The moon (Photo: NASA)

The Earth and its moon started with a big bang, according to a new theory from NASA scientists, who believe both were born out of collisions between two massive developing planets.The new theory suggests the two giant planetary bodies, each about five times the size of Mars, collided with each other twice.

After the first collision, the planets smashed into each other again, leaving behind material which resulted in our early Earth. The fledgling planet was surrounded by a disk of left-over material, which later combined to form the moon.

This new theory challenges the widely-held “giant impact hypothesis,” which suggests the moon formed early in our solar system’s history after an enormous impact between Earth and a Mars-sized planet that was still being formed.  Some call that protoplanet Theia, after the mother of the goddess of the moon in Greek mythology.

However, skeptics say if the Theia theory were true, Earth and the moon would have different chemical compositions from each other, which they don’t.

Iconic photo of the Earth and moon as seen from the Apollo 8 spacecraft while in lunar orbit on 12/24/1968. (Photo: NASA)

According to the new NASA theory, the two collisions, along with the subsequent melding of left-over material, formed both the Earth and the moon, which is why they have similar chemical compositions. “Our understanding of the solar system is constantly being refined with each new discovery,” says NASA’s Greg Schmidt. “This research illustrates the importance of modeling planetary formation to enhance our scientific understanding of the moon and its place in the solar system.”

The model which demonstrates this new theory was developed at the Southwest Research Institute (SwRI), in San Antonio, Texas by Robin M. Canup.

Canup says her work was inspired by previous studies on the early history of the moon, which explain the similar chemical composition of the Earth and moon, while at the same time producing an appropriate mass for Earth and the moon.

“The ultimate likelihood of each impact scenario will need to be assessed by improved models of terrestrial planet formation,” Canup said.  Canup’s work is outlined in Science.

Video: A computer simulation of a low-velocity collision of two protoplanets that contain 45 and 55 percent of the Earth’s mass. Colors indicate particle temperature in kelvin, with blue-to-red indicating temperatures from 2,000 K to in excess of 6,440 K. After the first protoplanetary impact, they re-collide, merge and form a rapidly spinning Earth-mass planet that is surrounded by a disk of particles that would later form the Moon. (Video: Southwest Research Institute)

The land-based hermit crab Coenobita compressus lives inside a discarded snail shell and forages for food along the Pacific coast from Mexico to Peru. (Photo: Mark Laidre, UC Berkeley)

Despite its name, the hermit crab can be a very social creature.  In fact, when searching for a new home, the crustacean gets by with a little help from its friends, according to a new study in Current Biology.

The hermit crab, which is vulnerable to predators, protects itself by making its home in abandoned marine snail shells.

To fit its ever-growing body, the hermit crab will often hollow out and customize their appropriated shells, sometimes doubling its internal size.  But, after a while, the crab is forced to look for a bigger place to live.

There are about 800 species of hermit crabs and most live in the ocean, where empty snail shells are abundant due to the prevalence of predators with an appetite for marine snails. However, competition for shells among land-based crabs can be intense.

California researchers found that once three or more of these crabs congregate, dozens of others eager to find nicer homes also show up.

House hunting, hermit crab style. Whenever three or more of these crustaceans show gather, others are bound to join in. A free-for-all takes then place with all crabs intent on displacing someone else to get into a bigger shell. (Photo: Mark Laidre, UC Berkeley)

The crabs form a sort of conga line, from smallest to largest, each holding onto the crab in front of it.Once the largest of the group finds his dream home, he kicks out its current occupant and moves into the new shell. That frees up his old shell for the crab behind him.

This process continues until the smallest of the group moves into a new space.  As a result, like the children’s game musical chairs, the smallest crab is left without a shell of its own, making it susceptible to any predators in the mood for a little crab dinner.

“The one that gets yanked out of its shell is often left with the smallest shell, which it can’t really protect itself with,” says the study’s author, Mark Laidre, from the University of California, Berkeley. “Then it’s liable to be eaten by anything. For hermit crabs, it’s really their sociality that drives predation.”

