I was at the bookstore today and noticed that Evolution—the Extended Synthesis, edited by Massimo Pigliucci and Gerd B. Müller, was pretty affordable for an academically oriented work. I think readers of this weblog will find many of its chapters of interest (the Amazon review was pretty weird by the way, and I don’t think it reflects the book very well).

Okay, I know several people who have been waiting for me to get off my duff and talk about the speed of light.  This is Frank’s post, since he solved the riddle first Saturday.

To just blurt it out, the-speed-of-light-is-exactly-299,792,458-meters-per-second-in-a-vacuum.  That means that light will travel 299 million, 792 thousand, 458 meters in a second.  That’s about 300,000 kilometers per second, and about 186,000 miles per second.  The speed of light has been fixed with the increased accuracy of the definition and measurement of the meter.  The meter is defined as the distance light will travel in a vacuum in 1/299,792,458ths of a second.

Doesn’t that just give you goose bumps?  Take a look at this:

This is to scale. As you watch it, about 1.25 sec will pass as the little beam of light goes from the Earth to the Moon. That's how long it really takes.

To understand the speed of light, it might help to understand what exactly light is.  And what it is not.  I’m not going into the history of light, because I think everybody deserves to sit in college philosophy classes and suffer (I had to).  You go read Aristotle, I’ll read Einstein.  Believe it or not, there have been theories on the subject of light since the 6th century BCE.  As early as this the ancient Hindus were kicking around atomic theory.  By the 5th century BCE the Greeks were jumping in with some pretty interesting theories.  By 55 BCE, Lucretius (a Roman) wrote:

“The light & heat of the sun; these are composed of minute atoms which, when they are shoved off, lose no time in shooting right across the interspace of air in the direction imparted by the shove.” – On the nature of the Universe

Remember, this was 55 BCE.  There wasn’t anything even close to a telescope hanging around at the time.  This is also an interesting attempt to nail the concept of light down to the physical world, and get it out of the realm of religion.  Unfortunately, 55 BCE is believed to have been the year of Lucretius’s death (at the age of 43), so perhaps it didn’t work out so well for him.

Light exists as a wave-particle duality.  This isn’t really that special, because all matter is believed to exist in the same state of duality.  This whole concept is the foundation of quantum mechanics, and you’re just going to have to trust me here.  Just imagine a tiny little packet called a photon traveling through space as a wave, and you’re there.  That’s light.  What you “see” is only how your brain interprets the nerve impulses which have been fired by the photons.  You know that light exists much wider, deeper, and larger than we can see without some seriously expensive equipment.  Here is what you don’t see:

Light spectrum by Philip Ronan, all rights reserved.

There have been several good attempts to measure the speed of light through history.  In 1676 Danish Physicist Ole Romer used a telescope to watch the motions of Jupiter and Io, and calculated that it took 22 minutes for light to traverse the diameter of the orbit of the Earth.  Of course, nobody knew the size of the diameter of the orbit of the Earth.  If they had, Ole’s calculations would have set the speed of light at 227,000,000 m/s.  I have to say, that’s a pretty decent working hypothesis.

Several things are believed to be apart from the speed of light “speed limit”; most interestingly tachyons and quantum entanglements.  In the case of quantum entanglements, since you can’t pin down the exact position of a subatomic particle at any given moment, no information or mass is actually transmitted, therefore it doesn’t violate the speed limit (gotcha!).  Tachyons are tiny little critters, hypothetical really, that are limited to the space portion of the energy-momentum graph.  They can’t go slower than too fast, in other words.  They lose energy and cease to exist.

What you do see, by Ibrahim Lujaz, all rights reserved.

I’m sure as our knowledge of the universe around us increases, we’ll get a better understanding of light, it’s speed limit, and what is or is not bound to it.  I’ve been told that for every “law”, there is something which exists outside of it.  Thanks, Frank.

What pairs well with chocolate? A pricey tablet computer, of course.

Stefan Magdalinski debated what to get for his sweetheart for her June birthday. Eventually, he decided on a candy Apple: He ordered his wife a chocolate-covered iPad.

