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Comment: Re:misquote (Score 2) 117

by hackertourist (#49477209) Attached to: SpaceX Dragon Launches Successfully, But No Rocket Recovery

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.

Comment: Re:Can we have this summary in English, please? (Score 1) 108

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.

Comment: Re:C64 had a cassette drive (Score 1) 74

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.

Comment: They list Office instead of Excel and Word? (Score 1) 142

by hackertourist (#49405623) Attached to: Microsoft Celebrates 40th Anniversary

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.

Comment: Re:Ah, PDP8 (Score 1) 92

by hackertourist (#49360141) Attached to: Rebuilding the PDP-8 With a Raspberry Pi

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.

Comment: Re:Good points, bad points (Score 1) 287

by hackertourist (#49334187) Attached to: Ford's New Car Tech Prevents You From Accidentally Speeding

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).

Comment: Re:I'd expect lots of cross-over branding crap (Score 1) 208

by hackertourist (#49179045) Attached to: What Would Minecraft 2 Look Like Under Microsoft?

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.

Never say you know a man until you have divided an inheritance with him.