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Early Israel's Space Program

Shavit and Ofeq

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Ofek-16 (Ofeq-16),
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Early Israel's Space Program

Mike Gruntman's posting on Facebook on May 29, 2017

Israel's space program 35 years ago

After the Yom Kippur War of 1973 prominent Israeli nuclear physicist Yuval Ne'eman (1925-2006) returned to government service as a senior advisor in the Ministry of Defense. He began to argue for achieving reconnaissance satellite capabilities to correct, in his words, "astonishing" deficiency in photoreconnaissance. Yitzhak Rabin and Shimon Peres, who became the prime minister and minister of defense, respectively, in 1974, did not support the idea. After some time Ne'eman had to resign from his position, following disagreements with his superiors.

Menachem Begin served as the prime minister of Israel from 1977-1983. He succeeded in convincing Ne'eman to join his cabinet in 1982. On Ne'eman's insistence, Begin established the new ministry of science and agreed to create the space program in Israel for national security purposes. Ne'eman became the first minister of science and spearheaded organizing the new space activity with the decisive and indispensable support of Prime Minister Begin. Government activated the civilian Israel Space Agency in January 1983.

Five years later, Israel launched its first artificial satellite of the Earth Ofeq-1 on September 19, 1988. Rabin served at that time as the minister of defense. He did not want, in political payback, to let Ne'eman to observe this historic launch at Palmachim Air Force Base. So, Ne'eman watched the launch from the Soreq nuclear center not far away.

Today, Israel builds and operates satellites for national security, communications, and science.

Excerpts from Mike Gruntman's award-winning

Blazing the Trail. The Early History of Spacecraft and Rocketry, 2004, pp. 451-454

Early Israel's Space Program

Development of ballistic missiles was essential for survival of Israel as a country surrounded by hostile Arab neighbors intent on physical annihilation of the Jewish state. The achieved national ballistic missile capabilities subsequently enabled space launches. Naturally, the major objectives of the space program were also driven by the national security requirements and concentrated on spacebased reconnaissance and communications. The country's space effort received important boost in 1982 with the formation of the Israel Space Agency (ISA). Physicist Yuval Ne'eman, 1925–2006, played a crucial role in shaping the Israel's program ...

Israel's first step into space was a launch of a simple Ofeq-1 (ofeq means horizon in Hebrew) satellite on 19 September 1988, with the Israel Aircraft Industries (IAI) leading the effort as the prime contractor. The spacecraft was designed and built by IAI's MBT Division, and the satellite control center was established at MBT's facility in Yahud near Tel Aviv. The spin-stabilized (at 60 rpm) Ofeq-1 was deployed in a low-Earth orbit with perigee 248 km (154 miles) and apogee 1150 km (715 miles). Low orbit perigee resulted in large atmospheric drag, and the satellite reentered the atmosphere in four months on 14 January 1989.

The Ofeq-1 spacecraft was an octagon with the lower- and upper-base diameters 1.3 m (4.3 ft) and 0.7 m (2.3 ft), respectively, and height 2.3 m (7.5 ft). The spacecraft total mass was 156 kg (344 lb), with the mass breakdown among the subsystems, as follows: 33 kg (73 lb) for structures, 58 kg (128 lb) for electric power, 5 kg (11 lb) for thermal control, 12 kg (26 lb) for communications, 7 kg (15 lb) for onboard computer, 32 kg (71 lb) for spacecraft instrumentation and balancing masses, and 9 kg (20 lb) for cabling. The body-mounted solar panels supported average power consumption of 53 W, and the onboard battery had capacity 7 A-h. The S-band communications system provided a 2.5-kbit/s transmission rate.

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Space launch is especially challenging for Israel because political constraints limit possible launch azimuth to western directions against the Earth's rotation. Therefore, Ofeq-1 (as well as the follow on satellites) was placed in retrograde orbit with inclination 143 deg (or 37 deg retrograde). The IAI's MLM Division built a capable Shavit (comet in Hebrew) three-stage solid-propellant launcher to deploy satellites under such adverse restrictions. The solid motors of the first two stages were built by Israel Military Industries; the third-stage motor was designed by Rafael.

PROGRADE AND RETROGRADE ORBITS

Typically, spacecraft are launched in the eastern direction (from left to right, if one looks at the map). Therefore, most satellites move around the Earth in the same general direction as the Earth rotates. Such orbits are called prograde. The rotation of our planet is not negligible and provides significant help for launching satellites. The velocity of a point on the Earth's surface is approximately equal to 465×cos(lambda) m/s, where lambda is geographical latitude of the launching site. Thus, one gets "for free" a significant velocity (465 m/s at the equator) when launching a satellite due east.

Possible launch directions are usually restricted by safety considerations, to prevent first rocket stages, or malfunctioning rocket, from falling on populated areas. In Israel's case, political considerations do not allow space launches in the eastern direction. Therefore, the country has to launch satellites over the Mediterranean sea in the western direction, against the Earth's rotation. Such orbits are called retrograde. Launch in low-inclination retrograde orbits is highly unfavorable and requires significantly larger rockets than for similar eastward launches.

Shavit launched the Israel's first satellite from the Palmachim Air Force Base in Yavne, 15 miles (25 km) from Tel Aviv. Israel is a small country, and this is the only place in the world where satellites are launched from a site so near to a major metropolitan area. The Shavit's second stage cut off at approximately 110 km (68 miles) altitude. After coasting, the third stage was fired at 250–260 km (160 miles) injecting the spacecraft into the desired orbit. The shroud was jettisoned just before firing of the third stage.

With the launch of Ofeq-1, Israel also became a member of the small elite group of nations with space launch capabilities ...

... [snip] ...

Blazing the Trail. The Early History of Spacecraft and Rocketry, Chapter 17, pp. 451-454, 2004

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