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Comment: Major Problem (Score 1) 254 254

Yes a Colony on Venus would have water and sunlight but they would still be at the bottom of a gravity well(same for Mars). It would make more sense to establish a colony in space where you could find water and minerals in asteroids. Supply ships would not need to overcome gravity and return flights could take back precious minerals that would help fund the expense.

Comment: Re:Too bad they couldn't test the escape system (Score 2) 316 316

I read that the Dragon escape thrusters can be used anytime prior to orbit since they are built in and not jettisoned like the old escape tower rockets. Likely not installed in the cargo version but perhaps they should be precisely for this type of event. It would have been useful to save the Dragon capsule and the cargo.

Comment: List of lost Cargo (Score 2) 316 316

There is a listing and pics of the lost cargo here.

The Dragon SpX-7 mission was to deliver supplies to the International Space Station and return cargo to Earth. Dragon remains the only visiting vehicle of ISS that can return a significant mass of cargo to the ground, aside from the crewed Soyuz spacecraft that can ferry a few dozen Kilograms of return items back to Earth along with its three crew members. The SpX-7 mission will carry 1,952 Kilograms of cargo to the Space Station and return 675 Kilograms to Earth at the conclusion of its five-week mission.

Crew Supplies - 676kg
Systems Hardware - 461kg
Science Cargo - 529kg
Computer Resources - 35kg
EVA Equipment - 166kg
External Payloads - 526kg

Interesting to note that part of the science cargo was the Meteor study. The Meteor study, going by the full name of ‘Meteor Composition Determination,’ was to be the first of its kind to be deployed in space, solely focused on the analysis of meteors entering Earth’s atmosphere and pin-pointing their composition through their optical emissions when burning up in the atmosphere. The original Meteor hardware was expected to arrive aboard the International Space Station in October 2014 on the Cygnus Orb-3 resupply craft that unfortunately was lost in a launch failure of its Antares launch vehicle just seconds after lifting off. Coincidence or someone really does not want this study to go ahead.

Comment: Re:*sigh* (Score 1) 72 72

'It's virtually impossible to determine how much recovery will bring down the costs of launch because we don't know how much it will cost to refurbish the recovered vehicle. Certainly it will be cheaper than building a new one, but how much cheaper is impossible to predict... especially in the beginning with zero experience.'

I am going by what SpaceX themselves have estimated.Reusable Falcon 9 Would Cost $5 to $7 Million Per Launch. 13,000kg to LEO at that price is $500/kg or $209/lb. Falcon Heavy's payload is 53,000 kgs.

SpaceX has stated that in order to achieve the full economic benefit of the reusable technology, it is necessary that the reuse be both rapid and complete—without the long and costly refurbishment period or partially reusable design that plagued earlier attempts at reusable launch vehicles. SpaceX has been explicit that the "huge potential to open up space flight" is dependent on achieving both complete and rapid reusability. CEO Musk has publicly stated that success with the technology development effort could reduce "the cost of spaceflight by a factor of 100" because the cost of the propellant/oxidizer on the Falcon 9 is only 0.3 percent of the total cost of the vehicle.

And yes they did learn much from the shuttle program. They plan to inspect, refuel and relaunch in a matter of days so those costs will be minimal. Remember the boosters are not going into space nor the stress of reentry.

Comment: Falcon Heavy will land 3 boosters per mission (Score 4, Interesting) 72 72

Check out this video of Falcon Heavy. They plan to land and reuse all 3 boosters at the landing site they have leased at the Kennedy Space Centre. Saving 9 engines from a Falcon 9 is a considerable savings but saving all 27 engines from a Falcon Heavy launch would bring the cost per kg down to perhaps $100.

Comment: Not enough gravity to hold the atmosphere (Score 4, Interesting) 136 136

The surface gravity on Mars is 38% of that on Earth. The lower gravity of Mars requires 2.6 times Earth’s column airmass to obtain 100 kPa pressure at the surface. Mars also lacks a magnetosphere, which poses challenges for mitigating solar radiation and retaining atmosphere. The lack of a magnetosphere is thought to be one reason for Mars's thin atmosphere. Solar-wind-induced ejection of Martian atmospheric atoms has been detected by Mars-orbiting probes. Earth abounds with water because its ionosphere is permeated with a magnetosphere. The hydrogen ions present in its ionosphere move very fast due to their small mass, but they cannot escape to outer space because their trajectories are deflected by the magnetic field. Venus has a dense atmosphere, but only traces of water vapor (20 ppm) because it has no magnetic field. The Martian atmosphere also loses water to space. Earth's ozone layer provides additional protection. Ultraviolet light is blocked before it can dissociate water into hydrogen and oxygen. Because little water vapor rises above the troposphere and the ozone layer is in the upper stratosphere, little water is dissociated into hydrogen and oxygen

Comment: Convert to PDFs (Score 1) 203 203

A handy program is ABC Amber. It can convert a variety of email archives(outlook, BlackBerry, Groupwise etc) into a number of different formats including HTML and PDFs. The PDF feature is nice as it links to the attachments. It allows bulk operations and seems to be very fast.

+ - Breakthough makes Transparent Aluminum affordable

frank249 writes: In the Star Trek universe, transparent aluminum is used in various fittings in starships, including exterior ship portals and windows. In real life, Aluminium oxynitride is a form of ceramic whose properties are similar to those of the fictional substance seen in Star Trek. It has a hardness of 7.7 Mohs and was patented in 1980, and has military applications as bullet-resistant armour, but is too expensive for widespread use.

Engadget reports that there has been a major breakthrough in materials science. After decades of research and development, the US Naval Research Laboratory has created a transparent, bulletproof material that can be molded into virtually any shape. This material, known as Spinel (magnesium aluminate), is made from a synthetic powdered clay that is heated and pressed under vacuum into transparent sheets. Spinel weighs just a fraction of a modern bulletproof pane.

Comment: Re:Intriguing, but landing at launch site? (Score 1) 53 53

Apparently the stage separation at an altitude of 50 miles, is only 16 miles from the launch point. From the environmental assessment:
"Currently, the Falcon 9 first stage drops by parachute approximately 500 nautical miles downrange into the Atlantic Ocean, east of and well beyond the east coast of Florida, and is recovered by a salvage ship . It is anticipated that the stage would return to the landing pad within approximately 10 minutes after lift-off. Preliminary trajectory analysis indicates that a point directly beneath the vehicle at stage separation falls approximately 16 nautical miles from the launch site."

Comment: Re:Reinventing the wheel -- Am I missing something (Score 1) 213 213

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]

Comment: Twitter: Ran out of Hydralic fluid (Score 5, Informative) 213 213

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."

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