Hubble's look at the galaxy Markarian 509. Image Credit: NASA, ESA, G. Kriss (STScI), and J. de Plaa (SRON Netherlands Institute for Space Research) Acknowledgment: B. Peterson (Ohio State University) Science Credit: NASA, ESA, J. Kaastra (SRON Netherlands Institute for Space Research), and G. Kriss (STScI)

Hubble’s look at the galaxy Markarian 509.  Click for larger.  Image Credit: NASA, ESA, G. Kriss (STScI), and J. de Plaa (SRON Netherlands Institute for Space Research) Acknowledgment: B. Peterson (Ohio State University) Science Credit: NASA, ESA, J. Kaastra (SRON Netherlands Institute for Space Research), and G. Kriss (STScI)

Here’s the latest offering on Hubblesite, it’s actually a collaboration of four different observatory platforms: ESA’s XMM-Newton and INTEGRAL satellites, NASA’s Chandra X-ray Observatory and of course the Hubble Space Telescope.

For even larger versions than the one above go to Hubblesite, here’s the press release:

SEPTEMBER 29, 2011: An international team of astronomers using five different telescopes has uncovered striking features around a supermassive black hole in the core of the distant galaxy Markarian 509. They found a very hot corona hovering above the black hole and cold gas “bullets” in hotter diffuse gas, speeding outward with velocities over 1 million miles per hour. This corona absorbs and reprocesses the ultraviolet light from the accretion disk encircling the black hole, energizing it and converting it into X-rays.

This discovery allows astronomers to make sense of some of the observations of active galaxies that have been hard to explain so far. The heart of the campaign consisted of repeated visible, X-ray, and gamma-ray observations with ESA’s XMM-Newton and INTEGRAL satellites, which monitored Markarian 509 for six weeks. This was followed by long observations with NASA’s Chandra X-ray Observatory and the Hubble Space Telescope. Prior to these observations short snapshots to monitor the behavior of the source at all wavelengths were taken with NASA’s Swift satellite. The combined efforts of all these instruments gave astronomers an unprecedented insight into the core of an active galaxy.

The Cosmic Origins Spectrograph aboard Hubble reveals that the coolest gas in the line of sight toward Markarian 509 has 14 different velocity components at various locations in the innermost parts of this galaxy. Hubble’s data, combined with X-ray observations, show that most of the visible outflowing gas is blown off from a dusty gas disk surrounding the central region more than 15 light-years away from the black hole. This outflow consists of dense, cold blobs or gas bullets embedded in hotter diffuse gas. The international consortium responsible for this campaign consists of 26 astronomers from 21 institutes on 4 continents. The first results of this campaign will be published as a series of seven papers in the journal Astronomy and Astrophysics. More results are in preparation. For more information about this study, visit:
http://www.sron.nl/index.php?option=com_content&task=view&id=3277&Itemid=754
http://www.spacetelescope.org/announcements/ann1121/

Nice Specimen of a Crater. Click for larger. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Wow, look at this beautiful example of a crater.  It has a nice central peak and steep walls, unknown what the bright material is on the floor.

This crater has not been named although  I would imagine this crater will get some study and be named after a time.

The image was taken by the MESSENGER spacecraft’s Narrow Angle Camera so the resolution is very high, just 100 meters/pixel with the crater being about 22 miles (36 km) in diameter.

The crater is located at Latitude -54.33^o and Longitude 311.2^o

The Running Chicken Nebula by the ESO. Click for larger. Image credit: ESO

No really, that is what this is sometimes called; you may know it as the Lambda Centuri Nebula located 6,500 light-years away in the constellation of Centaurus. The Running Chicken moniker comes from some people seeing a chicken shape in the star forming region.

Read more about the nebula from the ESO website below and if you are wondering about the dark spots in the upper right of the image, those are called Thackeray’s Globules, click the Hubble link in the story below (both links take you off site):

In the nebula, which lies around 6500 light-years from Earth, hot newborn stars that formed from clouds of hydrogen gas shine brightly with ultraviolet light. This intense radiation in turn excites the surrounding hydrogen cloud, making it glow a distinctive shade of red. This red shade is typical of star-forming regions, another famous example being the Lagoon Nebula (eso0936).

Some people see a chicken shape in pictures of this red star-forming region, giving the nebula its nickname — though there is some disagreement over exactly which part of the nebula is chicken shaped, with various bird-like features in evidence across the picture [1].

Aside from the glowing gas, another sign of star formation in IC 2944 is the series of opaque black clumps silhouetted against the red background in part of this image. These are examples of a type of object called Bok globules. They appear dark as they absorb the light from the luminous background. However, observations of these dark clouds using infrared telescopes, which are able to see through the dust that normally blocks visible light, have revealed that stars are forming within many of them.

The most prominent collection of Bok globules in this image is known as Thackeray’s Globules, after the South African astronomer who discovered them in the 1950s. Visible among a group of bright stars in the upper right part of the image, these globules feature in a famous image taken by the NASA/ESA Hubble Space Telescope (link).

While Hubble offers greater detail in its image of this small area, the Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory captures a much larger panorama in its images, covering an area of sky roughly the size of the full Moon [2]. Much like a zoom lens on a camera lets a photographer choose the most appropriate field of view when taking a picture, the dramatically different viewpoints offered by different telescopes can offer complementary data to scientists studying astronomical objects which cover an extended area of the sky.

