Even when I was growing up (in the 1950s) my first impressions of astronomy were formed by illustrations of the solar system--shown from a point of view outside the system, with the orbits displayed as brightly colored, ellipses...
Now that would be cool; standing at a point where the ecliptic plane is right overhead, and seeing a bright red ribbon erupting from the ground, extending straight up as far as the eye can see. The eruption point would move at 1600 km/h and the ribbon itself would move up at 29 km/s. I'm so disappointed this doesn't happen:-)
The numbers gathered by the Nazis in WW2 agree with the numbers gathered after the war by people unsympathetic to the Nazis. How much more confirmation do you need before you cross the line from sceptic to denialist?
At first glance, it would seem that a circular orbit can still lead to varying tidal forces. The only requirement is that the planet is not tidally locked to the moon (i.e. the planet's rotation is not in sync with the moon's orbit). Or am I overlooking something?
I'd be really "easy" to land if they had an RCS, just a couple seconds worth to cancel out any lateral movements and rotations
In its current configuration, the stage can't hover: on its lowest thrust setting, the engine still provides too much thrust. So they land using a "hoverslam" maneuver where they try to decelerate to a vertical speed of 0 just as the stage intersects the barge.
There is an RCS at the top of the stage to keep the stage upright, but any lateral thrust at the bottom has to be done by gimbaling the main engine. The gimbaling angle is limited so they may have run out of control authority on this landing.
The only thing you can remotely call a "day" on the ISS is about 90 minutes long.
The astronauts are on a 24-hour work/sleep cycle. It may not have anything to do with sunrises and sunsets anymore (1), but is there any reason other than extreme pedantism to not call that cycle a day?
1: other than the sunrises and sunsets over the control centers in Houston and Moscow.
An extended play tape cassette could store 3 hours of audio per side
I'm sorry, a what now?
The Compact Cassette standard had one tape speed (4.76 cm/s). Readily available cassettes came with 60-minute or 90-minute runtimes (total). You could get C-120 cassettes with 1 hour per side, but those used extra-thin tape that jammed easily. The longest tapes ever made were C-180, for 90 minutes per side, these used even thinner tape and so unreliable they never sold widely. I've never seen one, and I was a bit of an audiophile in those days. You'd have to combine a C-180 tape with a non-standard playing speed (used only in dication machines) to get 3 hours per side.
Excel (first introduced on the Mac in 1985) was a huge step forward from Lotus 1-2-3. Word (first graphical version also on the Mac in 1985) blew WordPerfect right out of the water. Developing these for the Mac gave Microsoft a taste of what a GUI could do, which was much more than Lotus and WordPerfect were doing with their crappy GUIs grafted onto CLI programs. Even by 1990 and Windows 3.0, Lotus and WordPerfect still stank.
That they bundled Word and Excel in 1989, whatever. The real innovation happened years before.
Interesting; things apparently regressed before they could progress. The first paper tape reader for a computer (Colossus) read at 5000 characters/s in normal operation, and could be cranked up to 9700 char/s (85 km/h), but the tape wasn't strong enough to survive that speed for long. Of course, the Official Secrets Act made sure the Colossus design wasn't available on the open market.
In my country, the police issue ca. 7 million speeding tickets each year. With around 7 million cars registered, every car owner gets one speeding ticket/year on average. To get this many tickets, speed is checked automatically and rigidly, with a margin of only 3% to allow for measurement errors. This means situational awareness is not enough to avoid speeding tickets. If you rely on situational awareness alone, you end up with a margin of 10% (more on motorways), which is just too much. Last year I bought my first car with cruise control. One of the big surprises was how much the cognitive load dropped from not having to constantly micromanage my speed and look out for speed cameras. My situational awareness improved (less time spent glancing at the speedometer).
That sucks. Over the past few years I've tripped over my Macbook's power cord several times with no ill effect. Back to watching where I'm going, I guess...
I recently read somewhere (but now can't find, of course) a study that indicated people are less likely to come up with creative solutions/leaps of thought in a noisy environment. This included listening to music.
Do you know how the Lego Minecraft set came to be? Mojang submitted a proposal to Lego Cuusoo (since renamed to Lego Ideas). On this site anyone can submit ideas for Lego sets, when an idea attracts 10,000 votes Lego will look into producing it as a set. We got some cool stuff that way: the Curiosity rover, for instance. The Minecraft set also got lots of votes, and the rest is history.
