Years ago, there was one popular handheld GPS receiver which was deliberately crippled to crap out above 99 knots. This so that anyone wanting to use one on a plane, as opposed to a boat or hiking or whatever, would be compelled to buy their vastly more expensive aviation receiver.
My Garmin 12XL works fine on planes. I haven't used it on airline flights much, but the few times I have, it was run to see the "velocity" reading showing 450 knots.
As for maximum speed, I used to work at a place which made advanced receivers for the military. We had a test scenario we'd put the receivers through which had it "flying" at 1000 meters per second. Maybe an SR-71 could do that. I bet it wouldn't do the 10 G turns that
were also in that test scenario, though.:-)
And there have been GPS receivers made which will work on spacecraft in orbit. Nearly
8000 meters per second.
IIRC one of the crewmen mentioned "30 million kilometers per second".
That's 100 times the speed of light. As someone pointed out, at 4 days travel time, that puts Kronos 1.1 light years away. Impossible.
In Voyager they seemed to be approximately 1000 times the speed of light. They estimated 70 years to cross the galaxy -- approximately 70000 light years.
IIRC in the episode where they found Emelia Earhart, she asked how fast their ship went, and IIRC Perris told her a number. Anyone remember what it was?
GPS doesn't work at supersonic speeds anyway so there wouldn't be much point in having it.
Some GPS receivers won't. They most certainly can work supersonic. Some spacecraft use them, and that's mach 25.
I remember running GPS receivers on a test setup which simulated the signals transmitted by satellites. One scenario we used had the GPS receiver "flying" at 1000 meters / second
.
Given that speed, I guess that would be a SR-71. Except for the part about it doing 10 G
accelleration turns every minute.
This of course wasn't a $200 consumer handheld GPS receiver.
Shortly after
Mars Climate Observer disappeared, we had a good presentation at Orange County Astronomers from someone from JPL. He talked some about what they believed went wrong, and more in general about the reliability - cost tradeoffs.
The premise is that on one had they can build spacecraft cheap (relatively), and have much or most of them not work. Or spend vast amounts of money checking and rechecking everything, and desining in tons of reliability, then they'd still only reach the
reliability of the launch vehicle itself, so they'd still lose 1 in 20 or so.
Their studies had concluded that to get the most amount of science done for a given amount of money spent, they should expect to lose about 1 in 5 spacecraft. Pretty close to what has actually happened.
A long time ago, in a galaxy far far away
(to coin a phrase), I read that the death star
battle scene, specifically the "flying down a trench
to hit a target" part, was inspired by an old
war movie.
If you live in the Bay Area, a contemporary copy of the customs declaration (probably required in triplicate) can be seen on USS Hornet, the aircraft carrier (now a floating museum in Alameda) that hauled many of the Apollo capsules out of the Pacific and took them to Hawaii. It was clearly done as a tongue in cheek thing by US Customs, and possibly to cop a little reflected glamour from the moon shot.
Reminds me of something similar.
In the book Lost Moon, about the Apollo 13 mission, it says that the geeks at the contractor that built the lunar module sent the geeks at the contractor that built the (broken) command module an invoice, for towing charges, oxygen supplies, electrical power, etc.
What effect would a planned asteroid flyby have on the moon? The moon affects the world greatly. If it's orbit became closer, tides would increase. If we lost the moon, tides would all but disappear.
In addition, the moon stabilizes the earth's rotational axis. Without it, it's been simulated that the earth's axis would drift dramatically over the long term, having huge effects on climactic seasons.
That's just the most obvious effects. Any sudden change in the moon's orbit is bound to affect us.
I remember well when there was a real, unplanned blackout in San Francisco for about 6 hours. It happened back in 1998 - it was quite a surreal experience.
There was also the big one in summer 1997 (?). I remember that my fan slowed down drastically for about 15 seconds. My Linux box crashed of course, but my Mac and my Sparcstation didn't.
I tried calling SCE but got a fast busy signal, so I gave up. Then about 20 minutes later, power blew out completely,
Once I thought to turn on my radio, I heard word that power was out all over the west coast.
My understanding is that a major power line coming from Washington got damaged. Because we in California don't have nearly enough local power capacity, scattered areas all over CA were blacked out to not overload what we do have.
Power was out about 2 hours for us in Orange. It was back before night, so I didn't even get to do any good astronomy. I heard power was out well into night elsewhere.
Personally I find it bewildering that the US is unable to produce enough power to keep going. Even though the UK is not always able to meet peak demands, when we do have a shortfall we can cover the extra by using spare capacity from France. Who in turn can call on half of Europe.
Do note that a large fraction of France's electrical power generation is from nuclear reactors.
The symbol of the real problem IMO is that, despite no new power plants being built in ages (20 years in Los Angeles county), new houses are going up constantly. (At $400k a pop.) Just wait until they all fire up their air conditioners.
Never mind the energy and traffic issues with all the SUVs their owners will be driving.
How do you also nuke the ``Security'' widget from the toolbar? Since it does exactly the same thing as the padlock icon in the lower left corner, having it in the toolbar is a waste.
Also, the most crucial Netscape customisation,
Netscape*blinkingEnabled: false
hasn't worked since I switched from version 3.04. FWIW, I use the communicator-smotif-47 package in the Debian Linux distribution.
In Navigator you can stop animations once the page is loaded, using the ESC key.
Sometimes. Often I find that they start right back up again. If I was proficient with the junkbuster configuration files, I'd immediately add any animation that did that into my killfile.
BTW, the downloadable Macintosh version of QuickTime
also has the annoying register message. If you upgrade your Mac to System 9 you get a registered player.
I installed installed MacOS 9 (fresh format and reinstall) and the QT4 player is still nagware.
Not displaying animated gifs is a FEATURE, not a bug.
