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MSI Announces the CX420 and CR420 Notebooks

The latest 14" models in the MSI Classic series, the CX420 and CR420, boast the latest Intel Core i Series processors. The CX420 is also equipped with a built-in ATi Radeon HD5470 discrete graphics card with 1GB DDR3 memory and an external casing coated with MSI's exclusive Cross-Hatch Color Film Print patterning. With a lightweight as well as fashionable appearance, they are the best companions for next-generation audiovisual enjoyment.

MSI Notebook Marketing Director Sam Chern points out that the CX420 and CR420 represent the latest notebook models in the MSI Classic Series. They are configured with New 2010 Intel Core processor. Not only are the lid and palm rest area coated with bright, scratch-resistant Cross-Hatch Color Film Print (CFP) patterning, the models also come equipped with the Chiclet keyboard and seamless touch-pad, with the exterior utilizing MSI's exclusive "wedge" technique. These ultra-thin, 14" models weigh less than 2.2 kg, enabling users to enjoy high mobility in addition to powerful audiovisual and processing performance.

Great Entertainment with Fashionable Technology

Cross-Hatch Color Film Print Pattern: The lid and palm rest area of the CX420 and CR420 are coated with MSI's exclusive Cross-Hatch CFP patterning, which not only provides scratch-resistant protection but also reveals an exquisite texture that exhibits a radiant gloss. With a perfect 45-degree angle, the case is constructed with MSI's "wedge" design techniques, making the notebook slimmer, lighter (less than 2.2 kg) more portable and the perfect mobile entertainment companion.

MSI's unique Chiclet keyboard: The CX420 and the CR420 feature the latest in Chiclet keyboards, to give you an optimum typing experience whatever task you happen to be performing: word processing, instant messaging, etc. You also don't have to worry about touching other keys by accident. Together with the smooth cross-hatch CFP patterning on the lid and palm rest area, the models exhibit a distinctive minimalist style.

Classic Seamless Touch-pad: The CX420 and CR420 are equipped with MSI's distinctive seamless touch-pad. This touch-pad also utilizes the full-textured cross-hatch CFP patterning for the maximum in user enjoyment.

Wonderful Audiovisual Performance

New 2010 Intel core processor: The CX420 and CR420 feature the latest Intel Arrandale platform, which is equipped with the brand-new Intel Core i Series processor and HM55 chipset. Power consumption is even lower than that of the previous generation, with 15% extended battery life. They are also configured with Hyper-Threading technology. The performance of its integrated graphics core has also significantly improved, offering users excellent processing and display efficiency.

Built-in ATi Radeon HD 5470 Discrete Graphics Adaptor (1 GB DDR3 VRAM): CX420 has a built-in high-end ATi Radeon HD 5470 discrete graphics card equipped with 1GB DDR3 video memory. Its outstanding graphics performance and ultra-fine display offer users a color-rich and superior visual experience.

16:9 Theater-Class LED-Backlit Screen: CX420 and CR420 are powered by a 14" LED-backlit display with 16:9 cinematic aspect ratio and high resolution. The screen's viewable area is extended by 14% so that no horizontal black bars will ever get in the way again when you are watching high-quality DVD movies.

Exclusive Innovative Energy-Efficient Technology

Exclusive GPU Boost Technology: CX420 is equipped with MSI's exclusive GPU Boost technology to help you achieve a perfect balance between audiovisual performance and battery life! When running an application that requires high-performance power in image processing, just press the button and the CX420 will automatically switch to high-performance external display mode. When you need to work in an environment that requires long battery life, just press the Battery button and the machine will switch to the integrated display mode and shut down the external graphics card to preserve battery power.

Exclusive ECO Engine Energy-Efficient Technology: The CX420 and the CR420 come with MSI's exclusive ECO Engine energy-saving technology that allows you to choose from five power management modes: Gaming, Movie, Presentation, Office, and Turbo Battery. These modes automatically adjust screen brightness, power switch, hibernation settings, processor performance etc., so that battery power can be used in a more flexible manner and therefore effectively extended.

