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Comment Re:Even if it does explode with the full brightnes (Score 1) 312

Betelgeuse has a declination of 7 24.5' which barely varies at all, meaning it's visible from the North Pole all the way down to 75 South of the equator at least at one point during any 24 hour period. Most populated areas will get to see it at least 30 degrees above the horizon (the closer you are to 7 North, the higher up in the sky you'll see it, and the longer it will be visible each day).

So if it happens, you can watch it at home unless you live on Antarctica. If you have preferences as to seeing it at sunset, midnight, sunrise or midday, you might need to travel East or West.

Comment Re:The meaning of random (Score 3, Funny) 654

Not really. Many goods have a density higher than that of seawater. The addition of extra fresh water from melting ice caps will help reduce the density of seawater. This will increase the range of products that can be thrown overboard to be delivered to underwater wastelands.

Also, higher sea levels will make it easier for bigger ships to sail right into the heart of sunken cities. This will further increase the efficiency of shipping, and reduce the need for secondary transport systems.

Now please, stop crashing the "glass half full"-party.

Comment Re:The meaning of random (Score 2) 654

I love how some people can be so determined in saying humanity has hardly any impact on our planet. Consider the changes in human lifestyle over the last 100 years. Consider population growth. Consider consumption or natural resources. Consider how much of the Earth is changed by human development. Consider the combined effect of those, and then tell me it's a good idea to keep doing what we're doing.

It feels to me like some people are giving in to the fact that we did in fact evolve from monkeys, and they've found another noble cause to hang on to.

Comment Re:The meaning of random (Score 5, Insightful) 654

How can you be so sure that there is little we can do to stop it? The fact that we can't prove that we're responsible for global warming doesn't prove that we're not. And if you do a proper risk assessment, like this guy does in his series of videos that are very much worth viewing despite his silly hats, you'll find that the smart thing to do is to try and do something about it.

Your line of thought sounds like "the Earth is going to hell but we might not be responsible so let's just see where this goes". Consider the possibility that we are responsible, and/or (they don't even have to be connected) the possibility that we can do something about it.

Comment Re:Watts (Score 1) 868

As long as you're not the one doing the converting, someone will try to squeeze you for another joule.

It is a valid thought experiment, though. It raises some interesting questions. I think the main danger would be the practical application of fusion power. In your economy of energy credits, fusion power would cause hyperinflation and crash the worldwide economy. In the world as we know it, it would probably only crash the oil and gas markets, which have no real long term future anyway.

Comment Re:Watts (Score 1) 868

Trading 2kW for 1kW or less is being done on a massive scale everywhere in the world. Thermal power stations convert heat to electrical energy with an efficiency of 33-50%, meaning they're trading 2kW of heat for (at best) 1kW of electrical energy.

Side note: you should be talking about either watt-hours or joules as a unit of energy. Watt is a unit of power, or energy per unit of time.

Comment Not the first with this idea (Score 3, Insightful) 431

In the '90s, a feasibility study was done in the Netherlands for an Underground Logistics System. It involved little carts that could drive themselves, and carry a variety of cargo pallets. The idea was to connect Amsterdam's Schiphol airport to a nearby train station and a flower market. They never built it because the financial risks were too big.

More recently, a Belgian engineering firm proposed an Underground Container Mover for the port of Antwerp, which is basically a large underground conveyor belt for containers. It would run in a circle connecting container terminals with other terminals and highways on the other side of the river. This could remove a lot of trucks from the busy highways, especially the tunnels.

The basic idea is that as ground is becoming more and more rare, we shouldn't waste it on cargo transport. Moving most of it underground makes a lot of sense. And we've actually managed to move a lot of it (up to 90% in some areas) underground already, in terms of tonne-miles of goods transported. Just think of drinkable water, gas and sewage, but also oil and a lot of chemicals in industrial zones. Pipelines are transporting more than most people can imagine, and they're great. Trying to move boxed goods in a similar fashion is the logical next step, there are just a few problems we haven't figured out yet.

Comment Re:Proportions seem to be missed (Score 2, Informative) 595

You can't disconnect fuel efficiency from pollution efficiency, because you can't disconnect internal combustion engines from exhaust gases.

ICEs need something to burn, and it doesn't matter much what that something is. It can be carbon, hydrogen, sulfur, nitrogen, or in this case, all of the above. You'll always have oxides as exhaust, and most of those are harmful to the environment. The exception here is hydrogen gas which forms water (steam) when burned. Unfortunately hydrogen gas has to be man-made, which requires energy. That energy usually means exhaust gases of some sort.

You should also consider the fact that fuel oil is around 80% carbon and around 2% sulfur. That means you're emitting 40 times more carbon dioxide than sulfur oxides. With cars, you're emitting 84000 times more CO2 than SOx.

Another fun fact is that the reason "car fuel" (gasoline and diesel oil) have so little sulfur in them is that all the sulfur in crude oil is left in there while valuable "clean" oils are extracted, and what's left is the fuel they use on ships. So basically, ships are burning the sulfur that would otherwise be burned in cars.

Comment Re:Could be a problem (Score 1) 595

It does, but the added cost is insignificant. Say a 300,000t ship uses 300t fuel per day, and carries enough fuel for a month. That's 9000t, or 3% of the entire mass of the ship (numbers roughly based on the Emma Maersk). Fuel consumption increases slower than total displacement (weight), so you'll use at most 3% more fuel.

So all you need to make it worthwhile is a price difference of 3%. I recently saw a price difference in fuel oil of around 80$/t between Saint Petersburg (Russia) and Antwerp (Belgium), on a price of around 500$/t. That's a 16% difference, and that's by no means extraordinary.

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