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Comment Re:Repeater/router stations (Score 3, Insightful) 109

Actually, the DSN model would work fine for a manned mission to Mars. You're never actually behind the Sun (well it might be possible, but it would be for less than a day). There is an issue where the Sun-Earth-Probe angle drops down to around 3-degrees (so, close to behind the sun), because of radio interference from the sun, but thats about a week long period that you could probably get away with. The biggest cause of comm issues at Mars is Mars itself. Fortunately, all orbiters have an Electra package that allows them to act as relays for each other and for surface assets.

Relay systems are actually more useful in the Earth-moon system at this point. A Lagrange point relay would be important for a far-side base on the moon, or a lander on that side. Earth orbit is where the biggest need for relays is, because the Earth is always in the way for LEO assets. Thats why we have TDRSS.

The biggest issue right now is simply the load on the DSN. Its underfunded and its hard to get enough time on it.

Comment Re:why not a simple rocket (Score 1) 153

Landing on a tumbling small body is not something you 'simply' do. Doing it to apply significant thrust is even harder due to center-of-gravity issues.

A better way to have the same effect is to use a gravity tractor approach. By hovering away from the asteroid, you can use the gravitational attraction of the spacecraft on the asteroid in the same way. Since you'd need to use low thrust engines to get a significant amount of force over a reasonable time frame, the fact that the gravity tractor limits the amount of force you can apply is not too much of a constraint.

However, the advantage of this painting method (we studied something similar in graduate school, the sticking point is how to get it to adhere to the surface) is that it requires the spacecraft to perform a one-time operation, but the effect is permanent, and over 50 or 100 years it could push an earth-crossing asteroid onto an orbit that was perfectly safe. If you could send one mission out to take care of a few of the more risky ones you could do it fairly inexpensively, assuming you figure out the material issues.

Comment Re:Better off using marbles (Score 1) 153

The immediate transfer of kinetic energy is a small effect. The larger effect is a change in the albedo, particularly on a rotating asteroid, because that allows you to affect how the Yarkovsky effect is applied.

When you change the Yarkovsky effect, it changes a force that is applied along the velocity direction, causing it to speed up or slow down: this is the most effective way to change the orbit in a way to avoid an impact. Because the force is applied for a very long period of time, it can avoid both the immediate impact risk and cause the object to move to an orbit that is permanently safe -- however, thats a 50 or 100 year effect.

Of course this all applies to small asteroids. For a large one you're still left with with gravity tractors/explosives/etc.

Comment Re:What is private? (Score 2) 164

You're right that the nomenclature is confusing. "Private" in this case means that the NASA is attempting to kickstart a competitive market by putting itself out there as a guaranteed customer -- very similarly to how the USPS helped jump-start the commercial airline industry by guaranteeing itself as a customer to use airmail. In the end, an SLS vehicle will be owned by NASA, while a Dragon capsule or Dream Chaser vehicle will be owned by their respective companies, and are free to sell rides to anyone else (admittedly the non-US-government market is unproven).

The problem with the GOP platform is that they support NASA building their own competitor to the commercial options, effectively strangling the goal of COTS/CCDEV. As the supposed party of free markets, the GOP should recognize this and be clamoring to get the government out of LEO transportation -- the SLS program is such a ridiculous example of government waste it calls into question the party's dedication to concepts of deficit reduction and free markets.

Comment Re:Bittersweet (Score 5, Insightful) 184

You're correct, 'commercial' is a bit of an a awkward term here. However, there are two reasons this is a big change from past contracting methods for developing spacecraft that the government uses:

1. There is competition. The reason (well regulated) markets are efficient is not profit motive, but competition. This is why Sen. Wolfe's proposal to select only one winner was so antithetical to the purpose of the program.

2. The government is buying rides, not buying vehicles. The companies that produce Dragon, CST-100, and DreamChaser are free to sell rides to anyone arms control treaties allow. There is some mile-stone based development money right now, but thats only because it is in NASA's interest to stimulate and accelerate this market rather than build competitive vehicles.

While this won't be truly commercial until a company can do well without a government customer, this is a step in the right direction, and nothing to sneeze at.

Comment Re:Correct me if I'm wrong... (Score 4, Interesting) 90

You're assuming its an investment, not a donation. A decent planetary science mission will cost $500M in NASA dollars. Take out federal procurement and the endemic requirement growth and you can imagine a worthwhile mission for $300M.

As Ed Lu (B612 Foundation CEO who is launching the Sentinel mission) pointed out in a recent talk, this is an equivalent amount to a new wing in an art museum -- not insignificant, but not impossible. The conversation he had with a fundraiser went like this:
    Fundraiser: "So you can really launch something into an orbit around the sun???"
    Ed Lu: "Of course. You can really raise $300M in donations???"

A science mission won't return a monetary investment, and no one should expect it to. This doesn't mean that you can't fund it as you would other public works projects.

Comment Re:Query (Score 4, Insightful) 57

Actual Answer: Leave the regulatory regime completely undefined so that no one will risk launching for fear of over-restrictive 'DO SOMETHING!' regulations killing their business model after they've already settled on an approach.