As told on Magdalinski’s blog and reported by Mashable, what makes this feat more impressive is that he orchestrated the gift’s shipment from the U.K. to South Africa, calling two friends at a British chocolatier with an unusual question:

“Could you freeze an iPad in chocolate carbonite, and have it survive?”

The proof is in the chocolate. A gift that involved both an interesting customs discussion and a very confused wife ended in sweet success. Magdalinski: “no iPads were harmed in this production.”

Counting your calories? Other iPad combinations might better fit your tastes. As described on the blog CrunchGear, nostalgic Apple-users have gutted older computers to give them a new, touchable face.

And for those that want to hearken back a bit further, the blog Gizmodo recently described another iPad vision almost as romantic as chocolates, an iPad typewriter.

Luckily, none of these combinations required blending.

Related content:
Discoblog: Will The iPad Blend? Watch and Find Out.
Discoblog:  iPad Arrives—Some Worship It, Some Critique It, HP Tries to Kill It
Discoblog: Hey Baby, Wanna Come Over and Try My New iPad?

Images: Ahead Robot / Stefan Magdalinski

OMFSM.

First, there’s going to be a remake of "Fright Night", an actually pretty good vampire flick from the 1980s. I’m generally opposed to most remakes, but I think that this isn’t such an awful idea, since the premise itself is a good one. However, the remake’s director is the same guy who did "Lars and the Real Girl", which was… well, I’ll just say I didn’t like it and leave it at that.

But…

Guess Who they tapped for the part of Vincent, the fey late-night movie host who winds up becoming a real vampire hunter? David Tennant!

Oh yeah. I’ll watch that. The original role was played by Roddy McDowall, who was great. Tennant is a pretty good fit to that role, too.

Given who played the original role, I wonder what’s next for Tennant after this? I’m thinking Cornelius in a "Planet of the Apes" sequel. Ook ook.

Knowing something like the back of your hand supposedly means that you’re very familiar with it. But it could just as well mean that you think it’s wider and shorter than it actually is. As it turns out, our hands aren’t as well known to us as we might imagine. According to Matthew Longo and Patrick Haggard from University College London, we store a mental model of our hands that helps us to know exactly where our limbs are in space. The trouble is that this model is massively distorted.

To keep track of where your various body parts are, your brain maps your posture by processing information from your muscles, joints and skin. Close your eyes and move around a bit, and you’ll still have a good idea of what position you’re in even if you can’t see or touch yourself. But there’s no such direct signal that tells your brain about the size and shape of your body parts. Instead, your brain stores a mental model with those dimensions mapped out.

To visualise this model, Longo and Haggard asked volunteers to hide their hand under a board and use a baton to indicate the position of ten landmarks – the tip and base knuckle of each finger. Their answers were surprisingly inaccurate.

They underestimated the lengths of their fingers by anywhere from around 5% for their thumb and over 35% for their ring and little fingers. In contrast, they overestimated the width of their hand by around 67%, and particularly the distance between their middle and ring knuckles. Our mental hand is a shorter, wider version of our real one. Longo and Haggard found the same thing if they asked the recruits to angle their hands at 90 degrees under the board, and if they tested the right hand as well as the left.

These distortions actually reflect how sensitive each part of the hand is. The skewed mental map is remarkably similar to another map called Penfield’s homunculus, which charts the areas of the brain’s somatosensory cortex (the bit that processes touch information) that is devoted to each body part. Regions that have a more acute sense of touch correspond to larger parts of the homunculus, but they also loom bigger in our mental map. Regions that are less sensitive are smaller on both charts.

As we move from the thumb to the little finger, our digits become less sensitive and the mental map increasingly underestimates their true size. The back of the hand is more sensitive to movement across it than movement along it; accordingly, our mental map depicts a wider, shorter hand.

And we have no idea about this. Consciously, the volunteers had a pretty good appreciation of the size and shape of their hands. When Longo and Haggard showed them a selection of hand images and asked them to select the one that best matched their own, they did so very accurately. But even though they passed this test, they still failed to place the baton in the right place when their hands were hidden.

