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GPS on the Moon? NASA’s working on it – TechCrunch



If you’re driving your car from Portland to Merced, you probably rely on GPS to see where you are. But what if you’re driving your Moon rover from Oceanus Procellarum to the Sea of Tranquility? Actually, GPS should be fine — if this NASA research pans out.

Knowing exactly where you are in space, relative to other bodies anyway, is definitely a non-trivial problem. Fortunately the stars are fixed and by triangulating with them and other known landmarks, a spacecraft can figure out its location quite precisely.

But that’s so much work! Here on Earth we gave that up years ago, and now rely (perhaps too much) on GPS to tell us where we are within a few meters.

By creating our own fixed stars — satellites in geosynchronous orbits — constantly emitting known signals, we made it possible for our devices to quickly sample those signals and immediately locate themselves.

That sure would be handy on the Moon, but a quarter of a million miles makes a lot of difference to a system that relies on ultra-precise timing and signal measurement. Yet there’s nothing theoretically barring GPS signals from being measured out there — and in fact, NASA has already done it at nearly half that distance with the MMS mission a few years ago.

“NASA has been pushing high-altitude GPS technology for years,” said MMS system architect Luke Winternitz in a NASA news release. “GPS around the Moon is the next frontier.”

Astronauts can’t just take their phones up there, of course. Our devices are calibrated for catching and calculating signals from satellites known to be in orbit above us and within a certain range of distances. The time for the signal to reach us from orbit is a fraction of a second, while on or near the Moon it would take perhaps a full second and a half. That may not sound like much, but it fundamentally affects how the receiving and processing systems have to be built.

navcube 0That’s precisely what the team at NASA Goddard has been working on addressing with a new navigation computer that uses a special high-gain antenna, a super-precise clock and other improvements over the earlier NavCube space GPS system and, of course, the terrestrial ones we all have in our phones.

The idea is to use GPS instead of relying on NASA’s network of ground and satellite measurement systems, which must exchange data to the spacecraft and eat up valuable bandwidth and power. Freeing up those systems could empower them to work on other missions and let more of the GPS-capable satellite’s communications be dedicated to science and other high-priority transmissions.

The team hopes to complete the lunar NavCube hardware by the end of the year and then find a flight to the Moon on which to test it as soon as possible. Fortunately, with Artemis gaining traction, it looks as if there will be no shortage of those.

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Chairs Technica: We review two new models from Anda Seat



Last October, we reviewed a pair of gaming / home office chairs—Secretlab’s Omega and Anda Seat’s more explicitly gaming-themed Fnatic. After several weeks of daily use, the Anda Fnatic took the crown for “favorite chair in the Salter household”—so when Anda offered two more models for review, we snapped them up.

Those two models are the Kaiser 2 and T-Pro 2, neither of which has an explicit esports team affiliation like the Anda Fnatic’s. This means a more austere appearance—particularly in the case of the T-Pro 2, which doesn’t share the Fnatic and Kaiser 2’s neck-height “wings.” Much like the Fnatic, these are excellent chairs—but having all three on hand at once made it clear how important picking the right chair for you and your body really is.

Unboxing and assembly

Assembling the Fnatic, Kaiser 2, and T-Pro 2 chairs all follows the same, simple blueprint:

  • Stuff the wheels into the five-lobed star base
  • Drop the piston into the star base
  • Drop the piston dust cap onto the piston
  • Bolt the arms to the seat
  • Bolt the seat back to the seat
  • Bolt the soft plastic dust cover over the exposed seat back bolts
  • Bolt the height adjuster to the bottom of the seat base
  • Drop the assembled seat onto the piston in the base
  • c h a i r

This is a simple process, and none of it is physically demanding; I completed it without a helper in 10 minutes or less, including picture-taking, for each of the three Anda models I assembled. The included hex key is a sufficient tool for the job—although it’s a little annoying that each end is a different size, due to the different heads on the dust cover bolts versus the rest of them. If you’ve got your own set of hex keys / Allen wrenches, you may prefer to use it for the bolts on the seat back to avoid nudging the seat arms.

If Anda has more than one version of their assembly manual, I haven’t seen it—despite looking nothing like the Kaiser 2 or Fnatic, the T-Pro 2 came with the same manual, showing a chair with neck-level “wings.” This doesn’t get in the way of actually assembling the chair, but it gave me a nasty moment thinking I’d received the wrong chair!

