(Press-News.org) Livermore - New results from the NASA NuSTAR telescope show that a supernova close to our galaxy experienced a single-sided explosion.
A team of scientists including Lawrence Livermore National Laboratory researchers found that X-ray emissions taken with the Nuclear Spectroscopic Telescope Array (NuSTAR) show that the Supernova 1987A explosion was highly asymmetric. The results appear in the May 8 edition of the journal, Science.
NuSTAR observations, including those of 1987A, provide strong and compelling observational evidence that supernovae are not symmetric.
Supernova 1987A in the Large Magellanic Cloud provides a unique opportunity to study a nearby (170,000 light years) core collapse supernova explosion (CCSN) and its subsequent evolution into a supernova remnant.
SN1987A has validated some basic scientific assumptions about CCSNs. A neutrino flash confirmed that the overall explosion is driven by the collapse of the central core to a neutron star. Direct gamma-ray detection of cobalt isotopes and the correlation between the exponential decay of the optical light curve and lifetime of these isotopes confirmed that the light curve is powered by radioactive decay.
"Even with all we have previously learned about SN1987A, NuSTAR has taught us some new things," said Michael Pivovaroff, one of the LLNL scientists and co-author of the paper. "Our observations confirmed the tremendous speeds at which the exploding material is moving and helped us constrain geometrical models that show just how lopsided the supernova explosion was."
In core-collapse supernovae, an isotope of titanium (?? Ti) is produced in the innermost ejecta, in the layer of material directly on top of the newly formed remnant. The radioactive decay of this isotope provides a direct probe of the supernova engine. NuSTAR measurements confirm that heavy elements are moving at speeds of about 3,000 kilometers per second, several times higher than expected from spherically symmetric models.
There has been growing evidence for asymmetries in supernovae explosions over the past decades, including in SN1987A from the extensive evidence for mixing and polarized optical emission. NuSTAR observations of the spatial distribution of ?? Ti in the Cassiopeia A supernova remnant shows direct evidence of asymmetry. And these observations indicate even more asymmetry for SN1987A.
Subsequent X-ray observations have revealed expanding, brightening ejecta (a supernova remnant). To date, there is no evidence yet for a compact central object that formed form the core of the exploding star.
NuSTAR observed SN1987A for multiple periods between September 2012 and July 2014 with a total exposure of 2,283 kiloseconds (a kilosecond is 1,000 seconds).
NuSTAR, a NASA Explorer-class mission launched in June 2012, is uniquely designed to detect the highest-energy X-ray light in great detail. For Livermore, the predecessor to NuSTAR was a balloon-borne instrument known as HEFT (the High Energy Focusing Telescope) that was funded, in part, by a Laboratory Directed Research and Development investment beginning in 2001. NuSTAR takes HEFT's X-ray focusing abilities and sends them beyond Earth's atmosphere on a satellite. The optics principles and the fabrication approach for NuSTAR are based on those developed under the HEFT project.
The Lab's contribution to NuSTAR has been recognized by NASA in recent awards. Pivovaroff and LLNL physicist Julia Vogel are part of the NuSTAR science team that received a group award in September 2014 "for exceptional achievement in executing the NuSTAR science program leading to groundbreaking discoveries in high energy astrophysics." They, along with Lab engineer Todd Decker and postdoc Nicolai Brejnholt, also were part of the NuSTAR instrument team that received a group award in July 2013 "for outstanding performance in the design and successful implementation of the first space-borne high energy X-ray focusing telescope."
INFORMATION:
Other collaborators on this Science publication include University of California, Berkeley, California Institute of Technology, Los Alamos National Laboratory. North Carolina State University, McGill University, Université de Toulouse, CNRS, Technical University of Denmark, Agenzia Spaziale Italiana, Columbia University, RIKEN, SLAC National Accelerator Laboratory, Osservatorio Astronomico di Roma, Jet Propulsion Laboratory and NASA Goddard Space Flight Center.
Founded in 1952, Lawrence Livermore National Laboratory provides solutions to our nation's most important national security challenges through innovative science, engineering and technology. Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC for the U.S. Department of Energy's National Nuclear Security Administration.
