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Scientists suggest Mars still has an active underground water system – CNET

NASA/JPL/University of Arizona First we learned that Mars may be hiding a lake under its southern ice cap. Now a new study points to an active groundwater system that may be lurking deep below the planet’s equatorial regions, feeding a mysterious phenomenon on the Martian surface.  If the study holds water, it would be a…

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Scientists suggest Mars still has an active underground water system     – CNET

NASA/JPL/University of Arizona
First we learned that Mars may be hiding a lake under its southern ice cap. Now a new study points to an active groundwater system that may be lurking deep below the planet’s equatorial regions, feeding a mysterious phenomenon on the Martian surface. 
If the study holds water, it would be a huge paradigm shift for the dusty, barren planet. And it could open up new avenues of exploration. 
Two researchers at the University of Southern California, Abotalib Z. Abotalib and Essam Heggy, posit that “recurring slope lineae” (RSL), dark streaks that periodically appear on the side of Martian craters, are being created by an active, deep reservoir of salty water.   
The study, published Thursday in Nature Geoscience, used images provided by HiRISE, a high-resolution camera aboard the NASA’s Mars Reconnaissance Orbiter circling the red planet, to analyze distinct surface features. 
The duo examined images of Palikir crater, which has previously been shown to harbor RSL and is a prime location for present-day water flows, to come up with their new hypothesis. They discovered that RSL most commonly emanate from fractures and cracks in Palikir’s surface. 
“Mars is not hydrologically dead,” says Heggy. “There is an active groundwater system on Mars that is causing the recurring slope lineae.”

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In the past scientists, have hypothesized a number of reasons the RSL appear on the side of Martian craters, including the idea that they may just be sand flows rather than a phenomenon caused by water. Other groups have suggested they’re caused by seeping salt water that originates from just below the surface. However, radar experiments imaging the Martian surface have not been able to identify any shallow pools of groundwater.
Heggy and Abotalib’s background, studying aquifers and groundwater flow in Earth’s desert environments, prompted them to look at the Mars RSL hypothesis from another angle — and they began to see similarities with our planet’s deserts. Their proposal suggests that the water originates from about half a mile below the surface (approximately 750 meters) and that high pressure forces the liquid up through the soil and eventually through cracks and fractures on the surface — resulting in the RSL.
“We have seen the same mechanisms in the North African Sahara and in the Arabian Peninsula, and it helped us explore the same mechanism on Mars,” says Abotalib.
An important feature of the Mars’ RSL is seasonality. Typically, they appear during the Mars summer and disappear in the fall. Heggy suggests that in the fall, when it’s cooler, the water freezes over the fractures, preventing the RSL from forming. In summer, warm weather allows the pressurized water to flow up and out through the cracks, seeping down the slopes.
But with all this high-resolution imaging, why haven’t we spotted the liquid flows before?

“They last for a very short amount of time due to the condition of the surface and pressure on Mars,” explains Heggy. “We don’t have sufficient temporal coverage on Mars to witness that happen in real time.”
The tantalizing prospect of water on Mars has long been discussed and researched because of the opportunities it presents to discover life or provide a means for colonization. But for Heggy, this study is less about proving Mars is somewhere humans may one day set up shop and more about our own planet. 
“Water on Mars is very important, not to colonize Mars, but to understand how our own planet is evolving,” he says. “The importance of groundwater is never about using it as a sustainable resource for humans on Mars.”
The mystery of the Mars’ RSL now has another viable theoretical candidate, but there’s still work to be done. NASA Mars rover Curiosity has been exploring regions close to where the RSL form but has not studied them, and direct evidence of an active groundwater system still eludes areologists. Heggy and Abotalib will focus on rectifying that.
“We’re going to be trying to see what are the best ways to find direct evidence or map these groundwater systems, potentially using future probing experiments,” he says.   
It’s been a bumper year for Mars water discoveries. In February, researchers at the University of Utrecht suggested they’d discovered evidence that a deep groundwater system had once existed on Mars, given the features they’d observed in craters. On Wednesday, scientists from the University of Chicago suggested that rivers still raged less than 1 billion years ago. 
With NASA and the European Space Agency sending rovers to Mars in 2020 — and researchers scouring the planet for signs of groundwater — it might not be long before we have definitive evidence that Mars isn’t as dry as we once thought. 

Originally published 9 a.m. PTUpdated 2:10 p.m. PT: Adds Nature Geoscience paper

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LEGO Star Wars Millennium Falcon for $135 + free shipping – CNET

Web Hosting & Services Solutions Your destination for all things hosting and more! Find the best providers, plans and deals, learn what you need to know to build your web presence and optimize your site. Use our comparison tools and speed test, get support in our forums and much more. Learn more!

