Jason Carr |

13May 2013

Riding Hexapod Walkers on Dusty Alien Worlds

Speculative fiction is the home of countless machines that fly in space, yet resemble humanoid lifeforms. Scientists are now working on the next generation of robots that will blaze a trail in space by going where humans simply can’t maneuver on their own. Like so many things in the field of space exploration, the descendents of those working on these projects will be the ones to really reap the benefits of this research.

That being said, some scientists and engineers are beginning to consider the possibility of new types of craft that use human pilots while incorporating robotic structures to facilitate planetary exploration. Numerous remotely tele-operated vehicles like the Lunakhod and the Sojourner have already been used with great success to explore extraterrestrial surfaces. The use of human pilots in these past missions would of course been foolish, however, as technology advances it’s somewhat easier to believe that such endeavors in the future may be realistic. Robotics will undoubtedly become increasingly important as space travel becomes commonplace in the years ahead. Automatic piloting aren’t the only thing that these units will be useful for, however. Semiautonomous navigation devices are old news. Treads won’t be able to explore extremely treacherous terrain on rocky worlds. We need to figure out ways to get humans involved in planetary surface exploration.

One viable option to accomplish this may involve hexapod walkers similar to the one shown above. These units would be far more stable over irregular terrain than treads or wheels. Astronauts landing on other planets wouldn’t be able to work with equipment that’s as straightforward as the buggy used on the Apollo 15, 16 and 17 missions. By using six symmetrical legs, new robotic vehicles could descend vast gorges without tumbling the way conventional vehicles do.

Robotic algorithms can do more than merely pilot units as well. As brain interfaces become safer, astronauts may be able to directly interface with their vehicles. Hexapod legs could actually become extensions of their physical bodies. Some people have proposed constructing piloted robotic vehicles that look like some form of giant humans in order to speed up the learning process. Nevertheless, the human body isn’t exactly a great thing to model a machine after. While the human body might be balanced in its organic form, it wouldn’t really work as a machine. Humans require liquid in the inner ear canal to remain balanced. Hexapod units derive balance from their structure.

Interestingly, not all of a six-legged robot’s legs are necessary to remain upright. If a few of the legs were damaged, it might be able to still move. That makes this design particularly useful for astronauts who would be operating away from technical crews in extremely hazardous environments. Training problems might still be pretty serious, which is why some people have proposed chicken walkers and numerous other sophisticated designs as alternatives.

Conclusion

Industrial robotics have been used in spacecraft rendezvous and docking simulation conditions so these may be the best approach in the future once we figure out how to get humans to planetary bodies. It’s not hard to believe their use will continue to grow as we continue to push the boundaries of space exploration in the future. As we continue moving forward with our space exploration efforts, the involvement of humans should be considered as increases in our technological capabilities are realized. Brain interfaces and walker units may be integral components in these future planetary exploration efforts.

Reference:

Toralf Boge, & Ou Ma (2011). Using Advanced Industrial Robotics for Spacecraft Rendezvous and Docking simulation Robotics and Automation (ICRA), 1-4 DOI: 10.1109/ICRA.2011.5980583

Wilcox, B. (1992). Robotic vehicles for planetary exploration Applied Intelligence, 2 (2), 181-193 DOI: 10.1007/BF00058762

09May 2013

Study Finds Brain System for Emotional Self-Control

Jason Carr ⋅ 2 Comments

Different brain areas are activated when we choose to suppress an emotion, compared to when we are instructed to inhibit an emotion, according a new study from the UCL Institute of Cognitive Neuroscience and Ghent University.

In this study, published in Brain Structure and Function (citation below), the researchers scanned the brains of healthy participants and found that key brain systems were activated when choosing for oneself to suppress an emotion. They had previously linked this brain area to deciding to inhibit movement.

“This result shows that emotional self-control involves a quite different brain system from simply being told how to respond emotionally,” said lead author Dr. Simone Kuhn (Ghent University).