If we hold such a distorted depiction of our own hands, how is it that we ever grasp things successfully? It’s possible that our motor system uses a different model but Longo and Haggard put forward two more plausible ideas: that cues from vision are strong enough to override the warped map; and that we learn to correct for the misshapen model. Only by removing both of these factors did they finally reveal how skewed our perceptions actually are.

Reference: PNAS http://dx.doi.org/10.1073/pnas.1003483107

Image: Hands by Toni Blay

More on perception:

• How our skin helps us to listen
• How wearing a cast affects sense of touch and brain activity
• Blind man navigates obstacle course perfectly with no visual awareness
• Pain in the eye of the beholder
• Brain treats tools as temporary body parts

Two scientists went looking for water on Mars. After closely studying the Martian terrain, they think they might have found it–covering about a third of the planet, 3.5 billion years ago.

In a study published yesterday in Nature Geoscience, Gaetano Di Achille and Brian M. Hynek detail their hunt, which included looking at data from NASA’s Mars Orbiter Laser Altimeter (MOLA), a probe that studied the topography of the planet’s surface for four and a half years, starting in the late 1990s.

Scientists have debated whether Mars once supported oceans for over two decades, and, as the authors claim in their study’s abstract, these oceans remain one of the “largest uncertainties in Mars research.”

The authors of this study, who started out speculating on how water might have formed the apparent deltas and valleys on the planet, eventually looked at the altitudes of these features to determine if they could have been linked to a large body of water.

Gaetano Di Achille and Brian Hynek … had been building a database of Martian river deltas and valleys to examine how they might have been eroded by water, but ultimately realized that they had enough data to tackle the bigger picture. “Our research started as kind of a joke,” says Di Achille. “We were working on this database of deltas and valleys, and we said: why don’t we try to check this ocean hypothesis?” [Nature News]

They found that 17 of 52 deltas were at the same height, which might imply that they fed the same body of water which could have once filled a basin on the Northern hemisphere of the planet. Given that basin covers about a third of planet’s surface, the paper’s author question if these deltas might have channeled water into an ancient Martian ocean.

“If Mars had an extensive hydrological cycle in the past, with rain, groundwater reservoirs, ice sheets and surface run-off towards lakes and possibly a northern hemisphere ocean, then there should be evidence of deltas ringing the margins of these lowlands at a common elevation,” said Mr Di Achille. “Likewise, river valleys draining into such an ocean should also flow down to the same elevation, and shouldn’t be found below this level.” [Australian Broadcasting Corporation]

The research compliments another study from Hynek, which also looks at these river deltas.

In a parallel study published in the Journal of Geophysical Research (Planets), Hynek and colleagues catalogued some 40,000 river valleys on Mars, four times the number previously suspected. “The abundance of these river valleys required a significant amount of precipitation,” Hynek said. “This effectively puts the nail in the coffin regarding the presence of past rainfall on Mars.” [AFP]

Still, many hope for more direct evidence before claiming that this solves the ocean debate.

Taylor Perron, a geologist at the Massachusetts Institute of Technology in Cambridge, says that the result “strengthens the argument in favour of oceans” but leaves some issues unresolved. He says that there is enough variability in the delta elevations to suggest that there is not just one level coastline, and that it is “hard to explain” why some valleys end at much higher elevations than the proposed ocean. “One possible explanation is a large-scale deformation of the planet, which warped the landscape, transforming what was once a level shoreline into one with more variable elevations,” he says. [Nature News]

Of course an ancient Martian ocean leads to other questions: For one, where did all that water go?

Related content:
80beats: Scientist Smackdown: Did Mars Phoenix Find Liquid Water?
Bad Astronomy: New evidence of (transient) liquid water on Mars!
Bad Astronomy: Unpeeling the history of water on Mars
Bad Astronomy: Are Martian gullies formed by water or not?

Image: NASA, Goddard Space Flight Center, Scientific Visualization Studio/ Greg Shirah

Leon Jenkins is the President of the LA chapter of the NAACP, the organization that advocates for equal rights for black people. The work they do is fine by me, and I support their efforts. But organizations are made up of individuals, and individuals can make mistakes.

