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SpaceX Rocket Launch Succeeds, But Landing Test Doesn't

frank249 Re:Twitter: Ran out of Hydralic fluid (213 comments)

Elon Musk @elonmusk Hydraulics are usually closed, but that adds mass vs short acting open systems. F9 fins only work for 4 mins. We were ~10% off.

about three weeks ago
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SpaceX Rocket Launch Succeeds, But Landing Test Doesn't

frank249 Re:Reinventing the wheel -- Am I missing something (213 comments)

NASA has used parachutes for rentry. Several new technologies needed to be developed and tested to facilitate successful launch and recovery of both stages of the SpaceX reusable rocket launching system. Following the completion of the third high-altitude controlled-descent test, and the completion of the third low-altitude flight of the second-generation prototype test vehicle (plus eight flights of the first-generation Grasshopper prototype flight test vehicle), SpaceX indicated that they are now able to consistently "reenter from space at hypersonic velocity, restart main engines twice, deploy landing legs and touch down at near zero velocity."[29]

The technologies that were developed for this program, some of which are still being refined, include::

        restartable ignition system for the first-stage booster[17] Restarts are required at both supersonic velocities in the upper atmosphere—in order to decelerate the high velocity away from the launch pad and put the booster on a descent trajectory back toward the launch pad—and at high transonic velocities in the lower atmosphere—in order to slow the terminal descent and to perform a soft landing.[30]
        new attitude control technology—for the booster stage and second stage—to bring the descending rocket body through the atmosphere in a manner conducive both to non-destructive return and sufficient aerodynamic control such that the terminal phase of the landing is possible.[30] This includes sufficient roll control authority to keep the rocket from spinning excessively as occurred on the first high-altitude flight test in September 2013, where the roll rate exceeded the capabilities of the booster attitude control system (ACS) and the fuel in the tanks "centrifuged" to the side of the tank shutting down the single engine involved in the low-altitude deceleration maneuver.[21][31] The technology needs to handle the transition from the vacuum of space at hypersonic conditions, decelerating to supersonic velocities and passing through transonic buffet, before relighting one of the main-stage engines at terminal velocity.[19]
        throttleable rocket engine technology is required to reduce engine thrust because the full thrust of even a single Merlin 1D engine exceeds the weight of the nearly empty booster core.[32][33]
        terminal guidance and landing capability,[13] including a vehicle control system and a control system software algorithm to be able to land a rocket with the thrust-to-weight ratio of the vehicle greater than one,[34] with closed-loop thrust vector and throttle control[35]
        navigation sensor suite for precision landing[30][36]
        lightweight, deployable landing gear for the booster stage.[10] In May 2013, the design was shown to be a nested, telescoping piston on an A-frame. The total span of the four carbon fiber/aluminum extensible landing legs[37][38] is approximately 18 meters (60 ft), and they weigh less than 2,100 kilograms (4,600 lb); the deployment system uses high-pressure Helium as the working fluid.[39][40]
        hypersonic grid fins were added to the design beginning on the fifth ocean-descent test flight. Arranged in an "X" configuration, the grid fins control the descending rocket's lift vector to enable a much more precise landing location.[41]
        a large floating landing platform in order to test pinpoint landings prior to receiving permission from the US government to bring returning rocket stages into US airspace over land. In the event, SpaceX built the Autonomous spaceport drone ship in 2014,[42] and intends to conduct an initial flight test and landing attempt in January 2015.[43]
        large-surface-area thermal protection system to absorb the heat load of deceleration of the second stage from orbital velocity to terminal velocity[30][44]

about three weeks ago
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SpaceX Rocket Launch Succeeds, But Landing Test Doesn't

frank249 Twitter: Ran out of Hydralic fluid (213 comments)

Elon Musk @elonmusk "Grid fins worked extremely well from hypersonic velocity to subsonic, but ran out of hydraulic fluid right before landing."
"Upcoming flight already has 50% more hydraulic fluid, so should have plenty of margin for landing attempt next month."

about three weeks ago
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SpaceX Rocket Launch Succeeds, But Landing Test Doesn't

frank249 In other words ... (213 comments)

The operation was a success but the patient died.

about three weeks ago
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Rocket Scientist Designs "Flare" Pot That Cooks Food 40% Faster

frank249 Pressure Cookers are faster and the most efficient (204 comments)

When I was in the military and trying to cook frozen food over a camp stove in the Arctic we used pressure cookers. It is fast and heated the food completely without burning the bottom. It is also the most energy-efficient method of cooking Now if they added the flare design to a pressure cooker they might have the best of both designs.

about 7 months ago
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Mars Base Design Competition Open To Non-Scientific Professionals

frank249 Re:Why not underground? (94 comments)

Underground habitats are required not only due to the radiation threat but also due to the cold temperatures. The average temperature is -55C. Surface temperatures may reach a high of about 20 C (293 K; 68 F) at noon, at the equator, and a low of about 153 C (120 K; 243 F) at the poles. Actual temperature measurements at the Viking landers' site range from 17.2 C (256.0 K; 1.0 F) to 107 C (166 K; 161 F). The warmest soil temperature on the Mars surface estimated by the Viking Orbiter was 27 C (300 K; 81 F).