In most previous studies, participants were instructed to feel or inhibit an emotional response. However, in everyday life we are rarely told to suppress our emotions, and usually have to decide ourselves whether to feel or control our emotions.

In this new study the researchers showed fifteen healthy women unpleasant or frightening pictures. The participants were given a choice to feel the emotion elicited by the image, or alternatively to inhibit the emotion, by distancing themselves through an act of self-control.

The researchers used functional magnetic resonance imaging (fMRI) to scan the brains of the participants. They compared this brain activity to another experiment where the participants were instructed to feel or inhibit their emotions, rather than choose for themselves.

Different parts of the brain were activated in the two situations. When participants decided for themselves to inhibit negative emotions, the scientists found activation in the dorso-medial prefrontal area of the brain. They had previously linked this brain area to deciding to inhibit movement.

In contrast, when participants were instructed by the experimenter to inhibit the emotion, a second, more lateral area was activated.

“We think controlling one’s emotions and controlling one’s behaviour involve overlapping mechanisms,” said Dr. Kuhn.

“We should distinguish between voluntary and instructed control of emotions, in the same way as we can distinguish between making up our own mind about what do, versus following instructions.”

Regulating emotions is part of our daily life, and is important for our mental health. For example, many people have to conquer fear of speaking in public, while some professionals such as health-care workers and firemen have to maintain an emotional distance from unpleasant or distressing scenes that occur in their jobs.

Professor Patrick Haggard (UCL Institute of Cognitive Neuroscience) co-author of the paper said the brain mechanism identified in this study could be a potential target for therapies.

“The ability to manage one’s own emotions is affected in many mental health conditions, so identifying this mechanism opens interesting possibilities for future research.

“Most studies of emotion processing in the brain simply assume that people passively receive emotional stimuli, and automatically feel the corresponding emotion. In contrast, the area we have identified may contribute to some individuals’ ability to rise above particular emotional situations.

“This kind of self-control mechanism may have positive aspects, for example making people less vulnerable to excessive emotion. But altered function of this brain area could also potentially lead to difficulties in responding appropriately to emotional situations.”

Source: University College London

Reference:

Kühn, S., Haggard, P., & Brass, M. (2013). Differences between endogenous and exogenous emotion inhibition in the human brain Brain Structure and Function DOI: 10.1007/s00429-013-0556-0

08May 2013

The 5 Greatest Astronomers Throughout History

Jason Carr ⋅ 2 Comments

Throughout history, there have been countless astronomers who have made an impact on man’s knowledge of the universe. While each small discovery certainly has scientific worth, there have also been several forward-thinking scientists who stand out as the greatest astronomers of all time. By boldly rethinking conventional beliefs about the nature of the universe, these 5 astronomers have truly revolutionized mankind’s knowledge of space and of the planet Earth.

Copernicus, Nicolaus (1473-1543)

Copernicus was a Polish astronomer who first theorized that the long-standing geocentric model of the universe was incorrect, and that the Earth and other celestial bodies instead moved around the Sun. His introduction to this idea, the Commentariolus, was his first heliocentric writing, and his book On the Revolutions expounded on these concepts. Although his work was very controversial at the time, Copernicus has since become one of the greatest astronomers in history because his revolutionary theories paved the way for modern astronomy.

Galileo, Galilei (1564-1642)

Not only is Galileo considered to be one of the greatest astronomers of all time, but he is also often referred to as “The Father of Modern Science”. He was the first person to methodically study space with a telescope, and his observations provided conclusive scientific evidence that the heliocentric model of the universe posited by Copernicus was indeed correct. He also discovered the phases of Venus, the moons of Jupiter, and the dark marks, which were later named sunspots, on the surface of the Sun.

Halley, Edmond (1656-1742)

English astronomer Edmond Halley is best known for being the first person to discover and calculate the orbit of a comet. His theory that comets’ orbits are periodic was proven when he correctly predicted that a comet observed in 1682 (later named Halley’s Comet) would again be seen in 76 years. Halley also personally catalogued the positions of nearly 350 stars (an extraordinary feat at the time), and introduced the notion of stellar proper motions, a theory stating that although stars seem to remain in a fixed position, they actually have a small, independent movement of their own.