This is really one of those times. Here’s the story: Hallmark came out with a card for recent graduates, and it’s one of those deals that has a speaker in it that activates when you open it. Like all such cards it’s twee and sugary and over the top. It involves two cartoon characters with squeaky and high-pitched voices talking about how the graduate can now take over the world. It has an outer space theme to it, and what they say, well… watch/listen for yourself:

Um, yeah. It’s pretty clear to just about anyone who hears it — and doesn’t have any particular stake in the claim — that the card is saying “black holes”. The space theme is obvious enough, and black holes are a common topic. So why on Earth would someone think the card is saying “black whores”, as Mr. Jenkins and other LA NAACP members do?

In fact, there’s a good reason. What we have here is a very well-understood topic to skeptics: audio pareidolia. That is, mishearing recorded phrases or words, and thinking they are saying something else. This phenomenon is really strong, and once you think a recording is saying a certain phrase, it’s difficult to not hear it. So once someone thought the Hallmark card was saying “black hos”, they told other people, and that biased them into hearing it as well. I’ve written about this before; go here and here for great (and very funny) examples of this.

So it’s understandable that Mr. Jenkins might hear that… but then his own biases kick in. He looks at the card and finds pretty dubious evidence to support his claims; like saying that the word “ominous” means “evil” and therefore cannot be used for inanimate objects. In reality, ominous means foreboding or menacing like an omen, so of course it can be used for events or objects. Like many people do when making a claim, Jenkins is finding evidence after the fact that simply isn’t there.

Because honestly, when you think about it: Hallmark? Putting out a card that uses a racial slur? Hallmark’s products are the least offensive, blandest I can think of. They’re the lettuce-and-lite-no-transfat-mayo-on-white-bread sandwich of greeting cards.

But that doesn’t really make much of a difference to someone once their mind is made up. Note that Jenkins also says, “If reasonable people can listen to this and interpret it the way I did, you can pull [the card off the shelves].” That’s wrong, and in fact somewhat dangerous thinking; just because a lot of people think something is true doesn’t make it true.

Still, caving to this pressure, Hallmark pulled the card.

That’s too bad. The company took a financial and PR hit because of the customers’ misunderstanding, and that’s a bad precedent.This just reinforces the overall problem of people making decisions in their lives based on bad evidence or the misinterpretation of good evidence. How many ills of this world would disappear if we could make that go away?

Also, and more importantly, when anyone accuses someone else of racism when it’s not there, it hurts the overall cause. Given the press this has received, it’s the LA NAACP’s credibility that has taken a hit, not Hallmark’s. Crying wolf diminishes the NAACP’s work, and will make it harder for them to fight real racism the next time it pops up.

And that, to me, is uncritical thinking’s biggest danger. Not that people actively believe in things that are wrong — that’s here to stay — but that it masks the truth and prevents people from seeing it.

Tip o’ the mortar board to Fark.

The Food and Drug Administration has a message for the personal genomics revolution: slow down.

Personal DNA tests have been available for years now from companies like 23andMe and Pathway Genomics, and the direct-to-consumer tests have sold briskly even while the companies tried to sort out whether or how their systems would be regulated by the FDA. Then last month, Pathway took the next big step, offering to sell their tests over the counter in the nation’s largest drugstore chain, Walgreens.

For the FDA, that was one step too far, and it began to make noise about regulation. Now the agency’s leader in this field, Alberto Gutierrez, has sent official letters to all the major personal DNA-testing companies saying it intends to regulate the tests as medical devices, and that the companies must provide evidence of their scientific validity.

The letters, posted on the F.D.A. Web site on Friday, say the companies must apply for approval or discuss with the agency why certain test claims do not require such approval. But the letters stop short of saying the tests must be taken off the market until they are approved. Dr. Gutierrez said in an interview that it would be unfair to remove the tests from the market because the agency had not clearly told the companies that the devices needed approval [The New York Times].

Should your access to your own genome really be controlled by the FDA? As we noted when we covered the reasons why it might be a bad idea for Walgreens to carry the tests, it’s the consequences of that information that have the regulators concerned. The personal genomics companies don’t just send you a report with a bunch of A’s, C’s, G’s and T’s: They interpret the data, and sometimes give risk assessments for disease. Gutierrez says the companies must account for that.

