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5 millenni di eclissi solari

Geek   21.07.17  

Un database di eclissi solari.

During the 5,000-year period from -1999 to +3000 (2000 BCE to 3000 CE), Earth will experience 11,898 eclipses of the Sun. The statistical distribution of eclipse types for this interval is as follows : 4,200 partial eclipses, 3,956 annular eclipses, 3,173 total eclipses and 569 hybrid eclipses. All the data accessed through this interface is provided by Fred Espenak and Jean Meeus (NASA Technical Publication TP-2006-214141). The data available is described in greater detail in the Key to Solar Eclipse Catalogs.

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La programmazione nel 2017

Geek   20.07.17  

Un'indagine sull'uso dei linguaggi di programmazione del 2017. Un contenitore di open data per stilare classifiche sullo stato della programmazione in continua evoluzione, dalle app ai desktop, dal web ai server.

This app ranks the popularity of dozens of programming languages. You can filter them by listing only those most relevant to particular sectors, such as "Web" or "embedded programming." Rankings are created by weighting and combining 12 metrics from 10 sources. We offer preset weightings—the default is our IEEE Spectrum ranking—but there are presets for those interested in what's trending or most looked for by employers. Don't like the defaults? Take complete control and create your own ranking by adjusting each metric's weighting yourself. To compare with a previous year's data, click "Add a Comparison" and then click "Edit Ranking," which will give you the option to compare with data from 2014, 2015, or 2016.

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Centinaia di numeri di Galaxy Science Fiction gratis online

Geek   15.07.17  

L'archivio dal 1950 al 1976 di Galaxy Science Fiction, una delle migliori riviste di fantascienza di tutti i tempi, è disponibile gratuitamente su Archive.org.
Fahrenheit 451 di Ray Bradbury, L'uomo disintegrato di Alfred Bester, Abissi d'acciaio di Isaac Asimov, Il terrore dalla sesta luna di Robert A. Heinlein, solo per citare alcuni capolavori disponibili in questa raccolta.

The collection contains 355 separate issues, ranging from 1950 through 1976. Open Culture notes that it's not quite the entire run of the magazine, but it's got plenty of material to keep fans occupied for years. It includes stories from science fiction legends such as Isaac Asimov, Robert A. Heinlein, Clifford Simak, and Theodore Sturgeon. There are also some underappreciated authors who deserve re-discovery, such as Kris Neville, Alan E. Nourse, or John Christopher.

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Come è cambiato negli anni iOS

Geek   01.07.17  

9To5Mac ripercorre l'evoluzione di iOS, dal 2007 a iOS 10, in attesa della versione stabile di iOS 11.

Introduced alongside the first-generation iPhone in 2007, the then-called iPhone OS was the basis of Apple’s first smartphone and its goal to introduce "a revolutionary product that changes everything."

10 years later, the iOS has evolved just as much as the iPhone hardware has, if not more. Head below as we take a look at the progression of iOS over the years...

When Steve Jobs originally unveiled the iPhone at the Macworld Conference & Expo on January 9, 2007, he proclaimed the iPhone ran "real Mac OS X" and was capable of running "desktop applications." Fast forward a few months and the iPhone operating system had been renamed to just iPhone OS, and thus the introduction of iPhone OS 1.

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La nascita di iPhone tra passi falsi e successi

Geek   30.06.17  

A 10 anni dalla presentazione del primo iPhone, il Wall Street Journal ha intervistato Scott Forstall, Greg Christie e Tony Fadell per farsi raccontare i primi passi verso la creazione di uno dei prodotti più venduti nella storia.

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Elon Musk e la colonizzazione di Marte in dettaglio

Geek   15.06.17  

Su New Space si possono leggere le linee guida dell'ambizioso progetto di Elon Musk per colonizzare Marte con costi e tempi ragionevoli.

The rocket booster and the spaceship take off and launch the spaceship into orbit. The rocket booster then comes back quite quickly, within about 20 minutes. So, it can actually launch the tanker version of the spacecraft, which is essentially the same as the spaceship but filling up the unpressurized and pressurized cargo areas with propellant tanks... Then, the propellant tanker goes up anywhere from three to five times to fill the tanks of the spaceship in orbit. Once the tanks are full, the cargo has been transferred, and we reach the Mars rendezvous timing, which is roughly every 26 months, that is when the ship would depart... Over time, there were would be many spaceships. You would ultimately have upwards of 1,000 or more spaceships waiting in orbit. Hence, the Mars Colonial fleet would depart en masse.

[...] The threshold for a self-sustaining city on Mars or a civilization would be a million people. If you can only go every 2 years and if you have 100 people per ship, that is 10,000 trips. Therefore, at least 100 people per trip is the right order of magnitude, and we may end up expanding the crew section and ultimately taking more like 200 or more people per flight in order to reduce the cost per person. However, 10,000 flights is a lot of flights, so ultimately you would really want in the order of 1,000 ships... it would take 40–100 years to achieve a fully self-sustaining civilization on Mars.

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