science in a can

"The unsolved mysteries of the rainforest are formless and seductive. They are like unnamed islands..."

Mon, 20 May 2013 20:05:37 +0930

“The unsolved mysteries of the rainforest are formless and seductive. They are like unnamed islands hidden in the blank spaces of old maps, like dark shapes glimpsed descending the far wall of a reef into an abyss. They draw us forward and stir strange apprehensions. The unknown and prodigious are drugs to the scientific imagination, stirring insatiable hunger with a single taste. In our heart, we hope we will never discover everything. We pray that there will always be a world like this one at whose edge I sat in darkness. The rainforest and its richness is one of the last repositories on Earth of that timeless dream.”

- E.O. Wilson

I'm quite fond of referring to planck lengths as Universe pixels. Because that's essentially what they are! :)

Mon, 13 May 2013 19:29:40 +0930

This idea delights me.

White dwarfs polluted with planetary debris The Hubble Space...

Mon, 13 May 2013 09:21:03 +0930

White dwarfs polluted with planetary debris

The Hubble Space Telescope has found chemical evidence for the building blocks for rocky planets in an extremely unusual place: the atmospheres of two burned-out stars. Called white dwarfs, these stars are small, dim shadows of stars that would have once been like our sun, and they reside 150 light-years from Earth in the young star cluster of Hyades. Hubble’s spectroscopic observations identified silicon and low levels of carbon, both of which are strong indicators of a rocky material similar to that which makes up Earth. “When these stars were born, they built planets,” said Jay Farihi, lead author of the study, “and there’s a good chance they currently retain some of them… Based on the silicon-to-carbon ratio in our study, we can actually say that this material is basically Earth-like.” The material is thought to have ended up in the atmosphere of these stars after they collapsed into white dwarfs, and the larger planets in their solar system nudged asteroids into star-grazing orbits. The stars’ gravitational pull tore the asteroids apart, and the pulverised debris fell into a ring around the white dwarfs and were eventually funnelled inwards to pollute the stars themselves. The discovery suggests that rocky planets may commonly assemble around stars, and may help us to understand what will happen to our solar system in five billion years, when our own sun burns out.

Golden Tortoise Beetle Though it looks exceedingly pretty and...

Fri, 10 May 2013 09:15:36 +0930

Golden Tortoise Beetle

Though it looks exceedingly pretty and jewel-like, this little beetle is actually incredibly metal. At just 5 to 8 millimetres long, the Golden Tortoise Beetle (Charidotella sexpunctata) is native to North America, found on plants such as sweet potato and morning glory. But upset one of these little guys and things change very quickly—they are the first known insect species to have the ability to rapidly change colour, not only when agitated but also during copulation (which, according to the very dedicated Edward M. Barrows of Georgetown University, can last anywhere from 15 to 583 minutes). The beetle has been observed to turn a variety of shades, from liquid gold to purplish to greenish gold to brownish to bright red. These colours are produced by an optical illusion: the beetle’s outer cuticle is transparent and it reflects light through a layer of liquid, and the beetles can alter the reflectivity of this liquid by using microscopic valves controlling moisture levels under their shell. Such reversible colour change is extremely rare, especially since the change is controlled: it’s elicited in response to specific events in their environment, whether it’s finding a mate or being annoyed by curious humans. Researchers speculate that it serves some interesting purposes, from defence (perhaps by mimicking ladybugs, which aren’t as tasty to their predators) to sexual signalling to mates. Be warned, though: if you catch one of these beetles, it will quickly turn a dark, dull brown, losing all the brilliant gold it had in life. To finish on an incredibly hardcore note: as larvae, the beetle has a fork-like structure hinged to its rear end, and will stick old skin and their own faeces to it, creating a shield for defence—otherwise known as a faecal parasol. Told you these little guys were metal.

(Image Credit: 1, 2, 3)

The Quantum of Time If I ask you for the smallest unit of time...