Gutierrez said in an interview that if a person can do nothing about a genetic risk discovered through a test, “that at least should be stated somewhere.” He added that companies are also responsible for anticipating possible harm from a test — such as a person adjusting their drug doses on the basis of a result — and should take steps to “mitigate that risk” [Washington Post].

Just how those companies will “mitigate that risk” enough to satisfy the FDA remains unclear. But the risk of people using information that hasn’t been seen by doctors to self-medicate was enough for the FDA to reverse its previous position. Genome.gov, the site of the National Institutes of Health’s National Human Genome Research Institute, states:

The Food and Drug Administration (FDA) regulates tests sold as “diagnostic devices,” that is, tests manufactured by one company and then sold as a kit to a laboratory for genetic testing. However, the FDA does not regulate “home brew” tests, that is, tests that are both manufactured and performed by the same laboratory. Many common genetic tests (including the BRCA breast cancer gene tests) fall into this category. Because of this regulatory exception, genetic testing services using home brew tests can be marketed directly to the medical community — and the public — without FDA regulation or oversight.

Not anymore. These tests qualify for that “home brew” definition, The New York Times says, but the FDA has clearly chosen to jump into the regulation ring.

The companies’ statements sound like they intend to comply. But this new regulatory process could slow the race to get more and more genetic testing into the hands of consumers. Walgreens first said that Pathway Genomics had reassured them the tests it was going to sell didn’t require FDA approval, but then decided to put its plans on hold after the FDA complained and Congress said it might investigate. And 23andMe, one of the highest-profile companies in the group, didn’t do itself any favors this month when it goofed and gave up to 96 customers the wrong genetics reports.

Related Content:
80beats: 5 Reasons Walgreens Selling Personal DNA Tests Might Be a Bad Idea
80beats: Walgreens’ Genetic Tests on Hold, Under Congressional Investigation
DISCOVER: How Much Can You Learn from a Home DNA Test?
Discoblog: Welcome, UC Berkeley Freshmen! Now Hand Over Your DNA Samples
Discoblog: 23andMe To Customers: Oh Wait, Those Are Somebody Else’s Genes

Image: flickr / nosha

We were initially surprised that our co-authored book, Unscientific America, was so strongly attacked for observing that scientists should strive to improve their skills at public communication--and that this probably includes not alienating potential religious allies or mainstream America. But in a sense, the attacks made a kind of sense. Mostly, they came from those for whom this advice ran contrary to their particular project of denouncing much of America and the world for alleged ignorance and superstition--the New Atheists. However, with a recent review in The New Atlantis, it appears that we also touched a nerve on the political right. As this is a more interesting phenomenon, I want to explore it in this post. First, The New Atlantis introduces me as the author of The Republican War on Science, a book whose argument runs directly contrary to the publication's own project of articulating and defending conservative approaches to science, and pinning anti-science sentiment on liberals. So, there's that. It is more surprising, though, to find that the critique (from Ari N. Schuman) echoes the perspective of those traditionalists--apparently over-represented in the science blogosphere--who instinctively distrust calls for improved scientific communication. These critics tend to argue that any hint of message framing ...

The Guggenheim Museum in Manhattan may seem the ultimate arbiter of contemporary art success, with space on its rotunda walls reserved for the world’s buzziest artists. But this October the museum will showcase 25 videos made not by famous or even up-and-coming artists. Instead, the museum is preparing to welcome the unknowns–from YouTube.

The museum and the video site are pairing up on a project they call YouTube Play: A Biennial of Creative Video. Participants can submit videos (one per person) created within the last two years, until the July 31 deadline.

As one might expect from a collaboration with a site that features both dancing birds and baby delivery how-tos, the competition has few entry restrictions. The hope, as described in a promotional video, is to tap the truly “new” and “to reach the widest possible audience, inviting each and every individual with access to the Internet to submit a video for consideration.”

From the countless entries that are sure to come, the museum will whittle the submissions down to 200 of the most promising and then an expert panel will narrow these down to the final 20 to 25 for display. Within that selection there will be no winners or runners-up, the museum says, because the aim is to present a sampling of the most exciting work.

