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Scott “marsroverdriver” Maxwell
Works at Google
Attended University of Illinois at Urbana-Champaign
Lives in Pasadena, CA
46,261 followers|3,815,288 views


Here are 8400 Apollo images, all scanned at 1800 DPI, free to download. Personally, I can't stop drooling.

Completely unrelated, does anyone know of a bulk Flickr downloader? I'm willing to write one myself, I just don't want to bother if there already is one.

Via +Boing Boing​.
Explore Project Apollo Archive's 8,435 photos on Flickr!
Dustin Engstrom's profile photoWilliam L. Weaver's profile photoRhesa Rozendaal's profile photoBridget Spitznagel's profile photo
These are incredible.
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Help a real space mission! The science team for NASA's Dawn spacecraft are so puzzled by certain features on the surface of Ceres that they've asked the public to suggest explanations.

But you don't get to guess that the white spot is cotton candy. I already did that one.
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Boy! That its a real mystery.
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Edit: Possibly most important, water is rocket fuel. You use electrolysis to split it back into hydrogen and oxygen, then feed that to your rocket and lift off. So round-trips to Mars become far more feasible -- you don't need to carry all of your return-trip fuel with you, you can make it in situ. Anyway, back to my original post:

For years, scientists have been puzzled by these weird dark streaks that would periodically appear (in warmer temperatures) inside some Martian craters, then disappear again when the weather turned colder. Were they caused by jets of carbon dioxide gas, or maybe some geological process we didn't understand? Now, careful work using the CRISM instrument aboard the Mars Reconnaissance Orbiter confirms that those dark streaks are periodic water flows.

Yes, liquid water. On Mars. Today.

It's not particularly life-friendly water, this -- too briny for that. It needs to be, to be liquid at the current temperature and pressure regime. But this is undeniably cool stuff all the same: it strengthens the case for past Martian water, and it adds to the growing list of places we're finding that life-giving liquid all over the solar system.

Attention, Mark Watney: you have a new resource at your disposal.
A new study provides the 'strongest evidence yet' of salty liquid water that flows on modern-day Mars, researchers said on Monday.
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He received your message :P

I was wondering, is liquid hydrogen/oxygen fuel relatively easier or more difficult to produce than perchlorate-based solid rocket propellants?
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What a surprise. I'm starting to think that it actually matters who's President. :-/
Jeb Bush just published a love note to big business that’d be amusing if it didn’t give me second-hand embarrassment at witnessing a governor slob-knob oligopolistic corporatism so explicitly.
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+Luis Avila because of the glowing recommendation about you from my brother and hero +Charles-A Rovira , I am adding you to my circle of working class heroes. I need to check out your profile in order to add you to other circles. Welcome to the group, my brother.
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So, the weird thing is, I knew this guy. I don't think I ever met him face-to-face, but he often participated in MER telecons; I knew him well enough to recognize his voice on the line. He led a mapping team at OSU that worked with rover data to help localize the rovers.

Partly because I didn't know him, I don't have particularly protective feelings about him; if he's a spy, he's a spy. But what's really interesting to me is how cynically I read this news coverage now, after having observed other cases and knowing what I know about how NASA works.

In particular, the fact that FBI agents found "restricted defense information" on his flash drives just doesn't impress me. I know for a fact that the definition of such terms is impossibly broad -- schematics of the rover body would qualify, believe it or not, and it's not like it's suspicious for a rover team member to have them -- and I also know that the FBI has every incentive to make the situation sound as important and menacing and scary as possible. So I'd want more details about those documents before I made a judgement. And that's just one example.

Here's another interpretation of the facts as we have them. Ron (everybody I knew called him "Ron") wanted to make some extra money on the side, so he worked with a Chinese university. (Note that if this association were genuinely nefarious, the university wouldn't list him publicly as a professor there -- a strike against the government's story, I think.) NASA found out about it, and he knew he'd get in serious trouble for the connection, so he fled.

Then the US government pounced on the opportunity to play up the "OMG CHINESE SPIEZ ARE EVERYWHERE" angle.

Is Ron a spy? Maybe. Is he a guy who just got a little too greedy for his own good? Maybe. Is there some other explanation? Maybe. I don't know.