Minor shipping issues

The Fnatic arrived intact, but both T-Pro 2 and Kaiser 2 had minor shipping related issues on arrival. One of the arms on the Kaiser 2 had torn entirely through the shipping box—happily, there was no actual damage done.

The T-Pro 2 arrived in an intact box, but it was a little more disassembled than it should have been. These chairs have a two-piece dust cover that fits over the junction between seat and back—a triangular cover that goes over the recline mechanism, and a separate bolt cover that hides the bolts connecting the back to the brackets attached to the seat. The triangular recline mechanism cap is installed at the factory and should not come off; it’s further locked into place by a tab on the bolt cover once the chair is fully assembled.

On the right side of the T-Pro 2, the recline mechanism cover was missing, which I didn’t notice until it came time to attach the bolt cover on that side. Rummaging through the box produced the missing cap, which snapped onto the mechanism after a little fumbling. By itself, the recline mechanism cover didn’t snap on very securely—it tended to pop back off easily. Adding the bolt cover—which has a tab that snaps into a recess on the recline mechanism cover—solved that issue.

Once fully assembled, I had no further issues with the T-Pro 2’s originally iffy dust cover.

Goldilocks and the Three Chairs

Anda Seat Kaiser 2 & Anda Seat T-Pro 2

(Ars Technica may earn compensation for sales from links on this post through affiliate programs.)

Although the Fnatic and Kaiser 2 share the same frame, they have significantly different upholstery—the padding and “vegan leather” covering in the Kaiser 2 is considerably firmer than that in the Fnatic. The pillows in the Kaiser 2 are the same vegan leather as the chair and share its firmness; the pillows on the Fnatic are covered in a velour-like cloth and are significantly “squooshier.”

The T-Pro 2 stands out considerably farther, with a different frame, cloth covering instead of vegan leather, and even firmer padding than the Kaiser 2. It’s not quite as firm as the Secretlab Omega in my office—but it’s close. Its pillows are soft with velour-like covering, similar to the Fnatic’s.

Opinion one—5’11”

Having all three chairs on hand at once makes very clear that size matters. At 5’11”, all three chairs fit me reasonably well—but I needed to adjust the neck pillow on the Fnatic and Kaiser 2 up an inch or two, in order to get the support where I needed it. The T-Pro 2 had the opposite problem—on it, I needed to adjust the neck pillow down by about an inch.

The T-Pro 2 required less actual adjustment to get where it needed to be for my frame, but I found myself missing the pass-through “wings” on the Kaiser 2 and Fnatic. It was much easier and more comfortable to adjust the height of a pillow whose straps were run through pass-through holes, than yanking on one just sort of slid onto the neck area of the T-Pro 2.

After spending plenty of time in all three chairs, I like the Kaiser 2 the most, followed closely by the Fnatic. Styling issues aside, I appreciate the greater firmness and all-vegan-leather covering of the Kaiser 2 over the Fnatic. The T-Pro 2 came in last place, for me—wrestling with the neck pillow felt obnoxious, and I just plain prefer spill-resistant vegan leather to cloth.

With that said, all three chairs worked well for me—I’d choose any of the three over the Secretlab Omega in my office; and I like that one better than anything which came before it.

Opinion two—5’6”

My wife joined me in trying out all three chairs. The Fnatic has been her office chair for several months now, and she’s praised it pretty thoroughly—she describes it as “too big for [her], but in a good way.” She appreciates its generous but soft covering and padding, and she occasionally sits criss-cross applesauce in it when she’s tired of the standard, upright “srs bzness” seat position.

She was initially excited about the T-Pro 2, due to its cloth covering—but she couldn’t make its much higher neck pillow position work for her, she didn’t like its extra-firm padding, and her feet didn’t sit flat on the floor, even with the height adjusted all the way down and the seat incline fully vertical. After we spent five or 10 minutes going through every ergonomic adjustment possible—she pronounced it “usable” but still not something she felt truly comfortable with.

The Kaiser 2 met with considerably more approval—which wasn’t surprising, since it shares the same chassis as the Fnatic. She still greatly preferred the Fnatic, to my surprise, and despite spending as much time on ergonomic adjustment as we had with the T-Pro 2. The Kaiser 2’s firmer padding changed her perception of the chair as “too big, but in a good way” to just plain “too big.” She also wasn’t able to comfortably sit criss-cross in the firmer chair.