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Skylab

In 1968, the Apollo Applications Program was created to look into science missions that could be performed with the surplus Apollo hardware. Much of the planning centered on the idea of a space station, which eventually spawned theSkylab program. Skylab was launched using a two-stage Saturn V, sometimes called a Saturn INT-21.[2] It was the only launch not directly related to the Apollo lunar landing program.

Originally it was planned to use a 'wet workshop' concept, with a rocket stage being launched into orbit by a Saturn 1B and its spent S-IVB outfitted in space, but this was abandoned for the 'dry workshop' concept: An S-IVB stage from a Saturn IB was converted into a space station on the ground and launched on a Saturn V. A backup, constructed from a Saturn V third stage, is now on display at the National Air and Space Museum.

Three crews lived aboard Skylab from May 25, 1973 to February 8, 1974, with Skylab remaining in orbit until July 11, 1979.

Proposed post-Apollo developments

The (canceled) second production run of Saturn Vs would very likely have used the F-1A engine in its first stage, providing a substantial performance boost.[16] Other likely changes would have been the removal of the fins (which turned out to provide little benefit when compared to their weight); a stretched S-IC first stage to support the more powerful F-1As; and uprated J-2s for the upper stages.

A number of alternate Saturn vehicles were proposed based on the Saturn V, ranging from the Saturn INT-20 with an S-IVB stage and interstage mounted directly onto an S-ICstage, through to the Saturn V-23(L)[17] which would not only have five F-1 engines in the first stage, but also four strap-on boosters with two F-1 engines each: giving a total of thirteen F-1 engines firing at launch.

The Space Shuttle was initially conceived of as a cargo transport to be used in concert with the Saturn V, even to the point that a "Saturn-Shuttle," using the current orbiter and external tank, but with the tank mounted on a modified, fly-back version of the S-IC, would be used to power the Shuttle during the first two minutes of flight, after which the S-IC would be jettisoned (which would then fly back to KSC for refurbishment) and the Space Shuttle Main Engines would then fire and place the orbiter into orbit. The Shuttle would handle space station logistics, while Saturn V would launch components. Lack of a second Saturn V production run killed this plan and has left the United States without a heavy-lift booster. Some in the U.S. space community have come to lament this situation, as continued production would have allowed theInternational Space Station, using a Skylab or Mir configuration with both U.S. and Russian docking ports, to have been lifted with just a handful of launches, with the "Saturn Shuttle" concept possibly eliminating the conditions that caused the Challenger Disaster in 1986.

The Saturn V would have been the prime launch vehicle for the canceled Voyager Mars probes, and was to have been the launch vehicle for the nuclear rocket stage RIFT test program and the later NERVA.

Successors

U.S. proposals for a rocket larger than the Saturn V from the late 1950s through the early 1980s were generally called Nova. Over thirty different large rocket proposals carried the Nova name, but none were developed.

Wernher von Braun and others also had plans for a rocket that would have featured eight F-1 engines in its first stage allowing it to launch a manned spacecraft on a direct ascent flight to the Moon. Other plans for the Saturn V called for using a Centaur as an upper stage or adding strap-on boosters. These enhancements would have increased its ability to send large unmanned spacecraft to the outer planets or manned spacecraft to Mars.