Laidre conducted his research along the Pacific shore of Costa Rica, where millions of the hermit crab species,Coenobita compressus, can be found along the tropical beaches.

A marine snail shell newly vacated by its original owner (left) and a shell that has been remodeled and hollowed out by a hermit crab (right). (Photo: Mark Laidre, UC Berkeley)

For his study, Laidre  tethered individual crabs to a post, the largest being about three inches long, and then observed the brouhaha which usually took place within 10 to 15 minutes of the crab being  tethered.

After moving into its new home, the crustacean usually gets to work immediately, remodeling and hollowing out the shell.  Laidre discovered how critical those remodeled shells are to the hermit crab after pulling them from their homes and offering newly vacated snail shells instead. He found that none of those crabs survived.

Apparently, Laidre says, only the smallest hermit crabs are able to take advantage of brand new shells, since only the smallest hermit crabs can actually fit inside shells that haven’t been hollowed.  Even if a crab does find a new shell it can fit in, hermit crabs of all sizes would rather not spend all of the time and energy to hollow it out itself.

The hermit crab’s unusual conduct, according to Laidre, serves as a rare example of how evolving to take advantage of a specialized niche – in this case, the hermit crab living on land versus in the ocean – led to an unexpected byproduct: socialization in what is typically solitary animal.

This small portion of a deep space image taken by the Canada-France-Hawaii Telscope Legacy Survey reveals thousands of galaxies yet to be explored. (Image: © CFHT/Coelum/Terapix/AstrOmatic)

Scientists have released the final version of the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS), data gathered over six years which probes deep recesses of the Universe, including galaxies as far as nine billion light-years away.

This treasure trove of information  will allow scientists to better study dark matter; energy;  new, developing and evolving galaxies; and any solar system bodies beyond the orbit of Neptune, in a region called the Kuiper Belt.

The unique and powerful multi-color collection of astronomical images and data put together by the international team,  was gathered from the Canada-France-Hawaii Telescope (CFHT) located atop the summit of Hawaii’s Mauna Kea volcano.

The project is led by French and Canadian astronomers who imaged and mapped an extremely large volume of the Universe using a ground-based, rather than space telescope, such as the Hubble.

The dome of the Canada-France-Hawaii Telescope (CFHT) is a world class 3.6-meter telescope that sits above the clouds atop Hawaii’s Mauna Kea, a dormant volcano. (Photo: © J.-C. Cuillandre (CFHT))

“The Legacy Survey has already generated a lot of results and is the most heavily cited work from CFHT,” says Raymond Carlberg of the University of Toronto, who helped with project planning and oversight.

The high-quality images  allowed them to produce a large data bank which includes dark matter maps on the largest scale  ever  observed, according to the researchers.

The data set also contains the first high-quality light measurements which show that dark energy closely resembles the cosmological constant,  which counteracts the gravitational pull of matter, something  Albert Einstein predicted in his General Theory of Relativity and  later thought might have been his greatest mistake.

Although dark matter and dark energy dominate the universe,  they can’t be seen or identified.  However, astronomers are able to measure the effect that dark energy has on the rate of the expansion of our universe.

To help scientists gain a better understanding of dark energy, the Legacy Survey team set out to precisely measure several hundred “Type Ia” supernovae, which they say are excellent standard light measurements for measuring galaxy distances.

At the heart of the Legacy Survey was a state-of-the-art, 340-Megapixel digital camera called MegaCam, that was coupled to the 3.6-meter Canada-France-Hawaii telescope in Hawaii.  More than 15,000 individual MegaCam images were used to produce the survey.

This is image filled with a number of galaxies and other cosmological objects was taken from just a very small fraction of the Canada-France-Hawaii Telescope Legacy Survey (Image: ©CFHT/Coelum)

Observations began in 2003 and ended in 2009.  The scientists then took three more years to precisely calibrate the huge volume of data gathered from the images.