Some might fear giving the high art throne to videos that routinely refashion other creative works, and Nancy Spector, deputy director and chief curator of the Guggenheim Foundation, recognizes such skepticism. She told The New York Times:

“If this is all the Guggenheim did, it would be a problem,” Ms. Spector said. “There are many layers to our programming. And we can’t say at this point that this won’t spawn ongoing relationships with people we discover through this process. One can only hope that it will.”

Related content:
Discoblog: Photo Gallery: When Artists Take Over the Science Fair
Discoblog: When Art Gets Personal: Woman with Skin Disorder Makes Her Body a Canvas
Bad Astronomy: Art + science + NYC = Science Fair
80beats: Tattoo-Removing Lasers Also Remove Grime From Classic Works of Art

Image: flickr / boobooo

You try coming home on time after traveling four billion miles.

Three years after its initially scheduled return date, Japan’s Hayabusa spacecraft returned to Earth yesterday and dropped its collection canister in the Australian outback. The team from JAXA, Japan’s space agency, hopes that the container holds samples from Hayabusa’ 2005 landing on an asteroid called Itokawa. They won’t know for sure for a couple weeks, but Hayabusa has already made history by landing on an asteroid and returning to Earth.

(Check out DISCOVER blogger Phil Plait’s post featuring video footage of Hayabusa’s return in which the probe breaks up into a spectacular flash.)

The headline on JAXA’s website currently reads, “Welcome back HAYABUSA to Earth after overcoming various difficulties!” That’s putting it mildly:

Hayabusa was originally due to return to Earth in 2007 but a series of technical glitches — including a deterioration of its ion engines, broken control wheels, and the malfunctioning of electricity-storing batteries — forced it to miss its window to maneuver into the Earth’s orbit until this year [AP].

And there are no guarantees the craft got any samples. When Hayabusa landed on the asteroid, it was supposed to fire a projectile into the surface. The idea was that this would kick up enough dust for the spacecraft to grab with its collector, but nobody knows whether or not that actually worked. If it didn’t, researchers say there’s still a good chance that Hayabusa brought home asteroid samples:

“It may have worked, it may not; we just don’t know,” said Dr Michael Zolensky from NASA’s Johnson Space Center. “But even if it didn’t work, the spacecraft landed for half an hour on the surface, and during that landing — it was a hard landing — it should have collected a sample even without firing anything. So, we’re pretty confident there’ll be something inside the spacecraft” [BBC News].

The sample container crashed down in an Australian military zone called the Woomera Prohibited Area, where helicopters spotted it after about an hour of looking. Japanese, Australian, and American scientists are preparing the container for its trip to Tokyo. Fingers crossed for the little spacecraft that could: If it did return asteroid dust, it would be the first to do so. (NASA’s Stardust mission has brought comet samples home before, and of course the Apollo Astronauts returned with moon rocks.)

Related Content:
Bad Astronomy: Video of Hayabusa’s Return
80beats: Today in Space: S. Korean Rocket Blows Up, Japan Craft Spreads a Solar Sail
80beats: Japan’s Damaged Asteroid Probe Could Limp Back to Earth in June

Image: JAXA

After the scale of the BP oil spill in the Gulf became evident, Photographer Nathaniel Welch went to Venice, Louisiana, to see what had become of his favorite fishing grounds. He used artificial light to capture these objects as he found them on the beach. Welch: “Ryan Lambert of Cajun Fishing Adventures took me out on his boat to some outer islands near Grande Isle, LA, where the majority of oil was starting to come ashore. As we got close to the island on the backside, we started to see an oil slick in the bay, not thick black oil, just a sheen on the water, too subtle to photograph, but you could smell it. We pulled up on the back of the island, got out, and walked out onto the beach on the front of the island. Big gooey tar balls were on the beach and also coating everything from old beer cans to marsh vegetation. There was an eerie absence of wildlife.

I’ve been going down to Venice, Louisiana for years to fish. I’ve fished offshore for the pelagics like tuna and marlin, and I’ve fished inshore in the marshes for coastal species like trout and redfish. It’s an understatement to say the fishing is exceptional. It is ironic that when fishing offshore there, the oil rigs are the fishing destination and that’s where we would set up. The fish congregate underneath and around the rigs, as the small bait fish use it for protection.”

