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The more advanced version of this is steering the asteroid into orbit, then mining it.

Do you mean planet Earth orbit ? If yes, it seems that it would require a lot of energy to slow the asteroids down first. I just do not see how it could just be steered into orbit.

Speed is always the same for all objects orbiting Earth at a given altitude without regard for the mass of the object.
Example speeds:
At the Moon altitude 385,000 km: 1 km/s
Geostationary altitude 36,000 km : 3 km/s
Space Station altitude 360 km : 7 km/s
Sea level 0 km: 8 km/s

Asteroid speed is usually around 50 km/s.

http://www.freemars.org/jeff/speed/index.htm

Mach 20 happens to be about orbital velocity. Assuming they can improve the materials somewhat, being able to do that in a plane instead of a rocket would be pretty useful.

Still - it'd be interesting to know if relativistic effects are present.

They always are, the only question is how measurable they are. A rule of thumb I learned in a physics class is the relativistic effects become important at 10% of the speed of light. Of course, 'important' is a relative term.......

To put it into perspective, a satellite travels at 18,000 km/h (or whatever, you can do the math yourself).

http://aeromaster.tripod.com/paper1.htm

http://www.freemars.org/studies/et/

http://www.permanent.com/p-extank.htm

Yeah, I was wondering how a satellite in geosync would be able to get to even an earth-moon L point with no fuel... http://www.freemars.org/l5/aboutl5.html

Let's start a commercial space station. First, connect a module to the ISS. Then, when those idiots plan to burn it down in 2016 via re-entry, disconnect it and start a new space station with that single module.

The Space Shuttle external tanks are the close to the size of a 747 hull and have to make it to orbit with the Shuttle. (Otherwise it would run out of fuel!) Also, they contain hydrogen and O2, which evaporate completely, leaving an empty, non-toxic hull capable of supporting atmospheric pressures. Lots of people have proposed using them as the basis of really large space stations.

http://www.freemars.org/studies/torus/ettoru2.html

What would be involved in changing the inclination of the ISS orbit to match that of the solar system?

Earth is 23.5 degrees from the ecliptic, so in theory (maybe someone else can correct me here) at some point in the year, ISS will be 51.6-23.5=28.1 degrees off of the plane of the ecliptic. ISS orbits at 7.68km/s, so an off-the-cuff calculation would be 2*sin(28.1/2)*7.68km/s = 3.73km/s of delta-V about half the energy of launching it all in the first place. If my assumption is wrong that at some point of the year ISS is only off 28.1 degrees from the ecliptic, and you have to go the full 51.6 degrees, that's 2*sin(51.6/2)*7.68km/s = 6.68km/s - almost as much energy as launching it all. This also assumes that you can do the course correction ballistically - with an ion engine it'd take dozens or hundreds of orbits instead of a partial one, so the math would be completely different. With a 4500m/s exhaust speed chemical engine (f.e. the SSME), 3.73km/s delta-V requires a 2.26 fuel-to-final-mass ratio. If you didn't need to increase the mass of the ISS at all for the rocket engines and fuel tanks, then you'd only need 1070000kg of fuel. A Saturn V can lift 118000kg to low earth orbit, so you'd only need 9-10 successful lifts for the fuel itself. Should be a piece of cake.

If you're going somewhere else with the ISS, then you wouldn't do that change at low earth orbit - higher orbits are slower, so it takes less delta-V up there.

The "iKnife" can actually be used for other things. So now they want you to use something less versatile, such as the "iSpoon" which means you must change your arm service or else you won't be as trendy.

The RIAA attack was more of an exploding van than truck. These guys don't really give a damn.

To launch an projectile into space using this method, requires that the projectile is accelerated from stationary to at least 3 kilometers per second (or 0 to 18,000 kph), all within a few seconds. Probably more to overcome air friction. Gravity provides an acceleration of around 10 metres per second (1 G = 9.8 metres/second per second), so doing this acceleration is equivalent to 300G. To get this acceleration down to the speeds tolerated by electronics, you would have to extend the rail gun all the way out to space.

The following website has a table of orbital velocities, periods, altitudes and lifetimes for various objects currently orbiting the Earth.

Actually, assuming a circular orbit, you have to move faster when you are in a lower orbit, while a higher orbit is slower.

See e.g. http://www.freemars.org/jeff/speed/

...so I'm about 6 light-nanoseconds tall, the screen I'm facing is about one by one and a half light nanoseconds.

A light-second is about a billion feet or 300,000,000m, roughly the same as the distance to the Moon.

86400 seconds in a day, so a light-day is about 26,000,000,000,000m, or 4-5 times the distance to Pluto and Charon, or 170 times as far away as the Sun is from us.

A light year is 9,500,000,000,000 km; and Proxima Centauri (the nearest star) is about 4 of those away, and the Crab nebula is about 4,000 of those from us.

Putting all of that into scale is kind of difficult. Making the Sun as big as a basketball, gives you a barely-visible Earth about 30m away, Jupiter a squash (or golf) ball about 150m away, and pluto an infinitesimal speck over a kilometer out. A light-day from the basketball sun would be a circle 9km across, and if you put the basketball sun in the middle of the US, the next basketball would be in Greenland, northwest Alaska, or Brasil. If you put it in my home town (Perth, Western Australia), you'd be looking at the next basketball in South Africa, southern Russia, or the middle of the Pacific. And the Crab nebula twenty times as far away as the Moon.

The fastest manned spacecraft has travelled at ~40,000km/h, so it would take about 100,000 years (a thousand lifetimes, two and a half thousand generations) to get to the nearest star and 100,000,000 years to get to the Crab. I imagine that even the spectacular views as you approached would somewhat lose their appeal after a few generations.

http://www.freemars.org/studies/magshield/

The problem with putting a telescope (or any other facility, for that matter) at L2, or any of the other Lagrange points, is that their location puts them out of the orbits reachable by the Shuttle for repair purposes. All maintenance would have to be done robotically, and considering the delta-V to return any robotic craft to LEO, it's likely that the service robots would be single-use only.

For those not space-science oriented, the Lagrange points (L1 through L5) are points in space around any two orbiting bodies where their gravity exactly (or nearly so) cancels out; as a result, other objects can be left in stable position at those points. It's even possible to put an object in orbit around a Lagrange point, even though there be no mass there. These are referred to halo orbits. SOHO, the Solar and Heliospheric Observatory is in such an orbit around L1, the postion directly between the Earth and Moon. More information is available online (the last link is a PDF, sorry).

The mean distance between the Earth and moon is 384,400 kilometers. 1,000,000 miles is about 1,609,000 kilometers, so the asteroid will come within about 4.2 earth-moon distances.

Good grief, dont you people know how to use a search engine to do a little research before you post?

Freemars - Gravitational interaction (tides on the Earth caused by the Moon) transfers kinetic energy from Earth to the Moon, slowing Earth's rotation and raising the Moon's orbit, currently at a rate of 3.8 centimeters per year.

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Still, it's a great idea, and I wish someone could prove me wrong.

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