In the course of their work, project members were able to image and map across a combined area of the heavens which is about 800 times the surface area of the full moon as seen in the sky.

The survey revealed some 38 million celestial objects, which were mostly  distant galaxies in various stages of evolution.

The search for new solar system bodies beyond Neptune’s orbit, in a region called the Kuiper Belt, also proved successful. That area of space contains numerous chunks of material left over from when the solar system formed.

The astronomers  were able to collect what they term “an exceptional sample” of minor bodies in that region.

A new initiative, the Canada-France Ecliptic Plane Survey, has taken over that area of study. With Legacy Survey data, as well from other telescopes, those scientists have so far been able to determine the orbits of nearly 200 Kuiper Belt objects with high-precision. Other astronomers studying the formation of our solar system are also using the Legacy Survey’s information to test various scientific models.

“The legacy  will not be limited to follow-ups of the survey,” says Yannick Mellier, who leads a group of scientists  contributing to the European Space Agency’s Euclid mission – a space telescope with cameras designed to accurately measure dark energy. “MegaCam and the CFHTLS truly paved the way for the Euclid space mission both from the scientific and technical aspects.”

As shown in the above video, the supernova reaches its peak very quickly (a few days) and then slowly fades out over weeks to months. At its peak, a supernova can shine brighter than all the other stars combined in the host galaxy. The animation spans about 4 months, from pre- to post-supernova status. Credit: SNLS

Illustration of the interior of ’55 Cancri e’ — an extremely hot planet with a surface of mostly graphite surrounding a thick layer of diamond, with a molten iron core at the center. (Image: Haven Giguere)

Scientists have found a planet outside of our solar system which could be a true diamond in the rough.

This gem of a planet is twice Earth’s size, according to the US-Franco team that found it, and its surface appears to be covered in graphite and diamond.

Researchers estimate that at least one-third of the new planet’s mass could be diamond.

The gemstone planet, called ’55 Cancri e’, has a radius twice that of Earth’s and a mass that’s eight times greater, making it a “super-Earth.”  The planet is one of five found orbiting ’55 Cancri’, a sun-like star about 40 light years from Earth.  Located in the constellation of Cancer, scientists say the star can be seen with the naked eye.

Astronomers first spotted the planet last year as it was transiting its star, which allowed them to measure its radius for the first time.  Using that information, along with their most recent estimate of its mass, researchers used computer modeling to speculate on the chemical composition of the planet.

Previous research revealed that the host star, 55 Cancri, has more carbon than it does oxygen, leading the US-French team to confirm that significant amounts of carbon and silicon carbide, with only a small amount of water ice, were available during the planet’s formation.

Star map showing the planet-hosting star 55 Cancri in the constellation of Cancer. The star is visible to the naked eye. (Image:Nikku Madhusudhan using Sky Map Online)

Astronomers initially assumed the diamond planet’s chemical composition was similar to Earth’s and that 55 Cancri e contained a substantial quantity of super-heated water.  However, according to Yale University researcher Nikku Madhusudhan, the new research suggests the planet has no water at all and is primarily made up of carbon – such as graphite and diamond – as well as iron, silicon carbide, and, possibly, some silicates.

The identification of a carbon-rich super-Earth means scientists can no longer assume that all distant rocky planets have chemical elements, interiors, atmospheres or biologies similar to Earth, according to Madhusudhan.

Which means there could be other gemstone planets out there just waiting to be discovered.

Eating breakfast may help keep you from getting fat and making poor food choices (Photo: Angela de Março via Flickr/Creative Commons)

Skipping breakfast sets the brain up to make poor food choices later in the day, according to a new study.

Scientists from the MRC Clinical Science Centre at London’s Imperial College, compared the brain scans and eating patterns of people both after eating breakfast and when they were fasting.

They found that those who avoid breakfast may overeat throughout the rest of the day, often choosing high-calorie or junk food over healthier selections.