Herschel, William (1738-1822)

Herschel’s journey towards becoming one of the greatest astronomers in history began with a love of building telescopes. He constructed over 400 telescopes during his lifetime, including the famous Herschelian telescope, an enormous reflecting telescope. Using his innovative designs, Herschel was able to discover Uranus, as well as two of the planet’s major moons, Oberon and Titania. He also discovered two of Saturn’s moons, and was the first person to observe that the solar system wasn’t stationary, but was in fact moving through the universe.

Hubble, Edwin (1889-1953)

Often said to be the “Father of Observational Cosmology”, Hubble was an American astronomer who was the first person to view distant space beyond Pluto, and in doing so changed the world’s view of the cosmos forever by discovering and classifying many galaxies that were unknown at the time. With the formulation of Hubble’s Law in 1929, he also proved that the universe was not in a fixed position but was actually expanding; a radical concept that eventually inspired the creation of the Big Bang Theory.

A great astronomer not only makes new discoveries, but also challenges conventional thought with groundbreaking ideas that further mankind’s knowledge of the universe. The crucial insights of these extraordinary scientists have solidified their position as 5 of the greatest astronomers in human history.

06May 2013

Why America Desperately Needs More Scientists & Engineers

Jason Carr ⋅ 3 Comments

Studies have shown that the number of jobs available in the United States is directly related to advances made in science and engineering. Education experts feel that if America has few leaders developing the technological advances that will create the jobs of the future, then the future will hold few opportunities for our young workers.

With only about 4% of college graduates receiving degrees in engineering or science (source), the United States is ahead of Bangladesh, Cambodia, and Cameroon. However, it is behind most other nations, and certainly at the bottom of the list of developed countries. Since 50-85% of job growth in the U.S. is dependent on scientists and engineers, our ability to turn out graduates in STEM-related fields is more important than ever.

[Note: STEM is an acronym for science, technology, engineering, math.]

Consider this. It took 700 engineers to create the iPod, which then led to the creation of 14,000 more jobs in the U.S. alone (source). During the development of the iPhone/iPad, most of the engineering work was completed outside the U.S. Apple and its contractors currently employ over 700,000 people in other nations because of the availability of engineers in those countries. Prior to his death, Steve Jobs is said to have told President Obama that the reason Apple directly or indirectly employs these 700,000 people outside the United States is because it can’t find 30,000 engineers in the United States.

Some may claim that companies like Apple are using this as an excuse – that the U.S. does produce enough engineers/scientists, but are instead driven by profit (hiring overseas is cheaper). This may be the case in some instances, however the numbers don’t lie (source):

PhD Engineering Graduates (U.S.)
U.S. Citizens/Permanent Residents:
1998 = 53.39%
2009 = 42.78%

Temporary Visa Holders
1998 = 46.61%
2009 = 57.22%

It would be foolish to assume that the vast majority of temporary visa holders are remaining in the U.S. to fill jobs once they’ve completed their education. As indicated above, we’re clearly seeing a decline in U.S. PhD levels. While some companies may be sourcing jobs overseas for economic reasons, I think this is the exception rather than the rule. It stands to reason that if America successfully increases the number of STEM graduates it produces, thousands (if not millions) of new jobs will increase in direct proportion to the increase in technological advances these STEM graduates will produce.

A Broken Educational System

Training enough scientists and engineers in the near future will not be an easy task, since our educational system is not producing enough high school graduates who are prepared for demanding college courses. In fact, some college freshmen are actually advised to take easier classes in order to assure that they make good enough grades to graduate.