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LEGO Star Wars Millennium Falcon for $135 + free shipping     – CNET

Web Hosting & Services Solutions

Your destination for all things hosting and more!

Find the best providers, plans and deals, learn what you need to know to build your web presence and optimize your site. Use our comparison tools and speed test, get support in our forums and much more.

Learn more!

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Amazon Echo Show 8 review: The best Alexa smart display, period – CNET

It’s 2020 and the Echo Show 8 is a year old. But Amazon’s fourth Alexa-enabled smart display still stands apart from the competition as one of the best smart devices around. Squeezed between its high-end 10-inch and budget 5-inch siblings, the Show 8 offers the right mix of features and design perks to justify its middle-child…

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Amazon Echo Show 8 review: The best Alexa smart display, period     – CNET

It’s 2020 and the Echo Show 8 is a year old. But Amazon’s fourth Alexa-enabled smart display still stands apart from the competition as one of the best smart devices around. Squeezed between its high-end 10-inch and budget 5-inch siblings, the Show 8 offers the right mix of features and design perks to justify its middle-child existence — and it’s the best direct competitor to Google’s Nest Hub. Even a year out from its release, the Echo Show 8 still deserves its Editors’ Choice Award.

LikeThe Echo Show 8 has solid sound quality and a good screen resolution.The $130 price tag makes the Show 8 one of the best midrange smart displays on the market.The physical camera shutter is a small, smart addition to soothe privacy concerns.

Don’t LikeThe interface isn’t as smooth or easy to use as the one on Google’s Nest Hubs.You can’t call up YouTube videos by voice.

If you’re thinking of buying a smart display for your countertop, the Show 8 might just be the best product for the price. Its full $130 price tag is a solid deal, but the frequent discounts (the current US price is only $65; in the UK its £120 price is currently discounted to £90) make it even more attractive. 
Chris Monroe/CNET
Fitting in with the crowd Last year, Amazon filled out its smart speaker and display product lines with nearly a half-dozen new devices, including the Amazon Echo, Echo Dot with Clock, Echo Studio, Echo Show 5 and Show 8. There is a clear pattern: Each product line has a papa bear, mama bear and baby bear option. Amazon is hoping one of these devices will be just right for you. In 2020, that pattern has remained largely intact, though the Echo and Dot both received sphere-shaped redesigns — and a redux for the 10-inch Echo Show is on the horizon.

Echo’s line of smart displays doesn’t just add dumb screens to smart speakers. These devices equip the voice assistant Alexa with video chatting and streaming, they work with Ring doorbells and Wyze Cams to let you see what’s happening at your front door, they can provide cooking assistance in the kitchen (read more about Amazon’s partnership with Food Network to bring lessons from professional chefs to your kitchen) and they even offer touch controls for the smart home. For $130 (£120) or less, the Echo Show 8 really does pack in a lot of useful smarts.
Third thought, best thought Critics might argue that the Echo Show 8 doesn’t bring any new features to the countertop. That’s true, but as with Amazon’s best recent products, the Show 8 is less about grand innovation than smart iteration. The Show 8 brings more heft than the Show 5 (which is cheaper by $40): a screen that’s bigger than a propped-up phone, fairly sharp 1,280×800-pixel resolution and a pair of solid 2-inch speakers. What’s more, the Show 8 steals the Show 5’s best ideas, like the physical camera shutter and sunrise alarms (although for some reason, Amazon didn’t include the 5’s tap-to-snooze feature).