The researchers studied the magnetic resonance images (MRIs) of 21 volunteer test subjects who didn’t eat anything before coming in for their tests.  On one those visits, the volunteers were first given a 750-calorie breakfast before the researchers ran the MRI scans.

On another visit to the research center, the test subjects weren’t fed any breakfast, but were always served lunch after each scanning session.

“Through both the participants’ MRI results and observations of how much they ate at lunch, we found ample evidence that fasting made people hungrier, and increased the appeal of high-calorie foods and the amount people ate,” said Dr. Tony Goldstone, who led the study.

Researchers believe the brain’s orbitofrontal cortex (highlighted in this MRI image) might play a key role in influencing food choices. (MRI Image: Paul Wicks via Wikimedia Commons)

While examining the MRIs of volunteers who hadn’t eaten breakfast, the scientists found a variation in the pattern of activity in the orbitofrontal cortex, that’s the area of the brain located right above the eyes that can affect decisions concerning the appeal and reward value of food.

When participants who were fasting or didn’t eat any breakfast were shown pictures of high-calorie food,  the MRIs showed that that portion of the brain was “activated,” a reaction less strong when they had eaten breakfast.

After studying and comparing the MRI scans over a period of time, the researchers were able to use the brain scans to predict which of their test subjects would be the mostly likely to respond strongly to high-calorie foods.

To Goldstone and his colleagues, these findings suggest  the orbitofrontal cortex may play a key role in influencing people in making their food choices.

They also say their research complements previous studies that show fasting may not be the best way to lose weight, since doing so tends to create a “bias” in the brain that makes us seek a high-calorie food reward.

Nutritionists recommend foods with protein (eggs/lean meat), whole grains, and fruits or vegetables, for a healthy breakfast (Photo: Kenji Ross via Flickr/Creative Commons)

Eating a healthy breakfast doesn’t necessarily mean sitting down to a formal meal or even eating traditional breakfast foods like cereals or eggs.

You can mix up the food items you want to eat for breakfast and that could also include eating some of those tasty leftovers from the previous night’s dinner.

Here are some tips and suggestions on healthy breakfast choices from the Academy of Nutrition and Dietetics:

• Include some lean protein, such as eggs, cheese, deli meat, peanut butter, Canadian bacon or yogurt
• Pair that lean protein with a whole-grain carbohydrate food, such as a whole-grain cereal, bread, waffles, pancakes or oatmeal
• Be sure to include fruits and vegetables to your breakfast  Top off yogurt with some fruit or chop up some veggies to add to your omelet
• To save time, nutritionists suggest prepping breakfast the night before

The newly discovered planet PH1 is depicted in this artist’s rendition transiting the larger of the its two host stars. Left of the planet, off in the distance, is a second pair of stars that orbit PH1. (Image: Haven Giguere/Yale)

The recent discovery of a four-star planet highlights the growing value of citizen scientists, non-professional enthusiasts – including  hobbyists, educators and amateur scientists – who participate in scientific endeavors.

The discovery of the extrasolar planet dubbed PH1, which orbits twin suns and is itself orbited by a second distant pair of stars, was made through the combined efforts of volunteer citizen scientists and  professional astronomers.

The amateur scientists behind the sighting of the phenomenon, called a “circumbinary planet in a four-star system,” were able to get involved with astronomical research through the website Planethunters.org, a collaboration between Yale University and the online citizen science project Zooniverse.

“Planet Hunters is a symbiotic project, pairing the discovery power of the people with follow-up by a team of astronomers,” says Debra Fischer, a planet expert and professor of astronomy at Yale, who helped launch the website in 2010. “This unique system might have been entirely missed if not for the sharp eyes of the public.”

Through Planethunters.org, volunteers help professional astronomers sift through mountains of data  gathered by NASA’s Kepler space mission.

That assistance includes brightness measurements, or “light curves,” for more than 150,000 stars, taken by instruments aboard Kepler  every 30 minutes.

