21 February 2008

USA 193


SM-3 Leaving its Verticle Launch Tube

The Notice to Airmen and Mariners- the NOTAM- is the key to this thing. Of course the decision-making that went into the operation has been going on for months. The issuance of the warning area is the last bit that provided us the operational location, the target and the timing.

The amateurs began to extrapolate from there, and you can see the whole scenario as derived from unclassified sources. But hang on a second. There are a lot of moving parts to the story.

Let's recap the bids on the remarkable circumstances that brought the USS Lake Erie, it's SPY-1 Aegis radar system and specially configured Standard Missile-3 to a rendezvous with destiny 130 miles above the glistening blue Pacific northwest of the welcoming island of Maui.

Actually, it was not destiny with which the SM-3 collided, but a very expensive satellite produced by one of America's Aerospace Mega Corporations. According to open source information, the satellite had gone stupid shortly after launch into a “national security” orbit, and the NRO was unable to regain control of the platform.

What goes up, must come down, as they say, and so let's get the boring science stuff out of the way first. That should be an  improvement with the learned commentators who have been yammering away about their “feelings” on things on which they apparently have no clue.

Orbits are selected with the function of the vehicle in mind. There are only so many ways to skin the cat. If you desire a predictable look at weather patterns, or a reliable place through which to channel communications, a very high orbit is required. That permits the space vehicle to maintain a static position in reference to its ground track- "geostationary" is the term of art.

If you wish to look at people in their hot-tubs, you need to be a lot closer. You do that through a low-earth orbit, which has the disadvantage of only passing over any particular place on earth every hour and a half. Special applications require long dwell time over specific target areas but do not need the granularity of an imaging system can use the fantastic egg-shaped Molnaya orbit that hurtles impossibly high, holding the target in view from rise to set for hours, then whizzing quickly at low altitude around the part of the earth to rise once more majestically in space.

The application is the key, and since the NRO has not chosen to share it with us in an unclassified manner, let's just make an assumption that this particular vehicle was a large, low-earth orbit vehicle with a finite life span, and since it failed to initiate, had a full bag of hydrazine fuel onboard intended to last (at least) the entire mean mission duration.

Only three sorts of people are very concerned about these things: the people that launch them, the people that are targeted by them, and an eccentric collection of people who watch them as a hobby.

The Air Force Space Command is one of the organizations that tracks and reports the status of things on orbit. This particular satellite was designated “USA 193,” since that is the naming convention for otherwise undisclosed space vehicles. They have known, as have the other space-faring corporations and nation-states, that the large satellite has been un-commanded and gradually losing altitude since the beginning of its life in the heavens.

Things have been falling out of the sky since mankind began to put them up there, and most have burned up harmlessly in the atmosphere on re-entry, the parts that survived crashing harmlessly into the world ocean or into the desert.

Another couple issues. National security orbits tend to be inclined north and south, while manned activities and deeper space applications tend to be launched easterly into the rotation of the earth, to capitalize on the free speed. Before Challenger went sky-high, there had been a plan to launch the Shuttles out of Vandenburg AFB in California, which has a clear shot to the south over the water and avoids all major population centers.

The failure of the “O” Rings on Challenger is one of the turning points in human history in space, and that would be worth a prolonged discussion. Space Launch Complex Six at Vandenburg cost $3 Billion dollars, and was to be the home for classified shuttle missions. Unfortunately, the extra weight required to fix the booster meant that the Shuttle had to launch to the east, out of Kennedy on Florida's Space Coast.

The whole astonishing enterprise had to take another course.

I had a chance to visit the ghost launch complex a decade ago, a twin to the one at Cape Canaveral, and it is abandoned. Really amazing, in terms of what the human mind can devise, construct and then throw away.

Which brings us generally around, through the Anti-Ballistic Missile Treaty with the former Soviet Union, as to why a Navy ship should be the one American capability to shoot down an errant satellite.

