What was the longest mission that you have ever done?  Have you ever done any aborts?

The longest mission I've ever worked lasted about 17 days. Flight controllers are never scheduled to work more than 10 shifts without a day off, so nobody but the crew worked that entire mission. For example, I'm

scheduled to work 10 shifts on STS-101, starting on Easter Sunday. Since I worked all last week, including Friday, I MUST take today (Saturday) off. If Monday's launch is scrubbed, or if the mission is extended, I may end up working more than 10 shifts in a row, but we never PLAN to do that "going in".

There's only been one abort in the Shuttle Program, STS-51F. That was an Abort To Orbit (ATO), where a main engine was shut down late enough in ascent that the remaining two engines could still achieve a safe orbit at a slightly lower altitude than planned. STS-51L doesn't qualify as an abort because the Shuttle was destroyed before anyone had a chance to react and actually declare an abort. I wasn't a flight controller for 51F, but I've simulated a number of aborts. We did at least 4 of them early yesterday morning with the STS-101 crew in the simulator just before they flew their T-38s to KSC to prepare for launch. Since I'm the STS-101 Rendezvous FDO, I'm not at the FDO Console for launch. Instead, I help the Ascent FDO, Lisa Shore, from a "back room" console. During launches, my job is to make sure the Shuttle is steered into the correct orbit so we can complete the rendezvous with International Space Station (ISS). If the Shuttle does an ATO and can't reach the ISS altitude, it's my job to figure out how high the Shuttle can go and propose ISS orbit-lowering maneuvers to meet the Shuttle "half way".  If ISS can't spare the gas to do this, then we'd have to bring the Shuttle home after several days and try again later with another launch.

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Is it possible for the Orbiter to be in GEO or even just stay in GEO for a few minutes?

I'm doing fine, although I'm as busy as you are getting ready for my next mission. I spent over 10 hours today in a simulation docked to the Space Station while a Chinese rocket's upper stage threatened to smash into us

tomorrow. The sim will last all night, and I'll have to see how things turn out Friday morning when I get back on console. Hopefully, my fellow-FDOs will figure out an evasive maneuver, but it must be performed very gently so as not to damage the Space Station's delicate solar panels.  You've asked a very interesting question. By not having to stay at GEO height, about 19300 nm up, we can save a lot of propellant because we only have to raise one end of our orbit to get there. Our orbit will be a roller-coaster path. One end is at GEO height, and the other end will be just barely above earth's atmosphere at 100 nm. This egg-shaped elliptical orbit is called a GEO transfer.

If the Orbiter starts in a typical orbit a few hundred miles up, getting into a GEO transfer requires a speed increase of about 8000 fps. Because the Orbiter weighs over 200000 lbs, it consumes about 20 lbs of propellant for each fps in speed it adds. That's 160000 lbs of propellant required to get the Orbiter into GEO. Now, when the Orbiter arrives in its initial orbit a few hundred miles up, it's only carrying at most 15000 lbs of propellant, and some 5000 lbs of that's reserved for the return trip home! The rest of the Orbiter's weight is devoted to wings, a fuselage, landing gear, and crew accommodations.  Of course, if the Orbiter deploys an unmanned satellite with its own rocket engine, the trip to GEO can be one-way. These satellites typically weigh

less than a tenth what the Orbiter does, so GEO transfer can be achieved with only a modest amount of propellant. Maybe someday we'll have a manned spacecraft capable of reaching GEO and higher orbits, but it will look very different from an Orbiter!

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Is it possible for a satellite to have a special defense system, so that if there was a meteor shower it could just pop out.  I would like to do that, but my one concern is that it might be too much weight and it may be too many systems for the satellite to handle?

I'm not sure what you mean by "just pop out", but shielding against meteors (and radiation from solar flares) is a good idea if, as you say, too much weight isn't added. Shielding can also provide thermal protection so the

sunward side of your satellite doesn't get too hot and the shaded side doesn't get too cold. Obviously, the thicker/heavier the shielding, the more protection (good) and weight (bad) it contributes. Perhaps you can

develop a "weight budget" for your satellite with an item in it for shielding.

One way you can get the most from every pound of shielding you provide is to construct it in multiple layers. Something which can penetrate the first layer gets cut down to size or even vaporized, leaving the second

layer relatively intact. Thus, two thin layers can provide as much protection as a thicker single layer which weighs lots more.

You also might consider placing sensitive components like electronics and critical elements like propellant tanks behind external structures like a "dish" antenna which can act like a shield. A small hole in an antenna probably won't affect communications at all, but any hole in a propellant tank would certainly end the satellite's useful lifetime early or even cause a catastrophic explosion.

As a Mission Specialist working on the satellite's design, do you get to deploy it?

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Why do you like space?

I like space because it's our New Frontier, just like the American West was 150 years ago. Earth is running out of unvisited places to explore, so it's time to start traveling to other worlds and see what's out there!

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What does a person who works FDO do?

On console, a Flight Dynamics Officer (FDO, pronounced "fido") leads a team of from 3 to a dozen other back room" flight controllers. The team's size depends on the mission phase being supported. It's large during launch and landing; smaller on orbit. The Flight Dynamics Team's primary duty is determining and predicting the Shuttle's path in space, called its trajectory. We do trajectory determination using ground-based RADAR and communications satellites. Soon, we'll be using Global Positioning System (GPS) satellites for this job too. In addition to trajectory determination and prediction, the Flight Dynamics Team plans trajectory changes by the Shuttle's rocket engines necessary to accomplish mission objectives. These objectives include avoiding collisions with orbiting satellites and space junk, achieving redezvous and safe separation with International Space Station "Alpha", and return to earth. A typical FDO spends less than 25% of working hours on console, including training time in sims. Remaining time is devoted to meetings, procedures development, software development, and so on. A college education in science, math, or engineering is essential. Both oral and written communications skills, mixed with a good measure of diplomacy, are key to success as well.