They did do a study that contradicts earlier experiments:
A person's natural circadian rhythm averages about 24 hours and six minutes for women, and 24 hours and 12 minutes for men. It varies for each individual, but doesn't stray very far from 24 hours. At about the time Pathfinder landed, Czeisler and his team began conducting studies at the hospital's special laboratory that shielded study subjects from all outside influences. With their test subjects in isolation, they simulated the Martian sol to see how the test subjects adjusted to the longer day. "What we learned was none of the people adapted their circadian rhythms to the Martian day," Czeisler said.
So either earlier studies were off, or Czeisler's experiment was wrong (having e.g. the HVAC on a 24-h cycle, or background noise etc.).
Living on Mars time is difficult when you're living on Earth and are subject to Earth's day/night cycle.
Sensory deprivation experiments where people live without clocks and daylight for more than a few days show that people tend to lengthen their "day" to much more than a Mars sol (up to 36 hours IIRC), indicating that adjusting to Mars time is feasible when you're actually on Mars.
That didn't work the last time. Remember the '80s? Oh, how we laughed at the KGB, Stasi et al. and their invasive ways. Listening to everybody, having half the population on the payroll and informing on the other half, reading all mail etc. How superior we felt, with our freedoms.
While I agree that the prefs interface could use improvement, please don't suggest they reduce the number of preferences. I use VLC because it's configurable to my tastes.
Slashdot Mirror
Even when I was growing up (in the 1950s) my first impressions of astronomy were formed by illustrations of the solar system--shown from a point of view outside the system, with the orbits displayed as brightly colored, ellipses ...
Now that would be cool; standing at a point where the ecliptic plane is right overhead, and seeing a bright red ribbon erupting from the ground, extending straight up as far as the eye can see. The eruption point would move at 1600 km/h and the ribbon itself would move up at 29 km/s. I'm so disappointed this doesn't happen :-)
The numbers gathered by the Nazis in WW2 agree with the numbers gathered after the war by people unsympathetic to the Nazis. How much more confirmation do you need before you cross the line from sceptic to denialist?
Troubling is that most everyone on the street will know what happened to Jews in WW2 if you ask.
In the Western world, maybe. Denying the Holocaust is still a popular pastime in e.g. the Arabic world.
London Pneumatic Dispatch Company or London Post Office Railway
There's still an option to allow exact searches: Search tools->all results->Verbatim.
Drives me nuts too, I'll have to figure out how to specify that in the URL so I can at least call the page with that option already switched on.
You can see the RCS in action in this video
At first glance, it would seem that a circular orbit can still lead to varying tidal forces. The only requirement is that the planet is not tidally locked to the moon (i.e. the planet's rotation is not in sync with the moon's orbit). Or am I overlooking something?
The recoverable version (F9R) has a set of cold gas thrusters. Other than that, not much is known. See this page
I'd be really "easy" to land if they had an RCS, just a couple seconds worth to cancel out any lateral movements and rotations
In its current configuration, the stage can't hover: on its lowest thrust setting, the engine still provides too much thrust. So they land using a "hoverslam" maneuver where they try to decelerate to a vertical speed of 0 just as the stage intersects the barge.
There is an RCS at the top of the stage to keep the stage upright, but any lateral thrust at the bottom has to be done by gimbaling the main engine. The gimbaling angle is limited so they may have run out of control authority on this landing.
The only thing you can remotely call a "day" on the ISS is about 90 minutes long.
The astronauts are on a 24-hour work/sleep cycle. It may not have anything to do with sunrises and sunsets anymore (1), but is there any reason other than extreme pedantism to not call that cycle a day?
1: other than the sunrises and sunsets over the control centers in Houston and Moscow.
An extended play tape cassette could store 3 hours of audio per side
I'm sorry, a what now?
The Compact Cassette standard had one tape speed (4.76 cm/s). Readily available cassettes came with 60-minute or 90-minute runtimes (total). You could get C-120 cassettes with 1 hour per side, but those used extra-thin tape that jammed easily. The longest tapes ever made were C-180, for 90 minutes per side, these used even thinner tape and so unreliable they never sold widely.