Despite her strong and unhesitating preference for the Fnatic, Janis declared that it’s better than anything she’d been given in an office job, and she’d have been thrilled to get one—if she hadn’t tried the Fnatic first.

Ergonomic adjustments

All three Anda chairs feature the same overall set of adjustments:

  • Seat height adjustment (via gas piston)
  • Seat recline adjustment (angle of seat to back, via lever)
  • Seat tilt adjustment (angle of seat+back as a unit to the floor, via rocking)
  • Seat tilt lock (can be locked at any angle desired)
  • Seat arm height
  • Seat arm depth (they can be slid forward away from the body, or closer toward the body)
  • Seat arm width (adjustable by rectangular bolthole during installation)
  • Seat arm width (further adjustable by button on arms, during usage)
  • Seat arm pivot (can be rotated horizontally, e.g., to support hands resting atop one another on the desk)
  • Removable lumbar support pillow, with removable washable cover
  • Removable neck pillow, with elastic support band and removable washable cover

To achieve the ideal posture and support, you’ll likely need to fiddle with every single one of these adjustments—particularly if you spend many hours a day seated. This isn’t unique to Anda chairs; it’s true of any chair. If you don’t feel that there’s much difference between the various adjustments on a chair, the odds are good that it simply fits you so poorly that nothing works.

One thing that I appreciate about all three of these Anda models is that the removable pillows work for me. Although I generally want to adjust the position of the lumbar and neck pillows manually by an inch or so each time I sit down, it doesn’t take any real work to get them where they need to go, and they feel good once there.

By contrast, I can’t make my Secretlab Omega’s lumbar support pillow work for me, no matter what I try—or its neck pillow. I actually ended up pulling the neck pillow off the Omega and using it as a lumbar support pillow instead—which works, but it’s considerably more of a fiddly annoyance each time I sit down, since it falls down entirely instead of staying largely in place like the proper lumbar pillows do on the Anda chairs.


I’ve learned several things in the last six months’ gaming-chair experimentation. One is that gaming chairs are not “just a meme”—while I’ve never personally owned an Aeron or Steelcase chair, I’ve been supplied with Aerons in office jobs, and failed to be impressed. There are certainly crappy gaming chairs, just as there are crappy office chairs—but the good ones are quite good, and they’re significantly less expensive.

Another is that size matters. As a 5’11” dude at 200 pounds and change, this was an easy distinction to miss—pretty much everything out there is designed for people sized and shaped reasonably like me. My wife—who, at 5’6″, is slightly taller than average for American women—had a much less forgiving experience finding the right chair for her, whether in office or gaming chairs.

Knowing all this, I think the biggest advantage that “proper” office chairs have is the ability to go sit in one in a showroom and find one that actually fits your frame properly. The difference between a chair that accommodates you properly and one that doesn’t is enormous. If you’re shorter than 5’8″, this goes double—and I strongly recommend that you at least seek out specific reviews from other folks your size, if you can’t seek out demo chairs to physically test for yourself.

If you’re 5’8″ or under, the Anda T-Pro 2 is not going to be for you—particularly not if you want the neck pillow installed. If you’re 5’8″ or taller, either the Kaiser 2 or Fnatic will likely be a good fit—though I’m not sure how well either would work for folks much taller than 6’1″. If you’re 6’2″ or taller, I’d recommend skipping the Kaiser and Fnatic, and taking a look at the T-Pro 2.

One final, cautionary word about height: just checking the backrest height on a chair won’t tell you what you need to know. The Fnatic, Kaiser 2, T-Pro all share a backrest height of 34.2″—not much different from Secretlab Titan XL 2020’s backrest height of 33.5″. But the curvature of the backrest—and the position of the neck pillow, if installed—makes an enormous difference.

Listing image by Jim Salter

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Apple clarifies iOS default music app feature, and it’s not what people thought



Enlarge / Siri in iOS 14.

Samuel Axon

Over the past several weeks, there have been several reports (including one of our own) on a feature found in recent beta releases of iOS 14.5 that appeared to allow users to change the default music app on their iPhones. However, Apple just clarified to TechCrunch that the feature is not as it first seemed.

In the initial reports, users claimed that they were prompted to select a preferred music app, such as Spotify or Apple Music, when they asked Siri to play a song. They then found that Siri seemed to honor that choice on future requests.

