Friday, February 1, 2013

CNN Announces Iran Puts Monkey in Orbit! (Not)

I heard it clearly: CNN announced that Iran had put a monkey in orbit.  Several news sources also mentioned that the United States could not confirm the story.  So what’s the truth?

The truth is that CNN apparently was hoodwinked by an astonishingly misleading press release from the Iranian press agency, which used the word “satellite” to describe a mere probe.  The Iranian launch was on a Kavoshgar 3 ballistic missile capable of attaining 100 km altitude but far too slow to achieve orbital velocity.  The monkey flew a parabolic trajectory that reached 120 km altitude, but certainly did not circle the Earth.  American radar and optical tracking stations regularly monitor all satellite traffic, and infrared-sensing military surveillance platforms in geosynchronous orbit high above the equator keep an eye on all rocket launches.  But neither of these tracking systems is equipped with a monkey detector.  Anything that gives off lots of heat is fair game: bored staff members at USAF Space Command used to pass the time by checking whether the trains on the Trans-Siberian Railroad were keeping to their schedules.  But a train gives off far more heat than a monkey.

So why is 100 km altitude considered “space”?  The answer is quite simple: 100 km is the lowest altitude at which a typical satellite can survive for a single orbit against the retarding forces of air friction.  Satellites with unusually large area (such as a large expanse of solar cells) and low mass experience more drag deceleration, and would not last for even one orbit at this altitude before reentering the atmosphere and burning up.  Compact, dense satellites (such as those launched to study Earth’s gravitational field) would last a little longer.  But for typical satellite designs, surviving one orbit (about 87 minutes) at 100 km would be about normal.  Besides, 100 is such a nice, round number.

And what does “in orbit” mean?  It means that the object is following a ballistic (un-propelled) path that will take it all the way around a body such as Earth or the Sun.  For orbits around Earth, that means at least a 40,000 km trip.  The Iranian monkey launch traveled about 200 km, not 40,000, and briefly reached a maximum altitude of 120 km.

Not that Iran can’t launch small satellites: it has already done so three times, in 2009, 2011 and 2012.  A real orbital mission with a monkey aboard is a possibility for the future.  The remarkably uninformative press release by the Iranian press agency tells nothing about the launch, but does mention that the purpose of this flight is to prepare for manned spaceflight—and adds that the launch was in celebration of Mohammed’s birthday.  The Director of the Iran Space Agency, Hamid Fazeli, recently announced that Iran plans to send humans on “half-hour” space flights “within four years”.  This is clearly not orbital flight, and I expect that “half hour” will eventually be found to mean “quarter hour”.  He also claimed that Iran will be ready for manned orbital flight within 10 years.  By then, the intrepid Iranonaut may find himself unnoticed among the swarms of Western space tourists.

Who, if anyone, should care about this monkey mission?  Israel, which is within reach of Iranian ballistic missiles such as the one used in this launch.

In other satellite-related Iranian news, I see from a posting at that Iran is confiscating satellite dishes from its citizens as part of its “cultural offensive”.  Certainly, “offensive” is the operative word here.

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