I've never seen one, and I was a bit of an audiophile in those days.
You'd have to combine a C-180 tape with a non-standard playing speed (used only in dication machines) to get 3 hours per side.
But Esperanto hasn't succeeded, so we'd need a new language loosely based on it. Let's call it....
Esperanto++
Excel (first introduced on the Mac in 1985) was a huge step forward from Lotus 1-2-3. Word (first graphical version also on the Mac in 1985) blew WordPerfect right out of the water.
Developing these for the Mac gave Microsoft a taste of what a GUI could do, which was much more than Lotus and WordPerfect were doing with their crappy GUIs grafted onto CLI programs. Even by 1990 and Windows 3.0, Lotus and WordPerfect still stank.
That they bundled Word and Excel in 1989, whatever. The real innovation happened years before.
Interesting; things apparently regressed before they could progress. The first paper tape reader for a computer (Colossus) read at 5000 characters/s in normal operation, and could be cranked up to 9700 char/s (85 km/h), but the tape wasn't strong enough to survive that speed for long.
Of course, the Official Secrets Act made sure the Colossus design wasn't available on the open market.
In my country, the police issue ca. 7 million speeding tickets each year. With around 7 million cars registered, every car owner gets one speeding ticket/year on average. To get this many tickets, speed is checked automatically and rigidly, with a margin of only 3% to allow for measurement errors.
This means situational awareness is not enough to avoid speeding tickets. If you rely on situational awareness alone, you end up with a margin of 10% (more on motorways), which is just too much.
Last year I bought my first car with cruise control. One of the big surprises was how much the cognitive load dropped from not having to constantly micromanage my speed and look out for speed cameras. My situational awareness improved (less time spent glancing at the speedometer).
That sucks. Over the past few years I've tripped over my Macbook's power cord several times with no ill effect. Back to watching where I'm going, I guess...
I recently read somewhere (but now can't find, of course) a study that indicated people are less likely to come up with creative solutions/leaps of thought in a noisy environment. This included listening to music.
Do you know how the Lego Minecraft set came to be? Mojang submitted a proposal to Lego Cuusoo (since renamed to Lego Ideas). On this site anyone can submit ideas for Lego sets, when an idea attracts 10,000 votes Lego will look into producing it as a set. We got some cool stuff that way: the Curiosity rover, for instance. The Minecraft set also got lots of votes, and the rest is history.
Damn you for making me read the entire FA ;-/
They did do a study that contradicts earlier experiments:
A person's natural circadian rhythm averages about 24 hours and six minutes for women, and 24 hours and 12 minutes for men. It varies for each individual, but doesn't stray very far from 24 hours. At about the time Pathfinder landed, Czeisler and his team began conducting studies at the hospital's special laboratory that shielded study subjects from all outside influences. With their test subjects in isolation, they simulated the Martian sol to see how the test subjects adjusted to the longer day. "What we learned was none of the people adapted their circadian rhythms to the Martian day," Czeisler said.
So either earlier studies were off, or Czeisler's experiment was wrong (having e.g. the HVAC on a 24-h cycle, or background noise etc.).
Living on Mars time is difficult when you're living on Earth and are subject to Earth's day/night cycle.
Sensory deprivation experiments where people live without clocks and daylight for more than a few days show that people tend to lengthen their "day" to much more than a Mars sol (up to 36 hours IIRC), indicating that adjusting to Mars time is feasible when you're actually on Mars.
That didn't work the last time. Remember the '80s? Oh, how we laughed at the KGB, Stasi et al. and their invasive ways. Listening to everybody, having half the population on the payroll and informing on the other half, reading all mail etc.
How superior we felt, with our freedoms.
Now look where we are.
While I agree that the prefs interface could use improvement, please don't suggest they reduce the number of preferences. I use VLC because it's configurable to my tastes.
Decent RJ45 cables come with a sleeve that fits over the tab. This should have been mandatory instead of an option.
Passive amplifiers are perpetual motion machines. An echo chamber doesn't amplify, it merely minimizes attenuation.
Do I understand the difference correctly? Transponder = optical receiver, processing equipment and laser which sends a new signal. Amplifier = EDFA?