In 2006, NASA, as part of the upcoming Constellation Program that would replace the Space Shuttle after 2010, unveiled plans to construct the heavy-lift Ares V rocket, a Shuttle Derived Launch Vehicle using some existing Space Shuttle and Saturn V infrastructure. Named in homage of the Saturn V, the original design, based on the Space Shuttle External Tank, was 360 ft (110 m). tall, and powered by five Space Shuttle Main Engines (SSMEs) and two uprated five-segment Space Shuttle Solid Rocket Boosters, which a modified variation would be used for the crew-launched Ares I rocket. As the designed evolved, the Ares V was slightly modified, with the same 33 ft (10 m) diameter as that of the Saturn V's S-IC and S-II stages, and in place of the five SSMEs, five RS-68 rocket engines, the same engines used on the Delta IV EELV, would be used. The switch from the SSME to the RS-68 was due to the steep price of the cost of the SSME, as that it would be thrown away along with the Ares V core stage after each use, while the RS-68 engine, which is expendable, is cheaper, simpler to manufacture, and more powerful than the SSME. In 2008, NASA again redesigned the Ares V, lengthening and widening the core stage and added an extra RS-68 engine, giving the launch vehicle a total of six engines. The six RS-68B engines, during launch, will be augmented by two "5.5-segment" SRBs instead of the original five-segment designs, although no decision has yet been made on the number of segments NASA would be using on the final design.[1] If the six RS-68B/5.5-segment SRB variant is used, the vehicle would have a total of approximately 8,900,000 lbf (39.6 MN) of thrust at liftoff, making it more powerful than the Saturn V or the Soviet/Russian Energia boosters, but less than 50–43 MN for the Soviet N-1. An upper stage, known as the Earth Departure Stage and based on the S-IVB, will utilize a more advanced version of the J-2 engine known as the "J-2X," and will place the Altair lunar landing vehicle into a low earth orbit. At 381 ft (116 m) tall and with the capability of placing 180 tons[vague] into low Earth orbit, the Ares V will surpass the Saturn V and the two Soviet/Russian superboosters in both height, lift, and launch capability.

The RS-68B engines, based on the current RS-68 and RS-68A engines built by the Rocketdyne Division of Pratt and Whitney (formerly under the ownerships of Boeing and Rockwell International), produce less than half the thrust per engine as the Saturn V's F-1 engines, but are more efficient and can be throttled up or down, much like the SSMEs on the Shuttle. The J-2 engine used on the S-II and S-IVB will be modified into the improved J-2X engine for use both on the Earth Departure Stage (EDS) as well as on the second stage of the proposed Ares I. Both the EDS and the Ares I second stage would use a single J-2X motor, although the EDS was originally designed to use two motors until the redesign employing the five (later six) RS-68Bs in place of the five SSMEs.

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Lunar mission launch sequence

The Saturn V carried all Apollo lunar missions. All Saturn V missions launched from Launch Complex 39 at the John F. Kennedy Space Center. After

the rocket cleared the launch tower, mission control transferred to the Johnson Space Center in Houston, Texas.

An average mission used the rocket for a total of just 20 minutes. Although Apollo 6 and Apollo 13 experienced engine failures, the onboard com

puters were able to compensate by burning the remaining engines longer, and none of the Apollo launches resulted in a payload loss.

The first stage burned for 2.5 minutes, lifting the rocket to an altitude of 42 miles (68 km) and a speed of 6,164 miles per hour (9,920 km/h) and burning 2,000,000 kilograms (4,400,000 lb) of propellant.

At 8.9 seconds before launch, the first stage ignition sequence started. The center engine ignited first, followed by opposing outboard pairs at 300-millisecond intervals to reduce the structural loads on the rocket. When thrust had been confirmed by the onboard computers, the rocket was "soft-released" in two stages: first, the hold-down arms released the rocket, and second, as the rocket began to accelerate upwards, it was slowed by tapered metal pins pulled through dies for half a second. Once the rocket had lifted off, it could not safely settle back down onto the pad if the engines failed.