Thu, 09 May 2013 10:20:31 +0930

The Quantum of Time

If I ask you for the smallest unit of time you can possibly think of, you might suggest a second, or a millisecond, or a nanosecond if you’re clever. But while these units are small enough to measure everyday events, physicists have to deal with cosmological forces and events on incredibly tiny scales, so they need to use appropriately tiny units to measure them. In 1899, German physicist Max Planck (who was also, incidentally, the founder of quantum theory) proposed a system of natural units of measurement called Planck units, stated in terms of five universal physical constants: the Gravitational constant, the Reduced Planck constant, the speed of light in a vacuum, the Coulomb constant, and Boltzmann’s constant. The system is based on the idea that space and time aren’t continuous—they’re quantised, which means that there’s a shortest possible measurable length (called Planck length) and a shortest possible measurable time (called, surprise, Planck time). Planck length is roughly 1.616 × 10^-35 metres, and Planck time is the amount of time it takes for a photon to travel a single Planck length, i.e. 5.391 × 10⁻⁴⁴ seconds. This is an unimaginably small quantity, but it helps to define the unimaginable small scale at which current physical theories break down—and helps physicists to study the beginning of the Universe, where the sequence of events in its early evolution was crammed into minute fractions of time.

The Eskimo Nebula In 1787, pioneering astronomer William...

Wed, 08 May 2013 10:20:50 +0930

The Eskimo Nebula

In 1787, pioneering astronomer William Herschel discovered the nebula NGC 2392, nicknamed the Eskimo Nebula because from the ground, it resembles a person’s head surrounded by a fur-lined hood. The nebula lies about 2,870 light years away in the constellation of Gemini, and just 10,000 years ago, its gases composed the outer layers of a star like our sun—but the dying star swelled to the size of Earth’s orbit and its outer layers flung into space in a final burst of glory, forming a planetary nebular. The star became a white dwarf, illuminating the gases around it. Herschel was actually the one who coined the term ‘planetary nebula’, using it to refer to round, ball-like nebulas that reminded him of Uranus, but it’s misleading because while their elements may one day be recycled back into planets, these stellar remnants otherwise don’t have much to do with planets—and yet, the term has stuck. The image above was taken by the Hubble Space Telescope in 2000, and shows far more of the nebula’s complex structure than Herschel could have ever seen: the bright central disc shows a bubble of material being blasted out by solar winds from the nebula’s core, so intense that they’re travelling over 1.5 million km/hr, and the outer disk contains a ring of strange orange filaments that stretch out like comets, yet are light years long. Astronomers are still puzzled about their origin, but suggest the filaments may have been formed by the collision of slow and fast moving gases.

(Image Credit: NASA/Andrew Fruchter)

Apparently I’m now an editor for the #Science tag! So that’s a cool thing to happen.

Thu, 25 Apr 2013 10:31:46 +0930

Apparently I’m now an editor for the #Science tag! So that’s a cool thing to happen.

GUYS GUESS WHAT I went to DC on the weekend and visited the Natural History museum and both Air and...

Wed, 24 Apr 2013 04:32:00 +0930

GUYS GUESS WHAT

I went to DC on the weekend and visited the Natural History museum and both Air and Space museums

and I saw shows in both the planetarium and the IMAX theatre and they were AMAZING

and I also saw rad things like Anita, the spider carried on Skylab for experiments in the 70s, and the Gemini 7 spacecraft, and equipment and spacesuits that had actually been on the Moon

AND I WAS NOT EVEN TEN FEET AWAY FROM THE SPACE SHUTTLE DISCOVERY

Ginkgo Trees Stand Test of Time “Living fossil” is an informal...

Fri, 19 Apr 2013 11:00:29 +0930

Ginkgo Trees Stand Test of Time

“Living fossil” is an informal term used by biologists to describe species that lack living relatives. While you might not personally think being called a fossil is a compliment, these organisms are actually quite impressive survivors. The Ginkgo biloba tree, for example, is strange and unique amongst contemporary plants but incredibly similar to fossils dating back to the Permian, almost 270 million years! This means that even though every single other lineage of the Ginkgo’s relatives changed and adapted beyond recognition or died out, there are still Ginkgo trees growing today that would be indistinguishable from trees from hundreds of millions of years ago. If that fails to impress you, consider this: in Hiroshima, Japan there are still a handful of Ginkgo trees that survived the dropping of the atom bomb in 1945 living to the present day! If these hardy trees can withstand a disturbance of an A-bomb’s magnitude, it is no wonder they have managed to remain viable when so many other ancient plants could not.

Guest post written by Reggie Henke

Hox Genes Hox genes are a type of “general purpose gene” that...

