Science and Technology Thread

Postby **tifosi77** » Wed May 27, 2015 1:18 pm

Elon’s SpaceX Gets Certified For National Security Launches; Can You Say Disruption?

While few doubted it would happen, the news that Elon Musk’s scrappy, pushy and — yes — disruptive launch company SpaceX won certification from Space and Missile Systems Center carries enormous import for the international launch industry, for the Pentagon, the Air Force and the Intelligence Community.

It’s not that Musk’s SpaceX is going to win deals tomorrow from the current national security launch monopoly, the United Launch Alliance. It’s that Musk has proven to many of the world’s most demanding acquisition experts and systems engineers that a commercial company can do rocket science to the same standards as ULA’s Boeing and Lockheed Martin.

Postby **columbia** » Wed May 27, 2015 1:25 pm

That's cool, though I'm more interested in his plans for batteries.

Postby **Shyster** » Wed May 27, 2015 6:14 pm

http://breakingdefense.com/2015/05/elon ... disruption

A rather backhanded article, if you ask me. It mentions the failures of the Falcon 1 as if they were recent, but doesn't mention that every Falcon 9 flight has succeeded in its primary mission, including every mission of the 1.1 version. It also claims that Elon Musk "just didn’t understand that they took this really seriously and didn’t care if he wanted it to happen faster." Uh, no. While SpaceX was somewhat to blame in the certification delay and was naïve on what that process would take, the Air Force approached the certification process as if it were a "design review" that would entitle them to order SpaceX to make whatever changes to their equipment, systems, personnel, etc. that the Air Force wanted. Essentially, the AF wanted to turn SpaceX into another ULA, which is so entrenched in government work that it could practically be considered a government agency. The rancor got so bad between SpaceX and the AF that an Independent Review Committee stepped in to handle the matter, and you can read its report here:

https://drive.google.com/file/d/0B7lrYp ... VRT2s/view

While blame is placed on SpaceX, I think the report rebukes the government more. For example, this is one of the recommendations:

Clearly establish that the expectation is that the Air Force, NRO, and NASA will benefit from buying services from SpaceX as a commercial provider and that attempting to drive SpaceX to a different model is counterproductive to the reason for the national policy on encouraging the use of qualified commercial providers for national security payloads.

Postby **tifosi77** » Thu May 28, 2015 12:14 pm

Yeah, I definitely got the same vibe from the article. It's from a site that I've only recently started following, so the editorial tone is still somewhat of a hit-and-miss thing for me.

Postby **Sam's Drunk Dog** » Sun May 31, 2015 8:03 pm

Longest Floating Structure In History Sets Out To Clean The Ocean In 2016

Read More: http://www.trueactivist.com/longest-flo ... n-in-2016/

Postby **count2infinity** » Sun May 31, 2015 8:10 pm

http://www.seattletimes.com/nation-worl ... h-science/

Pope Francis, once a chemist, will soon issue an authoritative church document laying out the moral justification for fighting global warming, especially for the world's poorest billions.

Postby **columbia** » Mon Jun 01, 2015 6:57 am

Carnegie Mellon Reels After Uber Lures Away Researchers
http://www.wsj.com/articles/is-uber-a-f ... 1433084582

Postby **Gaucho** » Mon Jun 01, 2015 7:45 am

Longest Floating Structure In History Sets Out To Clean The Ocean In 2016

Read More: http://www.trueactivist.com/longest-flo ... n-in-2016/

A 19-year-old. Go figure.

Postby **redwill** » Sat Jun 06, 2015 9:03 pm

Similar to my last post about steam coming off a pot of heated water, I've been wondering for a long time about wearing white vs. black on a hot, sunny day.

I read Jurassic Park about twenty years ago, and a character mentioned "black-body radiation":

But no, as a matter of fact, black is an excellent color for heat. If you remember your black-body radiation, black is actually best in heat. Efficient radiation.

To Google!

Much debate, but there's this:

http://io9.com/5903956/the-physics-that ... his-summer

But, jeez, wearing white in the hot summer sun is cooler, right? I think we can all attest to that. Or ... maybe not.

Postby **tifosi77** » Mon Jun 08, 2015 6:03 pm

To that point, I never understood why the Miami Dolphins wear their white unis at home.

Postby **columbia** » Fri Jun 12, 2015 9:03 am

Postby **obhave** » Fri Jun 12, 2015 9:54 am

Hah!