Artist’s rendition of the newly discovered circumbinary planet PH1 that orbits two suns (upper left) and is 5,000 light years from Earth. (Image: Haven Giguere/Yale)

The Planet Hunters pour through the data looking for possible transit events, a brief dip in brightness that occurs when a planet or other celestial body passes in front of the star.

“The thousands of people who are involved with Planet Hunters are performing a valuable service,” says Jerome Orosz, associate professor of astronomy at San Diego State University and co-author of the paper outlining PH1’s discovery. “Many of the automated techniques used to find interesting features in the Kepler data don’t always work as efficiently as we would like. The hard work of the Planet Hunters helps ensure that important discoveries are not falling through the cracks.”

PH1, some 5000 light years from Earth, has been described by astronomers as a gas giant planet slightly bigger than Neptune.  It takes the extrasolar planet 138 days to complete an orbit around its two host stars, which have masses about 1.5 and 0.41 times that of the sun and also circle each other once every 20 days.  The two distant stars that orbit the new-found planet are about 144,840,960,000 km away, roughly 1000 times the distance between the Earth and the Sun.

Yale’s Meg Schwamb of Yale, the lead author of the paper said that the circumbinary planets that are being discovered are the extremes of planet formation.

“The discovery of these systems is forcing us to go back to the drawing board to understand how such planets can assemble and evolve in these dynamically challenging environments.”

Games and applications designed for computers and platforms such as smartphones and tablets have become important tools in providing an effective, yet fun learning experience. (Photo: Jesse Knish Photography for GDC Online via Flickr/Creative Commons)

Educators, businesses, public service organizations and media outlets have all discovered that developing and offering a variety of computer and smartphone games and applications is a successful way to engage and communicate with their audiences as well as providing challenging, but entertaining learning opportunities.

The U.N. Alliance of Civilizations (UNAOC) also sees the growing value and importance that these digital games offer, so they recently launched “Create UNAOC 2012.” It’s a global competition that will award cash prizes to creators and developers of computer games and apps that promote intercultural dialogue and understanding.  The Voice of America is also a partner with the UNAOC for this contest.

With “Create UNAOC 2012” in mind, more than 20 VOA Journalists, web editors, computer program developers and experts in developing educational games — like Alex Chisholm from the Learning Games Network and Scot Osterweil of the MIT Education Arcade — gathered last Thursday (10/11/12), at VOA headquarters in Washington for something called a “Game Jam.”

A Game Jam is a gathering of people with a variety of backgrounds and skills, along with experts like Chisholm and Osterweil who discuss goals and brainstorms game ideas that would offer an entertaining and fun playing experience, but also provide a unique learning opportunity as well.

The participants in the VOA Game Jam were divided into teams that worked on coming up with new and fresh ideas for games that will be able help VOA effectively communicate and better connect with its ever-changing worldwide audience.

With the Game Jam in full swing, and the participants fully engaged in brainstorming ideas for new games, organizers said that there were at least five or six good ideas for possible game development.

VOA Game Jam participants listen to a presentation by Scot Osterweil, Creative Director of the MIT Education Arcade on how to create games that not only teach but are also entertaining and fun. (Photo: VOA)

The room, where the Game Jam was being held, buzzed with exciting and animated discussion as the participants worked out their ideas, talked about how their games should look, and function as well as what would be needed to make them fun.

Among the some of the game ideas that were discussed was an immigration game, where the player does a little role playing and virtually experiences what an immigrant could face in moving to a new country.  Another, from VOA’s “Learning English,” proposes a fun way to learn the English language.

After last Thursday’s brainstorming session, the proposed games will be evaluated, with the most promising game ideas selected to continue development into a finished product that will be made available to the VOA audience.

With the Voice of America broadcasting in more than 40 languages, the games selected to be developed could be produced in a number of different languages.  But since it represents VOA’s largest web audience, it’s probable that several of the games will be in English.