I particularly like the shutter. The second-gen Echo Show ($150 at Amazon) doesn’t have any design feature to disconnect the camera. While Google opted for a kill switch for the camera and microphone on the Nest Hub Max ($229 at Sam’s Club), Amazon has included a physical shutter on its last two displays. From a privacy standpoint, I’m a fan of Amazon not just saying, “Trust me, it’s fine.” I can look at the Show 8, see that the shutter is closed and be 100% certain that I’m not being watched.
Chris Monroe/CNET
Another smart touch is that the screen, while sporting the same resolution as the 10-inch Show from 2018, uses a new feature to improve the image quality over that larger display. While images won’t appear any sharper (other than by merit of the pixel count on the smaller display), progressive scanning means fewer visual artifacts will appear on the screen. It’s an addition few casual users will notice day to day, but it’s a useful quality-of-life upgrade that you’ll feel over time. Talking to myself While the Show 8 is a clear upgrade from its predecessors, it seems to fall short in one big area: The camera is only 1 megapixel, as opposed to the 5-megapixel camera on the second-gen Show. Lower-megapixel cameras generally produce blurry results, and honestly, I was taken aback when I heard that spec.
Chris Monroe/CNET
But when I video-hatted with myself using the second-gen Show and the Show 8, the feed from the 5-megapixel camera actually looked more pixelated than the one captured by the lower-quality cam. Whatever the reason, the lower-quality camera, in this case, produced consistently higher-quality results for me. The bottom line is this: The extra $100 for the Echo Show isn’t necessarily going to translate to higher video-chat image quality, so that 1-megapixel camera shouldn’t dissuade you from opting for the cheaper Show 8 instead. Keeping an ear to the counter When it comes to sound quality on the Echo Show 8, you might be pleasantly surprised. The two 2-inch speakers are a little smaller than the 2.2-inch speakers in the 10-inch Show, and you can hear the slight difference in sound quality, especially at higher volumes. When you push it, the Show 8 starts sounding a little buzzy, and it doesn’t have the range and distinction of the Echo stand-alone speaker or the 10-inch Echo Show’s. But the Echo Show 8’s sound quality is much better than that of the more diminutive Show 5, which has only a single 1.7-inch speaker. In fact, set side by side with the latest Amazon Echo smart speaker, the Show 8 produces somewhat similar results — as long as you keep the volume in the middle of its range.
Chris Monroe/CNET
Alexa and the screen Despite not having the Zigbee receiver from the second-gen Show or the tap-to-snooze feature of the Show 5, the Show 8 might be the best Alexa-enabled smart display. But that doesn’t mean it’s the best display altogether. While I like the combination of clever features — and, as importantly, the price tag attached to them — Google’s smart displays do boast a better user experience. It’s tough to compare the Show 8 directly with the Nest Hub — Google’s $90 7-inch display — because that doesn’t even have a camera. And the Nest Hub Max, which does include a high-quality camera, costs $230. But one thing both Nest Hubs share is a smoother interface than the Echo Show 8’s. The screen is more responsive, the camera can follow your face if you walk around while video chatting and you can access videos on YouTube with a simple voice command. Amazon’s operating system is improving, but compared with Google’s, it still lags — a jarring experience if you’re accustomed to the responsiveness of modern smartphones and tablets. In addition, with another Echo Show on the way — this time a 10-inch display that will physically turn to follow you around the room — some users may want to hold off on getting the Show 8. But the Show 10 will likely clock in at a whole different price level, so if you’re looking for more budget-friendly displays, you can’t go wrong with the Show 8. If you are looking for a more premium machine, you may want to wait for the Show 10. These minor qualifiers aside, I’m happy to recommend the Show 8. For $130 (or as little as $65), it’s the smartest Amazon display for the price. It combines the best of the rest and has a cam and better sound quality than the Nest Hub.

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WD My Passport SSD (2020) Review

WD’s latest round of redesigns has spread throughout its portable storage lineup, replacing the bold, bright, sharp design-led identity with rounded edges, muted colours, and simpler plastic bodies. Whimsy has given way to practicality, which you might or might not be in favour of. The latest reimagined storage device is the WD My Passport SSD…

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WD My Passport SSD (2020) Review

