Original image
Warner Bros.

10 Things to Know About Gravity

Original image
Warner Bros.

Director Alfonso Cua­rón’s latest film, Gravity, hits theaters today. The sci-fi flick is receiving rave reviews from critics and other filmmakers alike. Here are a few things you should know about the production. Warning: Spoilers below!

1. Its premise isn’t far-fetched.

Russia’s planned destruction of one of its own satellites kicks off the events in Gravity. Debris from that event destroys Dr. Ryan Stone (Sandra Bullock) and astronaut Matt Kowalski (George Clooney)’s shuttle and strands them in space. It might seem like no nation would ever do this, but, in fact, it’s actually happened: In 2007, China took out one of its own defunct weather satellites, sending a cloud of shrapnel “hurtling at nearly 16,000 mph along the main thoroughfare used by orbiting spacecraft,” according to Popular Mechanics. That debris joined the veritable garbage dump already orbiting above Earth, which consists of everything from rocket boosters to paint chips.

“On all of my missions, [we got] some warning from Mission Control about possible conjunctions—possible close approach by orbital debris,” former astronaut Tom Jones said at a special Popular Mechanics screening of Gravity. “You can see on radar everything that’s bigger than your fist. NORAD tracks it, and if you have to, you can maneuver the shuttle—even the [International Space Station (ISS)] has some small thrusters where it can nudge itself out of a critical path. So far we haven’t had any big impacts on human vehicles, but we’ve lost a couple of satellites from space debris.” Even small debris, traveling at those speeds, harms space infrastructure. Jones said the 2007 Chinese ASAT test doubled the debris risk to astronauts on the ISS. (Debris in space does eventually succumb to Earth’s orbit and burn up in the atmosphere, but depending on the size of the object and its orbital height, that process can take decades.)

The dangerous chain reaction of destruction seen in Gravity has a name: Kessler Syndrome, when there’s so much debris in space that everything crashes into everything else, creating more debris and therefore more collisions, rending space exploration too dangerous. It was a direct inspiration for Cua­rón and his son, Jonas, when they were writing the film.

2. It took 4.5 years to make…

Warner Bros.

Often, the only real things in a shot are Clooney's and Bullock’s faces. Everything else, from their space suits to Mother Earth, is computer generated. So Cua­rón and company created the entire film as animation first, working with sound effects, music, and lighting. “Then all that animation translated to actual camera moves and positions for the lighting and actors,” Cua­rón told Wired. “We did a whole exploration of the screenplay, every single moment; we made judgments about everything. Once we began shooting, we were constrained by the limitations of that programming.” The animation process lasted almost 2.5 years before they even began shooting with the actors.

3. ...and they had to invent new technology to do it.

“You want to pretend this is going to be easy,” Cua­rón told TheWrap. “Then it’s months and months of trying to figure out how. You come to the theory, and then you have to apply the theory, meaning to develop the technology.”

Among the new technology created for the film was a 12-wire rig devised by Special Effects supervisor Neil Corbould and his team that was controlled by puppeteers (from the play War Horse) to give the illusion that Bullock was floating through space; specialized rigs that could rotate or lift the actors at many different angles; and huge, computer-controlled robot arms typically used for car manufacturing that instead wielded cameras.

But the piece de resistance was what the filmmakers call the Light Box, a hollow cube with interior walls fitted with LEDs. The brainchild of Director of Photography Emmanuel Lubezki—who got the idea from LED lighting effects and projects at a concert—and visual effects supervisor Tim Webber, the Light Box was necessary because animators had to match up the lighting in the animation with the live action shoot perfectly. Cua­rón told ComingSoon that the finished box was raised on a six-foot-high platform and was 9 feet by 9 feet on the inside. It was fitted with 4096 LED bulbs that could show any CG image—the Earth, the sun, the stars—to get the correct lighting. According to The Wrap, about 60 percent of Gravity was shot in the box.

All of the technology could be synced with computers so that the filmmakers could move the universe around the actors.

4. Rejected strategies for filming "microgravity" included using wires and flying in the vomit comet.

Typically, wires have been used to suspend actors and give the illusion of floating, and Apollo 13 famously built sets and filmed inside a parabolic plane, which plummets for 25 seconds to create Zero Gravity. But though they were both considered, ultimately the filmmakers determined that neither would work because of Cuarón’s love of long takes (Gravity opens with a single, 15 minute shot). Bullock, who had signed on when the Zero G plane was still the plan, was relieved when it was scrapped. “I’m petrified of flying,” she told Vogue. “Plummeting out of the sky was not my idea of how I wanted to work with Alfonso Cua­rón. But at one point I sat down and said, ‘What is it about this movie that is telling me to get off my ass and get over something that has paralyzed me?’” Cua­rón said the system they eventually came up with was painful for Bullock, “but after not having to do the Vomit Comet, she was so happy, she didn’t care.”