If the stars cocooned in Thackeray’s Globules are still gestating, then the stars of cluster IC 2948, embedded within the nebula, are their older siblings. Still young in stellar terms, at just a few million years old, these stars shine brightly, and their ultraviolet radiation provides much of the energy that lights up the nebula. These glowing nebulae are relatively short-lived in astronomical terms (typically a few million years), meaning that the Lambda Centauri Nebula will eventually fade away as it loses both its gas and its supply of ultraviolet radiation.

A couple of videos today.

The first is more about the Speed of Light being broken.  Yes I’m still skeptical, but interesting all the same.

Click here to view the embedded video.

The second is kind of a fun thing by an enterprising high school student in Nevada named Manuja Gunaratne.  He launched an aircraft with garbage bags.  I call it the “garbage bag aircraft”.  Funny becuase while I think this is great out here he’d be vilified something terrible – littering you know, plastic, danger to birds etc.  No really, I’ve heard officals lamenting publically about how the earthworms are not native – yeah they are more than a little out of control.

Anyways, way to go congrats to young Mr. Gunaratine and looking forward to your next project.  Here is the Project T.B.A.C website, do check it out, it’s pretty good.

The aircraft was outfitted with a camera and Manuja made a video out of the pictures so we get a time lapse of sorts:

Click here to view the embedded video.

The home planet and moon from the Juno Spacecraft on August 26, 2011. Click for larger. Image credit: NASA/JPL-Caltech/SwRI

The Juno spacecraft, launched on August 5, 2011 and enroute to Jupiter turned its camera towards the Earth and Moon on August 26, 2011.

At the time the picture was taken the spacecraft was already 6 million miles (9.7 million km) away during a instrument and subsystem check including the JunoCam.

When I saw the image the first thing I though of was “we don’t look so high and mighty do we” and that sort of sentiment is shared by Scott Bolton Juno principal investigator from the Southwest Research Institute in San Antonio:

“This is a remarkable sight people get to see all too rarely, this view of our planet shows how Earth looks from the outside, illustrating a special perspective of our role and place in the universe. We see a humbling yet beautiful view of ourselves.”

We’ve not seen the last of Juno yet, the trip to Jupiter consists of a couple of large “loops” and the spacecraft will get a gravity assist during a flyby of Earth in about two years (October 2013) before its eventual arrival at Jupiter in 2016.

Visit the Juno website at http://www.nasa.gov/mission_pages/juno/main/index.html

Via Ravyn Schmidt on Google+ comes this cute video about a man hoping to make a date to see a woman:

Adorable! But I have to wonder: why didn’t he just use Heavens Above instead?

[Edited to add: I almost forgot; the last bit in the video reminded me strongly of this.]

Looking for a change of pace? Your day-to-day, 9-5 job making you feel like you’re glued to the ground?

Then maybe you need a new job. And maybe you should talk to NASA: they’re looking for more astronauts.

The astronauts of the 21st century will help NASA through the next phase of space exploration as we continue the work of U.S. astronauts aboard the International Space Station in cooperation with our international partners; build a new NASA vehicle to enable human deep space exploration; and partner with industry to foster development of a commercial capability for human space flight to low Earth orbit.

NASA WILL ACCEPT APPLICATIONS IN THE FALL OF 2011 FOR AN ASTRONAUT CANDIDATE CLASS OF 2013.

I know some people will snark about this, saying why bother applying when NASA doesn’t even have a rocket to take humans into space? But that’s not the right way to think about this for several reasons:

1) NASA is planning on building a new rocket system;

2) NASA can hitch a ride with other countries like Russia until then (just as other countries did with us);

3) Private companies are building rockets, and you can be pretty sure NASA will pay to ride with them.

And of course training to be an astronaut isn’t like training to deliver pizzas^*. It takes years, so if you want to get into space later it means getting into training now. There are no guarantees, of course. But now you know where to start.

Tip o’ the spacesuit visor to Damaris Sarria.

^* … a job I had for several years, and which does have some superficial similarities to being an astronaut: you wear uncomfortable clothes, you’re away from your base a lot, and when you get home you smell vaguely of mozzarella.

Last year, with much ballyhoo, NASA held a press conference about a team of biologists claiming that they had found microorganisms that could use arsenic instead of phosphorous as a basis for biological processes.

However, it didn’t take too long before the work was under serious attack by other biologists. Some were snarky, others more reserved, but the message was clear: not too many professional biologists felt the arsenic claim held up to scrutiny. In fact, some said the research paper was so shoddy it should never have been published.

This whole event comes to my mind from time to time, and I’ve been meaning to revisit it. I’ll admit I’m a little embarrassed by how I participated in it — I reported it straight, writing up a blog post relaying what I had learned from the press conference and from reading the paper itself. I am not a biologist, so the details of the paper were beyond me. But being a scientist myself I could glean what I needed for a blog post, especially coupled with the comments from the press conference.

Or so I thought. As the criticism came in, and I looked into it more, I found myself agreeing with those who disagreed with the original findings. I’ll note that I can’t say for sure if the research was done poorly or not, but it has become more clear that the work itself needed more outside commentary before being released in a press conference at the level it was. My own mistake was trusting NASA PR to have vetted this thoroughly before holding the press conference, and not getting an outside opinion myself. I wrote a followup a few days later with my doubts.