Several years ago (2005), the National Academies of Science, Engineering, and Medicine established a committee to study what needs to be done to encourage more young people to take tougher classes, both in high school and college. They issued a report called, The Gathering Storm, that made recommendations for fixing the nation’s K-12 public education system. They found that not only are we not producing enough scientists/engineers, we are also alarmingly bad at producing high school graduates. Most recently (2010), the organizations released a new report, Rising Above the Gathering Storm, Revisited [PDF], which states that the situation in the U.S. has become even more bleak. Today, the U.S. has one of the highest secondary school dropout rates in the developed world. Even our top students are falling behind. American 15-year-olds have been ranked 17th in science and 25th in math when tested against the 34 most developed nations. In 2011, they dropped to 32nd in math against the same 34 countries (source). Meanwhile, it is estimated that of every 3,100 8th graders in America, only one will go on to get a PH.D. in engineering or science.

While we are falling further behind, other countries are stepping up their investments in science education. A $2 billion investment from the Russian government has opened up so many science and engineering educational sites in Tomsk that that Siberian town has become the center of Russia’s IT industry. The King Abdullah University of Science and Technology opened in 2009 in Saudi Arabia with an endowment greater than that of the Massachusetts Institute of Technology. China is providing scholarships for over 200,000 of its students to study abroad in the fields of science and engineering every year. The United Kingdom is increasing its investment in non-defense research and development by 25%. India is investing in nanotechnology education hoping to become a hub for that industry.

The original ‘Gathering Storm’ and the follow-up reports have attracted high-level interest and some steps have been taken towards making educational improvements that will lead to more job creation at home. Overall however, U.S. officials have largely ignored the reports in a rush to save money by defunding education. Instead of investing more in its students, we continue to see the closing of university departments in science fields. Officials justify their reasoning by claiming that few American students elect to take science courses in college anyway, so why waste funds on them?

Where We Are Today

In his 2013 State of the Union address, President Obama called for a $71B increase in Department of Education funding directly focused on STEM (source). While this is a step in the right direction, my guess is that this will have little/no significant impact on the numbers I outlined above if changes aren’t made in other areas as well. A recent report [PDF] by the Center on Budget and Policy Priorities (CBPP) indicates that states are spending, on average, 28% less per student in fiscal year 2013 than they were in 2008 while college tuition costs continue to climb. While the CBPP indicates this is a result of states not raising taxes (not something I necessarily agree with), the chart below is indicative of a growing problem.

The Bottom Line

The U.S. needs to produce more scientists and engineers in the future. I don’t believe for a minute that our young people are to blame for the declines discussed above. Nor do I believe that closing doors to them in these fields in the quest to save money is the right approach either. This is a matter of readjusting our national educational priority.

STEM needs to be a PRIMARY focus in education throughout our students’ K-12 years. I’m not claiming that important subjects such as art, music, literature, and language aren’t necessary components of a well-rounded education. Of course they are. I’m simply advocating a change in our approach to education and stating that the primary emphasis, moving forward, instead focus on better preparing our students for success in STEM-related fields. As long as we continue to force our teachers to “teach to a test” (Read: No Child Left Behind) however, we will continue to churn out a greater number of students that are woefully unprepared for the rigors required to complete collegiate-level STEM programs. This in turn will lead to a continuing decrease in the number of scientists/engineers in America. As this happens, the country will invariably continue to fall behind the rest of the developed world in technological innovation and leadership. Is that what we really want for our kids and future generations? I certainly don’t.

02May 2013

Meteorites May Reveal Mars’ Secrets of Life

Jason Carr ⋅ 2 Comments

In an effort to determine if conditions were ever right on Mars to sustain life, a team of scientists, including a Michigan State University professor, has examined a meteorite that formed on the red planet more than a billion years ago.

And although this team’s work is not specifically solving the mystery, it is laying the groundwork for future researchers to answer this age-old question.

The problem, said MSU geological sciences professor Michael Velbel, is that most meteorites that originated on Mars arrived on Earth so long ago that now they have characteristics that tell of their life on Earth, obscuring any clues it might offer about their time on Mars.

“These meteorites contain water-related mineral and chemical signatures that can signify habitable conditions,” he said. “The trouble is by the time most of these meteorites have been lying around on Earth they pick up signatures that look just like habitable environments, because they are. Earth, obviously, is habitable.