5. Bullock trained to mimic movement in microgravity.

Her background as a dancer certainly helped Bullock pull off Gravity’s most difficult trick: Making it appear as though she was in microgravity. She worked with a pair of Australian dancers to retrain her body “from the neck down, to react and move as though it’s in Zero G, without the benefit of Zero G moving your body,” she told Collider. “Because everything that your body reacts to, with a push or a pull, and on the ground, is completely different than it is in Zero G.”

6. And she got advice straight from the ISS.

Bullock told Collider that Dr. Cady Coleman called her from the ISS to impart some advice. “I was able to literally ask someone who’s experiencing the things that I was trying to physically learn about how the body works, and what you do, and what I need to re-teach my body to do, physically, that cannot happen on earth,” Bullock said. “It’s just the oddest thing to reprogram your reactions. It was just a really coincidental, fortuitous thing that happened, over wine, that got me the final piece of the information that I needed.”

7. Cua­rón consulted with advisors, too.

The director very much wanted to make a film that was based in reality, with technology astronauts use today. (Even though the shuttle program has been discontinued, he made a decision to include it as a touchpoint for the audience.) He told ComingSoon that after he and Jonas wrote the first draft of the screenplay, they began involving experts because “we realized all the stupid things that we have described that would be completely implausible. Then, throughout the process, we kept on having advisors, not only NASA and astronauts and other people that are experts in different fields, but also physicists, trying to explain to us how objects react in micro-gravity and zero resistance. That was probably the toughest innovation, because what happens in micro-gravity and zero resistance is completely counter-intuitive.”

8. While taking liberties, the filmmakers tried to be pretty true to reality.

“We went through pains to make sure that the behavior of objects in micro-gravity and no resistance was as accurate as possible,” Cua­rón told the Huffington Post. At this same time, “this is not a documentary. We took certain liberties. Part of the liberties we took were in the sense of we would stretch the possibilities of certain things.”

There’s no sound in space, so Cua­rón mostly stuck to silence (there is a score, though). “The only sound you hear in space in the film is if, say, one of the characters is using a drill,” he told Wired. “Sandra’s character would hear the drill through the vibrations through her hand. But vibration itself doesn’t transmit in space—you can only hear what our characters are interacting with. I thought about keeping everything in absolute silence.” Another big no-no: Fires. “There’s no fire in space. At one point there’s an explosion, and the only fire you see is the bit that was inside the shuttle and then extinguished.”

9. Astronauts have given Gravity their seals of approval.

In the Hollywood Reporter, moon walker Buzz Aldrin wrote that “I was so extravagantly impressed by the portrayal of the reality of zero gravity. I was happy to see someone moving around the spacecraft the way George Clooney was. It really points out the degree of confusion and bumping into people, and when the tether gets caught, you're going to be pulled—I think the simulation of the dynamics was remarkable.”

At the Popular Mechanics screening, Jones called Gravity “probably the most realistic space film that I’ve seen,” pointing out that, in particular, the tethers outside the spacecraft in the film behaved as they do in real life. Jones told mental_floss that “When she’s moving inside the spacecraft, and she’s seeing things drifting around her, the helmet floating around, all of that was really realistic. That’s what was the most evocative of my experience.” Jones even watched a part of the ISS he helped build be destroyed, and said that the inside of the station was just as he remembered.

Not that the filmmakers got everything right: Aldrin notes that he and his crew weren't as carefree as Clooney's character, and Jones said that "in that initial collision, they’re bouncing around so much, your suit can’t withstand that—it would rupture," Jones said. "The movie would be very short! That's where they took some [creative] license." They also took a little license with the location of the orbiting spacecraft, placing the Hubble Space Telescope, the ISS, and the Chinese space lab Tiangong 1 all in the same orbit, when in fact, they're all in different orbits. In an interview with, the director said that "we did a draft where we tried to respect everything. Everything was just about explaining to the audiences all of that stuff, so we had to try to create a balance."

10. Even James Cameron loved it!

“I was stunned, absolutely floored,” the director and innovator told Variety. “I think it’s the best space photography ever done, I think it’s the best space film ever done, and it’s the movie I've been hungry to see for an awful long time.”