The reason I bring all this up now is that PopSci recently posted an article about the lead scientist in the arsenic story, Felisa Wolfe-Simon. I read it yesterday, and felt that it was coming from an odd angle — as a personality profile on Dr. Wolfe-Simon it’s interesting, but as a background piece on the arsenic story itself it read to me as if it were slanted to support her.

Both my Discover Magazine colleagues Ed Yong and Carl Zimmer have a similar opinion — Carl is actually pretty blunt in his opinion on the article, giving details (and a timeline!) on where it goes astray. Wired Magazine blogger David Dobbs also write an interesting piece where at first he says he likes the article, then updates his post later saying that after more thought a lot of doubts arose. Given the size and impact this story had last year, I suggest you read those links. They’ll give you something to think about.

There are many lessons to be learned here, but the one I’ve walked away with is that since this story came out, I’ve been more careful to check with sources if I’m not familiar with the science myself (and even if I am familiar with it). It’s impossible to prevent all mistakes in writing science articles — in writing anything — but a healthy dose of skepticism is required to minimize them.

In fact, I’d say a healthy dose of skepticism is always required, in every situation. It’s a highly useful tool.

If you haven’t been tracking the arsenic life saga closely over the past ten months, check out Tom Clynes’s big feature at Popular Science. It focuses on the travails of Felisa Wolfe-Simon, the lead author on the paper, who has gone from the Olympian heights of TED talks to getting “evicted” from the lab where she’s worked for the past couple years. (Her word.)

For those of us who’ve been tracking the story for a while, that last fact popped out. Wolfe-Simon had been working in the lab of her co-author Ronald Oremland, but that’s now over. Let’s recall that her senior colleagues dubbed the intriguing microbe she studied GFAJ-1, for “Get Felicia A Job.”

It’s a good article. I won’t be forgetting the opening scene anytime soon, when Wolfe-Simon is ambivalently posing for a television crew, and she sinks into the mud of Mono Lake, where she first encountered GFAJ-1.

But I do share some of the reservations that science writer David Dobbs expresses over at his blog Neuron Culture. As a genre, the profile is one of the most addictive and enjoyable of all. It doesn’t matter if the profile is of a hero or a scoundrel; the story is good as long as it’s full of human nature in all its extremes. But profiles of scientists are tricky, because science transcends any single individual scientist. To do the science justice, you may need to pull the spotlight away and get into the less human stuff, like chemical reactions and pH levels.

The story thus focuses mainly on Wolfe-Simon, with scientific critics effectively reduced to mean chair-throwers, their scientific objections dispatched in a couple lines. People and events are relevant insofar as they affect Wolfe-Simon. And in the process, Clynes writes some mystifying stuff:

What made the level of criticism so extraordinary is that the paper, in itself, is not so flawed that it should not have been published. The argument was compelling, the conclusions were measured, the data was thorough, and the paper made it through the same peer-review process as other articles in Science.

And Clynes has us believe that this barrage of extraordinary, brutal criticism (or perhaps questions from journalists) forced Wolf-Simon and her colleagues to go into witness protection:

Overwhelmed with questions from the media, Wolfe-Simon went underground. Guided by NASA’s PR team, she and Oremland and the paper’s other co-authors began citing NASA spokesperson Dwayne Brown’s position that the authors would not be responding to individual criticisms. The agency, Brown said, didn’t feel it appropriate to debate science using the media and bloggers. Discourse should occur in scientific publications.

“I wasn’t hiding, but I didn’t want to get involved in a Jerry Springer situation, with people throwing chairs,” Oremland says. “There are hundreds of blogs some viable and some off the wall, and they all want an immediate response. To try to engage in scientific commentary that way seems like a descent into madness.”

What the–?

I’ve seen this version of the arsenic life story before, and I can say (as one of the people mentioned in Clynes’s story) that it simply does not square with the facts. I really hope it doesn’t get set in people’s minds like concrete.

Let’s just run through the timeline, shall we?

Thursday, December 2: An eagerly anticipated NASA press conference, the publication of the paper in Science, front-page news in leading newspapers, with no articles I’m aware of dealing seriously with the critics.

[Update: Friday December 3: Chembark, a chemistry blogger, declares, "I am not convinced."  Jim Hu of Texas A&M writes, "Could there be arsenic-based backbone in the DNA? Maybe. But it would be extraordinary and so I would like to see better evidence." I for one missed these posts.]

Saturday, December 4: Rosie Redfield, a microbiologist with a blog she mainly uses for her class, expresses deep skepticism. It is the only such blog post I know of that presented a detailed criticism at this point in the timeline. [Update--I should say, the only blog post I was aware of.]

Sunday, December 5: Alex Bradley, another microbiologist, guest-blogs at We Beasties in a similar vein. The criticisms are harsh but deal in the scientific details of the paper.

The audience for both posts is small–an audience of fellow microbe junkies.

By Sunday afternoon, I think it’s time to write something. I’m wondering if Redfield and Bradley are saying what a lot of other scientists are thinking. I start getting in touch with leading experts in the areas that the paper touches on. In the next couple days they will get back to me, and just about all of them say the paper has serious problems, one simply declaring it should never have been published.