The U.S. Fish and Wildlife Service reports that there are 35 National Wildlife Refuges that line the coasts of Louisiana, Mississippi, Alabama, and Florida that are currently at risk from the BP oil spill. These refuges are home to dozens of threatened and endangered species, including West Indian manatees, whooping cranes, Mississippi sandhill cranes, wood storks, and four species of sea turtles. “This spill is significant, and in all likelihood will affect fish and wildlife resources in the Gulf—and across the North American Continent—for years, if not decades, to come,” said Fish and Wildlife Service Acting Director Rowan Gould in a recent teleconference.

All images Nathaniel Welch/Redux Pictures

Oil coated aluminum can, Louisiana, 6/5/10

What does a sunset look like when you’re racing through space at 8000 meters per second?

This:

Oh, I could go on and on about the curvature of the Earth, the layers of the atmosphere, the distribution of colors, how the aerosol layer is thin and glows after sunset, and what it must be like to go through 16 sunrises and sunsets every day. But you can get all that information from the NASA website. And really, the enduring nature of this picture is not what it shows, but that it was taken by a human being in space.

This week at the Intersection, in addition to our regular postings we're also going to carry a series of guest posts from Science in the News (SITN), a group of Harvard Ph.D. students whose communication attempts we greatly admire. This is the first post, and merely intended to let SITN introduce itself. One hope is that by featuring the group here, we will inspire the growth of similar organizations at other campuses. So, here they go: Science in the News (SITN) is an organization of PhD students at Harvard University, and our mission is to bring the newest and most relevant science to a general audience. At SITN, we strive to share our enthusiasm for science without over-hyping the promise of new discoveries, and to wade through the technical jargon to make science more accessible. For over a decade, we've been presenting a fall lecture series at Harvard Medical School. The lectures focus on a diversity of current and newsworthy topics, such as stem cell biology and climate change. We also publish a regular online newsletter, the SITN Flash. The Flash is written by graduate students at Harvard and focuses on current scientific discoveries and emerging fields. SITN also hosts “Science by the Pint” in ...

So, you’re pretty good at math, are you?  I was playing with math problems online, and ran across a NASA post called “Space Math”.  This is designed for students.  I thought it was fun, so I’m putting a few up here.  Let’s see who can solve them.  I’ll post the answers in the comments before I post the riddle tomorrow.

Problem 1: Capella is three times larger than Regulus, and Regulus is twice as large as Sirius.  How much larger is Capella than Sirius?

Problem 2: Vega is 3/2 the size of Sirius, and Sirius is 1/12 the size of Polaris.  How much larger is Polaris than Vega?

Problem 3: Deneb is 1/8 the size of VY Canis Majoris, and VY Canis Majoris is 504 times the size of Regulus.  How large is Deneb compared to Regulus?

Problem 4: Aldebaran is 3 times the size of Capella, and Capella is twice the size of Polaris.  How large is Aldebaran compared to Polaris?

Problem 5: Antares is half the size of Mu Cephi.  If Mu Cephi is 28 times the size of Rigel, and Rigel is 50 times as large as Alpha Centauri, how large is Antares compared to Alpha Centauri?

One More: The sun’s diameter is 10 times the diameter of Jupiter.  If Jupiter is 11 times larger than Earth, how much larger than the Earth is the sun?

Okay, get those brains in gear and have fun.  You shouldn’t need your calculator, but we won’t laugh at you if you do.  We’ll just work on those self esteem issues ’cause you’re smarter than what you’re giving yourself credit for.  I got a kick out of these, they remind me of the “what color is the bear” problem.  And everybody thank NASA for always coming up with fun ways for our kids to learn about math and the universe.

Effects of exposure to a mobile phone on sexual behavior in adult male rabbit: an observational study.