“If we could somehow prove the signature on the meteorite was from before it came to Earth, that would be telling us about Mars.”

Specifically, the team found mineral and chemical signatures on the rocks that indicated terrestrial weathering – changes that took place on Earth. The identification of these types of changes will provide valuable clues as scientists continue to examine the meteorites.

“Our contribution is to provide additional depth and a little broader view than some work has done before in sorting out those two kinds of water-related alterations – the ones that happened on Earth and the ones that happened on Mars,” Velbel said.

Image Credit: Michigan State University

The meteorite that Velbel and his colleagues examined – known as a nakhlite meteorite – was recovered in 2003 in the Miller Range of Antarctica. About the size of a tennis ball and weighing in at one-and-a-half pounds, the meteorite was one of hundreds recovered from that area.

Velbel said past examinations of meteorites that originated on Mars, as well as satellite and Rover data, prove water once existed on Mars, which is the fourth planet from the sun and Earth’s nearest Solar System neighbor.

“However,” he said, “until a Mars mission successfully returns samples from Mars, mineralogical studies of geochemical processes on Mars will continue to depend heavily on data from meteorites.”

Velbel is currently serving as a senior fellow at the Smithsonian Institution’s National Museum of Natural History in Washington D.C.

The research is published in Geochimica et Cosmochimica Acta (citation below), a bi-weekly journal co-sponsored by two professional societies, the Geochemical Society and the Meteoritical Society.

Source: Michigan State University

Reference:

Stopar, J., Taylor, G., Velbel, M., Norman, M., Vicenzi, E., & Hallis, L. (2013). Element abundances, patterns, and mobility in Nakhlite Miller Range 03346 and implications for aqueous alteration Geochimica et Cosmochimica Acta, 112, 208-225 DOI: 10.1016/j.gca.2013.02.024

01May 2013

Human Brain vs. Supercomputer

Jason Carr ⋅ 3 Comments

The Blue Gene/Q Sequoia. (Image via IBM)

Last November, IBM revealed that its lightning speed, Blue Gene/Q Sequoia supercomputer achieved a record simulation of more than 530 billion neurons. The Blue Gene/ Q Sequoia can perform over 16 quadrillion calculations per second, ranking as the second-fastest supercomputer in the world. (The number one spot is held by Cray’s Titan, built by the Oak Ridge Laboratory in Tennessee.)

So the question arises…

Is the human brain, in fact, smarter than a supercomputer with these capabilities? Kwabena Boahen, Ph.D. professor at Stanford University and director of the Brains in Silicon Research Laboratory says it is.

“The brain is actually able to do more calculations per second than even the fastest supercomputer,” said Boahen.

Of course, the brain makes a single calculation much slower than a supercomputer, but the brain can actually execute more calculations per second because it is “massively parallel.” What this means is that networks of neurons actually work together to simultaneously solve many problems at once. However, in computing platforms, each step must be completed before the next step begins.

Creating the brain simulator

Boahen and researchers at his laboratory have worked to create a replica of the brain’s computing abilities using original hardware and software applications. So far what they’ve developed is a computing platform that mimics the activity of one million neurons. (Not quite the amount that are in the human brain.)

Two graduate students from Stanford University worked with Boahen to develop the Neurogrid. (Image credit: Samir Menon/ Stanford University)

What separates their platform, which they’ve named “Neurogrid,” from a supercomputer, is that it’s the first simulation platform that can model one million neurons in real time, and therefore offers researchers a compelling tool for studying the human brain.

Neurogrid contains 16 chips, each containing over 65,000 silicon “neurons.” The neurons’ activity can be programmed according to about 80 factors, which grants researchers the ability to mimic the unique characteristics of different kinds of neurons. The soft-wired “synapses” intersect across the board and shut signals between the simulated neurons and the thousands of neurons they are connected with. This set up creates an accurate representation of what kind of communication actually takes place in the brain.

