Science News

Headlines

. The heaviest element is officially named
. Were dinosaurs poisonous?
. 'Perfect' liquid hot enough to be quark soup
. Flower family knows its roots
. Making light of sleep

The heaviest element is officially named
Everything on Earth that scientists can see, measure or study is made of atoms -- and atoms are named by what type of element they are. You probably know the name of many elements, such as oxygen, gold or hydrogen. Others, such as cadmium or xenon, may sound strange and exotic. In any case, elements are everywhere: You, your shoes, your desk, cars, water, air -- all are made of elements.
Now, there's a new element: copernicum.
This element was officially named on February 19, but the element itself isn't new. German scientists made and observed it in 1996. But in the 14 years since then, other scientists have been working to study and validate the original findings. A scientific breakthrough is validated when other scientists can perform the same experiment and get the same results. Validation is an important part of the scientific process because it demonstrates that a scientific discovery was not a mistake.
All that hard work finally paid off when the element finally received its name, copernicum, from the International Union of Pure and Applied Chemistry (the organization in charge of making sure chemists all over the world use the same words to mean the same things.) Copernicum is named in honor of Nicolaus Copernicus, a 16th century Polish scholar who proposed that Earth orbits the sun (rather than that everything orbits Earth) and that Earth turns on its own axis. These ideas may seem obvious now, but in 16th century Europe, they were revolutionary.
The element copernicum has 112 protons and is named for the 16th century scholar Nicolaus Copernicus.
Scientists organize all the elements on a chart called the Periodic Table. Each element gets a symbol and its own number, and copernicum gets the symbol Cn and the number 112. This number means that inside every atom of copernicum are 112 protons. Protons are particles inside the nucleus, or core, of every atom. The lightest element, hydrogen, has only one proton inside each atom.
Its 112 protons make copernicum the heaviest known element with a name. It was first observed by Sigurd Hofmann, a scientist at the Center for Heavy Ion Research, or GSI, in Darmstadt, Germany. Hofmann and his team created copernicum in the laboratory when they blasted atoms of lead (each with 82 protons) with zinc isotopes, kinds of zinc atoms that each had 30 protons.
This was no easy process: You can't just shoot one atom at another and expect the atoms to buddy up. In 1996, Hofmann and his team had to figure out a way to get all the protons together -- and stick. They used a machine, called the Universal Linear Accelerator, that can accelerate atoms up to 10 percent the speed of light. After a week of working on these high-speed collisions, Hofmann's team found copernicum -- even though it quickly vanished. Most of the superheavy elements in copernicum's neighborhood -- those that are heavier than uranium -- tend to be unstable, which means they decay into smaller atoms quickly.
Now, 14 years after Hofmann's experiment, other scientists are able to make copernicum and validate Hofmann's original work. Scientists are excited about copernicum. If such a superheavy atom can be created, then even heavier elements might be waiting in the future.
Were dinosaurs poisonous?
In 2009, a team of scientists examined a well-preserved skull of a dinosaur called Sinornithosaurus which lived about 125 million years ago. They noted several features suggesting it was probably poisonous. It is the first-identified venomous dinosaur. They noted that the unusually long and fang-like mid-jaw (maxillary) teeth had prominent grooves running down the outer surface, towards the rear of the tooth. This is a feature seen only in venomous animals. The poison was probably produced in glands housed in the triangle-shaped depressions on the creature's upper jaw.
These unique features indicated that Sinornithosaurus may have specialized in hunting small prey such as birds, using its long fangs to penetrate feathers and envenomate and stun the prey, like a modern snake. The short, slightly forward-pointing teeth at the tip of the jaw could have been used to strip feathers from birds.
Flower family knows its roots
Jewelweeds, or Impatiens, are pretty flowers that grow in wet, shady spots all over the Northern Hemisphere. According to a recent experiment, they seem to know their own flower family.
The experiment suggests that these flowers can recognize each other--or at least, recognize whether or not they came from the same mother plant. Together with other experiments, these results show that if the plants are recognizing their kin, it's not through their leaves, it's through the roots.
In an experiment, jewelweeds were planted in pots with either siblings or strangers. Sibling plants were grown from seeds that came from the same mother plant. Stranger plants were grown from seeds from different plants.
Impatiens normally grow in the shade, where sunlight is scarce. When jewelweeds were planted in pots with strangers, the plants started to grow more leaves than if they had been planted alone. This response suggests that plants are competing with strangers for sunlight, since a plant with more leaves can receive more light--and make more food.
