sciencehabit writes: By taking more than 70 million observations during its first 2 years in orbit, a limousine-length satellite has given scientists their most detailed map yet of Earth's gravitational field. The lumpiness of that geoid—the theoretical surface that a planet-wide ocean would take if there were no tides or currents—betrays the irregularity of the planet's mass distribution, including concentrations of mass such as mountain ranges and ice sheets. The work could lead to better understanding of the speeds and paths of ocean currents, as well as improved estimates of how they disperse pollutants. It could also provide new insights about geological processes occurring deep within Earth, such as the movement of one tectonic plate being shoved beneath another, and when combined with other data will help improve estimates of the thickness and mass of polar ice sheets.
Hugh Pickens writes writes: "The Register reports that the majority of the communications between convicted terrorist Rajib Karim and Bangladeshi Islamic activists were encrypted with a system which used Excel transposition tables which they invented themselves that used a single-letter substitution cipher invented by the ancient Greeks that had been used and described by Julius Caesar in 55BC. Despite urging by the Yemen-based al Qaida leader Anwar Al Anlaki, Karim rejected the use of a sophisticated code program called "Mujhaddin Secrets" which implements all the AES candidate cyphers, "because 'kaffirs', or non-believers, know about it so it must be less secure." "Tough communication interception laws [RIPA] were passed in the UK 10 years ago on the basis that they were needed to fight terrorism," says Duncan Campbell, who acted as an expert witness for the defense during the trial. "The level of cryptography they used was not even up to the standards of cryptology and cryptography in the Middle Ages, although they made it look pretty using Excel.""
1sockchuck writes: Today is World Backup Day, an occasion to backup your personal data and financial information and check your restores. For those needing motivation — a group that apparently includes 15 percent of data centers — the Slashdot archives bear witness to date disasters at providers small (Ma.gnolia) and large (Microsoft). The World Backup Day initiative grew out of a thread at Reddit, and invites online backup services to observe the occasion by offering discounts.