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Comment Re:misleading title (what else) (Score 2) 130

Nah. If that crater was caused by a small meteorite it wasn't travelling at a few hundred miles an hour. If the ejecta had sufficient energy to maim and kill, either the meteorite has transferred momentum from it's great mass or great velocity (or a useful combination of both). Let's try and bury the old Slashdot shibboleth about how meteorites just fall to earth like stones from the top of the Empire State building. More than willing to hear from somebody better equipped.

A meteorite entering at as near damn vertical to the atmosphere will take less than 10 seconds to plough through the last 60 miles (100k), if you fully discount deceleration just for the moment (not going all Calculus). If it starts in at a reasonable 25000mph, roughly 40000km/h, (on the low side for these things) that pissy bit of atmospheric braking has a job to do. a = v-u/t . That looks like a deceleration of 4X10^6 m/sec/sec to me. It's not an even deceleration of course because there isn't a whole lot of atmospheric density until the last 20k. Now the good old gravity thing adds 9.0 m/sec/sec to the acceleration side of the equation making it that bit harder to slow this thing down to a few m/sec constant velocity at some reasonable undefined height above ground. The outcome required would be a "survivor" saying "who threw that" vs a "bystander" saying 'did that guy just blow up"?

It is reasonable to argue that ablation removes momentum so we probably can't get any further until we can find useful figures that allow a back of hand calculation for loss of mass. I suppose we'd need to define a standard mass/velocity (momentum) required at the Earth's surface to maim somebody and go backward from there.
The terminal velocity argument needs a lot more definition of its parameters IMHO.

Some sort of committee is needed to eventually, after much debate, to lay down the basis for further investigation.

Small has to be defined. (Smaller than Wolf Creek impactor isn't sufficient)
Angle of entry to the atmosphere has to be defined. ("Any angle that delivers my proposed outcome" kind of lacks force of argument).

If this thing is to be funded I suspect it is necessary to investigate how this type of incident, something, something, climate change.

You know, this guy has given his given his life for science and saved us a whole lot of future bother. Next time somebody states that a meteorite won't kill you - just post the picture of the hole.

Comment Re: Backing down not up? (Score 1) 242

Yeah, I coulda/shoulda been more specific about those factors. Because of their variance you need to be adaptive about how far from the water you stop. It's not about the car it's about having the boat and trailer in the correct depth (and angle) to launch it. Too deep and the trailer gets drowned and the boat and trailer can drift apart. Too shallow and the boat don't float - just gets damaged.

It's not a fixed distance from the edge so it varies between boats, ramps and tides.

At a busy ramp there is immense peer pressure (up to and including threats of violence) if you aren't efficient and tidy with your launch.
The problems (like any) may indeed be broken down and addressed one by one - but the cost of the time and effort to produce a solution for any and every launch seems at a minimum, expensive.

There would be other unique driving experiences where an automated car fails.
For office potatoes commuting on a drizzly day in Seattle it might be a dream come true.
Can't see it being popular with motorists who want to do anything other than drone travel a to b though.

Comment Backing down not up? (Score 1) 242

Give me a call when one of these clever cars can back my boat down a crowded ramp. All ramps have different slope angles and water levels change with the tides so every launch requires a different solution of where to stop.
From what I've seen of self-driving mowers and robot vacuum cleaners in action I'm not enthused about the level of thought that goes into problem solving for these things.
Quite happy to see millions of these things in New York and Los Angeles though, and from Youtube footage, around Moscow would be a hoot too.

Comment Re:Obviously (Score 2) 68

Yes, there were no troops left in Texas, California, Panama, Philipines, Japan, China, Guam, Puerto Rico, Cuba, Japan (again) Guam, Germany, United Kingdom, Australia, Saudi Arabia, Kuwait, Iraq, Afghanistan.......Unless of course the people there really really begged for those troops to stay.

It's all point of view. There's plenty of Russians that think that annexing the Crimea was a just and caring move to guarantee the longer term safety of the people. Peace on Earth and goodwill to all Russian speaking minorities that love freedom etc..

Everybody means well in these things...don't they?

Comment Re:A stalker with billiard skills (Score 1) 244

That's from "Saturday Nights Alright for Fighting" not "Benny and the Jets"

She's got electric boots and mohair suits, you know I read it in a magazine, ohh B B B Bennie and the Jets.

Get about as oiled as a diesel train, Gonna set this dance alight, 'Cause Saturday night's the night I like

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