Naturally, it’s only fair to give the authors of the study a chance to respond. So on Sunday afternoon, I send links to the two blog posts above to Oremland and Wolfe-Simon. Oremland promptly writes back, “Sorry, but ‘nope.’”

I’m a bit surprised and email back to find out why. Here’s what I get:

It is one thing for scientists to “argue” collegially in the public media about diverse details of established notions, their own opinions, policy matters related to health/environment/science.

But when the scientists involved in a research finding published in scientific journal use the media to debate the questions or comments of others, they have crossed a sacred boundary.

Monday, December 6: Wolfe-Simon emails back at 12:42 AM, a few hours after I emailed her. She cc’s all her co-authors and administrators at NASA, including the director of the astrobiology program:

Mr. Zimmer,

I am aware that Dr. Ronald Oremland has replied to your inquiry. I am in full and complete agreement with Dr. Oremland’s position (and the content of his statements) and suggest that you honor the way scientific work must be conducted.

Any discourse will have to be peer-reviewed in the same manner as our paper was, and go through a vetting process so that all discussion is properly moderated. You can see many examples in the journals Science and Nature, the former being where our paper was published. This is a common practice not new to the scientific community. The items you are presenting do not represent the proper way to engage in a scientific discourse and we will not respond in this manner.

Regards,
Felisa

In the morning I get busy on my story. That evening, the CBC comes out with a story focused on Redfield’s complaint, relaying NASA’s statement that it’s not appropriate for scientists to debate each other in the media. I scratch my head and get back to work.

Tuesday, September 7: I publish a story in Slate about arsenic life, describing the detailed criticisms of a number of scientists (which I’ve posted in full on the Loom). I quote the no-comments of Oremland and Wolfe-Simon.

—Now, we can have a fine debate about whether journalists should ask scientists to respond to criticism from other scientists about their work. Oremland and Wolfe-Simon may truly believe that this crosses a sacred boundary. I say it doesn’t. It’s standard practice. Science, where the arsenic life paper was published, lets reporters get their hands on papers early, and reporters regularly seek out other scientists for comments on those papers before publishing their articles. If two scientists post their thoughts on public blogs, there is no difference in asking authors of a paper to respond to their critiques. Trying to make such a distinction is pointless.

I’ve been doing this kind of thing for a long time, and I have never encountered a response like this one from the hundreds of scientists I’ve interviewed. And that includes scientists who work for or are sponsored by NASA, despite the claims that popped up that NASA policy forbids such open debate. In fact, the scientist who gave me the headline for my story–”This Paper Should Not Have Been Published”–is herself part of NASA’s astrobiology team. Did she say, “Mister, you’ve crossed a sacred boundary”? Nope. She wrote me a long, detailed explanation of why she thought the paper failed.

In other words, I’m pretty sure I’d win that debate.

But the story you get from Clyne and others is not that Oremland and Wolfe-Simon had some a priori policy never to deign to comment on criticism that weren’t published in a scientific journal. It’s that they were overwhelmed by Jerry Spinger-grade hordes of unseemly scientist bloggers and relentless journalists–so overwhelmed that they had to vanish. They were victims.

But for this version of events to be true, the hordes must have stormed their lab in a single day–at some point between Saturday, when Redfield posted her critique, and Sunday, when the scientists told me they wouldn’t comment for the story. As far as I can tell, there were just two blog critiques published during that time, and a CBC news article. If someone can point to any evidence of this alleged horde that I’ve somehow missed–perhaps the gnawed bones of some graduate student left in its trail–I’d love to see it.

Otherwise, this just seems like one of those stories that sounds good in hindsight. And if any good is going to come out of this strange saga, we should strive to get all its stories straight.

[Update: Clynes responds.]

The folks at Wired recently asked me to put together a guide to the human ecosystem. You can get it in the October issue as a centerfold–the kind of centerfold that shows someone who took off the clothes, and then took off the skin. Bugs in your eyes, in your ears, in your gut, influencing your mind and health–they’re all there. Check it out.

Two mice run headfirst into one another in a narrow plastic tube that isn’t wide enough for both of them. One of them must give way. In their earlier encounter, the first mouse exerted its dominance by forcing its rival to reverse down the tube. This time, things are different; the second mouse pulls rank and the first one backs down.

Mouse hierarchies don’t change this readily, but the second mouse has been given a boon by Fei Wang at the Chinese Academy of Science. By injecting a single gene into one part of its brain, Wang turned the subordinate animal into a dominant one.

The gene that gave the mouse a burst of social mobility is GluR4. It creates part of a protein called the AMPA receptor, which allows signals to flow quickly between two neurons. By injecting extra GluR4 into a mouse’s brain, and producing more AMPA receptors, Wang strengthened the connections between its neurons. The effect is like building expressways between two cities overnight – you can have a much larger and faster flow of traffic between them.

Wang injected the extra GluR4 into a part of the rodents’ brains called the medial prefrontal cortex (mPFC), which has been linked to social rank. As early as 1986, scientists showed that rats lose their social status if they suffer injuries to their mPFCs. Wang himself found that the mPFC’s neurons signal more strongly to one another in dominant brains than in subordinate ones.

By manipulating this signalling, he could push mice up or down the social ladder. With an extra dose of GluR4, the mice gained social standing. When they confronted other mice in a cramped plastic tube, they were more likely to force their rivals to retreat, even if they had previously given way. With their new rank, they were also more likely to court female mice with high-pitched ultrasonic songs.