However, the plants reacted only mildly when they were planted next to siblings: they grew a few more branches than they normally would if they were alone -- but they did not start growing lots of extra leaves. This behavior suggests these plants are more likely to share resources, rather than compete.
The plants only responded this way when they shared soil. If stranger seedlings were planted in different pots and placed next to each other, for example, they did not grow more leaves. This difference suggests that the plants must be using their roots to detect sibling plants in the same soil.
'Perfect' Liquid Hot Enough to be Quark Soup
The Relativistic Heavy Ion Collider (RHIC) is an atom smasher at the Brookhaven National Laboratory where heavy atoms are collided into one another at great energies. Researchers have established that collisions of gold ions traveling at nearly the speed of light have created matter at a temperature of about 4 trillion degrees Celsius -- the hottest temperature ever reached in a laboratory. This is about 250,000 times hotter than the center of the Sun.
This temperature, based upon measurements by the PHENIX collaboration at RHIC, is higher than the temperature needed to melt protons and neutrons into a plasma of quarks and gluons. Quarks and gluons are the particles that make up the protons and neutrons. It is as though the energy of the collision allowed the proton to break up, spewing out all its innards. 
These new temperature measurements, combined with other observations analyzed over nine years of operations by RHIC, indicate that RHIC's gold-gold collisions produce a freely flowing liquid composed of quarks and gluons whose constituent particles interact very strongly among themselves. This liquid matter has been described as nearly perfect in the sense that it flows with almost no frictional resistance, or viscosity.
Such a substance, often referred to as quark-gluon plasma, or QGP, filled the universe a few microseconds after it came into existence 13.7 billion years ago.
The research program at RHIC will be complemented by studies soon to get underway at the Large Hadron Collider (LHC), a 27-mile-circumference particle accelerator beginning operations in Europe.
Making light of sleep
Maybe this has happened to you: In the middle of class, while you pretended to be paying attention to the teacher's lecture, your eyelids started to droop.
Don't be too hard on yourself. That late night movie may not be to blame. The problem may be with your clock. Not the clock on your nightstand, but the one in your head. All mammals have a clock located inside their brains. Similar to your bedside alarm clock, your internal clock runs on a 24-hour cycle. This cycle, called a circadian rhythm, helps regulate when you wake, when you eat and when you sleep.
Somewhere around puberty, something happens in the timing of the biological clock. The clock pushes forward, so adolescents and teens are unable to fall asleep as early as they used to. When your mother tells you it's time for bed, your body may be pushing you to stay up for several hours more. And the light coming from your computer screen or TV could be pushing you to stay up even later.
This shift is natural for teens. But staying up very late and sleeping late can get your body's clock out of sync with the cycle of light and dark. It can also make it hard to get out of bed in the morning and may bring other problems, too. Teenagers are put in a kind of a gray cloud when they don't get enough sleep: it affects their mood and their ability to think and learn.
But just like your alarm clock, your internal clock can be reset. In fact, it automatically resets itself every day. How? By using the light it gets through your eyes.
Scientists have known for a long time that the light of day and the dark of night play important roles in setting our internal clocks. Recent discoveries show that the human eye has two separate light-sensing systems. One system allows us to see. The second system tells our body whether it's day or night.
Light is detected by the eye's retina. The retina contains millions of light-sensitive cells called photoreceptors. Two important types of photoreceptors are rods and cones. When they detect light, rods and cones pass the visual signal from nerve cell to nerve cell to the visual processing part of the brain. There, the signals are analyzed to tell you what you're looking at.
A few years ago, scientists discovered another type of light-sensitive cell in the eye. These cells are called melanopsin ganglion cells. Like rods and cones, these ganglion cells are found in the retina. But unlike rods and cones, melanopsin ganglion cells send their signals to the part of the brain that regulates the body's master clock.
The light signals sent to your body's master clock tell you when to be sleepy and when to be alert. But not just any light will do. The circadian clock can distinguish between different colors, or wavelengths, of light. Blue light -- such as the light from the blue sky -- is best for stimulating the circadian system. In experiments, people exposed to blue light become less sleepy and more alert.
This might explain why stepping outside on a bright sunny day helps clear the fog from your head.