“The accumulating effects of exposure to electromagnetic radiation emitted by a conventional mobile phone (MP) on male sexual behaviour have not yet been analyzed. Therefore, we studied these effects in 18 male rabbits that were randomly divided into phone and control groups. Six female teasers were taken successively to the male’s cage and the copulatory behavior was recorded. Serum total testosterone, dopamine and cortisol were evaluated. The animals of the phone group were exposed to MPs (800 MHz) in a standby position for 8 h daily for 12 weeks. At the end of the study, the copulatory behavior and hormonal assays were re-evaluated. Mounts without ejaculation were the main mounts in the phone group and its duration and frequency increased significantly compared with the controls, whereas the reverse was observed in its mounts with ejaculation. Ejaculation frequency dropped significantly, biting/grasping against teasers increased notably and mounting latency in accumulated means from the first to the fourth teasers were noted in the phone group. The hormonal assays did not show any significant differences between the study groups. Therefore, the pulsed radiofrequency emitted by a conventional MP, which was kept on a standby position, could affect the sexual behavior in the rabbit.”

Photo: flickr/Climbing Rocks

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I’ve moved on to the final round for the 2010 prize in science from 3 Quarks Daily. Now it’s in the hands of Richard Dawkins. Congratulations to everyone who has made it this far (including my fellow Discover bloggers Sean Carroll and Ed Yong). Stay tuned for the decision on June 21.

80beats aims to bring you all the science news that’s fit to turn into bytes of digital information, but sometimes DISCOVER’s other bloggers get to the juicy news stories first. To make sure you don’t miss anything, here are a couple of links:

• Supersenses! Ed Yong at Not Exactly Rocket Science covers two journal articles in which scientists investigated the amazing sense of touch in seal whiskers and sharks’ equally astounding sense of smell in the water. To test the sensitivity of seal whiskers, researchers blindfolded a seal and had him “read” the turbulence of a wake.

• For the first time, scientists get to watch as an exoplanet orbits its star—63 light years away. Check out Phil Plait’s Bad Astronomy post for the must-see image. Elsewhere on the Web, National Geographic notes that this planet, Beta Pictoris b, is just a baby. According to the paper published in Science, Beta Pictoris appears to be only a few million years old, yet it’s fully formed–which surprised astronomers who thought that planets take much longer to come into their own.

• Finally, a look back to the marine reptiles that ruled the prehistoric seas. A new study suggests that unlike most reptiles, these mighty sea monsters may have been able to regulate their body temperatures, reports Ed Yong. That ability could have allowed these top-of-the-food-chain hunters to swim fast and dive deep, regardless of ocean temperatures.

Who doesn’t miss the excitement, the curiosity, the baking soda volcanoes of the typical grade-school science fair? Even the cutting-edge artists behind NYC’s Flux Factory got a little nostalgic recently, and decided to host a science fair of their own–but the displays are decidedly atypical, and there’s nary a volcano in sight. Try quantum physics and robots instead.

The science fair art exhibit was inspired by “the similarity between the creative and scientific process,” according to the organizers. And did we mention the trophies? Shiny awards were handed out to artists at an award ceremony last night for the best projects in such categories as “Big Violence,” “Most Empirically Rebellious,” and “Most Metaphysically Pursued.”

Science Fair runs through this weekend, so head over to Queens to check it out. Or you can click through this gallery for a selection of our favorite projects.

Dr. Isis and I recently had similar reactions to John Tierney's NYTime's piece Daring to Discuss Women's Potential in Science. What's so "daring" John? It's been discussed. Over and over and over and back again. I was as bored as Isis, until I reached his uh, "daring" question:
I'm all in favor of women fulfilling their potential in science, but I feel compelled, at the risk of being shipped off to one of these workshops, to ask a couple of questions: 1) Would it be safe during the "interactive discussions" for someone to mention the new evidence supporting Dr. Summers's controversial hypothesis about differences in the sexes' aptitude for math and science? And then I was just frustrated. I mean really, do we have to continue to "debate" this? Sure it sparks a lively comment thread, but I'm tired of it. Furthermore there are so many aspects of gender disparity Tierney fails to mention that have a role in academic performance. So I wasn't impressed and decided not to re-write the same post I've composed countless times in the past. Fortunately, the domestic and laboratory goddess did have the stomach to respond, so go take a look...