Beta

×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

Comments

top

NASA Tests Microwave Space Drive

gewalker Re:KSP (157 comments)

You have to be more even more patient than they are for a probe. To accelerate from low earth orbit to escape velocity the 1e-7 m/s^2 will take 1080 years. Enough for orbit maintenance, probably. Enough for probes, no not really -- No one plans for missions spanning thousands of years.

yesterday
top

NASA Tests Microwave Space Drive

gewalker Re:KSP (157 comments)

Oops, off by a factor of 10. 1 year give 3.15 m/sec 7.05 m[h

yesterday
top

NASA Tests Microwave Space Drive

gewalker Re:KSP (157 comments)

No, the question is how fast can it accelerate the average potato. NASA reported 30-50 mN of thrust., call it 40. The average potato is about 375 grams, call is 400 even so math is real east. F=m*a or a = F / M or 1e-7 m/sec^2. So, accelerate for 1 year and you reach the break-neck speed of 31.5 meters per second or 70.5 mph

It is going to take a long time to get that potato to Alpha Centauri. Especially considering that you have to also accelerate the mass of the Q-drive unit itself and the energy source to supply the Q-drive.

Now if the effect is real and the efficiency and can be improved you still have something potentially useful in-deed for satellites. You could even maneuver asteroids if you had lots of patience.

yesterday
top

Chinese Government Probes Microsoft For Breaches of Monopoly Law

gewalker Re:I'm sorry to be the grammar Nazi... (107 comments)

I must be one of those grammar Nazi's too, because I laughed at this joke.

2 days ago
top

Greenpeace: Amazon Fire Burns More Coal and Gas Than It Should

gewalker Re:Time to start building more nuke plants as long (288 comments)

TMI safety both failed and succeeded depending upon how you look at things.

It failed to prevent a partial meltdown of the reactor core.

It failed to prevent a significant release of radiation to the general environment as 15 curies (560 GBq) of iodine-131 (the most concering portion due to biological uptake to the thyroid)

It succeeded in terms of avoiding the wide-scale problems of Fukushima or Chernobyl

It failed in terms of public opinion of nuclear power being a reasonably source of energy production. Nuclear plant construction in US was virtually shut down after this, no new licenses till 2012.

 

about a week ago
top

Earth In the Midst of Sixth Mass Extinction: the 'Anthropocene Defaunation'

gewalker Re:To this day, 95% of our earth’s oceans re (338 comments)

Let's see, Pacific, Indian, Atlantic, Arctic. You mean there are 76 more oceans out there. And if you count the southern there is another 95 of those suckers.

Holy cow, wait till Exxon finds out!

about a week ago
top

Earth In the Midst of Sixth Mass Extinction: the 'Anthropocene Defaunation'

gewalker Re:no problem (338 comments)

On the contrary, the mammoth was a work animal. Work animals and food animals are very well preserved in terms of extinction rates.All you have to do it visit the lot of Bedrock Mammoth and you would see the wide selection of available animals.

about a week ago
top

One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

gewalker Re:... and that's not much. (190 comments)

Cs-237 is pretty hot, half life of about 30 yrs. How about

Pu-239 .435 kg
U-235 12500 kg
U-238 80,400 kg.

I am sure these sound scary to most people, though Cs-237 is presumably a significant component of the nuclear release in question.

Of course they sound much worse because you can make nukes out of these and that increases the radiation release rate by many orders of magnitude and that mushroom cloud, etc.

To Americans it's Cesium not Caesium, then again most American don't really know what that it is. And most don't understand radiation either.

about a week ago
top

One Trillion Bq Released By Nuclear Debris Removal At Fukushima So Far

gewalker Re:I also measure distance (190 comments)

Conveniently, there is an even better comparison. You have to disperse all of the radioactive soil into the air to make a similar comparison. We don't actually pump soil into the air though. We do however burn coal.

Webpage According to the National Council on Radiation Protection and Measurements (NCRP), the average radioactivity per short ton of coal is 17,100 millicuries/4,000,000 tons, or 0.00427 millicuries/ton. This figure can be used to calculate the average expected radioactivity release from coal combustion.

Converting this to metric equates to about 0.174 MBq/ton (metric ton).

WebpageLargest coal plant in America burns 11 millions tons of coal per year.

Now 11,000,000 tons * 0.174 MBq / ton is 1.914e6 MBq -- a bit less than the twice the totally scary 1 trillion Bq

The average coal plant burns coal with around 0.5 trillion Bq / year

Now, not all of the radiation get released into the atmosphere, a lot of it ends up in the ash. But the ash is stored in ponds and left in piles on the ground, so its not a terrible improvement in terms of safe radioactive containment.

about a week ago
top

Lawrence Krauss: Congress Is Trying To Defund Scientists At Energy Department

gewalker Re:Good (309 comments)

I would settle for nice modular neighborhood-scale TFTR reactors for now. I don't expect to see Mr. Fusion in the years I have left. I don't expect Congress to contribute to either of these either. I might wish they get rid of some unneeded regulations, but I have little hope of this happening either.

about a week ago
top

Comcast Carrying 1Tbit/s of IPv6 Internet Traffic

gewalker Saying something good about ComCast hurts my brain (146 comments)

In actual fact, the ComCast internet service is not too bad. It is just their customer support, pricing, monopoly status and general arrogance that make them among the most hated company in existence.

The other interesting thing in the article was Google showing their IPv6 traffic was now around 4% up looked the perhaps the upward bend at the beginning of an s-Curve.

about a week ago
top

EPA Mulling Relaxed Radiation Protections For Nuclear Power

gewalker Re:headed in the wrong direction (230 comments)

According to scientist, the common view is that the linear no-threshold model is actually the flawed viewpoint. See this article for a pro-radiation view that is not commonly reported. Although most people will scoff, there is actual evidence that a little ionizing radiation is good for you.

