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Comment Re:We are not rocket scientists, obviously. (Score 2, Informative) 145

You may not be a rocket scientist, but I am, so let me clarify a few things here.

You seem to be confusing ULA and NASA launch efforts here. The Atlas V and Delta IV EELVs are commercial designs. Titan is retired, never to be launched again, and the future (and ultimate feasibility) of Ares I or V remains uncertain. Also, under point 6, Atlas and Atlas-Centaur are the same thing. Atlas refers to the first stage booster and Centaur is the second stage.

Drastically increasing the launch schedule of EELVs would be a tall order, necessitating a great deal of infrastructure development. Where all the money for this, and all these extra payloads you'd like to launch, will come from I have no idea. Right now the gov't is up to its eyeballs in debt, and is rapidly increasing that debt bailing out automakers, banks, and lining congressional districts with cash for votes. I'd love you see the increase in launches just as much as you would (it'd keep me employed), but it's certainly not realistic.

But I have to take issue with the basic premise that seemingly underlies your post here, which is that NASA (or the gov't in general) needs to be the one designing, building, and launching these rockets. Why? Why limit the launch industry to one or two designs with the NASA-approved stamp on them? (Which may or may not be the best vehicles for putting things and/or people into orbit.) Why not promote competition and increase the demand for vehicles in the launch industry by getting NASA out of the launch business altogether. Make NASA a purchaser of rides, not a supplier. The launch industry can then build and fly the designs it wants and let a multitude of designs compete. My dream would be to see another few Space-Xs pop up in the next few years. Thankfully we're actually starting to see a little bit of what I want with the ISS resupply contracts to Space-X and Orbital. I would be even happier, though, if NASA were out of the launch business altogether.

Comment "How Much?" - The Numbers, Calculated (Score 1) 148

Here's what it would take to capture Apophis:

I'm assuming that the capture will take place on the 2029 encounter and that the perigee of any capture orbit is equal to the closest approach distance (this makes the calculations simple enough that I felt like doing them to post on slashdot).

So to capture into a circular orbit would take an instantaneous delta-v of: 4.18455 km/s. (Capturing into a highly elliptic orbit (e=0.9) doesn't reduce the delta-v by all that much (4.13677 km/s instead of 4.18).

Assuming the mass on Wikipedia is right (2.7e10 kg), and using space shuttle main engines (Isp_vacuum = 450 sec), it would take 1.65e10 kg of propellant to achieve the 4.18 km/s delta-v. So, a lot. (More than 1 million Delta IV heavies worth of payload capacity to orbit).

Going to a higher specific impulse form of propulsion, like Ion thrusters with Isp from 3000 to 30000 would take between 3.58e9 kg and 3.81e8 kg of propellant, respectively. Though Ion thrusters are about as far away from applying an instantaneous delta-v as you can get (except maybe solar sails or other neat little things like that).

In conclusion, it would take a hell of a lot of effort to capture Apophis.

Submission + - FCC's New Broadband Plan Prioritizes Competition (pcmag.com)

adeelarshad82 writes: The Federal Communications Commission on released an outline of what might be included in it upcoming national broadband plan, and encouraging competition was a top priority. The FCC statement said "Competition drives innovation and provides consumer choice. Finding ways to better use existing assets, including Universal Service, rights-of-way, spectrum, and others, will be essential to the success of the plan. The limited government funding that is available for broadband would be best used when leverage with the private sector." The stimulus plan provided $7.2 billion in broadband grants and $350 million for a broadband mapping program, but also directed the FCC to deliver a national broadband plan to Congress by February 17, 2010.
NASA

Submission + - SPAM: NASA maps Mercury, set for 2011 orbit extravaganza

coondoggie writes: NASA’s Mercury planet exploration team this week said they have created critical tool for the first orbital observations of the planet – a global map of Mercury that will help scientists pinpoint craters, faults, and other features that will be essential for the space agency’s extensive 2011 mission. That’s when NASA’s satellite MESSENGER (The MErcury Surface, Space ENvironment, GEochemistry, and Ranging, or MESSENGER) will become the first spacecraft to actually orbit Mercury — about 730 times — beaming back pictures and never-before-available pictures and information on the planet.
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The Internet