On the flipside, Wang managed to lower the rodents’ rank by injecting them with just a small fragment of GluR4 (GluR4Ct). On its own, this fragment scuppers AMPA receptors and weakens the communication lines between the mPFC’s neurons. This time, the newly subordinate mice were more likely to give way to individuals that they had previously bested, and they were less likely to sing to females.

How could changes in the brain of one animal affect its standing among its peers? Wang thinks that the answer lies with the mPFC. Among other roles, this region has been linked to social behaviour and hierarchies, in humans as well as mice. When computer gamers think about players who are better than they are, their mPFCs light up.

The mPFC acts like a control centre for social interactions. It exerts influence over other parts of the brain that release hormones and signalling chemicals, which affect everything from aggressiveness to fear. If you change the strength of the signals in the mPFC, the effects would ripple out across the brain. Perhaps the mice become more aggressive; maybe they become less fearful. Wang is now looking at which of these effects accounts for the rise and fall of the rodents’ ranks.

We’ve known that animals form dominance hierarchies for around a century. In 1921, Norwegian scientist Thorleif Schjelderup-Ebbe discovered one of the first examples of these hierarchies in chickens, which is why they’re more commonly known as pecking orders. They’re a vital part of animal life. An individual’s rank can drastically affect its access to mates, food and shelter. These ranks emerge very early (you can see them in two-year-old children) and they change very slowly, if at all.

But very few people have looked at how different social ranks are manifested in the brain. Wang has not only started to do that, but he has shown that manipulating the brain can actually change a mouse’s rank. It would be fascinating (and probably experimentally tricky) to see if the same trick would work in humans. It is unlikely though, especially since our social structures are much more complex. For a mouse, it’s enough to give it an extra gene that makes it pushier. We have wealth, reputation, contacts, education and discrimination to contend with.

Reference:
Wang, F., Zhu, J., Zhu, H., Zhang, Q., Lin, Z., & Hu, H. (2011). Bidirectional Control of Social Hierarchy by Synaptic Efficacy in Medial Prefrontal Cortex Science DOI: 10.1126/science.1209951

I know I just posted a MESSENGER photo of craters, but this one is different and spectacular enough that I figure, why not? I love a big, splashy, wide-angle shot of a rayed crater! So here’s the lovely, 80-km wide impact crater Debussy on the surface of Mercury:

[Click to haphaestenate.]

Craters make rays when the ejected material blasted out forms long plumes which fall across the surface. On airless worlds, those trajectories are ballistic, heading straight out from the center of the impact. Deeper material tends to be a lighter shade than surface material, so the interior of the crater and the rays are lighter than surrounding surface stuff. You can also see what’s called the apron, the layer of material that falls immediately around the crater, surrounding it (that’s more clear in an earlier image of the crater looking more straight down on it).

Rayed craters are common (even on our Moon; take a look at Tycho!), and usually indicate the impact was recent (geologically), since the rays eventually get eroded by the solar wind, cosmic rays, and subsequent meteorite impacts. Debussy is therefore one of the younger features on Mercury. It still has that youthful shine.

Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Let’s just pretend for a moment that this theater is showing a thrilling movie about Cambrian fossils, shall we? And to further that dream, join me in October for “Celluloid Science,” a talk about science and the movies at the New York Academy of Sciences. It’s part of the NYAS “Science & The City” series.

Here are the details from the event web site…

Celluloid Science: Humanizing Life in the Lab
Thursday, October 20, 2011 | 7:00 PM – 8:30 PM
The New York Academy of Sciences, 7 World Trade Center

If you know anything about science, you understand that it is a highly complex human endeavor that mixes perseverance and luck, eccentricity and training, feasts and famines. As a medium, film has the potential to bring us into the inner world of science, breaking down misconceptions about the nature of science by creating an alternative narrative.

Science & the City teams with the Imagine Science Film Festival (ISFF) to present a panel discussion about telling the stories of science through film. Moderating this panel will be author Carl Zimmer. On the panel will be Sean Carroll, PhD (evolutionary biologist and founder of the Howard Hughes Medical institute’s Documentary Institute); David J. Heeger, PhD (neuroscientist who studies the brains under the influence of cinematic stimuli); Darcy Kelley, PhD (biologist at Columbia University); and Valerie Weiss, PhD (scientist and award-winning writer and director, Losing Control).

It’s a ticketed event, but you, my dear Loominaries, can get $15 off full-price tickets by using the promo code SPKR15. Register here.

[Image: Photo by Kevin H./Flickr] 

I’ve known Dan Durda since college. We went to Michigan together, studying astronomy. He wound up getting into asteroids and exoplanets, and may yet be part of a team that will save the Earth from an impact.

A few years back, he started dabbling in art, and discovered he was good at it. In fact, I’d say he’s really good at it. His stuff has graced magazine covers and articles, and even this blog (see the Related posts section below).

See what I mean? His stuff is crazy beautiful.

And now you can own it. He’s created his own CafePress store where he’s got some of his work as prints. You can also get a 2012 calendar (yes, it goes all the way through December; Dan and I are both real astronomers) called "All These Worlds…", with some breathtaking artwork.