Images from the Thermal Emission Imaging System (THEMIS) aboard NASA's Mars Odyssey orbiter have revealed seven possible cave entrances on the flanks of the volcano Arsia Mons. The caves, named after loved ones of their discoverers, are collectively known as the "seven sisters." Cave entrances measure from 100 m to 252 m wide and they are believed to be at least 73 m to 96 m deep. Because light does not reach the floor of most of the caves, it is possible that they extend much deeper than these lower estimates and widen below the surface. "Dena" is the only exception; its floor is visible and was measured to be 130 m deep. The interiors of these caverns may be protected from micrometeoroids, UV radiation, solar flares and high energy particles that bombard the planet's surface.

about 8 months ago
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SpaceX Resupply Mission To Launch March 30

frank249 Reusable booster rocket (48 comments)

SpaceX,will also achieve a spaceflight first.

After delivering cargo to the International Space Station, the first stage of the Falcon 9 rocket used for the flight will fire its engines for the second time. The burn will allow the rocket to reenter the atmosphere in controlled flight, without breaking up and disintegrating on the way down as most booster rockets do.

After recovering the rocket from the water on Sunday, SpaceX engineers and technicians will study it to determine what it would take to refurbish such a rocket for reuse. SpaceX also has plans to recover and reuse the second stage rocket, but for now, it will recover only the first stage and its nine Merlin engines, which make up the bulk of the cost of the rocket.

about 10 months ago
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Malaysian Flight Disappearance 'Deliberate'

frank249 It could have been just an elaborate heist (436 comments)

They have not released the cargo manifest yet. Who knows, there might have been hundreds of millions of dollars worth of diamonds or art or cash/bearer bonds on board. They would not need more than a 5,000 ft runway to land on if they did not plan to take off again. They could even have pulled a 'Thunderball' landing on the water and then camouflaged the plane with nets. This makes as much or even more sense than many of the other theories. If they never find the plane, it will have been the perfect crime.

about a year ago
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Bradley Manning Wants To Live As a Woman

frank249 Christine Jorgensen (784 comments)

Christine Jorgensen in 1952 was an American who was the first person to become widely known in the United States for having sex reassignment surgery—in this case, male to female. She had served in the Army before going to Sweden for the sex change operation. I think it was Bob Hope who quiped that "Christine Jorgensen was the first guy to go abroad and come back a broad."

about a year and a half ago
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Yes, PlayBook Does Get BlackBerry 10 Update

frank249 Re:QNX and BB10 (90 comments)

Sorry, never crashed.

about 2 years ago
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Yes, PlayBook Does Get BlackBerry 10 Update

frank249 QNX and BB10 (90 comments)

BB10 and the Playbook OS are both based on QNX which is also in 60% of all car infotainment units. Rock solid micro kernal OS that is also used in nuclear plants and medical devices. I have used my Playbook for over two years now and it has new crashed. Apps install without having to reboot. I think many people will be pleasantly surprised with how well BB10 and QNX just works. It also sets the stage for more integration between smartphones, tablets, and car systems.

As for the update to the Playbook, Crackberry.com says that a new version of the Bridge program is in Appworld now which means that the Playbook update to BB10 could be any day now.

about 2 years ago
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Petition For Metric In US Halfway To Requiring Response From the White House

frank249 Gas Prices (1387 comments)

I am convinced that the real reason Trudeau brought the metric system to Canada was that it would be easier to add taxes to the price of gas. Prime Minister Joe Clark was defeated in part based on the fact that he proposed a 17 cent a gallon tax on gas. Trudeau came in and imposed a tax of 10 cents a litre and no body said anything. Even today the price of gas can go up 10 cents over night. I can just imagine the uproar in the US if gas rose 40 cent/gallon over night.

