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Saturday, May 17, 2008

New observations show that if life exists on Mars, it's probably going to be much deeper underground than expected

Life on Mars Theories Take a Hit
New observations show that if life exists on Mars, it's probably going to be much deeper underground than expected Scientists have posited that if life exists on Mars presently, it is probably hidden out of view in aquifers beneath the planet's barren surface. Unfortunately, new data collected by NASA's Mars Reconnaissance Orbiter suggests that these aquifers, if they exist, are probably much deeper inside the small ruddy planet than researchers had hoped.Using the orbiter's SHARAD (Shallow Radar) instrument, scientists have been able to get a very detailed picture of Mars' nothern global icecap and the planet's crust below. Though the data has proven very useful in fleshing out the life cycle of the giant ice cap, it also shows that the martian lithosphere, or the outer crust, is very stiff.Earth's lithosphere, in contrast, is somewhat soft. A large buildup of ice on Earth in a situation similar to Mars' would actually cause the crust to sag beneath its weight. On Mars, this is not happening. Scientists believe this shows that Mars' lithosphere is quite thick and cold.Warmed internally by pressure and/or an active core, a planet's lithosphere gradually grows colder towards the outside. Mars' lithosphere being stiff enough to not sag under the immense weight of its icecaps indicates that the any warmth generated internally does not venture far from the core, making the outer crust much colder than anticipated. This cold would prevent liquid water from forming anywhere near the surface. Instead, should it exist, it would be much deeper and most likely inaccessible by any easy means.The Mars Reconnaissance Orbiter's detailed imaging of the icecap did show evidence for a planetary climate, however. Alternating layers of dusty ice and nearly pure ice are thought to show a timetable of approximately one million year intervals. This coincides with the estimate that the cap itself is roughly four million years old. The climate changes are likely caused by variations in the planet's rotational axis and orbit.More surface data from the northern polar region should be available very soon as NASA's Phoenix Mars Lander is slated to set down on the planet's surface in just over a week. The lander will explore the polar region and look for signs of the existence of water on the surface in the past.

Microsoft: Don't Misunderstand UAC

Microsoft: Don't Misunderstand UAC, Other Vista Features
In its continued attempt to convince business customers to adopt Vista, Microsoft has outlined and tried to explain some of what it calls the OS's most "misunderstood" features in a document posted to -- then mysteriously removed from -- its Web site this week.
In the document, "Five Misunderstood Features in Windows Vista," Microsoft lists what it believes are five features of Vista that "cause confusion" and "slow Windows Vista adoption" for most users. The company identified User Account Control, Image Management, Display Driver Model, Windows Search and 64-bit architecture as features that are flummoxing IT professionals when they install Vista across desktops on a network. It offered tips for how to deal with common problems.
The document was posted to the Web site Friday morning; however, by the afternoon, the link was no longer working. It still came up in a Live Search of the Microsoft Web site, but the link provided there also was inactive.
Microsoft did not immediately respond to a request about the document Friday.
Businesses have been slow to adopt Vista since its enterprise introduction in late November 2006, and by now users have identified the features listed in the document as some of their biggest pain points.
One that has been especially problematic -- and even spoofed in an Apple TV commercial -- is User Account Control (UAC). UAC prevents users without administrative privileges from making unauthorized changes to a PC. But because of its settings, it can prevent even authorized users on the network from being able to access applications and features they should normally have access to. It does this through a series of screen prompts that ask the user to verify privileges, and it may require a user to type in a password to perform a task.
In its document, Microsoft said the feature has gotten a "bad rap" because it's a "set of technologies" dispersed throughout the OS and designed to protect the system in a variety of ways, not just one feature that can be controlled in an isolated way.
Microsoft also designed UAC to "help nudge ISVs towards designing applications that function in Standard User mode," one of two user privilege modes in UAC. The other is Local Administrator.
As it stands now, the prompts interrupt normal workflow, even in some mundane tasks, unless a user is set as Local Administrator. This is because the many third-party Windows applications that predate Vista weren't developed to work with UAC's "Standard User" designation, so they default to requiring Local Administrator rights, said Keith Brown, a network administrator for Gwinnett Medical Center in Lawrenceville, Georgia. Gwinnett is a not-for-profit medical network serving more than 700 physicians around the Atlanta area.
If a Standard User asks an application to perform a task that touches a part of the OS that the software says "should not be meddled with," it will prompt the user and require a password to perform that task, he said. This is common, especially when someone tries to install software as a Standard User, Brown said.
"It's an annoyance," he said, which is why most IT administrators will turn off the feature when installing Vista across desktops, which defeats the purpose of Microsoft putting it in to protect the OS in the first place.
One way to get around UAC is to use third-party software, such as Privilege Manager from BeyondTrust, to set user privileges, Brown said. Microsoft even recommended BeyondTrust's product to customers when the company, based in Portsmouth, N.H., came out with Privilege Manager 3.5 last August. That was the first version of the product designed to work with UAC.
John Moyer, CEO of BeyondTrust, said Privilege Manager lets network administrators configure in advance which applications can run or be installed on Vista machines on a network. It assigns the appropriate elevated privileges to Standard Users so they are not prompted even if third-party software does not recognize them as an authorized user of a task. "There is no interruption to the workflow," he said.
Brown said that without Privilege Manager, UAC would probably be turned off for the 30 to 40 Vista desktops his company is testing in its information systems department. He said the incessant prompting from UAC can be turned off from within Vista, but it's extremely time-consuming for the IT department to do that for each user on the network.
Gwinnett Medical Center eventually is planning a broader Vista deployment, but that "won't be this year," Brown added.


One wonders, with all of the 'misunderstandings' Vista has generated with people, whether Microsoft would be best served by pushing it, or hyping XP's SP3, withdrawing the kill date for it and letting end users continue to install it (and OEM's to offer it) until at least after the release of Windows 7. XP didn't have this much trouble a year and a half after its release. It was clearly superior to Win 98. The clarity of superiority of Vista to XP is utterly missing insofar as speed, productivity, implementation and hardware costs go. We won't even talk about DRM's or other under the hood things that allows MS to turn you off like a light switch in Vista. People who understand the issues clearly don't want Vista as much as XP. And if Microsoft insists on forcing XP on us, I expect more and more users will turn to Linux. At least with Linux, you expect different - and it costs a lot less. If we can't have XP, we'll take something less expensive and with fewer issues.

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