All I'm sure of is that when I read such a story as this nowadays, I want to wait for a lot more facts before I believe the government's side. They've lied and exaggerated enough, quite blatantly and in recent memory, that now my natural response to them makes me feel like a conspiracy theorist. And there's not much about that that I like.
Professor Rongxing Li was a star at Ohio State University, attracting international attention as he helped NASA rovers explore Mars in the past decade. Then, early last year, Li quit his post as OSU’s premier mapping expert and disappeared. No news release was issued to explain his departure, and most information about his 18-year tenure at Ohio State was removed from the university’s website. Now, federal search warrants filed in U.S. District C...
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The Chinese are ultra duplicitous.
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Pro-GOP "think" tank asserts Ahmed’s clock was "half a bomb." OK, admittedly, without the bomb part. But otherwise, it was totally half a bomb. Totally.
Many Americans expressed outrage at the news of the Muslim high school student’s arrest for bringing a homemade clock to school. Not the Center for Security Policy .
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+Antony Jackson​ timing device, ignitor, explosive O.O YOU'RE FUCKED!!!
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I'm strongly against spoilers -- even saying whether I liked a movie or didn't -- so I won't do that here. But I did want to publicly recognize a thing this movie got exactly right: the large and unremarked-upon role of women and non-white people in a variety of positions in the space program.

The real space program is exactly like that, damn it, and it's nice to see a movie get that so right at last. The movie doesn't call attention to it, they just do it, which is exactly how it should be. (This is surely in part because the source novel does the same; it's just one of many things Weir absolutely nailed.)

It was something I really loved about that work. I drove rovers with people from Italy, from Taiwan, from Mexico, from India, from Ghana. I loved that in part because it felt like being on the bridge of The Enterprise, and also because ... well, it just felt right.

It took me a long time to realize why: it was because in a perfect world, a world in which racism and sexism played no role, that's what the team would look like. High-quality gray matter is distributed without regard to race or sex, so if you just went around the world choosing the perfect people for the work, you'd naturally end up with just that sort of diverse team.

It still wasn't perfect, but it was very very very good, a taste of how the world should be. And will be. Kudos to Ridley Scott for showing us all that world.
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+NPR has done a couple segments recently, including Andy Weir admitting that the dust storm was his one big allowance of artistic license.
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This news story has the first public hint I've seen of a feature slated for the 2020 rover: autonomous navigation in hardware. So now I can talk about it. :-)

Generally speaking, the rover drives fastest for the first part of its traverse -- up to 160m on Opportunity, but more commonly around a third of that, and even less on Curiosity -- where we chart the whole course for it. We basically say, "just close your little rover eyes and trust me on this part."

Sometimes, though, you know your direction and you just want to make as much distance as possible -- maybe there's a nifty crater a week away, and the science team says to floor it. So the rover passes the point where we could see obstacles well enough to manually plan a path around them, and from there she's on her own.

For this part of the drive, we use a feature called "autonomous navigation," or "autonav" for short: the rover takes a stereo pair of images of the world in front of it, constructs a 3-D model, and scans it for any geometric hazards (large rocks, deep ditches, and so on). If the path toward the goal looks safe, the rover moves a little bit (up to maybe 1.5m in the best case) in the desired direction, and then repeats the process.

It's slow, though: Curiosity's CPU runs at a mere 200 MHz, and Opportunity's is a tenth of that. For perspective, your desktop likely has two or four cores each at least ten times as fast as Curiosity's -- heck, your phone can run rings around it. (But then, your phone would die fast in the high-radiation Martian environment.) So it's not much horsepower to do 3-D image processing. Autonav is great as far as it goes, in that it lets you do something slowly that otherwise you couldn't do at all -- but it is slow.

Which is where the hardware acceleration comes in. Last I heard, at least, the basic plan is to fly a piece of hardware called an FPGA -- a Field-Programmable Gate Array, essentially a reprogrammable piece of hardware -- and move the autonav logic into it. This advance will do for autonav processing what graphics hardware does for gaming. The 2020 rover's wheels will still turn slowly, but at least they'll turn continuously -- and slow and steady is all it takes to win this race.
NASA's nuclear-powered Mars rover, slated to launch in 2020, will be smarter and more efficient than Curiosity, which is currently exploring Mars.
rajnesh avasthi's profile photoMario Antonio's profile photoYerraguntla Pallavi's profile photoSeby Kannampuzha's profile photo
+Robert Le Blah +Tobias Thierer​ nails it. I'd add that there's a lot of conservatism in choosing these parts: ideally, you want to use something that lots of other missions have used before, so that your CPU has been, to use the term of art, "flight-proven."
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You should read everything +Glenn Fleishman​ writes, because awesome. This, for instance.
I wrote a story for The Economist about a drone planned for the International Space Station: the Astrobee! It'll replace existing, limited drones up there now, and help give astronauts more time for more interesting work while improving safety.
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NASA's plutonium-fuel saga continues. The farther from the sun you explore, the less effective solar panels become -- far enough out, you must switch to a type of plutonium-fueled battery called an RTG (Radioisotope Thermoelectric Generator).