While Canada has been officialy metric for 40 years most people I meet still think in imperial units and I have to explain to my wife what it means when 10 cm of snow is forecast.

about 2 years ago
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US Nuclear Industry Plans "Rescue Wagon" To Avert Meltdowns

frank249 The US military already has almost everything (184 comments)

In the case of a Fukishima type nuclear emergency, the US military already has the most of the equipment need for a quick response such as generators, armoured vehicles, radiation monitors, airlift etc. Under 18 U.S.C. 831, the Attorney General may request that the Secretary of Defense provide emergency assistance if civilian law enforcement is inadequate to address certain types of threats involving the release of nuclear materials. Such assistance may be by any personnel under the authority of the Department of Defense, provided such assistance does not adversely affect U.S. military preparedness.

more than 2 years ago
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Bilingual Kids Show More Creativity

frank249 Intelligence (221 comments)

I found something similar when I was doing my psychology thesis in 1990. I found that my bilingual participants, when compared to uni-lingual participants, had a statistically significant difference in their high school leaving grades, first year university grades and on a test of general mental ability (g). At the time I thought it made sense as the same abilities you use to learn a second language (memory, language skills, cognition) are also measures that an individual needs to learn academic subjects. I did not look at creativity but problem solving is a related ability and is considered a component of g. I think Schmidt and Hunter were right when they said every measure of success is related to g.

more than 2 years ago
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Ask Slashdot: What Are the Implications of Finding the Higgs Boson?

frank249 Re:That's an easy one (683 comments)

Expect the next Star Trek series to explain warp drive as "an artifical inhibition of the Higgs field, allowing conventional matter to transition past light speed."

Star Trek incorrectly explained that by referring to 'inertia dampers' when they should have said 'inertia negation'. Inertia dampers are real devices but they have a completely different purpose.

In Star Trek, Inertia damping/negation is used to counter the effects of sudden acceleration that would impart structural stresses on star ships when suddenly accelerating to or decelerating with the impulse drive, and which would cause passengers to be thrown against walls and crushed by the inertial effects of the vehicle suddenly accelerating or slowing.

Such a device does not need to negate or alter inertia – a similar effect can be achieved by creating a gravitational field opposing the acceleration of the vessel. Such technology, while still nonexistent at the present time and considered unlikely to be achieved in the foreseeable future, is by far more realistic than manipulating inertial mass however maybe they will decide to capitalise on the Higgs discovery and refer to some form of Higgs shielding.

more than 2 years ago
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Ask Slashdot: Instead of a Laptop, a Tiny Computer and Projector?

frank249 A 7" Tablet is a better solution (339 comments)

I used to lug a laptop on business trips but now I can get by with just my Blackberry and Playbook. The Playbook has HDMI out so I can use a big screen TV at the other end to show my presentations and videos using my blackberry as a remote. The Playbook fits in my inside jacket pocket so it is ideal for these kind of trips.

more than 2 years ago
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Low Oxygen Cellular Protein Synthesis Mechanism Discovered

frank249 Give this guy a Nobel (94 comments)

This has the potential to replace chemo therapies with an antibiotic. No more poisoning people to try to make them better. Not to mention the potential to treat stokes and heart disease. Well done!

more than 2 years ago
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Santorum Suspends Presidential Campaign

frank249 Headline tweeted by Jon Stewart (577 comments)

#TDSBreakingNews @RickSantorum suspends presidential campaign. Dibs on the "Romney Licks Santorum" headline.

more than 2 years ago

Submissions

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Discovery offers hope for cancer,heart disease and stroke miricle drugs

frank249 frank249 writes  |  more than 2 years ago

frank249 writes "A team of University of Ottawa researchers has solved the mystery of how our bodies adapt to low-oxygen environments, raising the prospect that life-threatening conditions such as cancer, stroke and heart disease could someday be successfully treated using a simple, antibiotic-like drug.

The team’s findings were published Sunday in Nature, the world’s leading scientific journal. “It’s a tremendously important discovery in understanding how life without oxygen works,” said Dr. Stephen Lee, a professor in the university’s Department of Cellular and Molecular Medicine, whose laboratory did the groundbreaking research.
“These are very basic processes of life,” Lee said. “It’s kind of strange that we discovered this in the 21st century. That tells you there are still basic processes that we just don’t know exist.”"

Link to Original Source
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James Cameron Reveals Sub Design

frank249 frank249 writes  |  more than 4 years ago

frank249 (100528) writes "In January 2010, marking the fiftieth anniversary of the Trieste descent, the X Prize Foundation announced a $10 million prize for the first privately funded craft to make two repeat manned descents to the bottom of Challenger Deep, the deepest surveyed point in the oceans. Now, James Cameron has announced he has commissioned a submarine capable of surviving the tremendous pressures at a depth of seven miles, from which he will not only try for the X prize but also shoot 3D footage that may be incorporated in Avatar’s sequel."
Link to Original Source

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