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Japanese Startup Wants To Rain Down Man-Made Meteor For Tokyo Olympics (sciencealert.com)
A startup called Star-ALE wants to create a man-made meteor shower over the city of Tokyo for the 2020 Olympics opening ceremonies. The pyrotechnics show, Star-ALE says, will be visible from an area 200km across Japan, and the pyrotechnics will actually shower from space. Starting next year, Star-ALE will begin sending a fleet of microsatellites carrying 500 to 1000 specially-developed pellets that ignite and intensely glow as they re-enter the earth's atmosphere. ScienceAlert reports: But wonderment comes at a cost, and in this case, that cost isn't cheap. Each combustible pellet comes in at about $8,100 to produce, and that's not including the costs involved in actually launching the Sky Canvas satellite. The company has tested its source particles in the lab, using a vacuum chamber and hot gases to simulate the conditions the pellets would encounter upon re-entering Earth's atmosphere. In its testing, the particles burn with an apparent magnitude of -1, which should ensure they're clearly visible in the night sky, even in the polluted skyline of a metropolis like Tokyo.
I really enjoy the sports at the Olympics, but I don't care for the excess. A big part of Greece's financial issues go back to the tremendous amount of public debt from hosting the Olympics in 2004. Priority should be given to cities that already have much of the required infrastructure instead of building it. There also needs to be a plan for how any new venues will be used in the future. In addition to being more financially responsible, it would be more environmentally friendly and produce less waste.
Greece would be in a better position to handle the influx of refugees if they weren't in a ridiculous amount of debt. Life in Greece would be much better off in general without the debt. A lot of that debt came from hosting the 2004 Olympics. In this case, Greece funded the Olympics with money they didn't have and might well not have otherwise been spent.
One thing that bugs me about this summary:
At orbital velocity (LEO) an object has a potential energy of around 30MJ per kilogram, an energy density higher than ethanol. Black powder, by contrast (common in fireworks) has 1/10th that energy density. The various colours, with the exception of white, are generally from rather weakly combusting compounds. There's a lot more energy to be had for producing "glow" from the orbital energy rather than whatever they want to burn to produce a coloured glow. And the colour of the thermal radiation from reentry will depend on the surface temperature, and that's customizeable for red, orange, yellow, and white (no green, blue or purple, though) just through simple blackbody emission, customizeable if specific ions are being ablated that tend to radiate in certain bands. The blackbody colour can be varied over the course of reentry by changing the drag coefficient as the surface ablates.
Perhaps "combustion" is the wrong term, perhaps they're just talking about ablation?
Honestly, you don't need special pellets to make a neat fireworks display, rockets can do that themselves ;) In fact... hmm... now that I think about it, the most cost-efficient way to get strange atmospheric effects might be barium clouds. They only require sounding rockets, the glow comes from the below-horizon sun itself, they show effects of the solar wind on the atmosphere (sort of like artificial auroras), and are often mistaken for UFOs and can look like slow fireworks when they expand.
Friends! Help! A guinea pig tricked me!
You can't just throw "money" at drugs, poverty, disease, hunger, and despair, and expect them to go away. In most cases, the money you're throwing goes directly into the hands of people who do the most harm with the most money.
Strangely enough, you can just throw money directly into the hands of the people who suffer poverty and hunger (rather than the middle-men) and it does actually seem to work. Here's an example from The Economist:
http://www.economist.com/news/...
"Now enough of these programmes are up and running to make a first assessment. Early results are encouraging: giving money away pulls people out of poverty, with or without conditions. Recipients of unconditional cash do not blow it on booze and brothels, as some feared. Households can absorb a surprising amount of cash and put it to good use. But conditional cash transfers still seem to work better when the poor face an array of problems beyond just a shortage of capital."
(I remember another funny quote from someone but can't find it just now, along the lines "The common characteristic of the poor is they don't have money, and it turns out that by giving them money we can change that.")