(Press-News.org) A recent and famous image from deep space marks the first time we've seen a forming planetary system, according to a study by U of T astrophysicists.
The team, led by Daniel Tamayo from the Centre for Planetary Science at U of T Scarborough and the Canadian Institute for Theoretical Astrophysics, found that circular gaps in a disk of dust and gas swirling around the young star HL Tau are in fact made by forming planets.
"HL Tau likely represents the first image taken of the initial locations of planets during their formation," says Tamayo. "This could be an enormous step forward in our ability to understand how planets form."
The image of HL Tau, taken in October 2014 by the state-of-the-art Atacama Large Millimeter/submillimeter Array (ALMA) located in Chile's Atacama Desert, sparked a flurry of scientific debate.
While those who observed the original image claimed that planets were most likely responsible for carving the gaps, some remained skeptical. It had been suggested that the gaps, especially the outer three, could not represent forming planets because they are so close together. It was argued that planets massive enough to carve such gaps should be scattered violently by the force of gravity and ejected from the system early on in its development.
But Tamayo's study is the first to suggest the gaps are evidence of planetary formation because the gaps are separated by amounts consistent with what's called a special resonant configuration. In other words, these planets avoid violent collisions with each other by having specific orbital periods where they miss each other, similar to how Pluto has avoided Neptune for billions of years despite the two orbits crossing one another.
Tamayo created two videos to show how HL Tau would appear in both resonant and non-resonant configurations.
The system can be much more stable in a resonant configuration and it's a natural state for planets in the HL Tau system to migrate to says Tamayo.
The HL Tau system is less than a million years old, about 17.9 billion kilometres in radius and resides 450 light years from Earth in the constellation Taurus.
Since young systems like HL Tau are shrouded by a thick cloud of gas and dust, they can't be observed using visible light. ALMA resolves that issue by using a series -- or an array -- of telescopes located 15 kilometres apart that use much longer wavelengths. The result is unprecedented access to high resolution images that Tamayo says will continue to revolutionize the study of planetary formation.
"We've discovered thousands of planets around other stars and a big surprise is that many of the orbits are much more elliptical than those found in our solar system" said Tamayo.
This and future ALMA discoveries may be the key to connecting these discovered planets to their original birth locations.
While the HL Tau system remains stable in its relatively young age, Tamayo says over billions of years it will act as a "ticking time bomb." Eventually the planets will scatter, ejecting some and leaving the remaining bodies on elliptical orbits like the ones found around older stars.
Our solar system does not seem to have undergone such a dramatic scattering event, notes Tamayo. Future observations could also go a long way in determining whether our solar system is typical or an oddity ideally suited for life.
"If further observations show these to be the typical starting conditions around other stars, it would reveal our solar system to be a remarkably special place," says Tamayo.
INFORMATION:
The findings are available online and will be published in the upcoming edition of Astrophysical Journal.
TORONTO, ON - Adults who experienced multiple incidents of childhood maltreatment were more than two times as likely to have trouble sleeping than their counterparts who were not maltreated during childhood, according to a new study from researchers at the University of Toronto, University of Ottawa, and Western University. The study appears online in the journal Sleep Medicine.
"We found a significant association between childhood maltreatment and difficulty sleeping later in life," says lead author Philip Baiden, a PhD Student at the University of Toronto's Factor-Inwentash ...
New technology developed at the Martinos Center for Biomedical Imaging at Massachusetts General Hospital (MGH) may extend the benefits of magnetic resonance imaging (MRI) to many patients whose access to MRI is currently limited. A redesign of the wire at the core of the leads that carry signals between implanted medical devices and their target structures significantly reduces the generation of heat that occurs when standard wires are exposed to the radiofrequency (RF) energy used in MRI. The novel system is described in a paper published in the online Nature journal Scientific ...