Original image
iStock // Ekaterina Minaeva
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
Original image
iStock // Ekaterina Minaeva

Jacques Mattheij made a small, but awesome, mistake. He went on eBay one evening and bid on a bunch of bulk LEGO brick auctions, then went to sleep. Upon waking, he discovered that he was the high bidder on many, and was now the proud owner of two tons of LEGO bricks. (This is about 4400 pounds.) He wrote, "[L]esson 1: if you win almost all bids you are bidding too high."

Mattheij had noticed that bulk, unsorted bricks sell for something like €10/kilogram, whereas sets are roughly €40/kg and rare parts go for up to €100/kg. Much of the value of the bricks is in their sorting. If he could reduce the entropy of these bins of unsorted bricks, he could make a tidy profit. While many people do this work by hand, the problem is enormous—just the kind of challenge for a computer. Mattheij writes:

There are 38000+ shapes and there are 100+ possible shades of color (you can roughly tell how old someone is by asking them what lego colors they remember from their youth).

In the following months, Mattheij built a proof-of-concept sorting system using, of course, LEGO. He broke the problem down into a series of sub-problems (including "feeding LEGO reliably from a hopper is surprisingly hard," one of those facts of nature that will stymie even the best system design). After tinkering with the prototype at length, he expanded the system to a surprisingly complex system of conveyer belts (powered by a home treadmill), various pieces of cabinetry, and "copious quantities of crazy glue."

Here's a video showing the current system running at low speed:

The key part of the system was running the bricks past a camera paired with a computer running a neural net-based image classifier. That allows the computer (when sufficiently trained on brick images) to recognize bricks and thus categorize them by color, shape, or other parameters. Remember that as bricks pass by, they can be in any orientation, can be dirty, can even be stuck to other pieces. So having a flexible software system is key to recognizing—in a fraction of a second—what a given brick is, in order to sort it out. When a match is found, a jet of compressed air pops the piece off the conveyer belt and into a waiting bin.

After much experimentation, Mattheij rewrote the software (several times in fact) to accomplish a variety of basic tasks. At its core, the system takes images from a webcam and feeds them to a neural network to do the classification. Of course, the neural net needs to be "trained" by showing it lots of images, and telling it what those images represent. Mattheij's breakthrough was allowing the machine to effectively train itself, with guidance: Running pieces through allows the system to take its own photos, make a guess, and build on that guess. As long as Mattheij corrects the incorrect guesses, he ends up with a decent (and self-reinforcing) corpus of training data. As the machine continues running, it can rack up more training, allowing it to recognize a broad variety of pieces on the fly.

Here's another video, focusing on how the pieces move on conveyer belts (running at slow speed so puny humans can follow). You can also see the air jets in action:

In an email interview, Mattheij told Mental Floss that the system currently sorts LEGO bricks into more than 50 categories. It can also be run in a color-sorting mode to bin the parts across 12 color groups. (Thus at present you'd likely do a two-pass sort on the bricks: once for shape, then a separate pass for color.) He continues to refine the system, with a focus on making its recognition abilities faster. At some point down the line, he plans to make the software portion open source. You're on your own as far as building conveyer belts, bins, and so forth.

Check out Mattheij's writeup in two parts for more information. It starts with an overview of the story, followed up with a deep dive on the software. He's also tweeting about the project (among other things). And if you look around a bit, you'll find bulk LEGO brick auctions online—it's definitely a thing!

Original image
Here's How to Change Your Name on Facebook
Original image

Whether you want to change your legal name, adopt a new nickname, or simply reinvent your online persona, it's helpful to know the process of resetting your name on Facebook. The social media site isn't a fan of fake accounts, and as a result changing your name is a little more complicated than updating your profile picture or relationship status. Luckily, Daily Dot laid out the steps.

Start by going to the blue bar at the top of the page in desktop view and clicking the down arrow to the far right. From here, go to Settings. This should take you to the General Account Settings page. Find your name as it appears on your profile and click the Edit link to the right of it. Now, you can input your preferred first and last name, and if you’d like, your middle name.

The steps are similar in Facebook mobile. To find Settings, tap the More option in the bottom right corner. Go to Account Settings, then General, then hit your name to change it.

Whatever you type should adhere to Facebook's guidelines, which prohibit symbols, numbers, unusual capitalization, and honorifics like Mr., Ms., and Dr. Before landing on a name, make sure you’re ready to commit to it: Facebook won’t let you update it again for 60 days. If you aren’t happy with these restrictions, adding a secondary name or a name pronunciation might better suit your needs. You can do this by going to the Details About You heading under the About page of your profile.

[h/t Daily Dot]