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Comment Re:Travelling at 20% of the speed of light (Score 3, Informative) 218

I love the whole "it's only 20 years if you travel at 20% of the speed of light!" part. It makes it sound so close. But you're not going to snap your fingers and jump right to 20% of the speed of light from one second to the next. That's 6,114,064.6 standard Earth g-forces! You'd be much better off having a slow, steady acceleration all the way there and a slow, steady acceleration all the way back. Unless I did the math wrong, you'd need to maintain about 0.38 m/s^2 (yeah, I rounded - I'm not the one sending the craft) the entire trip. ...

The interstellar space probe concept mission they are referencing is this one by Philip Lubin. The scheme has the 70 gigawatt launching lasers accelerating a tiny wafer thin probe to 20% c in 10 minutes, which is about 10,000 gees. A tiny wafer thin structure can handle that. And no, there is no slowing down. These things fly through the target system at 0.20 c, and keep on going.

Comment Perhaps This Will Get Habex Funded (Score 5, Informative) 218

Those relativistic postage stamp sized probes are a dream at present. Long before we could develop the technology for this, or get funding, we will study this planet with the advanced space-based instruments with capabilities far beyond anything now existing. No probe will be sent until we reach the limit of what we can do within our own solar system - nothing is faster than analyzing the light that already gets here, and even the most extravagant telescopic system will be cheaper than the probe project and all its supporting infrastructure.

That leads us to consider the HABEX Mission a pretty cool project under development using the huge and really cool looking Starshade vehicle to provide a coronagraph for a telescope in a separate vehicle thousands of kilometers away. Having a nearby target like this gives leverage with Congress to appropriate the funds.

Comment Re:i'd like a water proof phone (Score 2) 385

I for one would like an iPhone that's totally wa ter proof headphone jack: bluetooth lightning port : inductive charging

would be completely water proof with no external buttons -- how is that a bad thing exactly?

Because a lot of people dont want to keep getting adapters to make things work. Personally I prefer having the option to use BT or wired headphones. Yes, keeping it waterproof would be nice. But I would prefer to have the 3.5 headphone jack.

Quite so. I have yet to drop any cell phone in the water, or to want to make a phone call while swimming. But I use the 3.5 mm constantly, every day.

Nobody is demanding Apple drop the headphone jack, and almost nobody is demanding a thinner phone (look at the cases people use that make it fatter).

I predict that with iPhone sales down, this will NOT goose a new surge in buying, and that the jack will back e'er long.

Comment Re:This list sucks ass (Score 1) 282

Quoting IEA EEMR 2014 "In 2011, energy savings from continued improvement in the energy efficiency of 11 IEA member countries equalled 1 337 million tonnes of oil-equivalent (Mtoe). This level exceeded the total final consumption (TFC) from any single fuel source in these countries, and was larger than the total 2011 TFC for the European Union from all energy sources combined. Energy efficiency savings in 11 IEA member countries were effectively displacing a continentâ(TM)s energy demand"

On clean energy it isn't production stupid it is storage an issue completely ignored by the author.

Regarding energy efficiency, you are +5 here. This is absolutely bang-on.

But you are off-base about storage. Storage has a role, but it is a minor one. The major solution for managing clean energy production is transport. On a continent-wide scale problems with regional variation largely disappear. Using a proven technology that has been in use for more than 80 years - high voltage DC transmission lines - electricity can be shipped from San Diego to Portland, Maine with only an 8% loss (800 KV line).

Comment Energy Demand is Dropping (Score 2) 282

2. Clean Energy: Attempts to fight climate change by reducing the demand for energy haven't worked. Fortunately, scientists, engineers, and entrepreneurs have been working hard on the supply side to make clean energy convenient and cost-effective.

The haven't worked enough perhaps, but they have absolutely been working. Energy intensity, the amount of energy required to produce a unit of GDP has been falling everywhere, and the best economies far out perform the lagging ones (like the United States) so even just implementing proven existing techniques would have great impact. And energy efficiency technologies are making rapid progress - automated control, LEDs, etc. The bang-for-the-buck in energy efficiency is almost always larger than in energy production (i.e. the cheapest energy is the energy that you didn't use). Going forward, emphasis on energy efficiency will be fully as important as changing modes of energy production.

Comment Re:Please explain (Score 5, Interesting) 271

Please explain the following:

1.) When the weather is hotter than normal, it's evidence of Global Warming (or climate change), but... 2.) When the weather is colder than normal, the AGW apologists immediately remind us that Weather is not Climate.

If indeed the Earth is getting warmer, the press sure aren't doing the AGW advocates any favors with stories like the above.

These stories about extreme weather events only reinforce the perception that it's all a scam for political control. It's not helping.

I'll explain under the assumption that this is an honest request for elucidation (but that this is an AC post is not promising).

The article is not stating that it is "hotter than normal". It is stating that is hotter than ever recorded, indeed hotter than any time in the last 100,000 years. July is typically the hottest month so one expect historic records to be broken in July, and the last time the record was broken was - last July. If we go by seasonal records (hottest January, hottest February, hottest March, etc.) the last time was such a record was broken was - last month. And the last time before that was - the month before, and so on and so on.

When was the last time that it was colder globally than ever before recorded? Based on a relatively recent 1961-1990 average the last time we had a cooler than average month was 31 years ago.

Comment Re:We all need to be nervous. (Score 1) 271

It's simply shifted the trend upwards.

Well at least you aren't denying the steady trend of global temperatures marching higher and higher, year after year. Remember this is the warmest month ever recorded, which makes it the warmest month since the last Ice Age (we passed the historic peak since the last Ice Age a decade or more ago). And that makes it the warmest month in the last 100,000 years.

A bit like saying that a steadily sinking boat, as it bobs up and down, will be higher and lower, since natural wave variation has not stopped, it is simply shifting the trend downwards. You reach a point where the stop being complacent because you drown.

Comment Re:Glass blowed 0g habitats (Score 1) 88

Use big mirrors

Only in science fiction would "giant mirrors" be available for a purpose like this, but not a ready built habitat.

Bingo! Give the (anonymous) man a cigar.

Much of what gets posted here when it comes to space exploration are just science fiction plot gimmicks having little bearing on reality.

Comment Re:There's a reason for that. He's the only racist (Score 1) 531

who could be elected president. His fan base are white racists - they have no other options.

It's clear there is a section of his support base for whom this is true, but if that were all he had, or even most of what he had, he'd have no chance. No, much more of his support comes from people who deeply oppose globalization and people who are just mad at the establishment and want anything else.

I have to admit that the clearly racist part of his base is, sadly, much larger than I thought it could be.

A simpler theory is simply that "leaned Republicans" (in Pew Polling terminology, self identifying Republicans plus Republican leaning "independents") will vote as they always have, pulling the lever for the "R" regardless of how qualified or unqualified that person might be. 85% of all "leaned Republicans" plan on voting for Trump. Evangelical Republicans support Trump at a rate of 94%, they constituted nearly half of all the votes Romney got.

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