Why is the Neurogrid more effective than a supercomputer?

So far, findings show that the Blue Gene/ Q Sequoia supercomputer’s simulation took 1,500 times longer than it would take the brain to do the same activity. Even more affordable brain simulators that use computing powers such as central and graphical processing units are slower than the brain.
“Neurogrid doesn’t take an hour to simulate a second of brain activity. It takes a second to simulate a second of brain activity,” said Boahen.

The Neurogrid is also more energy efficient than a supercomputer, using a fraction of the energy. The Blue Gene/ Q Sequoia uses 8 megawatts of electricity (that’s enough to power 160,000 homes) while the Neurogrid uses just 5 watts (enough to power just one cellphone charger).

Future impact

Neurogrid will not only be able to help researchers discover more about the inner workings of the brain, but also has the potential to reveal more about diseases such as autism and schizophrenia. Neurogrid can also be used to create new systems for advancements in neural prosthetics and robotic controllers.

Source: Hearst Electronics Products Magazine.

01May 2013

Synthetic Biology Research on the Rise

Jason Carr ⋅ 1 Comment

The number of private and public entities conducting research in synthetic biology worldwide grew significantly between 2009 and 2013, according to the latest version of an interactive map produced by the Synthetic Biology Project at the Woodrow Wilson International Center for Scholars. The map is available online at http://www.synbioproject.org/map.

Synthetic biology, an area of research focused on the design and construction of new biological parts and devices, or the re-design of existing biological systems, is an emerging field and the focus of labs and companies around the world. The map, which builds on work the project started in 2009, is populated with more than 500 companies, universities, research institutions and other entities working on synthetic biology, showing clusters of activity in California, Massachusetts, Western Europe and East Asia.

“Part of this new activity has been driven by continuing government investments in the science,” said David Rejeski, who directs the Synthetic Biology Project. “Another important factor has been the rapidly declining costs of gene sequencing, which has supported more effective approaches to engineering biological systems.”

The Synthetic Biology Project found that the number of companies conducting synthetic biology research increased three-fold since 2009. A plurality of the companies involved in synthetic biology is focusing on developing bio-based specialty chemicals, fuels and/or medicines.

Since 2009, the industry has also experienced moderate levels of consolidation and failure. Of the 61 companies included on the initial 2009 inventory, six were acquired by other companies, closed their doors or can longer be identified. An additional 11 companies that were tracked between the release of the 2009 inventory and the 2013 update were also acquired, closed or cannot be identified.

In addition to the expanded listings, the updated map features improved functionality, more detailed information and additional categories and subcategories. The updated map can also be accessed on Android and Apple mobile devices.

The 2013 analysis can be found here: http://www.synbioproject.org/process/assets/files/6302/_draft/findings_2013.pdf

The map will be updated periodically. Users can submit additional entries to the map using this online form: http://www.synbioproject.org/sbmap/add-item/

Source: Woodrow Wilson International Center for Scholars/Science and Technology Innovation Program

29Apr 2013

Early Childhood Education: the Importance of Phonological Awareness

Jason Carr ⋅ 8 Comments

There are many factors that go into how a child learns to read, write, and spell. Phonological awareness in early childhood is a proven predictor of how well a child will progress in their literary performance. Today’s post explains the basics of phonological awareness and how to better develop it in young children.

What is Phonological Awareness?

Phonological awareness refers to a child’s ability to understand the sound patterns that are specific to the language that the child is exposed to on a regular basis. There are many skills that are involved in understanding phonemes, some of which include being the following:

The ability to detect rhyming words
The ability to segment words into syllables
Identifying the letters of the alphabet and their sounds
Identifying the letters that words begin and end with
Recognizing blended sounds
The ability to manipulate sounds in words by adding, substituting or deleting letters

Development of phonetic awareness skills begin gradually and build sequentially upon each other throughout the preschool and early elementary period. Although phonological awareness is taught when a child enters the school system, research shows that the more a child knows before he or she enters school, the faster they are able to learn to read, write, and spell. In fact, these fundamental skills are strong predictors of literacy performance in subsequent years. Many researchers believe that phonological awareness in early childhood is more important to literacy than other variables such as socioeconomic status or intelligence.

