nickjarboe

Galileo and helicopters? I think you mean Leonardo da Vinci.

The Earth part was just shorthand for the fact that the atmosphere and gravity of Earth add about 1.3–1.8 km/s of delta v to achieving the pure kinetic delta v of 7.8 km/s needed to achieve LEO [1]. The first stage adds almost all of this "extra" delta v.

I was mostly just correcting your "one-sixteenth of the energy required for orbit" statement. I agree that reentering at 7.8 km/s is much more difficult than 2.0 km/s, but the second stage is smaller and more spherical than the first stage. That might make reentering it a bit easier than if it had the shape of the first stage.

[1] https://en.wikipedia.org/wiki/Low_Earth_orbit

Nit: The energy of an object going 2,000 m/s is 1/16th of that going 8,000 m/s, but since this is a rocket launching from Earth the energy for the rocket to get to 2,000 m/s is much greater than the energy to go from 2,000 m/s to 8,000 m/s [1].

Just look at how much larger the first stage (mass almost all propellant) is compared to the second stage (large fraction of the mass is the payload).

[1] https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation

If the world decides to leave fiat currencies and return to gold, the value of gold will be much (10x?, 100x?) higher.

I would suggest getting a "Benchmak Maps" atlas of the state you are traveling in. About $25 each. The whole state at 1:300,000 with comprehensive coverage of many features. You will find all the dirt roads and many trails. Good for driving into and around the back country. For hiking, especially off trail, I prefer good old 1:24,000 USGS maps.

The records before comprehensive satellite measurements are not very useful to determine a baseline.

When a city in America is destroyed by a nuclear explosion, Americans will re-learn why suburbia was so popular. Hopefully this won't happen for a long time and we will have a good stretch of city living. I love cities, but having millions of people concentrated enough to be killed by a single device; this is very different world than the one humans evolved in.

Google bought WAZE in 2013. I wonder why Google Maps would be so much better than WAZE four years later.

Not yet.

The journal article in Nature can be found here[1]. The abstract is publicly accessible with the article behind a paywall. I'm not familiar enough with the dating method to comment on the possible problems of the age determination, but it was calculated by the complicated method of "230Th/U radiometric analysis of multiple bone specimens using diffusion–adsorption–decay dating models indicating a burial date of 130.7 ± 9.4 thousand years ago."

[1]https://www.nature.com/nature/journal/v544/n7651/full/nature...

Running a rail line point to point is cheap? More like impossible.

As per the article, Vanguard's biggest fund is the Vanguard Total Stock Market Index which tries to track the CRSP U.S. Total Market Index. That index is "Nearly 4,000 constituents across mega, large, small and micro capitalizations, representing nearly 100% of the U.S. investable equity market." I don't think you have to worry much about a bifurcation between large and small companies. My worry would be that the "investable equity market" is shrinking and that most the growth in the future will come from companies pre-IPO where non-accredited investors cannot invest.

I think the idea behind farm to table is not that the owners of the restaurant supply everything they serve themselves but know their suppliers personally, maybe have been to the suppliers farm, and can answer detailed questions about their restaurants supply chain.

Individuals buying smaller amounts of stocks may not be exercising their votes or have a board member in their back pocket, but they can in the aggregate greatly influence one thing upper management does care about: the stock's price. Unfortunately, if you think management is too focused on the short term, if everybody investing with long horizons buys mutual funds and day traders focus on individual stocks, management is likely to be even more short term focused.

Farm to table restaurants are very trendy at the moment.

It seems to me that if a country has nuclear weapons and they are used in an attack, then one should desire them to be delivered by ICBM. Then there is no doubt where it came from and who attacked who. Living on the US Pacific coast, I sure do not like the idea of a North Korea with long range missiles, but they do have many submarines and a few nuclear weapons stealthily delivered by a few of those would have much worse long term consequences for civilization. The re-abandonment of American cities could happen just as they are starting to bloom once again after a long hiatus.

When the Whole Foods opened near me, for the first year, about half the time that I would shop there I had an item where the price they charged at the checkout was higher than the price on the shelf. No "free item if overcharged" deal like you see at many shops either. It was a bit of a pain to have to watch out for over charging, but it the problem went away eventually.