Thu, 18 Apr 2013 11:00:46 +0930

Hox Genes

Hox genes are a type of “general purpose gene” that control the selection and placement of certain building elements in complicated organisms. For example, rat’s have a hox gene that controls whether a tail is “built” or not. In the rat’s case, this gene is turned on so there is a tail on the rat. While at first this may seem like useless information, once hox genes are put into an evolutionary perspective they become much more interesting. For example, chickens have a hox gene for teeth, but this gene is turned off. If this gene were to be turned on, and the beak gene were turned off, a chicken could theoretically have teeth. This is possible because the chicken’s DNA still contains the instructions for “building” teeth that its dinosaur ancestors once had. In this sense, hox genes can be helpful in explaining large leaps of evolutionary development, which before seemed impossible to occur so rapidly in such small amounts of time. But why does the hox gene exist? Hox genes are found because they control homologous to other organisms. In other words, many organisms of very different types and ancestries still have the same hox genes. Another example of hox genes in action is allometric growth. Allometric growth is a change in the rate of growth in a certain feature or dimension in comparison to the rest of the body. For example, some of the evolutionary changes responsible for bat wings are due to allometric growth. Since bat wings evolved out of ordinary paws, either the finger bones increased growth rate along with the skin connecting the bones, or the rate of body growth decreased while the paw rate remained constant. Both theories are examples of allometry.

(Sources: Berkeley/Nature)

Guest post written by slarsen88

Liquid marbles – drops that don’t splash In 2001 two French...

Wed, 17 Apr 2013 11:00:43 +0930

Liquid marbles – drops that don’t splash

In 2001 two French scientists, Pascale Aussillous and David Quéré, discovered that coating a water drop with lycopodium powder gives it strange properties. The coated drop rolls and bounces over surfaces without losing any liquid. They called these weird drops “liquid marbles”. The particles in lycopodium powder are “hydrophobic”, meaning they are poorly wet by water. They sit so far out from the water, that they form a barrier between the water and the outside world. Liquid marbles are bizarre materials. They roll like glass beads due to their hard particle shells. Their shape changes as they bounce, however, due to their soft liquid cores. The presence of the particle shell lowers the temperature at which the liquid inside freezes. They do not have to be made from water and hydrophobic powder. At the Ian Wark Research Institute, Rossen Sedev and I investigated liquid marble formation from a range of aqueous and organic liquids. Our research showed how the particle wettability (the extent to which a liquid wets the particles) determines what happens when a liquid drop is mixed with powder. Our findings help people designing liquid marbles choose the best combination of powder and liquid. You can read more about liquid marbles at the Nature’s Raincoats website and in our publication in the journal Soft Matter.

Image Credits:

1. © Advanced Polymer Materials Lab. Osaka Institute of Technology, 2011

2. © Nature’s Raincoats 2009.

Guest article written by Catherine P. Whitby

The 2 Streams Hypothesis of Vision Most popularized by Milner...

Wed, 17 Apr 2013 07:01:00 +0930

The 2 Streams Hypothesis of Vision

Most popularized by Milner and Goodale in 1992, this hypothesis presents the argument that human neural processing of visual information splits into two distinct streams after reaching the primary visual cortex. Though the model faces criticism for overemphasizing the independence of these pathways— it is more likely that there is interaction between them—, it provides a solid framework for explaining optical phenomena such as the jitteriness of the object borders seen in the illusion above, which feature equiluminant colors (they would be the same shade if you changed the image to grayscale). Considerable evidence gives credence to this model wherein the ventral stream (referred to as the “what” stream) primarily guides object recognition, is better at coding complex visual details, sees in color, has lower contrast sensitivity, and is characterized by slower response time. In contrast, the dorsal stream (“where”) is evolutionarily older, codes for motion and space, is more sensitive to contrast, has shorter response times, but sacrifices resolution. This disparity can be explained by the fact that the two streams are fed by distinct inputs from different populations of retinal cells, which specialize in coding different visual information. The border where the turquoise meets equiluminant red seems to pulsate because the object is seen by the “what” stream, which is fed by retinal cells that take in color information, but not— or not as well— by the “where” stream, since the latter pathway is fed colorblind inputs. Also complicating the perception of the border is the fact that the “where” system’s sensitivity to contrast and quicker neuronal responses causes the brain to constantly re-evaluate the figure-ground relationship. So, moment by moment, your brain changes its mind about which color is darker than the other, and the image seems to pulsate in response to these quick recalculations.

Guest post written by Rachel

Knowmia - Technology for Teaching. Made Simple.

Wed, 17 Apr 2013 06:44:26 +0930

Knowmia - Technology for Teaching. Made Simple.:

I’ve just added Knowmia to my links page—it’s a pretty cool site with lots of collected videos about all kinds of subjects, from algebra to learning Mandarin. Check it out if you want to learn about something new or need help with school work.