Back in the day, the Soviets and Americans were in the process of deploying advanced capabilities to shoot down each other's nuclear ballistic missiles. It was going to be very expensive, and very destabilizing. The Anti-ballistic missile treaty was the result, signed in 1972. The Russians retained the capability to defend Moscow, and the Americans decided to protect some missile silos in the Dakotas. The latter capability was abandoned a few years later.

The Air Force was executive agent for all things space related, and was determined to keep the lead. In 1982, a missile launched from an F-15 in zoom climb successfully killed a target satellite in low-earth orbit.

The capability made the Congress nervous, since it implied an unlimited and unmanageable new arms race. There was considerable unease about provoking the Soviets into developing a capability that could blind American reconnaissance capabilities. A ban was imposed on the project in 1985.

There the matter rested, even as the Reagan Administration's Star Wars initiative began its multi-decade-long space mission to boldly go where no Agency had ever gone before.

It is still going there, though a curious thing happened. The Navy had funded the SPY-1 radar program to provide comprehensive Fleet Air Defense against the hoards of Soviet manned bombers that were being armed with supersonic high altitude missile systems. It turned out to be so good at tracking things far away that the software had to be re-written to make the computer not pay attention to satellites.

It was only a matter of time until someone realized it was possible to do exactly the reverse: tune the radar to look only at things in space. A complete anti-satellite capability only required a new missile to get all the way to low earth orbit.

That brings us to the decision to take down the satellite. Let's get the conspiracy theories on the table. In general order, they are these:

It is an attempt to keep really spooky secrets. The Pentagon is afraid the satellite will fall into the hands of our enemies.

The Pentagon is hoping to bolster support for the missile defense system by demonstrating that it has many other side benefits, such as the ability to shoot down rogue satellites full of poisonous gas.

The Pentagon wants the public to think about something besides Iraq and Afghanistan.

The Pentagon is sending a signal to the Chinese, who blew up a satellite last year.

Well, the answer is yes. The secrets of USA 193 probably could not be compromised regardless of where the isolated bits wound up, but on the whole, it is better to have them on the bottom on the ocean rather than in Syria, Iran, China or Russia.

Proof that the money spent on the SPY-1 and SM-3 actually produced something that worked is useful, both from internal and external purposes, particularly with a new administration coming along soon.

There really is a minor public health threat from the toxic hydrazine fuel, and being a big frozen lump shielded in stainless steel, it might actually have made it back to earth.

Those pesky Chinese need to be reminded that the Sole Superpower is not a paper tiger, and periodically the Russians need a reminder about who spent who into the poorhouse.

The NOTAM went into effect last night, and USS Lake Erie, flanked by two other Aegis-equipped warships, was on station. Secretary of Defense Bob Gates gave the order to execute from Washington, which was relayed by satellite to the operations area.

USA 193 rose in the sky to the southwest of the NOTAM area at 27 minutes after the hour, headed for apogee over the NOTAM area at the three-zero mark. The engagement window was about ten seconds, an eternity in Aegis terms, and the launch and interception was conducted without a hitch.

Pretty remarkable.

Being hit at somewhere north of 17,000 miles an hour, USA 193 turned from a sophisticated if inarticulate spacecraft into a collection of trajectories close to the original orbital inclination, but spreading to either side.

Fragments leaving the cloud with the lowest orbital velocity hit the upper atmosphere soon after the collision. Nearly all of the satellite will be down within two days, and all of it within about a month.

Amateur astronomers observed numerous trails across the sky from the Prince George Astronomical Observatory in western Canada, where they had gathered to observe the total lunar eclipse. Did I mention that the whole evolution happened in a total eclipse of the moon?

I must have forgotten in all the excitement.

Oh, and the Chinese thing last year? They blew up a weather satellite that was going dead. It was in geo-synchronous orbit, way up there. The junk cloud from that event, all the little bits whirring at 17,000 miles an hour, will be on orbit for centuries.

Copyright 2008 Vic Socotra
www.vicosoctra.com

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