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Expedition 10 preview
International Space Station officials at Johnson Space Center provide a detailed preview of the Expedition 10 mission during this pre-launch press conference. (19min 15sec file)
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Expedition 9 recap
A review of the soon-to-be completed Expedition 9 mission aboard the International Space Station is presented by mission managers at Johnson Space Center. (32min 38sec file)
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Checking their ride
Expedition 10 commander Leroy Chiao, flight engineer Salizhan Sharipov and Russian taxi cosmonaut Yuri Shargin climb aboard their Soyuz capsule for a fit check in advance of launch to the International Space Station. (1min 45sec file)
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Spirit panorama
This amazing panorama of the martian surface at Columbia Hills was taken by the Spirit rover. Expert narration is provided by camera scientist Jim Bell. (2min 12sec file)
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Update on Mars rovers
Mars Exploration Rover project manager Jim Erickson and panoramic camera lead scientist Jim Bell offer comments on the status of the Spirit and Opportunity missions (1min 33sec file)
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Delta rocket assembly
The first stage of Boeing's Delta 2 rocket that will launch NASA's Swift gamma-ray burst detection observatory in November is erected on pad 17A at Cape Canaveral, Florida. (4min 52sec file)
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Solid boosters arrive
The three solid-fueled rocket boosters for the Boeing Delta 2 vehicle that will launch the Swift satellite are hoisted into the pad 17A mobile service tower. (4min 55sec file)
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SRBs go for attachment
The mobile service tower carries the solid boosters into position for attachment to the Delta 2 rocket's first stage. (3min 08sec file)
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Swift nose cone
The two halves of the 10-foot diameter rocket nose cone that will enclose NASA's Swift satellite during launch aboard a Boeing Delta 2 vehicle are lifted into the pad 17A tower. (4min 26sec file)
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Rutan explains SpaceShipOne rolls
Posted: October 2, 2004

Burt Rutan, designer of SpaceShipOne, said in a website posting Saturday that more than two dozen rolls experienced by pilot Mike Melvill during last week's Ansari X Prize flight occurred in what amounted to a space environment and that the vehicle was never in any danger.

Melvill flew SpaceShipOne to an altitude of 337,600 feet - 63.9 miles - last Wednesday in the first of two flights needed to win the $10 million X Prize, which goes to the first team to build and launch a commercial spacecraft into suborbital space twice in two weeks. Rutan plans to send SpaceShipOne aloft on its second X Prize flight Monday morning. The identity of the pilot has not yet been announced.

Fifty seconds or so into powered flight last week, SpaceShipOne began rolling about its vertical axis, alarming reporters on the ground who feared the craft was out of control. Even the official commentators discussing the flight on an X Prize webcast expressed alarm.

But Melvill stopped the roll as the ship climbed out of the atmosphere and he completed a flawless re-entry and landing. It was reported at the time that flight controllers had ordered Melvill to shut down the craft's engine and that the pilot delayed long enough to ensure he reached the minimum 100-kilometer altitude required by the X Prize competition.

Not true, said Rutan. Here is the text of his explanation:

"The complex reason on why the rolling departure occurred will be described in a report we will post at a later date. What I am intending to do here is merely address some of the incorrect rumors about the rolls that have been seen in various news stories and web discussion groups.

"While the first roll occurred at a high true speed, about 2.7 Mach, the aerodynamic loads were quite low (120 knots equivalent airspeed) and were decreasing rapidly, so the ship never saw any significant structural stresses. The reason that there were so many rolls was because shortly after they started, Mike was approaching the extremities of the atmosphere. Nearly all of the 29 rolls that followed the initial departure were basically at near-zero-q, thus they were a continuous rolling motion without aerodynamic damping, rather than the airplane-like aerodynamic rolls seen by an aerobatic airplane. In other words, they were more like space flight than they were like airplane flight. Thus, Mike could not damp the motions with his aerodynamic flight controls.

"Mike elected to wait until he feathered the boom-tail in space, before using the reaction control system thrusters (RCS) to damp the roll rate. When he finally started to damp the rates he did so successfully and promptly. The RCS damping, to a stable attitude without significant angular rates was complete well before the ship reached apogee (337,600 feet, or 103 Km). That gave mike time to relax, note his peak altitude, and then pick up a digital high-resolution camera and take some great photos out the windows. Those photos are now being considered for publication by a major magazine.

"While we did not plan the rolls, we did get valuable engineering data on how well our RCS system works in space to damp high angular rates. We also got a further evaluation of our Care-free Reentry capability, under a challenging test condition. As seen on the videos of the flight, the ship righted itself quickly and accurately without pilot input as it fell straight into the atmosphere. No other winged, horizontal-landing spaceship (X-15, Buran, Space Shuttle) has this capability.

"Some publications have stated that Mike defied a request to shut down the motor and let it run a few more seconds in order to reach 100 Km altitude. This is not true. While a Mission Control aerodynamist did discuss a possible abort a few seconds earlier, Mike immediately shut down the motor on the first advisory call over the radio. Mike himself was monitoring the apogee predictor during the initial rolls and was in the process of going for the thrust termination switch as he heard the advisory call."