AMHERST, Mass. -- A revolution is coming in flexible electronic technologies as cheaper, more flexible, organic transistors come on the scene to replace expensive, rigid, silicone-based semiconductors, but not enough is known about how bending in these new thin-film electronic devices will affect their performance, say materials scientists at the University of Massachusetts Amherst.
Writing in the current issue of Nature Communications, polymer scientists Alejandro Briseño and Alfred Crosby at UMass Amherst, with their doctoral student Marcos Reyes-Martinez, now ...
ALEXANDRIA, VA, MAY 5, 2015 -- A statistical analysis of Job Corps data strongly suggests positive average effects on wages for individuals who participated in the federal job-training program.
Results of the analysis recently were included in an article in the Journal of Business & Economic Statistics (http://www.tandfonline.com/toc/ubes20/current), a professional journal published by the American Statistical Association . The study was conducted by Xuan Chen of Renmin University of China and Carlos A. Flores of California Polytechnic State University.
Job Corps is ...
DURHAM, N.C. -- A 12-week dose of an investigational three-drug hepatitis C combination cleared the virus in 93 percent of patients with liver cirrhosis who hadn't previously been treated, according to a study in the May 5, 2015, issue of The Journal of the American Medical Association.
Bristol-Myers Squibb funded the trial of the combination of three drugs -- daclatasvir, asunaprevir, and beclabuvir. None of the three drugs are FDA-approved, but daclatasvir is currently under review by the FDA. Duke Medicine researchers collaborated on the design and analysis of the ...
In two studies appearing in the May 5 issue of JAMA, patients with chronic hepatitis C virus (HCV) genotype 1 infection and with or without cirrhosis achieved high rates of sustained virologic response after 12 weeks of treatment with a combination of the direct-acting-antiviral drugs daclatasvir, asunaprevir, and beclabuvir.
Current estimates indicate that 130 million to 150 million people worldwide are chronically infected with HCV, resulting in up to 350,000 deaths per year. Of the 7 HCV genotypes identified, genotype 1 is the most prevalent worldwide, accounting for ...
Among patients with Clostridium difficile infection (CDI) who recovered following standard treatment with the antibiotics metronidazole or vancomycin, oral administration of spores of a strain of C difficile that does not produce toxins colonized the gastrointestinal tract and significantly reduced CDI recurrence, according to a study in the May 5 issue of JAMA.
C difficile is the cause of one of the most common and deadly health care-associated infections, linked to 29,000 U.S. deaths each year. Rates of CDI remain at unprecedented high levels in U.S. hospitals. Clinical ...
In what is a major step towards the prevention of recurring bouts of Clostridium difficile (Cdiff) infection, an international team led by Dale Gerding, MD, Hines Veterans Administration (VA) research physician and professor of Medicine at Loyola University Chicago Stritch School of Medicine, has shown that giving spores of non-toxic Cdiff by mouth is effective in stopping repeated bouts of Cdiff infection which occurs in 25-30 percent of patients who suffer an initial episode of diarrhea or colitis. The study is published in the May 5 issue of the Journal of American ...
For the first time, scientists have imaged thunder, visually capturing the sound waves created by artificially triggered lightning. Researchers from Southwest Research Institute (SwRI) are presenting the first images at a joint meeting of American and Canadian geophysical societies in Montreal, Canada, May 3-7.
"Lightning strikes the Earth more than 4 million times a day, yet the physics behind this violent process remain poorly understood," said Dr. Maher A. Dayeh, a research scientist in the SwRI Space Science and Engineering Division. "While we understand the general ...
Employing online training programs to teach psychotherapists how to use newer evidence-based treatments can be as successful as in-person instruction, according to a new RAND Corporation study.
Psychotherapy treatments can lag years behind what research has shown to be effective because there simply are not enough clinicians trained in new methods. That means that many people with mental health disorders are not getting the most effective nonpharmacological treatments, RAND researchers say.
For one such treatment, Interpersonal and Social Rhythm Therapy to treat bipolar ...