Yes! When Opera is finished, it at the very least should have an easily accessable control (not buried under 4 hierarchical menu levels) to disable animated.gifs.
I would like to have an option or something to stop the animation of banners, like the ESC key in netscape.
Definitely! I won't be using Mozilla much until I can either do that or disable image loading entirely. And no, I also haven't been able to get Mozilla (19991214.M12pre) to work with junkbuster, either.
Actually, I think on browsers there ought to be separate, one-click buttons, which will either disable animated.gifs, or disable image loading. I don't want to have to descend through 3 levels of hierarchical menus to change these settings.
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My Garmin 12XL works fine on planes. I haven't used it on airline flights much, but the few times I have, it was run to see the "velocity" reading showing 450 knots.
As for maximum speed, I used to work at a place which made advanced receivers for the military. We had a test scenario we'd put the receivers through which had it "flying" at 1000 meters per second. Maybe an SR-71 could do that. I bet it wouldn't do the 10 G turns that were also in that test scenario, though. :-)
And there have been GPS receivers made which will work on spacecraft in orbit. Nearly 8000 meters per second.
This is with Internet Exploder version 5 on the Mac.
That's 100 times the speed of light. As someone pointed out, at 4 days travel time, that puts Kronos 1.1 light years away. Impossible.
In Voyager they seemed to be approximately 1000 times the speed of light. They estimated 70 years to cross the galaxy -- approximately 70000 light years.
IIRC in the episode where they found Emelia Earhart, she asked how fast their ship went, and IIRC Perris told her a number. Anyone remember what it was?
"If we need to use the ejection seats, my signal will be the words, eject eject eject."
"If you do not eject at this point, you will be pilot in command of the aircraft for the rest of your life."
Some GPS receivers won't. They most certainly can work supersonic. Some spacecraft use them, and that's mach 25.
I remember running GPS receivers on a test setup which simulated the signals transmitted by satellites. One scenario we used had the GPS receiver "flying" at 1000 meters / second .
Given that speed, I guess that would be a SR-71. Except for the part about it doing 10 G
accelleration turns every minute.
This of course wasn't a $200 consumer handheld GPS receiver.
You can't rotate quickly or everyone will get motion sickness. Studies I've heard of indicate a rule of thumb is one revolution per minute maximum.
Do the math. To provide 1 G of rotational accelleration at 1 RPM , you have to have a radius of about 900 meters.
w = (1 / 60) * 2 * 3.1416 = 0.105 radians / second
a = w^2 * r
1 G = 9.8 meters / second^2
9.8 = 0.105^2 * r
r = 894 meters
The premise is that on one had they can build spacecraft cheap (relatively), and have much or most of them not work. Or spend vast amounts of money checking and rechecking everything, and desining in tons of reliability, then they'd still only reach the reliability of the launch vehicle itself, so they'd still lose 1 in 20 or so.
Their studies had concluded that to get the most amount of science done for a given amount of money spent, they should expect to lose about 1 in 5 spacecraft. Pretty close to what has actually happened.
Anyone know if this is true, and which movie?
Reminds me of something similar.
In the book Lost Moon, about the Apollo 13 mission, it says that the geeks at the contractor that built the lunar module sent the geeks at the contractor that built the (broken) command module an invoice, for towing charges, oxygen supplies, electrical power, etc.
Nice job!
In addition, the moon stabilizes the earth's rotational axis. Without it, it's been simulated that the earth's axis would drift dramatically over the long term, having huge effects on climactic seasons.
That's just the most obvious effects. Any sudden change in the moon's orbit is bound to affect us.
I tried calling SCE but got a fast busy signal, so I gave up. Then about 20 minutes later, power blew out completely,
Once I thought to turn on my radio, I heard word that power was out all over the west coast.
My understanding is that a major power line coming from Washington got damaged. Because we in California don't have nearly enough local power capacity, scattered areas all over CA were blacked out to not overload what we do have.
Power was out about 2 hours for us in Orange. It was back before night, so I didn't even get to do any good astronomy. I heard power was out well into night elsewhere.
By contrast there are only two nuclear power plants left in California., producing all of 14% of our power.
The symbol of the real problem IMO is that, despite no new power plants being built in ages (20 years in Los Angeles county), new houses are going up constantly. (At $400k a pop.) Just wait until they all fire up their air conditioners.
Never mind the energy and traffic issues with all the SUVs their owners will be driving.
But that and some pointers to the download site comes up fast, though.
Also, the most crucial Netscape customisation,
Netscape*blinkingEnabled: false
hasn't worked since I switched from version 3.04. FWIW, I use the communicator-smotif-47 package in the Debian Linux distribution.
Yes! When Opera is finished, it at the very least should have an easily accessable control (not buried under 4 hierarchical menu levels) to disable animated .gifs.
Mozilla needs this too.
% telnet www.w3history.org 80
Trying 151.196.211.136...
telnet: Unable to connect to remote host: Connection refused
OK, I'll post the URL for adzapper since I just looked it up.
http://www.halcyon.com/adamf/adzapper/
Definitely! I won't be using Mozilla much until I can either do that or disable image loading entirely. And no, I also haven't been able to get Mozilla (19991214.M12pre) to work with junkbuster, either.
Actually, I think on browsers there ought to be separate, one-click buttons, which will either disable animated .gifs, or disable image loading. I don't want to have to descend through 3 levels of hierarchical menus to change these settings.
Sorry, connection to host www.britannica.com on port 80 refused.
Survey says...
E = mgh
m = 1 kg
g = 9.8 m/s^2
h = 1 m
E = 9.8 joules
You forgot the accelleration of gravity.
Could someone post a direct URL to a text-only or ``printer friendly'' version of this article? It crashes my browser when I try to view it.