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Comment Congestion (Score 1) 239

No one seems to have picked up the one thing that city hall seems to be worried about, which is real, which is congestion.
In a free market the streets would be extremely full of taxis (broadly defined) hanging around hoping to be closest at hand when someone needs transport, to the point where this is a significant nuisance for everyone else. It is for this reason (at least originally) that most cities limit the number of vehicles allowed to pick up
"street hail" custom. In London (and probably elsewhere in the UK) there is a separate category of vehicles which are allowed to do pre-booked runs (originally you'd have been booking by phone from a landline, so it was really quite different). There is, apparently a phenomenon of professional Uber drivers hanging around near likely pickup points (stations, airports) to the point where it does or might cause congestion, so the same rationale as applied to taxis would argue for somehow restricting this (eg the 5 minute rule would make it more sensible to be parked rather than cruising).

An alternative solution though would be to increase the congestion charge (a generic daily charge for using central London roads) and extend its reach until congestion dropped to acceptable levels. The money could be used to reduce other taxes. Even more extremely, they could just decide the number of vehicles they like in central London and auction off that many daily (or hourly) tickets instead of having a flat charge.

Comment Re:Older than Big Bang galaxies (Score 1) 63

This is true. However, within the next 10 years I suspect they will start finding galaxies older than the big bang.

You can, of course, suspect what you like, but out of curiousity why? What we see is remarkably consistent with a big bang. The very old galaxies we
see are small and poorly structured, as we would expect, the CMB is still there, etc.

Comment Re:how low can it go? (Score 1) 45

Clearly it is at a good height now for imaging the whole surface, but as there is no atmosphere could it get down to a mountain scraping orbit? Just high enough to get round the lumps and bumps and variability in the roundness of the object? Would that enable it to image things at a really small pixel size?

Not really. The lower your orbit, the faster your spacecraft has to fly to maintain that orbit.

True, but in zero gee and with no atmosphere that isn't really a problem. It would take some time and reaction mass to get into such a low orbit. The problem is the uneven gravity field -- see my other post,

Comment Re:how low can it go? (Score 4, Informative) 45

as there is no atmosphere could it get down to a mountain scraping orbit? Just high enough to get round the lumps and bumps and variability in the roundness of the object? Would that enable it to image things at a really small pixel size?

Apart from the question of what range the instruments were designed tooperaqte best at, the other problem is the unevenness of Ceres gravity. They are mapping that now, but it's unlikely the mass of Ceres is perfectly symmetrically arranged, so the gravity will be uneven. Those unevennesses distort the orbit and cause it to change over time. If you're 300 km away that's not a big problem, except that you occasionally have to use up some reaction mass to get back where you want to be. At 10km it would probabl;y be disasterous.

For the same reason it's very hard to keep a probe in a stable orbit less than 100km or so above Earth's moon.

Comment Re:Storage (Score 2) 327

Demand is generally higher during the day, so at least for a while this will mean a less variable demand on other supplies, not more.

Moving water up hills (or not letting it down -- letting hydro reservoirs fill up) is quite a good storage option on this scale.

Demand can also be shifted to some extent. You can within certain limits, choose when to cool a refrigerated warehouse, or charge an electric car. I imagine tarifs that make electricity cheap in the few hours after dawn and expensive in the few hours after sunset, for instance.

For the last awkward gaps, methane plant can be built that is designed to switch on and off quickly and run at a relatively low duty cycle. If you're that desperate you can make the methane from CO2 (or food waste).

I've seen reports significant gains in efficiency of making diesel from CO2 and electricity, to the point where that may become a storage option.

Comment Re:Lowcost? (Score 1) 75

Tracking a few thousand active satellites is trivial, especially as they are radio transmitters and are probably telling their base stations where they are pretty often to allow groundstations to aim their beams.

Since they are in LEO they will not last long once they are out of use. Even if they all failed catastrophically it would be a problem for a few years at most.

Comment Re:Only if it works (Score 1) 337

Small ones are, for basically the same reason that small steam engines were hard to develop initially -- too much surface to leak heat compared to the volume of interior. Big ones are expensive and technical to build, but there is currently no evidence that they won't be energy-positive. This article reports some theoretical engineering progress that might move the trade-offs usefully.

Comment Re:Flyby or Orbt? (Score 1) 79

There was some discussion of using what is eupemistically called "lithobraking" to put a probe down on, or more accurately in, Pluto's surface. Apparantly you really can make a probe that has a reasonable chance of still sending back useful science after hitting Pluto at 15 km/s or so.

Comment Re:Now what? (Score 1) 242

I think the Dutch government have something similar to the UK Human Rights Act. This makes the rights defined in the European Convention on Human Rights enforceable in the Dutch courts. The parliament could change that law but unless it does the courts can instruct the executive in how to apply the law so as to maintain those rights.

A quick google also suggests that international treaties which the Netherlands has ratified may be directly enforcable in the Dutch courts without needing additional laws to be passed implementing them (as would be the case in the UK). This seems to be a confused area, but it sounds like the court is taking this line.

I like work; it fascinates me; I can sit and look at it for hours.