While developing and producing a finished game product is an involved process, it’s hoped that it will take about two to three months to develop and produce a finished game. The first games could be released sometime in early 2013.

If you’re 13 or older, you too can take part in the “Create UNAOC 2012” and be eligible for a nice cash prize.  Just visit the Create UNAOC 2012 website for more information.  Keep in mind, though, that you’ve got only to the end of November to get your entry in for this contest.

Many factors influence a woman’s self-perception of physical attractiveness. New research shows that genetics may also play a role in how some women gauge their body image. (Photo: Christine Tremoulet via Flickr/Creative Commons)

While cultural and societal factors have long been thought to influence how women see themselves in the mirror, a new study in Michigan has revealed that genetics may also play a role in making some women more vulnerable to the pressure of being thin.

Many people today, especially women, have taken the modern axiom, “Thin is In“ to heart.  So much so that a number of those pushing themselves to lose weight in order to become thin have developed serious problems such as the potentially deadly eating disorder, Anorexia Nervosa.

Women are constantly reminded by the media that it’s best to be thin.  From size-zero models to airbrushed film stars, thinness is portrayed as equaling beauty across Western culture. While both genders are subject to this pressure, it tends to fall harder on women for a variety of reasons. That skinny ideal can cause women to have a poor body image in the way they see themselves and imagine how they look.

Michigan State University researcher Jessica Suisman led a study that focused on the possible psychological impact of women who actually believe this perceived ideal of thinness, something the researchers called “thin-ideal internalization.”

Ms. Suisman and her colleagues gathered more than 300 female twins, from 12 to 22 years of age, from the Michigan State University Twin Registry, to participate in the study.  The researchers first made a measurement of the women’s “thin idealization” — or just how much their study subjects wanted to look like the thin women who are often shown on TV and in magazines.

In western cultures women are constantly reminded by the media that it’s best to be thin. (Photo: Helga Weber via Flickr/Creative Commons)

Once these measurements were made, the researchers then compared the genetics of identical twins, who share 100 percent of their genes, with those of fraternal twins who share 50 percent.

The researchers, examining the results of these measurements found that identical twins have a close to identical level of thin idealization than their fraternal twin cohorts.  To Suisman and her colleagues this suggests that genetics play a significant role in pressuring women to believe that they need to be thin (“thin idealization”).

As they continued their analysis of the data, the researchers found that the heritability of thin idealization is 43 percent, which they believe means that nearly half of the reasons women differed in their idealization of thinness can be explained by variations in their genetic makeup.

But Suisman pointed out that their research did not find a specific gene that makes a woman think, ‘I want to be thin.’  “That wouldn’t make any sense because we haven’t always had these thin models as our ideals,” said Suisman.   “We aren’t sure exactly what these same genes would have done many years ago or even in a different culture in the world where thinness isn’t seen as the equivalent for beauty,” she adds.

Suisman’s research team also looked at what environmental influences, such as friends, family, society and/or culture, were most important in determining how women felt about their bodies and how much they wanted to look like the ‘media ideal.’

A study led by Jessica Suisman, from Michigan State University, suggests that, for some women, genes may influence the pressure to be thin. (Photo: Michigan State University)

“And what we actually found was that environmental influences that were really specific to each individual woman, rather than the general environment was more important,” said Suisman.  In other words, individual experiences such as having friends and peers who are focused on thinness, or being involved in a sport that’s also focused on thinness, were more important and played more of a role in pressuring women to be thin than general societal and cultural influences.

“The take-home message,” Suisman said, “is that the broad cultural risk factors that we thought were most influential in the development of thin-ideal internalization are not as important as genetic risk and environmental risk factors that are specific and unique to each twin.”

Jessica Suisman joins us this weekend on the radio edition of Science World.  She tells us more about her research and findings and how genetics could play a role in pushing women to focus on being thin.

Check out the right column for scheduled air-times or listen now to the interview below.