The "distractingly sexy" tweets have been pretty great the past few days.

Postby **count2infinity** » Fri Jun 12, 2015 10:20 am

I hadn't read the article before I saw a friend of mine (grad student at Michigan) post this on facebook:

Taking a break from all of my crying in the lab and distracting my male coworkers to post this...

I was about to send her a message and ask if everything was okay, because she got married about a year ago, grad school can certain put a strain on any relationship, let alone a marriage, she's right in the middle of prepping for her comps, just a lot of stress that I remember going through, but I read the article she posted first (thankfully... lol).

http://mashable.com/2015/06/11/female-s ... ZvcGt1aCJ9

My guess is that Tim Hunt hasn't spent much time in modern labs (won his Nobel Prize 14 years ago... I'd imagine he's largely been on lecture tours since then). It's not a good ole boys club like it probably was back when he went through grad school.

CSB time... tl;dnr: sexist jerk lasted about 3 months in grad school.

We had this kid in my incoming class... let's call him Richard (mostly because the dude was a dick). Upon arrival there is a lot of orientation because grad school is a way different monster than undergrad. We took placement exams, he knew every answer to every question (to put it in perspective, he passed all 5. I passed a measly zero... but that's okay, the exams don't really mean much other than giving you freedom to schedule any courses you wanted to take). He largely bragged about knowing the answers to every question. So smart kid and he knew it. The fun part came when he started training to be a TA and looking for a lab to join. At the point I had already come in early over the summer, worked in a few labs, found a home, so I was safe. Essentially in the program if you don't find a lab, you're out.

TA training: My wife (girlfriend at the time) was a supervising TA and was in charge of the training for his class. The training is pretty easy... you do all the labs the students are going to do, exactly as the students do them, so you do the notebook thing, fill out the worksheets, take quizzes, etc. It was gen chem and he thought that he was above that so he started goofing off, not doing the work, not being safe, so my wife (after numerous conversations with him) decided to have a sit down with him and the head of the gen chem classes. In this meeting he called her a "pedantic schoolmarm" and pretty much said he was above having to do this work. He was removed from that training session and placed in another. Word got out about this kid pretty quickly.

Searching for a lab: After he burned quite a few bridges in TA training the quest to find a lab to work in was.... interesting. First he sought out a lab with no females in it. Turns out not only here at PSU does pretty much every lab have a female in it, but for the most part the women outnumber the men. When that quest failed he found a lab that he was pretty interested in their research and they changed their group meeting schedule without telling him and asked him not to come back. The next lab he tried, a senior female grad student was showing him around the lab and he told her "could you find a male lab member to do this? I learn much better from men..." Needless to say this didn't go over well. Finally he had exhausted all the labs in the department and ended up leaving.

Right around the time between TA training and searching for a lab, we found out that he was homeschooled up to high school where he was then sent to attend an all boys boarding school, and from there he went to Hampden-Sydney College in Virginia (all boys college) and then ended up here at PSU. He had numerous conversations with people about how single sex education is absolutely the best way to educate youth and that he felt it should still be done today.

Postby **robbiestoupe** » Fri Jun 12, 2015 10:58 am

Similar to my last post about steam coming off a pot of heated water, I've been wondering for a long time about wearing white vs. black on a hot, sunny day.

I read Jurassic Park about twenty years ago, and a character mentioned "black-body radiation":

But no, as a matter of fact, black is an excellent color for heat. If you remember your black-body radiation, black is actually best in heat. Efficient radiation.
To Google!

Much debate, but there's this:

http://io9.com/5903956/the-physics-that ... his-summer

We're all encouraged to wear white in summer, since white clothing is supposed to keep us cool — but it doesn't. In fact, black clothing is the best way to keep cool in the heat. It's basic physics. And biology. Find out why cool people will wear black this summer.

Generally in summer, we're treated to lines of loose summery white clothing. Not only is the white supposed to look nice floating around the edges of a picnic — until a few seconds into the event, when it has its first grass stain — people claim that white is the ideal way to keep cool in the summer. When we see white, we're seeing the combination of all possible visible light. This means that white clothing reflects a great deal of wavelengths of energy coming in. This means it should reflect the sun's rays back, instead of letting them cook us. And that's perfectly correct.