The Eastern Newt The Eastern Newt (Notophthalmus viridescens),...

Tue, 16 Apr 2013 11:05:09 +0930

The Eastern Newt

The Eastern Newt (Notophthalmus viridescens), a member of the family Salamandridae, lives in deciduous and coniferous forests throughout the eastern United States and adjacent parts of Canada. They have a unique life cycle: They begin life in an aquatic larval stage, develop into the familiar terrestrial form known as a “red eft,” then return to the water as adults. The red eft stage, shown in the top picture, lasts for 2-7 years and makes up about half of the life span. During this time, the newt is nocturnal and may be found wandering through leaf litter on a rainy night snacking on small invertebrates. (In fact, they are thought to play an important role controlling the populations of small insects like mosquitoes.) When they develop into adults and resume life underwater, they lose the bright reddish-orange coloration and turn yellow/olive, though their bright red spots remain. Although the number of Eastern Newts has declined due to habitat degradation, they are still so abundant in their range that they are not considered to be threatened. Although they don’t seem to mind being picked up, it’s best to keep handling to a minimum and wash your hands afterward because—as bright coloration often indicates—they secrete toxins from their skin when threatened. This is a defense mechanism that makes them unpalatable to predators like birds, mammals, and fish.

(Sources: 1, 2. Image Credit: 1, 2)

Guest Post written by Michaela Alden (skeptic-tank.tumblr.com)

Carbon Planets There are two elements in our universe which are...

Mon, 15 Apr 2013 11:00:29 +0930

Carbon Planets

There are two elements in our universe which are both overwhelmingly abundant, and can be used to make an awful lot of different things: carbon and oxygen. Earth and the rest of the solar system happened to form from an oxygen-rich part of space. Earth’s crust contains a huge amount of oxygen, in rock. All Earth rocks are made of silicate, a chemical compound of silicon and oxygen. So are there any planets which are rich in carbon instead of oxygen? Actually, yes there are, and we’ve already found two! One is PSR J1719-1438, a planet orbiting a neutron star, bathed in x ray sunlight. The other is 55 Cancri e, a super-Earth orbiting a Sun-like star. Carbon planets are likely to be chemically very different from Earth. Their cores would be made from naturally alloyed steel, and they would likely have entire mountain ranges made of diamond.

Guest post written by Invader Xan, who also writes at supernovacondensate.net

Psychological Basis for the Color of Love Red has long been...

Sun, 14 Apr 2013 11:00:32 +0930

Psychological Basis for the Color of Love

Red has long been associated with love around the world, and in studies conducted in 2008 and 2010, psychologists at the University of Rochester — including Daniela Niesta Kayser, pictured above — gave the color scientific backing when they showed that both men and women find the color red more sexually appealing than other colors. One type of experiment showed the subject a black-and-white photo of a person, framed in various colors; another varied the shirt color of the person in the photo. (The photos were digitally manipulated to ensure consistency, and the colors were precisely matched in saturation and brightness levels, differing only in hue.) Subjects were then asked to rate the person in the photo based on different characteristics. Consistently, photo subjects framed in red or wearing red were rated as significantly more attractive and sexually desirable than those framed in or wearing other colors. The results from one experiment in the 2008 study showed that men expressed a willingness to spend more money while on a date if the woman was wearing red. However, the presence/absence of red did not change how men or women rated the subject of the photo in terms of likability, intelligence, or kindness. In addition, the studies showed that red had an effect on a straight man or woman only when shown a person of the opposite gender. The presence/absence of red didn’t affect how straight men and women rated the attractiveness of someone of the same gender. But what about men and women who don’t identify as straight? Perhaps further research will explore how red affects members of the LGBT community when rating people of the same and opposite genders.

(Image Credit: University of Rochester)

Guest Post written by lizhasthoughts

Everybody Claps From French opera to Amazonian tribe dances,...