Yes, I would participate in the study that installs a radioactive source in your house (at reasonably low levels) because I believe the data that I have been able to find in the past.

about two weeks ago
top

Comcast Customer Service Rep Just Won't Take No For an Answer

gewalker Re:Burn in Hell (401 comments)

Under the proposed terms of the merger, the combined Comcast / Time Warner will divest themselves of some of their users due to anti trust concerns. I am in that group to be divested.

about two weeks ago
top

Comcast Customer Service Rep Just Won't Take No For an Answer

gewalker Re:Burn in Hell (401 comments)

But if the merger goes through, I get divested out of ComCast.

On the one hand, expletive of choice Comcast

On the other hand, expletive of choice, no more Comcast, woot!

Clearly my loyalties are divided on this issue.

about two weeks ago
top

Asteroid Mining Bill Introduced In Congress To Protect Private Property Rights

gewalker Re:Sure there is (181 comments)

Go ahead a look up what kind of telescope you need for this, your choice for wavelength. Poster was saying, mass drivers were useless in space war because you could dodge. Painting it black was a joke because it does not matter at all.

A 10 kg sphere of DU is conveniently almost exactly 5 cm in diameter. Let me save you some trouble, the Hubble has a resolution of about 0.1 arcseconds, which means a football stadium on the moon (about 384,000 km) is needed to resolve as a single pixel on the Hubble CCD's (radar has worse resolution, higher frequency gives better resolution). So for convenience, lets assume our slug is exactly 20000 times smaller in diameter, which means it would have to be 20000 times closer (19.2 km) to be imaged by the Hubble -- giving you a grand total of 0.001 seconds to dodge the incoming round. A additional problem, you have to be pointing your telescope directly at the slug in order to see it. High mag. scopes have a limited field of field. Also, due to orbital mechanics and a long time of flight you could easily lob thousands of slugs on different trajectories all designed to arrive at the time time.

K/E weapons are truly difficult to defend against. Now, a 10 kg slug at 20 kps exceeds the capabilities for any existing railgun I know of, it won't for long though, maybe a few decades. It will still be a heavy piece of equipment for some time to come. But given sufficient motivation they will eventually end up is space unless we find something better first.

about three weeks ago
top

Arecibo Radio Telescope Confirms Extra-galactic Fast Radio Pulses

gewalker Re:First contact? (95 comments)

It is a very narrow beam, but they don't point it in our direction. Imagine a then wedge of laser/maser, etc. light being broadcast outward radially on a continuous basis. As the planet rotates, the wedge sweeps pretty much every angle. As you see the wedge only when it points directly at you, it appears to blink very rapidly

about three weeks ago
top

Asteroid Mining Bill Introduced In Congress To Protect Private Property Rights

gewalker Re:Sure there is (181 comments)

Not if you paint it black. Forget that, what kind of magic telescope do you have to see a 10 kilo slug of depleted uranium fired at 20 kps to give you any chance to see it it time?

about three weeks ago
top

William Binney: NSA Records and Stores 80% of All US Audio Calls

gewalker Re:No one cares, so why does it matter? (278 comments)

Your point is well taken. Here is one suggested action. Try to wake up the sheep, enough to actually make a difference. Post the article to facebook. Here is how I posted it to my account.

I'm not much of a conspiracy guy, but our gov. is getting really out of control and scary. This is in my mind a pretty credible source. http://www.theguardian.com/com... -- that does not guarantee that is in fact true, but I believe that it is.

Clearly there are other ways. Write / call the appropriate politicians, etc. You know more possibilities, no need for me to rant here.

about three weeks ago
top

William Binney: NSA Records and Stores 80% of All US Audio Calls

gewalker Re:Speech to Text (278 comments)

What makes you think they don't monetize this already. How else do you get funds needs for black projects.

about three weeks ago

Submissions

top

Major Data Brokers hacked by ID Theft Service

gewalker gewalker writes  |  about 10 months ago

gewalker (57809) writes "Have we reached the point where it is time to admit that the ID thieves are winning and will continue to win as long as their incentives are sufficient to make it lucrative for them? According to Krebs On Security a breach in 25 data brokers has been identified including the heavyweights Dun and Bradstreet and LexusNexus. The truly telling quote is

“We could well be witnessing the death of knowledge-based authentication, and it’s as it should be,” Litan said. “The problem is that right now there are no good alternatives that are as easy to implement. There isn’t a good software-based alternative. Everybody in the industry knows that KBA is nearing its end of usefulness, but it’s not like you can instantly roll out biometric identifiers to the entire US population. We’re just not there yet. It’s years away. If ever.”

"
top

Microsoft restores transfer rights to Office 2013

gewalker gewalker writes  |  about a year ago

gewalker writes "Bowing to significant unfriendly customer feedback regarding its new "no transfer" license for Office 2013, Microsoft recants and allows Office 2013 licenses to be transferred between computers. Actual license language will not be reflected for a few months for shipped products, but Microsoft will allow transfer of license effective immediately. Calls to customer support will be necessary as the activation servers won't be updated for a few months."
Link to Original Source
top

First evidence of gravity waves

gewalker gewalker writes  |  about 2 years ago

gewalker writes "This is supposed to be published soon in "The Astrophysical Journal Letters", but in short researchers claim they have detected gravity waves from the husks of 2 stars 3000 light years away. They are losing energy and circling each other faster over time as the gravity waves remove energy from the orbits of the pair. This energy loss agrees with the prediction of general relativity — not a direct observation of gravity waves."
Link to Original Source

Journals

gewalker has no journal entries.

Slashdot Login

Need an Account?

Forgot your password?
or Connect with...

Don't worry, we never post anything without your permission.

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>