Still over 10,000 nuclear weapons [1]. Wish it was more like a hundred.

[1]https://ourworldindata.org/nuclear-weapons/

Nixon created the EPA. I don't think he was generally for hippie bullshit. If one is to believe John Ehrlichman[1], Nixon put marijuana on Schedule I to try and destroy the hippies.

[1]http://www.cnn.com/2016/03/23/politics/john-ehrlichman-richa...

The DOE is the department that designs, builds, and maintains the United States' nuclear weapons. I hope there is some science going on.

Fuel cells are expensive due mostly to the cost of platinum.

Some think that money in the form of shells existed back to at least 75,000 B.P.[1]. Language and controlled fire arose around the same time. Money (easily transferable anonymous debt) may have been used by (proto?)humans before the notion of words. Money may have been one of the few keys to the rise of human dominance.

[1]http://nakamotoinstitute.org/shelling-out/

Elon Musk believes this as well. In a 2012 interview by Chris Anderson published in Wired[1] on why SpaceX does not patent anything:

Anderson: So what have all your creative people come up with, then? What’s different in your basic technology versus 50 years ago?

Musk: I can’t tell you much. We have essentially no patents in SpaceX. Our primary long-term competition is in China—if we published patents, it would be farcical, because the Chinese would just use them as a recipe book.

[1] https://www.wired.com/2012/10/ff-elon-musk-qa/all/

Sort of like how sometimes when government tries to solve a problem with a certain program and, if the problem gets worse, the solution suggested (and often tried) is to give even more resources to the program instead of trying a different program with different people.

I agree independent space stations make more sense than anywhere but maybe Mars. Using small, near-Earth asteroids for bulk resources at first seems likely. But for political autonomy, near Earth is unlikely. Earth's political systems will have a high incentive to have some control over massive objects moving very fast near the planet.

World annual traffic deaths in 2010 were estimated by the WHO to be 1.25 million. If Elon Musk has the guts to let people voluntarily test out a system that ends up killing 100 people (and this estimate seems very high. The system could save more than it kills during development) but develops a system that reduces traffic deaths by just 50% one year earlier, that would be saving 625,000 lives. From a practical human suffering perspective, I am glad he is pushing hard to develop automatic cars a soon as possible.

Also: reusable rockets.

Political freedom has often been the primary motivation for groups of people to emigrate. Hypothetical sea-steading aside, moving somewhere with no existing political system in place is not possible on Earth. Wealthy patrons might sponsor the pioneers. This was how much of early New England was settled by Europeans.

Of course people play that way. It's the rules. :)

In recent geologic time CO2 levels seem to mostly be influenced by temperature instead of increasing CO2 levels causing temperature rise like today (there does not seem to be animals in past all of a sudden excavating and burning gigatons of carbon annually). Over million year timescales the biggest cause in the change in Earth's temperature is Milankovitch cycles[1] which is short hand for changes in the shape Earth's orbit and changes in the position of the Earth's spin axis. These changes interact to produce various climate conditions. The biggest factor is that sometimes these cycles cause the northern hemisphere to have very cold winters and other times mild winters. When the winters are very cold, continental glaciers can form on North America and Eurasia. They reflect more sunlight than land and the Earth gets colder. This is an ice age. Eventually the orbital and spin axis parameters change (over tens of thousands of years) and, with warmer winters in the northern hemisphere, the ice sheets begin to melt. With this positive feedback loop, the ice age ends quickly, the Earth gets warmer, and the Earth enters what is called an inter-glacial (we are in one now).

This is, of course, a very simplified explanation. As one goes back hundreds of millions to billions of years, other large scale changes like plate tectonics, atmospheric composition/mass, sun brightness, continental weathering, etc. will cause the average surface temperature to vary considerably.

[1]https://en.wikipedia.org/wiki/Milankovitch_cycles

Not sure if I'm missing a sarcasm tag in your comment but most places in the US restrict the number of places selling hard alcohol by having a restricted number of liquor licenses that trade on the open market like taxi medallions. In San Francisco for a restaurant this will set you back a cool 1/4 million[1] and the type 48 license you need to open a bar seem be sold so rarely in San Francisco I can't find any price reference online.

[1]http://www.mercerrestaurantgroup.com/how-to-open-a-restauran...