How the Awareness of Phonetics is Developed

Phonological awareness develops primarily through different types of word play. Reading books to children that focus on sounds, alliteration, and rhyming promotes awareness of the sounds that different letters make, builds vocabulary, and increases awareness of the beginning and ending sounds of words. Playing word games such as generating rhyming words or naming things that start with a certain letter are very helpful in developing an awareness of phonics as well as understanding syllables and blended sounds. After they enter the school system, children who have relatively good phonological awareness are able to further their literacy skills with a strategy called invented spelling. This skill is a child’s way to guessing at how to spell words by applying the knowledge about their language that they have acquired thus far. Through this strategy children learn the correct letters and annunciation of their particular language system faster.

Phonological awareness is a critical skill that affects a child’s ability to learn to understand the structures of their native language. Statistics indicate that in order to acquire fluency at reading and efficiency at spelling sooner, a child should be phonetically aware before they enter the school system. Some easy ways that parents can develop phonetic awareness is to read to children, teach them nursery rhymes, and play word games with them.

Reference:

Lonigan CJ, Farver JM, Nakamoto J, & Eppe S (2013). Developmental Trajectories of Preschool Early Literacy Skills: A Comparison of Language-Minority and Monolingual-English Children. Developmental psychology PMID: 23316767

Carson KL, Gillon GT, & Boustead TM (2012). Classroom Phonological Awareness Instruction and Literacy Outcomes In the First Year of School. Language, speech, and hearing services in schools PMID: 23275432

Chipere, N. (2013). Sex differences in phonological awareness and reading ability Language Awareness, 1-15 DOI: 10.1080/09658416.2013.774007

Wagensveld B, van Alphen P, Segers E, Hagoort P, & Verhoeven L (2013). The neural correlates of rhyme awareness in preliterate and literate children. Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology PMID: 23523114

25Apr 2013

Newborn Stars and their Effect on the Universe

Jason Carr ⋅ 3 Comments

When galaxies form new stars, they sometimes do so in frantic episodes of activity known as starbursts. These events were commonplace in the early Universe, but are rarer in nearby galaxies.

During these bursts, hundreds of millions of stars are born, and their combined effect can drive a powerful wind that travels out of the galaxy. These winds were known to affect their host galaxy — but this new research [Paper here - PDF] now shows that they have a significantly greater effect than previously thought.

An international team of astronomers observed 20 nearby galaxies, some of which were known to be undergoing a starburst. They found that the winds accompanying these star formation processes were capable of ionizing [1] gas up to 650 000 light-years from the galactic center — around twenty times further out than the visible size of the galaxy. This is the first direct observational evidence of local starbursts impacting the bulk of the gas around their host galaxy, and has important consequences for how that galaxy continues to evolve and form stars.

“The extended material around galaxies is hard to study, as it’s so faint,” says team member Vivienne Wild of the University of St. Andrews. “But it’s important — these envelopes of cool gas hold vital clues about how galaxies grow, process mass and energy, and finally die. We’re exploring a new frontier in galaxy evolution!”

The team used the Cosmic Origins Spectrograph (COS) instrument [2] on the NASA/ESA Hubble Space Telescope to analyze light from a mixed sample of starburst and control galaxies. They were able to probe these faint envelopes by exploiting even more distant objects — quasars, the intensely luminous centers of distant galaxies powered by huge black holes. By analyzing the light from these quasars after it passed through the foreground galaxies, the team could probe the galaxies themselves.

“Hubble is the only observatory that can carry out the observations necessary for a study like this,” says lead author Sanchayeeta Borthakur, of Johns Hopkins University. “We needed a space-based telescope to probe the hot gas, and the only instrument capable of measuring the extended envelopes of galaxies is COS.”