He also has a gallery of his work online you should check out simply because it’s fantastic. Through Dan I’ve met quite a few space artists, people whose work I have respected for many years. And they all get this look in their eye when they talk about Dan; they’re impressed by him.

OK, enough gushing. Go take a look, and enjoy. I’m pretty sure you will.

At 2pm today, in a field not far from downtown Chicago, a final proton will smash into an antiproton. And then the Tevatron, the most powerful particle accelerator for almost three decades, will be shut off after producing over 500 trillion proton-antiproton collisions (over 10 inverse femtobarns). The Tevatron discovered the top quark, the Bc meson, and the tau neutrino. It measured direct CP violation, constrained the possible mass of the Higgs, precisely measured a range of masses and lifetimes, as well as a host of other important scientific contributions. It was a remarkable machine, but it has now been superseded by the Large Hadron Collider.

Science marches on, and after a glorious career, it is time for the Tevatron to go dark. Fermilab is throwing a goodbye party.

You don’t just throw a switch and turn off a particle accelerator. The process is slow and deliberate. The superconducting magnets will take roughly a week to warm back up. And the data will take many months to analyze. But at some point tomorrow afternoon North America will witness its last controlled TeV particle collision.

What’s the News: Along with a whole passel of new Kindles, Amazon yesterday announced a new browser to accompany them, named Silk. And it’s got some unusual characteristics that have some crowing about the next big thing in mobile browsing and others wondering about privacy implications.

How Does It Work:

• Silk, according to statements by the company (check out the video above), is a browser that uses Amazon’s massive cloud computing resources to relieve the processing burden on its Kindle Fire tablet, resulting in super-fast page loading.
• When you go to a webpage on the tablet, Amazon’s remote servers, rather than the processor on the tablet, go forth and assemble all of the pictures, style sheets, HTML, and other gear that your browser usually needs to go track down by itself. Then the servers send that information to the tablet, accomplishing the task much quicker than a normal browser.
• Silk also keeps track of where you tend to go and caches images, style sheets, etc., so frequently visited pages load faster on the device.
• For a detailed-yet-accessible rundown of Silk’s backend, check out Ryan Paul’s piece at Ars Technica.

Haven’t We Heard Something Like This Before?

• Indeed we have. The Norwegian software company Opera released a mobile browser in 2005, Opera Mini, that does the same basic thing, although it compresses the pages when sending them back to the device. Opera is also the company that pioneered tabbed browsing.
• An Opera spokesperson had some wry remarks congratulating Amazon for ‘catching up’ when he spoke to TechRadar after the release:

“You know, we’re a huge player in this field,” Opera’s Phillip Grønvold told TechRadar. “With more than 128 million users each month using Opera Mini it is clear the market for cloud based computing is in rapid growth. Each month we are adding millions of users who are participating in the Web and we feel good that other big time players like Amazon are catching on to the idea.”

What About Security:

• Hmm, a browser that watches everything you do, recording your habits and putting them on a cloud belonging to the largest online retailer? That sets a few people’s alarm bells ringing, especially since security is a serious bugaboo in cloud computing.
• The best exploration we’ve seen of what Silk means, both in terms of tech and in privacy, is at the Talking Points Memo Ideas Lab, which spoke to Rebecca Jeschke, media relations director at the Electronic Frontier Foundation. One of the primary concerns, at least from early media reports of what the browser does, is that Amazon would seem to have more access to user data than even ISPs do.

“They key here is that Amazon appears to be keeping a record of everything you do online,” Jeschke explained, “Web surfing habits say a lot about you; what your family situation is like; what your health situation is like. It is pretty intimate information about your life. And if someone is collecting it, there’s always the chance someone going to see it, whether that’s justified or not, whether it’s accidental or on purpose.”

• But not very many people have gotten a chance to poke around in Silk’s guts yet, so a deeper analysis will have to wait.

The Future Holds:

• The Kindle Fire, with Silk installed, will start shipping on November 15th. At that point, we’ll hear more on what people think of the browser—and what security concerns there might be.
• So far, Silk is only available on the Fire, but there are some hints that it may make its way to other devices, according to some detective work by Christopher Mims and others. Buried in the Fire’s privacy notice is this line:

If you use Amazon Silk on a Kindle device, your device will automatically send Amazon Silk crash reports to Amazon. You may choose to send these reports when using Amazon Silk on other devices. Crash reports help us diagnose problems with the browser and improve its performance.

Twitter is either an indispensible professional and personal tool, or the downfall of humanity, depending on who you believe. But to Scott Golder and Michael Macy from Cornell University, it is something more: an unparalleled source of data. The duo has used the popular social networking site to eavesdrop upon the world’s moods, as they rise and fall throughout the day and across the week. By analysing half a billion tweets from 2.4 million people in 84 different countries, they turned Twitter into a giant global mood ring.

They found that, on average, people wake up in a good mood, which falls away over the course of the day. Positive feelings peak early in the morning and again nearer midnight, while negative feelings peak between 9pm and 3am. Unsurprisingly, people get happier as the week goes on. They’re most positive on Saturdays and Sundays and they tend to lie in for an extra two hours, as shown by the delayed peak in their positive feelings. The United Arab Emirates provide an interesting exception. There, people work from Sunday to Thursday, and their tweets are most positive on Friday and Saturday.