Submission + - Anthony Watt's responds to Economist (wattsupwiththat.com) 1

cluge writes: Anthony Watts, author of the Watt's Up With That blog has posted an open reply by Willis Eschenbach in response to the Economist. You may recall that the Economist recently had an blog post titled "Scepticism's limits" covered by Slashdot. That post was extremely critical of Mr. Eschenbach and Eschenbach fires back finding errors in logic and fact that undercuts the Economist's arguments. The entire affair is yet another reminder of the power of the Internet and the diminishing bully pulpit of traditional media outlets. 20 years ago Eschenbach would have had a hard time getting a reply out there.
Encryption

Submission + - How to encrypt all internet traffic?

bondiblueos9 writes: Is there a way to anonymize and/or encrypt all of my internet traffic? I am really only concerned about it being so out to at least my cable modem, preferably through it.

I live in an apartment with several people and we all use one cable internet connection through one wireless router (using WPA2) to access the internet. They all depend on me to keep it running. We were having some connectivity/bandwidth issues, and in the process of tracking down the problem I realized that I could use available tools to capture all of their wireless traffic, and in the worst case, I could tap the line from the router to the cable modem to capture all traffic. If I can do it, then that means someone else could, and with the right equipment someone could even tap the cable box outside and grab all my traffic.

I don't mean to be paranoid, but how can I avoid this? I know Tor does this for some applications, but only ones that can be set up to use a proxy, not for all traffic. I had the idea to set up a box between all of my computers and our router, and somehow configure it to redirect all of my traffic through tor, but I do know if this is possible or what tools I need to set up the forwarding. How can I set this up, or what other suggestions/solutions does anyone have?

Comment Re:Summary of Augustine Report (Score 2, Insightful) 144

Sure, we've just got lots of experience with building the Station--and it was a nightmare. Remember, the station largely derives from Freedom studies started as early as 1982. Conceptually, it's almost 30 years old. Even a lot of the hardware is 20+. There were huge overruns, and several major delays due to the Shuttle failing. Doing that with a Mars craft is not an option.

This is exactly my point. You say that the station derives from an old study, and that much of the hardware used is old. Well, any Mars craft could be a blank sheet design taking the lessons learned from ISS and putting them to good use. And as for delays due to the shuttle, you again make my point. If NASA designs another heavy lift vehicle, it will be the only way to get a Mars craft (or pieces thereof) into orbit. What happens if that launch system goes down to a failure? You have the exact same situation you had with the shuttle. However, if you design your Mars craft from the beginning to use existing medium lift, you'll have multiple options to get stuff into orbit (Atlas V, Delta IV, Falcon 9, Ariane, etc).

Finally, while being able to put everything together as one big piece and launch it may simplify some aspects of the design, if we're going to really do worthwhile things in space (colonies, stations, mining) there will have to be piecemeal launches. Habitats and the like will simply need to be too big to be able to launch on a single rocket. Why not start getting really good at putting stuff together in orbit (or on the lunar surface) now? That way, when the expertise is really necessary, we'll have it. We won't have to stop and spend money to develop it.

Comment Re:Summary of Augustine Report (Score 5, Insightful) 144

Heavy lift: A heavy-lift launch capability to low-Earth orbit, combined with the ability to inject heavy payloads away from the Earth, is beneficial to exploration. It will also be useful to the national security space and scientific communities. The Committee reviewed: the Ares family of launchers; Shuttle-derived vehicles; and launchers derived from the Evolved Expendable Launch Vehicle family. Each approach has advantages and disadvantages, trading capability, life-cycle costs, maturity, operational complexity and the "way of doing business" within the program and NASA.

I still don't understand the seeming obsession with heavy lift. Why develop and fly a new huge expensive rocket, putting all your payload eggs in one basket, rather than use a greater number of smaller, cheaper, existing rockets? The more rockets you fly, the more you have to build, and you can begin to take advantage of economies of scale and reduce the dollars per kg cost to orbit. Another advantage is that if your rocket does encounter some calamity, you don't lose your entire (much more expensive than the rocket itself) payload, but rather just a piece of it. Yes, flying your moon/mars/where-ever spacecraft into orbit a piece at a time means that you have to assemble it once you are up there, but that just puts into use all this lovely experience gained building the ISS. So, more light to medium lift: give it a chance.

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