Tuesday, February 3, 2009

Iran launches first homegrown satellite

The Iranian government has again demonstrated its capacity to deliver a payload into earth orbit, launching it's first "home grown" satellite, the small Omid communications payload Mesbah. Policy makers have long known the capacity to launch a payload into Earth orbit, in theory, demonstrates the capacity to place a warhead anywhere on the surface of the Earth. The launch into a highly-inclined orbit from a relatively high lattitude is also a demonstration of a powerful booster, in this case the Safir 2.

According to Stephen Clark at SPACEFLIGHTNOW.COM, the small payload is in a highly inclined orbit, relative to the equator, only 2 degrees out of phase with the inclination of the orbital plain occupied by the International Space Station, though Mesbah's orbit is of greater eccentricity, with apogee of 378 to 439 kilometers (235 to 273 miles) and perigee of roughly 246 kilometers (153 miles).

Though this orbit is more highly elliptical, a longer semimajor axis demonstrates the, perhaps unintended, capacity to allow vehicles in lower orbits of less eccentricity to catch up with the Iranian payload. Though Iran calls Mesbah a communications satellite, the minimal size and low orbit of high orbital inclination relative to the equator allows communication windows to open over any single point on 80 percent of the surface of Earth only three or four times daily, in a set of opportunities bunched together in roughly 90 to 100 minute intervals. This hardly the optimal orbit for fast point to point communications, as any long-term veteran of the ISS will testify.

Read the GlobalSecurity.org summary of Iranian Safir launch capacity HERE.

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