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Comment: Re:putting OP's bullshit into context (Score 2) 122

by gman003 (#47534723) Attached to: SLS Project Coming Up $400 Million Short

You are factually wrong on several counts.

SpaceX is not working on any version of the CST-100, and their only relation is that the CST-100 is supposedly designed to be compatible with the Falcon 9 launcher (I have reasonable doubt that will happen). They delivered the Dragon cargo capsule, and are working on the manned Dragon V2.

Boeing's CST-100 is orbital, not suborbital. Suborbital means it will not complete a single orbit, like a missile.

Sierra's Dream Chaser is also not suborbital. It also uses many non-NASA technologies, such as the hybrid rocket engines.

You further have many logical errors, the most persistent being the conflation of the launch vehicle with the crew vehicle. SLS, Falcon 9 and Atlas V are launch vehicles. Orion, Dragon, CST-100 and Dream Chaser are crew vehicles.

Orion is NASA's crew vehicle (actually, Lockheed Martin's, but I'll get to that in a bit). It is not suitable for missions beyond the Moon - it has a designed mission length of only three weeks (21 days), which is unsuitable for anything beyond Earth orbit. You are correct that manned deep-space missions will need a super-heavy launch vehicle such as SLS, but Orion itself will not be the crew vehicle.

You also make a mistake in your history. NASA did not produce the Apollo landers or the Saturn V (what I assume you refer to as "what nasa did 30 years ago" or "other NASA firsts"). They set the requirements, and solicited bids from private companies. Just as they're doing now - Orion is being made by Lockheed Martin, the SLS boosters are being made by ATK, Rocketdyne is making the core engines, Boeing is making the upper stage. Really, all NASA is doing is assembling the entire thing, and of course setting the specs and requirements.

Let's look at the Apollo command module, the closest equivalent to Orion/CST-100/Dragon. It was developed by North American Aviation. They merged with Rockwell-Standard during the 1967 to form North American Rockwell, later renamed to Rockwell International, under which name they produced the Space Shuttle orbiter. The Rockwell International space division was sold in 1996 to... Boeing.

Boeing isn't "ripping off from NASA firsts". They're building off work that they did for NASA in the 60s, 70s, 80s and 90s. If anything "NASA" is ripping of them, but I remind you that Lockheed Martin is the one actually building the thing you want to attribute to NASA.

Sierra Nevada is building off SpaceShipOne technology, not any NASA programs. Just because it looks vaguely like the Space Shuttle, that does not mean it actually works the same way. The engines are completely and fundamentally different, as is the aerodynamic design.

And SpaceX is developing everything on their own. The only thing they used from another company is some software/control design from Tesla Motors, a company not coincidentally also owned by Elon Musk. I personally doubt much was even borrowed there except for the basic idea of a single big touchscreen, but I guess it makes for good brand advertising.

tl;dr you're wrong in your terminology, you're wrong in your facts, you're wrong in your logic, and you're wrong in your conclusions.

Comment: Re:SLS and comparing to spacex (Score 1) 122

by gman003 (#47533957) Attached to: SLS Project Coming Up $400 Million Short

The phrase "deep space vehicle" is misleading - it's the payload, not the launcher, that has to be deep-space. However, the SLS is a heavy lift vehicle (70Mg to LEO for the Block I configuration, 130Mg in Block II), while Falcon 9 is a medium lift vehicle (10Mg to LEO). However, the planned Falcon 9 Heavy is also a heavy lift vehicle (53Mg to LEO), and seems much more likely to actually fly.

For comparison on those numbers, the Saturn V was 120Mg, the Space Shuttle was 25Mg, Proton is 20Mg, and Delta IV-H (the most powerful currently-flying launcher) is 23Mg. For a better perspective, to launch the entire ISS, you would need either seven SLS Block Is, four SLS Block IIs, nine Falcon 9 Heavies, or forty-five Falcon 9s.

Comment: Re:... and that's not much. (Score 1) 174

Cs-237 is pretty hot, half life of about 30 yrs. How about

Pu-239 .435 kg
U-235 12500 kg
U-238 80,400 kg.

I am sure these sound scary to most people, though Cs-237 is presumably a significant component of the nuclear release in question.

Of course they sound much worse because you can make nukes out of these and that increases the radiation release rate by many orders of magnitude and that mushroom cloud, etc.

To Americans it's Cesium not Caesium, then again most American don't really know what that it is. And most don't understand radiation either.