Except that this explanation is also incomplete. Heat is not just coming in off of the sun. It's also coming off a person's own, sweating, warm-blooded, mammalian body, which is a lot closer than the sun is. When all that body heat hits the white clothing covering it, it gets reflected right back towards the body. When we wear white, we cook ourselves.

The best color to keep cool in the heat, it turns out, is to wear black. Black absorbs everything coming in from the sun, sure. But black also absorbs energy from the body instead of reflecting it back. Now, the helpfulness of black clothes depends on finding black clothes that are the same thickness and looseness as those summery white clothes. Black clothing also needs a little help from atmospheric conditions. Once it has absorbed heat, it has to have some way to radiate it away. If there's even a little wind, black clothing is the better choice for those who want to keep cool, like goths who understandably don't like sweating through their make-up. So find something black to wear this summer.
But, jeez, wearing white in the hot summer sun is cooler, right? I think we can all attest to that. Or ... maybe not.

OK I get that our bodies give off heat and therefore an absorbent material is better than a reflective material. But you have to think about the total absorption of that material and the amount of air flow required to remove the heat from the heat sink. I'd be pretty safe to assume that the amount of radiant heat given off by the sun >> the amount of radiant heat given off by the human body. Therefore I would rather reflect that heat than absorb it.

Now, if somebody starts designing t-shirts with a black interior and white exterior, they may be on to something!

Similar side story, a friend of mine has been working on a patent for heating homes that deals with reflective technology and human body heat. Pretty interesting stuff, but I don't think it will fly mostly due to the aesthetic nature of the material. Great idea though.

Postby **shmenguin** » Fri Jun 12, 2015 11:08 am

The "distractingly sexy" tweets have been pretty great the past few days.

i side with team lady doctor here, but technically it's been one tweet repeated over and over.

Postby **columbia** » Fri Jun 12, 2015 11:10 am

Can we get a shot of you in a Speedo at the lab, c2i?
#distractinglysexy

Postby **tifosi77** » Fri Jun 12, 2015 1:08 pm

Can we get a shot of you in a Speedo at the lab, c2i?
#distractinglysexy

Spoiler tag

#thinkofthechildren

Postby **count2infinity** » Sat Jun 13, 2015 8:17 am

Similar to my last post about steam coming off a pot of heated water, I've been wondering for a long time about wearing white vs. black on a hot, sunny day.

I read Jurassic Park about twenty years ago, and a character mentioned "black-body radiation":

But no, as a matter of fact, black is an excellent color for heat. If you remember your black-body radiation, black is actually best in heat. Efficient radiation.
To Google!

Much debate, but there's this:

http://io9.com/5903956/the-physics-that ... his-summer

We're all encouraged to wear white in summer, since white clothing is supposed to keep us cool — but it doesn't. In fact, black clothing is the best way to keep cool in the heat. It's basic physics. And biology. Find out why cool people will wear black this summer.

Generally in summer, we're treated to lines of loose summery white clothing. Not only is the white supposed to look nice floating around the edges of a picnic — until a few seconds into the event, when it has its first grass stain — people claim that white is the ideal way to keep cool in the summer. When we see white, we're seeing the combination of all possible visible light. This means that white clothing reflects a great deal of wavelengths of energy coming in. This means it should reflect the sun's rays back, instead of letting them cook us. And that's perfectly correct.

Except that this explanation is also incomplete. Heat is not just coming in off of the sun. It's also coming off a person's own, sweating, warm-blooded, mammalian body, which is a lot closer than the sun is. When all that body heat hits the white clothing covering it, it gets reflected right back towards the body. When we wear white, we cook ourselves.

The best color to keep cool in the heat, it turns out, is to wear black. Black absorbs everything coming in from the sun, sure. But black also absorbs energy from the body instead of reflecting it back. Now, the helpfulness of black clothes depends on finding black clothes that are the same thickness and looseness as those summery white clothes. Black clothing also needs a little help from atmospheric conditions. Once it has absorbed heat, it has to have some way to radiate it away. If there's even a little wind, black clothing is the better choice for those who want to keep cool, like goths who understandably don't like sweating through their make-up. So find something black to wear this summer.
But, jeez, wearing white in the hot summer sun is cooler, right? I think we can all attest to that. Or ... maybe not.

