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Comment: Re:Enhanced images have always had a downside (Score 1) 28

by hackertourist (#49544099) Attached to: How False Color Astronomy Works

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 :-)


Google Sunsetting Old Version of Google Maps 208

Posted by timothy
from the nothing-beats-mapblast's-vector-directions dept.
New submitter Robertgilberts writes with word that Google is dropping the old version of Maps. The new version of Google Maps came out of preview back in February 2014 and was in beta for several months before that. The only way to access the old version of Google Maps was via a special URL or if you had a very old browser that did not support the new version of Google Maps. Consolation prize: There will still be a lighter-weight version, which "drops out many of the neat Google Maps features in exchange for speed and compatibility."

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.


Inexpensive Electric Cars May Arrive Sooner Than You Think 330

Posted by timothy
from the I'll-take-it dept.
catchblue22 writes According to an article in MIT Technology Review, a new peer reviewed study suggests that battery-powered vehicles are close to being cost-effective for most people: "Electric cars may seem like a niche product that only wealthy people can afford, but a new analysis suggests that they may be close to competing with or even beating gas cars on cost. ... The authors of the new study concluded that the battery packs used by market-leading EV manufacturers like Tesla and Nissan cost as little as $300 per kilowatt-hour of energy in 2014. That's lower than the most optimistic published projections for 2015, and even below the average published projection for 2020. The authors found that batteries appear on track to reach $230 per kilowatt-hour by 2018. The authors found that batteries appear on track to reach $230 per kilowatt-hour by 2018. If that's true, it would push EVs across a meaningful threshold."

There are no data that cannot be plotted on a straight line if the axis are chosen correctly.