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Comment Size matters! (Score 1) 185

Space junk comes in so many sizes. Satellites and space stations have shielding to protect themselves from the smallest junk pieces. They can also make slight shifts in their orbits in order to avoid collisions with the pieces of junk that can be tracked, down to about 4 inches.
But the junk between about 0.5 -4 inches is too small to be tracked, and cannot be effectively shielded against. They have to rely on luck...
Junk in low earth orbit is also more likely to be traveling in all sorts of different orbits (inclination, eccentricity and precession rates), so a satellite could be hit by junk pieces coming from several different directions at once!

Comment Bitmeter (Score 1) 319

Bitmeter is very nice. I use it on my gateway computer to measure the total in/out traffic for the household. It shows usage at hourly, daily and monthly intervals.

It seems to me that if the ISP is going to impose these caps they would be obligated to provide such tools for their customers to monitor their own usage.

Comment Runaway Admissions Cycle (Score 1) 256

This is getting ridiculous!
High school seniors are now being encouraged to submit applications to at least 8-10 colleges, since the acceptance rates have been going down. The acceptance rates have gone down since the colleges are getting more applications. Where will this end?
Colleges have the unenviable task of trying to figure out how many of the applying students to admit, while trying to factor in how many of those will actually accept. Many of those students may not really want to attend there, but applied there out of fear of not getting in their first choice college. The ones getting rejected may actually want to go to that college, but are shut out due to the sheer numbers of other applications. The lucky ones may end up on a wait list, but being in limbo like that is hell.
Some college applications actually ask how many other colleges (and sometimes ask for names too) are being applied to by the student.
Perhaps they will start asking them to rank them too.

Comment Certainly don't want to do that today... (Score 5, Interesting) 237

Those radiation belts are composed of trapped electron and proton particles, bouncing back and forth along those magnetic field lines. There are several numerical models that predict what the population of these particles based on their location, and general behavior under different conditions (solar cycle variations, solar flares, etc).
Anyone building a satellite will use those models to determine what levels of radiation levels the satellite will encounter along its orbit, and add on the appropriate level of shielding to protect the electronics.
A nuclear bomb will never be able to alter the shape of the belts. All it will do is add a spectacular amount of electron and proton particles to the radiation belt, potentially frying the electronics of most of the low to medium orbit satellite (geosynchronous ones will probably be ok). Depending on the size of the bomb, the radiation belt may take weeks or even months to return to a 'natural' state.
There are some experiments in the works to 'tweak' the radiation belts by beaming low frequency EM waves, to change the energy of the existing particle populations. In theory, that will enable some of the particles to become 'untrapped', thereby reducing the overall population.

Comment Nice idea, but it will never work. (Score 1) 221

IANARS (I am not a rocket scientist), but have done much work-related research in the space junk population calculations.

Many other posts have already stated that most of the pieces of junk will never be able to be captured with way, due to small size and/or relative velocity issues.

We will never be able to effectively use space travel until we solve this. If the space junk population continues to increase, it is liable to set off a collision cascade effect (Kessler syndrome) - errant junk colliding with larger pieces to create more small pieces to collide with other objects, and so on. Kinda like a nuclear reactor, or the analogous 'room full of ping-pong-loaded mouse traps' demonstration... Space travel could be even more dangerous when this happens.

For the time being, we can steer our craft around the larger pieces of junk that we can track, put shielding on our craft to protect us from the small pieces. But there's a size range of pieces that are too small to be tracked, but too large to be effectively shielded.

The solution to this problem has to start at the top - take out the biggest pieces of space junk - that will reduce the chance of the collision cascade effect. A fleet of mini space tugs, each programed to safely de-orbit a specific piece of junk, should be able to put a significant dent in the problem. The use of lasers would complement the work. Hopefully, as our technology and experience increase with this, we'll be able to remove the smaller pieces as effectively.

Submission + - Post-Valentine's Day Poll

psychogre writes: Poll Idea for post-Valentine's Day :

What is the longest romantic relationship you have had with another person?

* a furtive glance
* a longing look
* until I opened my mouth
* half a date
* a whole date
* one week
* 1 month
* 6 months
* 1 year
* 5 years
* 10 years
* 20 years +
* as long as the dream lasts

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