The starburst galaxies within the sample were seen to have large amounts of highly ionized gas in their halos — but the galaxies that were not undergoing a starburst did not. The team found that this ionization was caused by the energetic winds created alongside newly forming stars.

This has consequences for the future of the galaxies hosting the starbursts. Galaxies grow by accreting gas from the space surrounding them, and converting this gas into stars. As these winds ionize the future fuel reservoir of gas in the galaxy’s envelope, the availability of cool gas falls — regulating any future star formation.

“Starbursts are important phenomena — they not only dictate the future evolution of a single galaxy, but also influence the cycle of matter and energy in the Universe as a whole,” says team member Timothy Heckman, of Johns Hopkins University. “The envelopes of galaxies are the interface between galaxies and the rest of the Universe — and we’re just beginning to fully explore the processes at work within them.”

Source: ESA/Hubble Information Centre

Notes

[1] A gas is said to be ionised when its atoms have lost one or more electrons — in this case by energetic winds exciting galactic gas and knocking electrons out of the atoms within.

[2] Spectrographs are instruments that break light into its constituent colours and measure the intensity of each colour, revealing information about the object emitting the light — such as its chemical composition, temperature, density, or velocity.

Reference:

Sanchayeeta Borthakur, Timothy Heckman, David Strickland, Vivienne Wild, & David Schiminovich (2013). The Impact of Starbursts on the Circumgalactic Medium The Astrophysical Journal arXiv: 1303.1183v2

24Apr 2013

What if the Darwinists and Creationists Are Wrong?

Jason Carr ⋅ 2 Comments

Very little is really known about the origins of man because – as is the case with so many branches of science – new discoveries are constantly displacing old theories. Mankind is still largely viewed in Darwinian terms, except by those who subscribe to the beliefs of Christianity and the explanation of creation offered in the Book of Genesis. This biblical account at least grants us the dignity of a soul and a loving creator – or at least, a creator who cared enough to bother to give us life. But many people have grown dissatisfied with both of these stories about mankind’s origins, feeling that they do our race a disservice. Of course, there are also those that believe that Earth may have been “seeded” via another planetary body or even aliens. This concept of panspermia may seem outlandish but then, so is the fact that life seemingly “appeared” on Earth a few billion years ago. There’s no real evidence to support this theory but then, it’s not entirely beyond the realm of possibility either.

For as long as we’ve been self-aware and able to reflect upon our own existence, we’ve created myths and theories to account for how we got here. More often than not, when we ask, “Where did we come from, and why are we here?” what we’re really wondering is, “Of what inherent value – if any – is my life?”

If the answer you cling to is that your life is the random result of accidental chemical reactions followed by a survival of the fittest evolutionary process, then your ideas about the value of human life are bound to be pessimistic. The prevailing scientific view holds no room for any sacred purpose behind our existence. If, on the other hand, you believe that you’re the creation of a jealous God who later decided that He liked one group of people best and would help them to smite all others, then your view of humanity may not be any more uplifting. Both ideas have created a lot of unrest and general unhappiness in our world, because if we think that our own human nature is either a happy accident or a sinful creation, then how highly will we regard the lives of others?

Few of us escape the social conditioning – the indoctrination – that offers us two fundamental definitions of our nature and the nature of the universe. We can accept that we were created by sheer chance, and that millions of years of unfeeling, tooth-and-claw natural selection resulted in the formation of our consciousness, our very capacity to think and feel. Or, we can accept that we were created with divine intention, but with inherently sinful natures; and we’re surrounded by a tainted world that keeps tempting us to fall farther away from grace. Neither philosophy encourages us to view the life of self and other as sacred. Creationism or Darwinism: How about doing away with both?

It would be beneficial for us to either create new stories that honor the nobility and mystery of the human spirit or else admit that we just don’t know anything for certain about our origins. Our children, naturally inquisitive and creative as they are, can speculate for themselves and perhaps come up with more life-affirming explanations than the ones currently being offered to them. At least this way we’d be preserving some of the mystery and wonder of life for them.