While fast radio bursts last just a few thousandths of a second and have rarely been detected, the new result confirms previous estimates that these strange cosmic bursts occur roughly 10,000 times a day over the whole sky.
That's a lot of aliens.
Well, since there are 100 to 200 billion galaxies in the observable universe, not so many. One burst per galaxy every 50,000 years or so.
Or maybe we are inside of a slow thinking alien's head.
It's worth pointing out that a good way to send a signal would be to have a bright but transient beacon, which doesn't itself transmit information (other than "here I am"), but serves to tell others where to point their high-gain radiotelescopes.
This could be what such a beacon would look like.
Not to mention the power output it would need to send a detectible signal from another galaxy.
From the summary: "bright flashes of radio waves that last only a few thousandths of a second.
A high power for a few milliseconds may not take an enormous amount of energy.
Without dimmers, I've been hard pressed to see the difference between brands.
The differences are not easily visible from the outside. Some brands have gone through some pretty rigorous lifetime testing-- humidity, voltage variation, temperature-- while others are just "as long as it works long enough for the consumer to throw away the receipt" made, but you can't really tell by just looking at them.
Also, Lumens per watt can vary quite significantly from one to another.
Interesting data point.
Only one of my fixtures has a dimmer, the light over the dining room table. For reference, the fixture has five Philips bulbs in it, and they dim fine, no noticible flicker.
Obviously, results vary.
Want dimmable ones so they'll be pricy initially.
Dimmable LED bulbs used to be more expensive. These days pretty much all the LED bulbs you see around are dimmable, even the low cost ones.
I started converting my bulbs to LEDs back in 2008, so my oldest bulbs are six years old, and still running.
However, the question was about my most RECENT bulbs. I got two last month. Neither one has failed in the three weeks I've had them, so I have to vote "Never had one fail."
at 400 C, radiant energy starts doing a fair amount of the heat transfer. At 800 C, radiation overwhelms convection.
800 degrees C??? That's 1470 degrees F! Who has an oven that goes that high? That will turn just about anything into charcoal in under a minute.
Even 400 C-- 750 degrees F-- is quite a bit hotter than most ovens.
Agreed, I worded it badly. How about: ''How long had the last energy saving bulb that you replaced been working ?''
About six days, since you ask. Is that useful information?
But it is not intended to be a scientific survey.
Well, as the disclaimer says, Slashdot surveys aren't.
Following on from the current poll: How long did your last energy saving bulb last ? 0-1 months; 2-4; 5-8; 9-14; 15-23; 2 years; 2-3 years; 4+ years
If "last" means "most recently purchased", how do you answer for a bulb purchased two years ago that's still working? Or, for that matter, a bulb purchased last month?
My answer to this question is rather variable-- I've been changing out pretty much all of my bulbs for LED lamps. And I don't necessarily buy the cheapest ones. However, as it turns out, the ones I bought most recently were a couple of candelabra LED bulbs for the front entry chandelier, and they were pretty cheap. I was, however, also looking at LED strips to replace 4-foot fluorescent tubes-- if that had been my purchase, it would definitely have hit the "over twenty dollar" mark. (EarthLED has these. Some of these require rewiring to remove the ballast, although the Philips ones apparently are drop-in replacements)
I replaced the kitchen lights with LEDs. About $22 a pop. These are the larger lights, not the incandescent sized bulbs.
Excellent application for LEDs-- omni bulbs are far less efficient in that application than LED spots. (Any place where the required light is not omnidirectional is a good application for LEDs.)
...over many decades. Cars are driven on billions of trips-- trillions of miles-- per year. Really, truly, there are differences of many orders of magnitude here.
There aren't thousands of rocket launches.
It's not, and it also annoys me when people say that.
No single hurricane, heat wave, tornado, flood, wildfires due to drought, storm surge, hot summer, rainy winter is due to global warming, just as no single cold snap, hurricane free season, unseasonably cool spring, early winter storm is evidence that global warming isn't real.
Those are all weather. Climate is long term.
Trivially, no single car trip has an effect on global carbon dioxide. It's a collective effect. Being a collective effect does not make it nonexistent, but it does make it a problem hard to solve, since the problem is distributed.
So, here's an interesting question-- and I'm not being sarcastic here, I'm being real. Given that no one car trip has an effect on global carbon dioxide, but a hundred billion car trips do have an effect, what would be an appropriate approach to addressing this impact?
Wait, doesn't your rebuttal show that the earth's temperature will not spiral out of control leading to the death and destruction predicted?
I don't recall ever making such a prediction.
To be honest you make great points for the view that we are really in a geologic cold period and global warming is just returning us to average temperatures for geologic time frames.
Yep, that's pretty much correct. The Earth is, on the average, quite a bit cooler than it has been in the geological past. It does not always have ice caps.
It happens that this is the climate that we humans are used to, and we've rather built our habitats and our agriculture around. But, on a geological scale, a few degrees of warming, and melting the polar ice caps. is no big deal. It's not the end of the world.
--unfortunately, when we return the planet to the climate conditions of the Jurassic, we probably don't get the dinosaurs back. But then, if biological research keeps on track, we'll just make new ones.
Love may laugh at locksmiths, but he has a profound respect for money bags. -- Sidney Paternoster, "The Folly of the Wise"