It took about 12 seconds for the rocket to clear the tower. During this time, it yawed 1.25 degrees away from the tower to ensure adequate clearance despite adverse winds. (This yaw, although small, can be seen in launch photos taken from the east or west.) At an altitude of 430 feet (130 m) the rocket rolled to the correct flight azimuth and then gradually pitched down until 38 seconds after second stage ignition. This pitch program was set according to the prevailing winds during the launch month. The four outboard engines also tilted toward the outside so that in the event of a premature outboard engine shutdown the r

emaining engines would thrust through the rocket's center of gravity. The Saturn V quickly accelerated, reaching 1,600 feet per second (490 m/s) at over 1 mile (1,600 m) in altitude. Much of the early portion of the flight was spent gaining altitude, with the required velocity coming later.

Apollo 11 S-IC separation

At about 80 seconds, the rocket experienced maximum dynamic p

ressure (Max Q). The dynamic pressure on a rocket varies with air density and the square of relative velocity. Although velocity continues to increase, air density decreases so quickly with altitude that dynamic pressure falls below Max Q.

Acceleration increased during S-IC flight for two reasons: decreasing propellant mass; and increasing thrust as F-1 engine efficiency improved in the thinner air at altitude. At 135 seconds, the inboard (center) engine shut down to limit acceleration to 4 g (40 m/s2). The other engines continued to burn until either oxidizer or fuel depletion as detected by sensors in the suction assemblies. First stage separation was a little less than one second after cutoff to allow for F-1 thrust tail-off. Eight small solid fuel separation motors backed the S-IC from the interstage at an altitude of about 67 kilometers (42 mi).

The first stage continued ballistically to an altitude of about 109 kilomet

ers (68 mi) and then fell in the Atlantic Ocean about 560 kilometers (350 mi) downrange.

S-II sequence

After S-IC separation, the S-II second stage burned for 6 minutes and propelled the craft to 109 miles (176 km) and 15,647 mph (25,182 km/h– 7.00 km/s), close to orbital velocity.

For the first two unmanned launches, eight solid-fuel ullage motors ignited for four seconds to give positive acceleration to the S-II stage, followed by start of the five J-2 engines. For the first seven manned Apollo missions only four ullage motors were used on the S-II, and they were eliminated completely f

or the final four launches. About 30 seconds after first stage separation, the interstage ring dropped from the second stage. This was done with an inertially fixed attitude so that the interstage, only 1 meter from the outboard J-2 engines, would fall cleanly without contacting them. Shortly after interstage separation the Launch Escape System was also jettisoned. SeeApollo abort modes for

more information about the various abort modes that could have been used during a launch.

About 38 seconds after the second stage ignition the Saturn V switched from a preprogrammed trajectory to a "closed loop" or Iterative Guidance Mode. The Instrument Unit now computed in real time the most fuel-efficient trajectory toward its target orbit. If the Instrument Unit failed, the crew could switch control of the Saturn to the Command Module

's computer, take manual control, or abort the flight.

About 90 seconds before the second stage cutoff, the center engine shut down to reduce longitudinal pogo oscillations. A pogo suppressor, first flown on Apollo 14, stopped this motion but the center engine was still shut down early to limit acceleration G forces. At around this time, the LOX flow rate decreased, changing the mix ratio of the two propellants, ensuring that there would be as little propellant as possible left in the tanks at the end of second stage flight. This was done at a predetermined delta-v.

Five level sensors in the bottom of each S-II propellant tank were armed during S-II flight, allowing any two to trigger S-II cutoff and staging when they were uncovered. One second after the second stage cut off it separated and several seconds later the third stage ignited. Solid fuel retro-rockets mounted on the interstage at the top of the S-II fired to back it away from the S-IVB. The S-II impacted about 4200 km (2,300 miles) from the lau

nch site.

S-IVB sequence

Unlike the two-plane separation of the S-IC and S-II, the S-II and S-IVB stages separated with a single step. Although it was constructed as part of the third stage, the interstage remained attache

d to the second stage.

During Apollo 11, a typical lunar mission, the third stage burned

for about 2.5 minutes until first cutoff at 11 minutes 40 seconds. At this point

it was 2640 km downrange and in a parking orbit at an altitude of 188 km and velocity of 7790 m/sec. The third stage remained attached to the spacecraft while it

orbited the Earth two and a half times while astronauts and mission controllers prepared for tra

nslunar injection (TLI).

