembers of space shuttle mission STS-107, with Ilan Ramon (right)
Courtesy NASA
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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 was taken in early 2003 when NASA launched the 28th flight of space shuttle Columbia, on mission STS-107. The seven crewmembers on board included the first Israeli astronaut, Ilan Ramon.
| On February 1, 2003, the astronauts of mission STS-107 were killed when the space shuttle Columbia disintegrated upon re-entry into the Earth's atmosphere.
Israel deeply mourns the loss of Colonel Ilan Ramon and his six colleagues - shuttle Commander Rick Husband, Pilot William McCool, and Mission Specialists Michael Anderson, laurel Clark, David Brown and Kalpana Chawla - and shares a profound sense of grief with the astronauts' families and the American people.
Despite this terrible tragedy, Israel intends to continue to cooperate with NASA to move the space program forward and explore new boundaries of science, as inspired by the seven astronauts. |
The 16-day mission of Ramon and his colleagues was 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 was the only payload specialist on the mission. He was 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 also investigated 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 also participated in the experiments, among them schoolchildren from the Ort-Matzkin School in Haifa, who are investigating the growth mechanisms of crystalline fibers in the absence of gravity.
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Ofeq-5 satellite
Courtesy ISA
Shavit launch vehicle
Courtesy ISA
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New Horizons 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 transmitted 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.
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TechSat II satellite
Courtesy American Technion Society
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Mini-technology 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.
Laser signals 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.
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Professor Dan Blumberg, Director of the Earth and Planetary Images Facility (EPIF) at Ben-Gurion University, inspects one of the aluminium radar-corner reflector screen devices in the Negev Courtesy Dani Machlis/BGU |
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Topographical mapping 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.
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Satellite image (combining infra-red and red light) of the Eastern Mediterranean, recieved by the Multi-mission Earth Observation System operating in the Department of Geography and Environmental Development, BGU
Courtesy EPIF, BGU
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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:
- Automatic generation of digital elevation models (DEM) using Spot and Landsat imagery
- Mapping of geology, geomorphology and associated seismic activities in the Jordan Rift Valley
- National database for digital satellite images
- Remote sensing study of vegetation cover as indicators of soil condition, for example using the colors in cotton fields as an in-dicator of the levels of soil salination
- Remote sensing of the impact of cloud-aerosol interaction on precipitation processes and amounts of rainfall
- Subsurface remote sensing
- Remote sensing monitoring of water quality in Lake Kinneret (Sea of Galilee) and the Mediterranean Sea
- Geomorphology of Mars and Venus
Nuclear fuel 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.
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International cooperation 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.
In June 2003, Israel was accepted into the European Space Agency (ESA) as a participating member. The agreement will allow Israel to participate in European space projects and to submit proposals for joint development projects.
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.
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TAUVEX -
Ultra Violet Astronomical Telescope
Courtesy ISA
David Muti Spectral System
Courtesy ISA
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The TAUVEX (Tel Aviv University Ultra-Violet Explorer) scientific instrument constructed by El-Op (Electro Optical Industries, Ltd.) is one cornerstone of a major international space research project in which Israel is an important player. The three-telescope array 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 processes and in the evolution of galaxies. TAUVEX operates in a spectral region with reduced sky background, thus can detect relatively faint objects with a modest observing time per target. TAUVEX is slated to fly on the Indian satellite GSAT-4 as part of the India-Israel Agreement on Space Exploration. Its multi-year mission will yield a very deep survey of part of the sky; this will enhance considerably our knowledge about evolution in the universe.
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:
SLOSHAT, conducted with the Dutch Space Agency. As its expressive name suggests, the project examines the phenomenon of 'sloshing' in the larger fuel tanks of satellites. Scheduled for launching from a NASA space shuttle in the near future, it will be equipped with an Israeli thruster system.
ISA, in cooperation with NASA and the French Space Agency (CNES) is also funding a small laboratory at the Israeli Nuclear Research Center, which inspects every component of a shuttle before launch, to ensure it will be able to survive the hostile space environment.
A Ground Receiving Station for satellite images was established by ISA on the grounds of the Israel Aircraft Industries, where images of the French Spot satellite and the European Radar Satellite (ERS) are routinely received.
Israel will participate in the European Global Navigation Overlay System (EGNOS), as well as the new Galileo project.
A joint project sponsored by ISA and the Survey of Israel is working on the establishment of a Global Positioning System (GPS) infrastructure in Israel for geodetic and geophysical applications.
An agreement has been signed between ISA-NASA and the Israel Meteorological Service, together with the scientific cooperation of the Hebrew University of Jerusalem, to establish a ground validation site in Israel for the Tropical Rainfall Measuring Mission (TRMM). The first mission dedicated to measuring tropical and subtropical rainfall, the TRMM will help improve weather forecasts, predict wind patterns and ocean currents, floods and droughts.
In 1999, ISA and NASA established in Israel the Middle East Interactive Data Archive (ISA-MEIDA) in order to create and maintain an Earth observing data center available through the internet to the research community and to the general public. It is one of the international data centers participating in NASA's Earth Observing Israeli investigators are also attracting notice for new theories in the realm of pure science - theories that may one day contribute to the exploration of space. A long-held hypothesis about unseen and unmeasured 'dark matter' in the universe that holds together galaxies is being challenged by Prof. Israel Dostrovski of the Weizmann Institute of Science in Rehovot. Dostrovski proposes that if Newton's law of gravitation is slightly adjusted, the behavior of star clusters and galaxies makes perfect sense. New astronomical data have begun corroborating this theory.
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