WD’s latest round of redesigns has spread throughout its portable storage lineup, replacing the bold, bright, sharp design-led identity with rounded edges, muted colours, and simpler plastic bodies. Whimsy has given way to practicality, which you might or might not be in favour of. The latest reimagined storage device is the WD My Passport SSD (2020), but in this case, the changes aren’t solely cosmetic. You get a huge bump in hardware specifications and speeds, keeping WD’s portable SSD lineup current and competitive. Here’s a review of the brand new WD My Passport SSD (2020).WD My Passport SSD (2020) design and featuresThe older two-tone metal-and-plastic design might have been slightly impractical with its sharp corners and overall bulk, but it looked and felt very modern and premium. Now, you get a much more organic body, shaped somewhat like a thin bar of soap. It’s much flatter than before, with rounded sides and corners that make for an easy grip. This device will be comfortable in your hand as well as your pocket. It weighs only 45.7g.The body is made of metal and there’s a swirly ridged pattern on the front as well as the rear. The USB Type-C port is off-centre on the bottom and there’s no activity LED. The raised WD logo feels rough and looks rather garish, but otherwise this is a simple, sober design that will fit in anywhere. You have a choice between Space Grey, Midnight Blue, and Gold. A red version appears to be available in other countries, but isn’t listed here.The WD My Passport SSD (2020) weighs 45.7g Unlike some other portable SSDs (including models from Western Digital’s other brands, SanDisk and G-Technology), there’s no waterproofing or other form of protection from the elements. WD does mention shock and vibration resistance, which are inherent to SSDs, plus drop resistance for falls from up to 1.98m in height.Perhaps unsurprisingly, the My Passport SSD (2020) is very similar in shape and size to the SanDisk Extreme V2 portable SSD, but doesn’t have an integrated handle, ruggedised coating, or IP rating.You get a very short USB Type-C cable in the box, with a Type-C to Type-A adapter for broad compatibility. As we noted with the previous incarnation of the My Passport SSD, such an adapter is technically outside the official USB specification and so the cable and adapter both have notches to make sure they’re used with each other. That doesn’t physically stop you from using the entire cable, plus adapter, with another device though. This should be avoided, because some devices need to negotiate things like how much power is sent from one side to another, which cannot happen through a legacy USB port when such an adapter is used.WD My Passport SSD (2020) price, specifications and performanceThe biggest upgrade comes from the use of an NVMe SSD and bridge rather than the older SATA protocol. WD claims read and write speeds of 1050MBps and 1000MBps respectively – exactly the same as the Samsung SSD T7 Touch, and in line with the Sandisk Extreme Pro. You’ll need a PC with a USB 3.2 Gen2 (10Gbps) or Thunderbolt 3 port to be able to harness such speed.The new My Passport SSD (2020) is available in 500GB, 1TB and 2TB capacities, priced officially at Rs. 8,999, Rs. 15,999, and Rs. 28,999 respectively. They are exclusive to Amazon during the festive sale period, and actual prices are quite a bit lower. They will be available offline from mid-November. There’s a USB Type-C port on the bottom but no status LED WD has implemented 256-bit AES hardware encryption. The company offers quite a lot of free software that you can download, including the capable Drive Utilities for general maintenance, WD Backup to set up simple backup routines, and WD Security to set up encryption with a password. You’re also encouraged to install WD Discovery, which is completely unnecessary and only exists to serve up ads and promotions for WD.The 1TB review unit we’re testing today was formatted to exFAT by default. This works cross-platform, but if you’re planning to use Time Machine on a Mac, you’ll need to reformat the drive to HFS+ (or at least partition and format some of it). Windows’ Disk Management console reported 931.48GB of usable space.All tests were run on an HP Spectre x360 13 laptop because of its Thunderbolt 3 ports. CrystalDiskMark 6 reported sequential read and write speeds of 913.9Mbps and 924.9Mbps respectively, which is not too far below WD’s official claim. More realistic random read and write speeds were 154.1Mbps and 163.8MBps respectively. While good by portable SSD standards, the My Passport SSD (2020)’s scores lag quite a way behind what the Samsung SSD T7 Touch and SanDisk Extreme Pro were able to achieve. The Anvil benchmark managed read and write scores of 2,186.6 and 1,921.12, for an overall score of 4,107.72.The shell of the WD My Passport SSD (2020) did get quite warm when benchmarks were running and when large batches of files were being copied up and down in testing. This shouldn’t be much of a problem in everyday use, and there’s nothing else to complain about.You get a small USB Type-C cable with a Type-A adapter VerdictIf you like bold, edgy design and products that make a statement, the new WD My Passport might be a bit of a disappointment. It looks unassuming and pedestrian compared to its predecessor; more like a bar of soap than a high-end tech product. Perhaps this is a signifier that portable SSDs aren’t just lifestyle accessories for only those who can afford them anymore, but are now perfectly mainstream commodity products.The emerging new class of NVMe portable SSDs brings nearly twice the speed of previous-gen SATA models. Samsung still has the performance advantage, but WD isn’t too far behind now. Other than speed, you should choose your SSD based on whether you prioritise features such as AES encryption and ruggedisation. SSDs are also routinely discounted below their official MRPs, so if you do find a great deal on the WD My Passport SSD (2020) and it meets your requirements, you shouldn’t hesitate to pick one up.WD My Passport SSD (2020)Price (MOP): Rs. 6,999 (500GB)Rs. 12,999 (1TB)Rs. 24,999 (2TB)ProsNVMe-based, good read and write speeds  Good value for money Compact and lightConsGets a bit warm when stressed No IP ratingRatingsPerformance: 4.5 Value for Money: 4.5 Overall: 4.5

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