Its far better to define reasonable regulations right now than wait for poorly thought out ones to be implemented later when it becomes clear they're necessary.

Also, the FAA AST (Office of Commercial Space) folks are very supportive of getting a real industry off the ground. They're space enthusiasts, not charicatures of empire-building bureacrats.

Comment Re:Mixed blessings (Score 1) 217

The FAA Office of Commercial Space (AST, don't ask me how the acronym and the name line up...) is attempting to do just that.

Its really a quite nice arrangement, because the FAA has been working on this since when the concept of private space flight had an extremely large 'giggle factor', and they have been working back and forth with the commercial providers to ensure that the regulations make sense and won't be too restrictive, while still maintaining safety.

Plus everyone I've met from AST has been really friendly.

Comment Re:argh, you dumb fucks (Score 3, Informative) 149

Not quite though. The difference between traditional government contracting and the current COTS/CCDev approach is subtle but important.

Development of all NASA vehicles (past the initial architecture studies) are done largely by private companies such as Lockheed Martin. However, the contracts for doing so are basically that the contractor is building exactly what the government asked of them, and they will be paid whatever the development costs with an additional guaranteed profit on top of it -- thus the name 'cost-plus contracting.' While this is necessary for high-risk, low-reward development, its something to avoid whenever possible since it combines the lack of competition of monopolistic or governmental development with the desire of corporations to increase their profits -- this is clearly a recipe for rising costs.

COTS and CCDev operate on a model more like how you and I buy things. The companies contracted this way are being paid a fixed amount and expected to produce. Because this is an expensive field, some of the money is being provided up front (and at certain milestones) in order to speed up development, but even if the final product ends up costing more than NASA pays, we the taxpayer don't pay any extra -- the companies involved will still finish it though because otherwise they don't get paid (assuming they're far enough along at the time of realizing they're going to be over-budget that its still cheaper to finish). After development, it will be a purely pay for service contract, different from getting a Super Shuttle from the airport only in scale. By having multiple competitors and fixed-price contracts, costs and quality will be controlled.

So yes, all previously development was 'commercial' as well. As someone involved in pushing for these "New Space" approaches, I really wish we had picked a better name for it, because the difference is subtle but importantly. Personally, I really like the name COTS because it implies the true goal: to make purchasing flights to orbit as simple as pulling the best competitor for the particular mission 'off the shelf' rather than requesting cost-plus custom solutions.

Comment Re:I find this curious (Score 1) 258

The problem isn't the NASA budget as a whole, which as you point out is doing all right by historical standards, particularly given the larger budget situation within the government. The talk of cuts has more to do with allocations within NASA.

Specifically, SLS (the new heavy-lift to nowhere rocket) and James Webb Space Telescope are eating everyone else's lunch. Planetary Science and Commercial Cargo/Crew development, along with Earth Science, are the programs suffering from this.

SLS is the real tragedy, because its 2+ billion/year funding is so senseless. NASA can't build it to meet the congress-specified requirements within the congress-specified funding, and doesn't know what they would do with it if they could build it -- it would be capable of launching very rarely and at an excessive cost. The only people who want the thing built are the lawmakers, thus its nickname, the Senate Launch System. Amusingly, its been described as a 'backup' to commercial development, which they want to cut from $800M/year down to $450M/year to pay for it, and require NASA to pick a winner now (which the government is notoriously bad at). The money is a complete waste because it will certainly be cancelled by a new congress long before it ever gets anywhere near being built.

The other killer thats causing budget cuts across the science division is James Webb, the next big space telescope. This one isn't quite as depressing because at least its likely to be useful when completed, but its been incredibly mismanaged as the costs have ballooned from less than $2B to more than $8B. In order to keep it alive, much of the rest of the science division has suffered.

Ultimately, when they speak of 'budget cuts' for NASA, its cuts for internal programs, and the blame can be laid largely on micro-management by Congress.

Comment Re:Surprisingly poor quality images (Score 1) 42

'Edge of space' is well below the Van Allen belts. The cost of space-electronics comes from having to harden them against radiation. Cosmic rays can and will cause bits to flip at random, so you need to harden them against all but the most energetic particles -- something in the upper atmosphere (which is where these high-altitude balloon cameras are), is protected by the same magnetic fields that protect us on the ground.

The other option is to stick your electronics in a lead box (see Juno), but a camera won't work very well that way.

And if imaging were the primary purpose of the mission (such as on LRO), then the camera would be much better, and much more expensive. GRAIL is intended to map the gravity of the moon, and the MoonKAMs are attached for the sake of reaching out to schoolchildren, not for science, since LRO is doing a fine job of that, so they went with something cheaper.

Comment Re:Aptly named "Dragon" (Score 2) 84

Look at the sequence of the failures: First 3 failures with all the ones after those being successful. This means that they learned the appropriate lessons from the early failures.

While the small number of flights is still too low to make me confident in their safety, I wouldn't say the early failures are a particular cause for concern. Its not like Orbital Sciences where the most recent launches have dumped their payloads in the ocean.

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