Earth In the Midst of Sixth Mass Extinction: the 'Anthropocene Defaunation' 256

Posted by Soulskill
from the i-blame-the-schools dept.
mspohr writes: A special issue of Science magazine devoted to 'Vanishing Fauna' publishes a series of articles about the man-caused extinction of species and the implications for ecosystems and the climate. Quoting: "During the Pleistocene epoch, only tens of thousands of years ago, our planet supported large, spectacular animals. Mammoths, terror birds, giant tortoises, and saber-toothed cats, as well as many less familiar species such as giant ground sloths (some of which reached 7 meters in height) and glyptodonts (which resembled car-sized armadillos), roamed freely. Since then, however, the number and diversity of animal species on Earth have consistently and steadily declined. Today we are left with a relatively depauperate fauna, and we continue to lose animal species to extinction rapidly. Although some debate persists, most of the evidence suggests that humans were responsible for extinction of this Pleistocene fauna, and we continue to drive animal extinctions today through the destruction of wild lands, consumption of animals as a resource or a luxury, and persecution of species we see as threats or competitors." Unfortunately, most of the detail is behind a paywall, but the summary should be enough to get the point across.

Comment: Re:I also measure distance (Score 2) 174

Conveniently, there is an even better comparison. You have to disperse all of the radioactive soil into the air to make a similar comparison. We don't actually pump soil into the air though. We do however burn coal.

Webpage According to the National Council on Radiation Protection and Measurements (NCRP), the average radioactivity per short ton of coal is 17,100 millicuries/4,000,000 tons, or 0.00427 millicuries/ton. This figure can be used to calculate the average expected radioactivity release from coal combustion.

Converting this to metric equates to about 0.174 MBq/ton (metric ton).

WebpageLargest coal plant in America burns 11 millions tons of coal per year.

Now 11,000,000 tons * 0.174 MBq / ton is 1.914e6 MBq -- a bit less than the twice the totally scary 1 trillion Bq

The average coal plant burns coal with around 0.5 trillion Bq / year

Now, not all of the radiation get released into the atmosphere, a lot of it ends up in the ash. But the ash is stored in ponds and left in piles on the ground, so its not a terrible improvement in terms of safe radioactive containment.

Comment: Re:Customer service? (Score 2) 796

kids in strollers

Most strollers are too big to take as carry on.

Strollers are always gate checked. You wheel the stroller down the jetway, take your kids out, and leave it by the door. After everyone has boarded, either the gate agent or the ramp gate crew will take the strollers and any carry-on bags that didn't fit in the overhead bins and stowes them in either the bulk bin(for widebody aircraft) or the front compartment (generally bin 1) in the belly of the plane (this bin is usually the last one filled up in an aircraft). When the aircraft lands that bin is the first one open and the gate crew takes the strollers and leaves them by the door of the plane. The gate checked bags end up at baggage claim or transferred to a connecting flight. But if you are flying with a stroller, you really don't need to bring your every day stroller that seats 4, has 6 cup holders, and has enough storage space you could live out of it for a month on your 5-day vacation to wherever. Those things are a bitch to try to lug up those stairs, especially when you have 4 of them. The small ones that fold up (some even have carrying bags with a shoulder strap) are so much easier and lighter. I have worked as a gate agent and on the ramp on gate crews at the busiest airport in the world, and my advice is this: make things as easy as you can for the crews, and your things are less likely to get damaged. Not out of malice, but because the amount of gate checks gets larger every year and right before departure is the busiest time for the gate crew.

Comment: Re:Good (Score 1) 270

I would settle for nice modular neighborhood-scale TFTR reactors for now. I don't expect to see Mr. Fusion in the years I have left. I don't expect Congress to contribute to either of these either. I might wish they get rid of some unneeded regulations, but I have little hope of this happening either.

United States

Lawrence Krauss: Congress Is Trying To Defund Scientists At Energy Department 270

Posted by samzenpus
from the let-the-science-flow dept.
Lasrick writes Physicist Lawrence Krauss blasts Congress for their passage of the 2015 Energy and Water Appropriations bill that cut funding for renewable energy, sustainable transportation, and energy efficiency, and even worse, had amendments that targeted scientists at the Department of Energy: He writes that this action from the US Congress is worse even than the Australian government's move to cancel their carbon tax, because the action of Congress is far more insidious: "Each (amendment) would, in its own way, specifically prohibit scientists at the Energy Department from doing precisely what Congress should mandate them to do—namely perform the best possible scientific research to illuminate, for policymakers, the likelihood and possible consequences of climate change." Although the bill isn't likely to become law, Krauss is fed up with Congress burying its head in the sand: The fact that those amendments "...could pass a house of Congress, should concern everyone interested in the appropriate support of scientific research as a basis for sound public policy."

The most delightful day after the one on which you buy a cottage in the country is the one on which you resell it. -- J. Brecheux