Further, they noticed that using the usual command “Hey Siri, play [song name] on Spotify” would cause Siri to use Spotify again in the future when they spoke the same request sans the “on Spotify” part. (In the current public version of iOS, users must say “on Spotify” every single time to play songs in that app instead of Apple Music.)

But Apple told TechCrunch that this behavior is not actually setting the default player and that it will not do so when iOS 14.5 releases to the public in the coming weeks, either. Rather, this behavior is a question Siri may periodically ask in order to intelligently pick apps on your behalf based on the nature of the content you’re asking for.

Among other things, this means that Siri might serve you a different app when you ask for a podcast than it might when you request a pop song. But in any case, it’s not a default app selection, per se, and Siri could decide to pick an app based on any number of factors beyond that. Siri may also ask you which app to use again periodically to further clarify or refine its choices.

Users of the beta did experience Siri asking a second or third time, but most interpreted that as a bug that caused the software to forget a default setting rather than an intended behavior.

Apple also told TechCrunch that there will be no place in the Settings app to set a default music player, as there is for email or browser apps since iOS 14 launched late last year.

That change in policy and functionality regarding email and browser apps was a surprise from Apple, as the company has long insisted that its own apps be the defaults on its mobile operating system, much to the frustration of users who wanted more control. It is unclear whether Apple made the change to provide a better user experience, to undermine current and future antitrust accusations and investigations, or a little of both.

But if the goal was to battle antitrust arguments, any continual preferential treatment for Apple Music is prickly. While antitrust investigations into the company have to do with more than just music apps, one of the most threatening investigations is the one in the EU instigated by Spotify, which claims that Apple unfairly gives preference to Apple Music in numerous parts of the iOS user experience.

That said, the new way Siri is said by Apple to handle music streaming services may actually be service-agnostic in terms of how it will pick services to respond to user requests based on past user behavior. But as is the case with many of these AI assistant features, it’s not likely to be all that clear to users exactly how Siri will make its judgments.

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The Realme GT 5G is the world’s cheapest Snapdragon 888 phone



It’s time for a yearly reminder of how much better the smartphone market is when you live in a hyper-competitive area like India or China. The new Realme GT 5G is now the world’s cheapest Snapdragon 888 smartphone, sporting nearly everything you would expect from a ~$1,000 flagship smartphone, for the low price of CNY 2,799, or ~$433. Naturally, the phone is for sale only in China right now.

The specs here look fantastic for the price: a 120 Hz, 6.43-inch, 2400×1080 Samsung OLED panel; a Snapdragon 88 SoC; 8GB of RAM; 128GB of UFS; a 4500 mAh battery; 65 W wired fast charging; an under-screen fingerprint reader; NFC; a USB-C slot; and a headphone jack. There’s also a higher-tier version with 12GB of RAM and 256GB of storage for CNY 3,299, or ~$510. The OS is Android 11 with a “Realme UI 2.0” skin. If you really want to pick nits, there are some cut corners here, like the lack of wireless charging and water resistance. For $430, though, this is a spectacular package.

Realme is playing some games with the pricing. The $430 and $510 price tags are “first sale” prices. At some point in the future, they will go up to CNY 2,899 (~$448) and CNY 3,399 (~$525). That still makes this the cheapest Snapdragon 888 phone on the market, but slightly less cheap.

The cameras aren’t in the flagship tier; the phone sports a mid-range 64 MP Sony IMX682 as the main camera, an 8 MP ultrawide, and a just-for-looks 2 MP “macro” camera. But Realme actually has an interesting take on phone cameras. The company says it is taking a “dual flagship strategy” with a “performance flagship” (this phone) and a “camera flagship” (some other, unannounced phone). I fully endorse the idea of a phone for people who don’t care about tiny phone cameras, but the company should commit to the idea and only have one rear camera for basic stuff and use the space it saves for a bigger battery. This supposedly non-camera-focused phone still has three rear cameras (a ridiculous amount of cameras!), and one of them is a barely functional 2 MP junker.

We’re getting some design flair with the GT 5G, too. The yellow version has a faux-leather back, and the dark and light blue versions are glass.

Realme is a sub-brand of the Chinese smartphone giant BBK, the same company that owns Oppo, OnePlus, Vivo, and iQoo. Realme mainly does business in India and China, though it has started to creep into the European market. For now, this phone is only in China, but any of Realme’s usual stomping grounds have a chance at getting it in the future. The phone ships March 10.

Listing image by Realme

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