Now, in the good old days, Pu-238 was produced for nuclear weapons anyway, so it wasn't a big deal to just make a little more for NASA. But those days are over, and it wasn't deemed cost-effective to manufacture the stuff just for a little thing like the world's premiere space agency, so production was completely shut down. As a result, NASA's been drawing from a steadily dwindling stockpile. If they run out, many deep space missions become effectively impossible.

So it was happy news when Congress authorized the Department of Energy to resume producing Pu-238 in 2012. But now comes news that the amount of Pu-238 that DoE actually produces will be significantly less than NASA hoped for. And we won't even get that for another four years -- until 2019, the output is zero. (It takes a while to ramp up something like this -- and certainly it's not something you want to rush.)

Frustratingly, the very next year (2013), NASA was forced to essentially cancel the development of a significantly more fuel-efficient RTG, called the ASRG (Advanced Stirling RTG), for budget reasons -- it produces the same amount of power from about 25% of the plutonium. If they'd been able to keep working on the ASRG, the lower Pu-238 output wouldn't hurt as much.

So now we're in this unhappy situation: we'll get less Pu-238 per year than we thought, and we're going to need more of it than we'd expected to do the same missions.


Just to make it sting a little more, it'll cost more to produce the extra Pu-238 we now need than it would've cost to finish developing the ASRG. It was a rational cut given the way government funding works -- NASA had no choice here -- but it hurts.

There's still a skeleton crew working on the ASRG, so maybe they'll achieve some kind of miracle. If they don't, though, we're looking at a steady, possibly decades-long decline in our ability to explore beyond our own back yard.
The U.S. plans to produce new plutonium-238 for space missions in 2019, but production will ramp up slowly, and NASA may not spare any for small missions.
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I'm sure glad they're cutting back on wasting relatively tiny amounts of money on pointless things like advancing the entire human race so we have a tiny bit more to spend on important things like destroying the human race. 
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Lovely aerial tour of Pluto -- a place that was, until just a couple of months ago, essentially completely unknown to us. Bloody amazing.
Wonder what it would be like to fly over Pluto? NASA has posted a highly detailed aerial tour that gives you a taste.
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Well, now, this hits uncomfortably close to home.
Tickets for all three BAHFest shows are now available! San Francisco, MIT, and Seattle! Featuring, Kris Wilson of Cyanide and Happiness, Abby Howard of The Last Halloween, and Matt Inman of The Oatmeal! Discuss this comic in the forum. August 23, 2015. Discuss this comic in the forum ...
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It's funny because it's true. 
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In his circles
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Site Reliability Engineer
  • Google
    Site Reliability Engineer, 2013 - present
  • JPL
    Mars Rover Driver Team Lead, 2013
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Pasadena, CA
Rocky Mount, NC - Seminole, FL - Greenville, NC - Champaign, IL
I'm a pretty big wheel down at the cracker factory.
On a small red light in the night sky lives four hundred pounds of thinking metal sent from Earth.  Once upon a time, I told that metal what to do.

(Disclaimer: my opinions are mine, not my employer's.  Duh. :-)
Bragging rights
I fought cancer and won. I had a robot on another planet, and I drove it around and made it do stuff. I was a trending topic on Twitter. I wrote a book. I took a privacy case all the way to the Supreme Court. Now I keep Google up and running. But I'm just this guy, you know?
  • University of Illinois at Urbana-Champaign
    Computer Science
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@marsroverdriver on Twitter
Our AC went out over the weekend and we were *miserable*. (I used to think that when the zombocalypse comes, I'd miss showers most of all, but now I'm thinking I'll have to revise that to air conditioning.) We called In N Out Air Monday morning and were, thankfully, able to get an appointment for the same afternoon. Hovik showed up right on time, fixed our problem fast, and charged us a fair price. He was even exceptionally polite about letting me watch over his shoulder while he narrated what he was doing, so I could learn more about how AC units work! (Indeed, he was extremely professional and friendly throughout.) And boy, were we relieved when that cold air started flowing again. He emphasized on his way out that they have a one-year parts and labor guarantee. I simply could not be happier with my experience. Well done, In N Out Air!
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Roberto is one of my favorite artists. We have two of his pieces hanging in our home, soon to be joined by a third (my wedding gift to my new wife!).
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When you want this kind of food, In-N-Out does it better than anyone. And I've never had a single bad experience with an employee.
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Vroman's is my favorite bookstore of all time. Great selection, friendly and helpful staff, wonderful events, and upstairs is a terrific kids' section, greeting cards, and more. They'll even gift-wrap your purchases for free, which has been handy a number of times!
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I love this place. The staff makes me feel like part of the family, and in a part of the world crowded with Thai restaurants, Min's stands out among the best.
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