This might seem obvious, but previous studies have arrived at conflicting results about our mood cycles. For example, psychologists have variously said that positive feelings peak: just once, 8 to 10 hours after waking; once at noon and once in the evening; and once in the afternoon and again in the evening. Different studies have also claimed that negative feelings are most common in the morning, afternoon or evening… or don’t have any daily cycles all!

Most of these studies involved small numbers of American undergraduates, who were asked to remember their feelings hours or days ago. These small samples and imprecise measures might explain why the results have been so inconsistent. On top of that, students are hardly representative of the wider population, especially since they’re constrained by academic schedules.

Twitter was an obvious way of circumventing these problems. It’s popular around the world, people use it to voluntarily report their feelings without any reminders, and they do so in a timely (and time-stamped) way. The experimenters don’t ever have to prompt or even meet their volunteers. They just sit back and collect the data.

This is the second study to use Twitter to track broad changes in mood. The first focused solely on the United States and although widely reported last year, it has not been published yet.  Golder and Macy’s attempt is larger in scope. They sampled 400 English tweets from every Twitter account created between February 2008 and April 2009. The messages – around 509 million of them – spanned two years.

The duo analysed them with a programme called Linguistic Inquiry and Word Count (LIWC), which hunted for words that betray a number of different positive and negative feelings. The programme’s vocabulary is calibrated using texts from journals, novels, conversation recordings, blog posts and more, in both American and British English. It may not be up-to-date with the latest internet slang, but it’s certainly diverse in its scope.

You might think that counting positive and negative words is a fairly crude way of looking at tweets. For example, the programmes might recognise “good” as being positive, even if it was part of a neutral phrase (“good morning”) or a negative one (“not good”). But Golder and Macy found that both of these misdirecting uses are far less common than people might assume, and certainly too rare to skew the results. For example, “good” appears in 1 in 20 tweets, but it’s only preceded by “not” in 1 in 2000 of them. Likewise, including smileys and emoticons did little to change the shape of the world’s moods.

The mood graphs suggest that sleep gives us a chance to reboot our moods from the stress of a working day, and weekends are doubly refreshing for our emotions. And people show the same emotional cycles around the world even though they might come from different cultures and countries (including the UK, USA, Canada, India, Australia, New Zealand and various African nations).

By looking at when people were most likely to tweet, Golder and Macy separated their sample into morning people, afternoon people, evening people and night owls. The first three groups were fairly similar in their mood cycles, but the night owls – who were most active between midnight and 6am – were very different. Their morning peak of positivity happened two hours after everyone else and they didn’t have a second peak at night. Instead, they had two peaks of negative feelings – once in the morning when everyone else’s negative feelings are ebbing, and another later at night.

Golder and Macy also looked at how the tweets varied with the seasons. The length of the days had no effect on their emotional content; instead, it’s the relative change in daylight hours that matter. Our tweets are (very slightly) more positive at the spring equinox, when the days start to lengthen more quickly, than at the summer solstice when the days are actually at their longest. Negative feelings, however, don’t seem to change with the seasons. The fabled “winter blues” are more due to fewer positive feelings than more negative ones.

Relying on tweets raises its own problems, but this is still a decent step beyond small, questionnaire-based studies. Twitter’s users are not representative of the general population, but they certainly represent a broader spectrum of society than American college students. Tweets only show the emotions that people are willing to express, rather than the ones they actually feel, but you could say the same for the questionnaires used in most psychological experiments.

The data set is not perfect, but it compensates for that in its size and breadth. Looking at the world’s moods may be a simple first step, but Golder and Macy have demonstrated how scientists can mine social networks for data on those slipperiest of experimental subjects: people.

Reference: Golder & Macy. 2011. Diurnal and Seasonal Mood Vary with Work, Sleep, and Daylength Across Diverse Cultures. Science http://dx.doi.org/10.1126/science.1202775

This week, women in Saudi Arabia were given the right to vote and to run for municipal office.

First off, this is fantastic news. Saudi Arabia is one of the more repressive countries for women, so to see them taking this major step is, well, wonderful! King Abdullah has been making small steps towards reform for years. While I want to see women have full rights everywhere on Earth, I understand the political need to take it slowly in Saudi Arabia. It’s a very conservative religious country, and the backlash if things move too quickly could be extraordinary.

There’s much left to do, of course. Women still have a long way to go there; they are not allowed to drive or to leave the country unaccompanied, for example. But this is the right way to move. I just hope that vector stays pointed true.

I also want to relate my own thinking when I first read this news. My initial thought was snark; Welcome to the 20th century was literally the first thing I thought. My second thought was what I wrote above about this being fantastic news.

My third thought was the most interesting to me. It was contrition: in the United States, a country where we pride ourselves on being modern and forward-thinking (usually), women didn’t get the vote until 1920 — nationally, at least; at the local and state level those rights were slowly being granted for years.

So 90 years ago, women here in the US didn’t have the right to vote, and we weren’t (officially) a religious kingdom. Just to put how big a deal this Saudi Arabia news is into perspective.

We still have lots of progress to make here in the States, too. But it’s nice to know that even in places like Saudi Arabia, progress can be made.

However, just to be clear, keep in mind just how far we have to go: in Pakistan, a girl is making news because her family refuses to have her killed, as is customary, because she was raped. Honor killings, as these are called, are still quite common.

So. I’ll just leave you with this.