This parking orbit is quite low by Earth orbit standards, and it would have been short-lived due to aerodynamic drag. This was not a problem on a lunar mission because of the short stay in the parking orbit. The S-IVB also continued to thrust at a low level with hydrogen vents to settle the propellants in their tanks, and this thrust easily exceeded aerodynamic drag.

For the final three Apollo flights, the temporary parking orbit was even lower (approximately 150 kilometers (93 mi)), to increase payload for these missions. For the two Earth orbit missions of the Saturn V, Apollo 9 and Skylab, the orbits were much higher and more typical of manned orbital missions.

On Apollo 11, TLI came at 2 hours and 44 minutes

after launch. The S-IVB burned for almost six minutes giving the spacecraft a velocity close to the Earth's escape velocity of 11.2 km/s (40,320 km/h; 25,053 mph). This gave an energy-efficient transfer to lunar orbit with the moon helping to capture the spacecraft with a minimum of CSM fuel consumption.

About 40 minutes after TLI the Apollo Command Service Module (CSM) separated from the third stage, turned 180 degrees and docked with the Lunar Module(LM) that rode below the CSM during launch. The CSM and LM separated from the spent third stage 50 minutes later.

If it were to remain on the same trajectory as the spacecraft, the S-IVB could have presented a collision hazard so its remaining propellants were vented and the auxiliary propulsion system fired to move it away. For lunar missions before Apollo 13, the S-IVB was directed toward the moon's trailing edge in its orbit so that the moon would slingshot it beyond earth escape velocity and into solar orbit. From Apollo 13 onwards, controllers directed the S-IVB to hit the Moon.[15]Seismometers left behind by previous missions detected the impacts, and the information helped map the inside of the Moon.

Apollo 9 was a special case; although it was an earth orbital mission, after spacecraft separation its S-IVB was fired out of earth orbit into a solar orbit.

On September 3, 2002, Bill Yeung discovered a suspected asteroid, which was given the discovery designation J002E3. It appeared to be in orbit around the Earth, and was soon discovered from spectral analysis to be covered in white titanium dioxide paint, the same paint used for the Saturn V. Calculation of orbital parameters identified the apparent asteroid as being the Apollo 12 S-IVB stage. Mission controllers had planned to send Apollo 12's S-IVB into solar orbit, but the burn after separating from the Apollo spacecraft lasted too long, and hence it did not pass close enough to the Moon, remaining in a barely-stable orbit around the Earth and Moon. In 1971, through a series of gravitational perturbations, it is believed to have entered in a solar orbit and then returned into weakly-captured Earth orbit 31 years later. It left Earth orbit again in June 2003. Another near-earth object, discovered in 2006 and designated 6Q0B44E, may also be part of an Apollo spacecraft.

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Saturn V

The Saturn V (pronounced "Saturn Five") was a multistage liquid-fuel expendable rocket used by NASA's Apollo and Skylab programs from 1967 until 1973. In total NASA launched thirteen Saturn V rockets with no loss of payload. It remains the largest and most powerful launch vehicle ever brought to operational status from a height, weight and payload standpoint. The Soviet rockets Energia and the unsuccessful N1 had slightly more takeoff thrust.

The largest production model of the Saturn family of rockets, the Saturn V was designed under the direction of Wernher von Braun and Arthur Rudolph at theMarshall Space Flight Center in Huntsville, Alabama, with Boeing, North American Aviation, Douglas Aircraft Company, and IBM as the lead contractors. Von Braun's design was based in part on his work on the "Aggregate" series of rockets, especially the A-10, A-11, and A12 in Germany during World War II. The three stages of the Saturn V were developed by various NASA contractors, but following a sequence of mergers and takeovers all of them are now owned by Boeing.

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