I think that the person who wrote that didn't take into consideration that the body and sun provide heat via different mechanisms. The thing that causes a black shirt to heat up fast via the sun is visible (and likely some near IR) light gets absorbed by the shirt causing a change from light to heat as it absorbs. The body gives off thermal energy... yes, the body gives off IR radiation as well, but when the shirt is in direct contact or near proximity with the body, it's mostly just conduction or convection heating, not light to heat. The amount of heat that is absorbed in this manner is material dependent, not color dependent. Think about it this way, take two identical pots and put them on identical burners with identical amounts of water in them, then add 5 drops of black food coloring to one and 5 drops of white food coloring (is that a thing?) to the other and see which boils first. They're going to boil at or around the same time. So wear something light weight and white so that body heat can escape and the sun won't cook you. In other words: do what we already know works.

Postby **count2infinity** » Mon Jun 15, 2015 10:08 am

Interesting... Hunt (and his wife) say his words were merely a joke. An ill-timed, not very funny joke, but still a joke:

http://www.theguardian.com/science/2015 ... ry-collins

“I was very nervous and a bit confused but, yes, I made those remarks – which were inexcusable – but I made them in a totally jocular, ironic way. There was some polite applause and that was it, I thought. I thought everything was OK. No one accused me of being a sexist pig.”

His wife:

“It was an unbelievably stupid thing to say,” she says. “You can see why it could be taken as offensive if you didn’t know Tim. But really it was just part of his upbringing. He went to a single-sex school in the 1960s. Nevertheless he is not sexist. I am a feminist, and I would not have put up with him if he were sexist.”

Postby **shmenguin** » Mon Jun 15, 2015 10:15 am

seemed like bad comedy the whole time. even if that was the case, it was still uncool. but people took it way too literally.

Postby **Shyster** » Mon Jun 22, 2015 4:49 pm

The bright spots on Ceres are coming into better focus:
http://www.space.com/29725-ceres-bright ... -dawn.html
…although scientists still are quite sure what they are.

Postby **Shyster** » Fri Jun 26, 2015 8:23 pm

SpaceX breaks down its rocket landing attempts so far:
http://www.spacex.com/news/2015/06/24/w ... ng-rockets?

There's also a new video of the second landing attempt. The investigation of attempt #2 places blame for the hard landing on a sticky throttle valve. SpaceX says they've made changes to prevent that sticking, and the next attempt for landing is scheduled for this Sunday, which is when SpaceX plans to launch their seventh Commercial Resupply mission to the ISS. The landing will be targeting a brand-new Autonomous Spaceport Drone Ship. This one is named Of Course I Still Love You.

Postby **Shyster** » Sun Jun 28, 2015 7:32 pm

Whoops. The SpaceX CRS-7 resupply mission Did Not Go To Space Today. Shortly before staging, it looks like there was a structural failure on the liquid-oxygen tank for the upper stage. The white cloud is liquid oxygen rapidly turning back into a gas. The failure resulted in a loss of vehicle and loss of mission. This is the first total failure of any version of the Falcon 9. A tweet by Elon Musk mentioned "overpressure" in the second-stage LoX tank (pretty obvious, since it seems to have popped), but the cause is still uncertain. The same tweet from Musk says "Data suggests counterintuitive cause."

This does put the ISS in a bit of a pickle. The last two resupply missions to the ISS (this one and Progress M-27M) both failed, and while the station still has over a month's worth of supplies, they absolutely can't afford any more mishaps in the supply chain. Fortunately, another Progress resupply mission is launching next weekend. NASA said today that they're working with their Russian counterparts to see if they want to make any changes for the cargo on that mission as a result of this failure.

Postby **Shyster** » Mon Jun 29, 2015 7:55 pm

The cause of the SpaceX CRS-7 failure appears to be proving elusive (which isn't a good thing):

https://twitter.com/elonmusk/status/615431934345216001

This seems to have been a really weird failure. The failure was on the second stage, but the second stage wasn't really doing anything at the time, and this happened before staging. The first stage was still burning, and it appears to have been working just fine up to the point the FTS (flight termination system) issued a self-destruct. The failure occurred well after max-q, which is the point of maximum stress. You'd expect structural failures to happen around that time. This failure was way up in the atmosphere at a point where there's isn't much air left to push against. Failures also tend to happen in the most complex and highly stressed parts (usually the engines), but the failure is doesn't appear to have started in upper-stage engine or interstage.

Postby **tifosi77** » Mon Jun 29, 2015 7:57 pm

Is this one of those accidents that's going to end up being "someone didn't torque a bolt properly", or "a $0.20 washer failed"?