Artist’s rendering of the Tiangog-1 docking
with another craft.

Today, with much fanfare, China launched its Tiangong-1 space craft into orbit from a site in the Gobi Desert. The unmanned craft is set to dock with later Chinese ships, allowing engineers to practice and experiment with the techniques they’ll need to assemble the space station China plans to build by 2020. Reports from earlier this year suggested that the Tiangong-1 will be converted to taikonaut living quarters in the station, but more recent news indicates that it will be primarily a testing device. For more details about China’s space station dreams, including scientific goals, questions about the military’s intentions, and more, check out our coverage here.

Image courtesy of Xinhua News Agency

A paper has been accepted for publication in a science journal (PDF) where the author has analyzed data from NASA’s Kepler planet-finding observatory, trying to figure out how many Earth-sized planets there might be in the galaxy orbiting their stars in their habitable zones; that is, at the right distance so that the star warms the planet enough to have liquid water. In the paper, he estimates that on average 34% (+/-14%) of Sun-like stars have terrestrial planets in that Goldilocks zone.

34%!

I can explain how he got this number. But I can also explain why I think this needs to be taken with a grain of salt. Let me be clear: it’s possible he’s right, and I suspect he may very well be. His math looks good to me. But a couple of assumptions he had to make need to be pointed out, and I want that to be clear before the media start running around saying there are billions of Earths in the galaxy based on this.

Here’s the deal. Kepler is an orbiting observatory that’s staring at about 100,000 stars, looking for dips in their light when an orbiting planet passes in front of them from our perspective. The length of time the dip takes gives us the orbital period of the planet, and the size of the planet (if the star’s size is known, generally true) can be determined by how much light is blocked. I talk about how this works in a little more detail in an earlier post.

The astronomer, Wesley Traub of Caltech, based his analysis on only the first few months (136 days) of Kepler data, what was available at the time. This introduces a bias into the calculations, because that length of time is too short to conclusively find planets in their stars’ habitable zones! Even being generous, the length of such an orbit is at least 200 days, much longer than the Kepler sample. So he was forced to look at only short-period planets (with periods of 42 days or less), much closer to their stars, and extrapolate the data from there. I’ll note that Dr. Traub was up front about potential biases in the data and his analysis.

He looked at stars similar to the Sun (with a range from somewhat hotter to somewhat cooler, roughly F, G, and K stars). He then looked at data for all planets detected — terrestrials (Earth-sized), ice giants (like Uranus and Neptune), and gas giants (like Jupiter), getting their size and orbital period.

Then he found the ratio of terrestrial planets to all the planets seen. Again, remember, this ratio was found for planets somewhat close in to their stars.

Then he plotted all the planets versus distance from their parent stars. For example, you see very few planets very close to the star (probably because it’s hard to form or get a planet to orbit that close in), then more as you get farther out, then fewer at some large distance (which may, once again, simply be due to the fact that planets with long orbital periods can’t be seen in the short duration of the data). He then found an equation (called a mathematical fit) that did a good job predicting the shape of the plot. Once he had that, it’s easy enough to extrapolate it out to the distance of the habitable zones of the stars.

That gave him an estimate of all planets orbiting there, including gas and ice giants. Multiply by the ratio of terrestrial planets, and boom! 34% of stars like the Sun should have planets that are Earth-sized orbiting them at the right distance.

The thing that makes me most uncomfortable is that he had to use those short period planets, and extrapolate outwards. Extrapolation is always dangerous because you can’t be sure your fit behaves well outside the range in which you calculated it. For example, imagine you took a census of 1000 people ages 0 – 17, and made a fit to their height versus age. You’d find their height gets bigger with time, in general. But if you extrapolate that out to someone who is 40 years old, you might estimate they’ll be 4 meters tall!

We don’t know very well how planets form in their solar systems, and how they move around after. It may be that nature doesn’t make many planets in the habitable zone. Or maybe it does, but after some amount of time the planets move out of it, maybe through gravitational interactions with other planets. I’ll note that our own solar system makes that seem unlikely; we do have three planets in the Sun’s HZ!

So what are we to make of all this? I think Dr. Traub did careful, interesting work, and his number of 34% is probably not terribly far off. Again, we should keep our eyes on that number, since it’s based on extrapolation, but the calculation that went into it is well-reasoned. I wouldn’t be surprised if he’s pretty close to the mark.

And what does this mean for you, the science enthusiast? Well, F, G, and K stars comprise very roughly a quarter of the stars in the Milky Way, or something like 50 billion stars total (again, I’m being really rough here). That means, assuming Traub is correct, there could be 15 billion warm terrestrial planets in our galaxy alone!

Interestingly, last year I wrote about how another estimate indicated that 1/4 of Sun-like stars might have Earth-like planets. That’s not far from Traub’s ratio, and that 2010 study used different techniques on different stars! Not conclusive, but interesting.

I’ll add that I think this work was worth doing even this early on in the Kepler mission. This is a great first step in analyzing the massive amount of Kepler data, and putting a number on it that we really want to know. As time goes on, and Kepler sends back more observations, Traub’s work will have paved the way to work on planets with bigger orbits. I’ll be very, very curious to see which way that number moves as more data come in.

Image credit: Dan Durda; ESO/M. Kornmesser; NASA. Tip o’ the dew shield to Technology Review.