Sat, 13 Apr 2013 09:01:05 +0930

Everybody Claps

From French opera to Amazonian tribe dances, performances will be rewarded with the noise of humans smacking their hands together in sync. Applause is a behaviour as widespread as humanity, but how has it become so ubiquitous? We know that clapping mimics the behaviour of apes in excited states – stamping, whooping and slapping are orang-utan reactions to food or friends. But primates don’t truly applaud unless they’re taught to. Lift your hands and clap them together. Think about what a complex action it is: cupping your hands so you burst the air pocket between your palms, having the energy to repeat the action, knowing what speed matches the people around you. So why this, over howling or kicking or stamping? Some theorists link applause solely to the group effect, citing the tendency of applause to synchronise — listen to the next slow clap you hear, and marvel at our ability to keep steady time. Clapping also tends to be prompted by a group experience, like a punchline or a spectacle. Research at York University shows that just as people laugh louder in company to prove they’ve gotten a joke, applause is more synchronous in response to a snappy turn of phrase. It makes us feel included, a part of the group, and so has an evolutionary basis. Others suggest that clapping is instinctive. Babies clap in happiness from the age of four months, and patients in catatonic states will often adopt clapping as a fixation, suggesting that it produces pleasure independent of company. This could be because of the soothing regularity and rhythm it produces. But further, there is evidence that the act can induce seizure-like brain activity, pleasurable in short bursts. In which case, clapping is not just learned, but hard-wired in our brains.

Guest article written by biocurious

Badass Scientist of the Week: Caroline Herschel Caroline...

Fri, 12 Apr 2013 09:00:52 +0930

Badass Scientist of the Week: Caroline Herschel

Caroline Herschel (1750-1848) grew up in Germany, as the daughter of a professional musician. Her father gave all his children a broad basic education in art, music, and science. His wife did not approve of educating her daughter, and when her father died, Caroline’s mother put her to work in the kitchen. Caroline had had several childhood diseases that had left her slightly disfigured, and her mother didn’t think she’d be good enough to marry, so she settled on a life of housework for her daughter. Meanwhile, one of Caroline’s older brothers, William Herschel, had moved to England, where he was working as a composer and music director, and built telescopes in his spare time. When he found out that his mother had put his sister to work as a servant, he invited Caroline to move in with him in England. She did, and quickly got a successful career as a singer. While Caroline stayed with William, he made a discovery that would change both of their lives. Using a telescope he built himself, William Herschel discovered the planet Uranus in 1781. He was hired by King George III as “King’s Astronomer”, and quit his music career to devote all his time to science. Caroline helped him out, first by cleaning lenses and taking notes, but later with astronomical observations of her own. She discovered a number of comets, including one that was named after her, and as reward for her work, the state paid Caroline a regular stipend, making her the very first woman to receive a salary for scientific work.

Guest article written by Eva, who writes about scientists/musicians on easternblot.net and on Tumblr as MusiSci

Ancient Megaflood on Mars For a long time, scientists believed...

Sun, 07 Apr 2013 10:20:34 +0930

Ancient Megaflood on Mars

For a long time, scientists believed that Mars has been cold, dry, and geologically inactive for three billion years, its water locked in polar ice caps—but over the past decade or so, a new picture of the planet has started to emerge. Radar from NASA’s Mars Reconnaissance Orbiter (MRO) has recently given us evidence that channels criss-crossed the planet and flooded it long ago. Scientists have known about a nearly 1000-kilometre channel system called Marte Vallis for a while, but it’s been difficult to see because it’s located beneath the surface. Marte Vallis is a valley in the equatorial region of Elysium Planitia, the youngest volcanic region on the planet. Volcanism in the last few hundred million years covered its surface with lava, obscuring evidence of the Marte Vallis channel system—but 3D images from the MRO have revealed the major underground channels. They’re twice as deep as originally thought, and were created by an ancient, catastrophic megaflood—the power of the water dug deep channels in the hardened lava. “This is the first time we’ve been able to see buried flood channels on a planet other than the Earth,” says the lead study author, Gareth Morgan of the Smithsonian Institution’s Air and Space Museum. “The source of the floodwaters suggests they originated from a deep groundwater reservoir and may have been released by local tectonic or volcanic activity.” The largest of the channels was carved within the past 500 million years—surprisingly recent in geological terms, meaning Mars is not dead, but still dynamic. Probing the mysteries of Marte Vallis could offer insight into a period that was once thought to be barren and dry, and could tell us how water shaped the Mars’ history—including the climate change events that led to the planet becoming what it is today.

(Image Credit: UniverseToday/NASA)

SO, UH, THIS HAPPENED. I’m literally stunned by how many...

Sat, 06 Apr 2013 11:40:43 +1030

SO, UH, THIS HAPPENED.

I’m literally stunned by how many people want to learn science from me. For all the newbies, I’m Lauren, the lone writer of this occasionally absurd blog, and you can read more about me here if you’re curious. sciencesoup hasn’t even reached its first birthday yet, but I’m going to wield this power for good and teach every single one of you some ridiculously amazing things about the universe!