El Salvador, Niger, and Pakistan are performing better in improving water and sanitation for their citizens than industrial giants like Russia and Brazil according to the new WaSH Performance Index developed by The Water Institute at the University of North Carolina at Chapel Hill's Gillings School of Global Public Health. The new index to be released Friday, May 8 during a live webcast shows which countries are leaders in improving access to water and sanitation for their citizens. Sub-Saharan Africa countries including Mali, South Africa, and Ethiopia are also among the ...
(MEMPHIS, Tenn. -- May 8, 2015) St. Jude Children's Research Hospital scientists have gained ground toward developing more targeted therapies for the most common childhood brain tumor. The findings appear today in the Journal of Molecular Biology.
The findings involve the DDX3X gene. In 2012, the St. Jude Children's Research Hospital -- Washington University Pediatric Cancer Genome Project highlighted DDX3X as a promising focus for efforts to develop targeted therapies against medulloblastoma. Such treatments target the genetic mistakes that give rise to the brain tumor's ...
PITTSBURGH -- Scientists have been manipulating genes for a while. The University of Pittsburgh's Alexander Deiters just found a way to control the process with higher precision.
By using light.
Deiters and his group are the first to achieve this. The resulting paper was recently published in the Journal of the American Chemical Society.
Since 2013, scientists have used a gene-editing tool called CRISPR/Cas9. The method employs a bacterially derived protein (Cas9) and a synthetic guide RNA to induce a double-strand break at a specific location in the genome. This ...
Object recognition -- determining what objects are where in a digital image -- is a central research topic in computer vision.
But a person looking at an image will spontaneously make a higher-level judgment about the scene as whole: It's a kitchen, or a campsite, or a conference room. Among computer science researchers, the problem known as "scene recognition" has received relatively little attention.
Last December, at the Annual Conference on Neural Information Processing Systems, MIT researchers announced the compilation of the world's largest database of images ...
The Philippines warning center has raised a #2 warning for its citizens in the Luzon province of Catanduanes. This warning indicates, among other things, that the tropical cyclone will affect the locality and that winds of greater than 100 kph up to 185 kph (62 to 114 mph) may be expected in at least 18 hours.
Philippines know the storm as Dodong and have also raised warning #1 for the areas of Luzon provinces of Sorsogon. Albay, Camarines Norte, Camarines Sur, Quezon, Polillo Island, Aurora, Quirino, Isabela and the Visayas provinces of Northern and Eastern Samar.
Warning ...
Forecasters expect Tropical Depression 07W which is riding behind Typhoon Noul to intensify to typhoon strength within the next five days. Currently 07W is located 298 miles southeast of Pohnopei, one of the Federated States of Micronesia. It is moving at a slow 5 knots on a east northeast trajectory with maximum sustained winds of 30 knots gusting to 40 (18 to 24 mph). Maximum wave height is 11 feet. 07W is moving east, but will turn round to a northwesterly course.
A tropical storm WARNING is in force for Kosrae, Pingelap and Mokil in Pohnpei State. A tropical storm ...
For the last decade, scientists have deployed increasingly capable underwater robots to map and monitor pockets of the ocean to track the health of fisheries, and survey marine habitats and species. In general, such robots are effective at carrying out low-level tasks, specifically assigned to them by human engineers -- a tedious and time-consuming process for the engineers.
When deploying autonomous underwater vehicles (AUVs), much of an engineer's time is spent writing scripts, or low-level commands, in order to direct a robot to carry out a mission plan. Now a new ...
The EU-funded MycoSynVac project combines gene engineering and biotechnology to design a novel veterinary vaccine chassis based on the bacterium Mycoplasma pneumoniae.
By combining their systems biology expertise with cutting-edge synthetic biology methodologies, researchers will engineer a universal chassis, which will be free of virulence and optimized for fast growth in a serum-free medium.
This chassis will be used to create specific vaccines against two highly detrimental pathogens that are causing suffering in livestock animals and large financial losses to the ...
TAMPA, Fla. -- Androgen deprivation therapy (ADT) is a common treatment option for patients with advanced stage prostate cancer. But nearly 80 percent of patients who receive ADT report experiencing hot flashes during and after treatment. Moffitt Cancer Center researchers are working to determine what genetic factors and other characteristics might make prostate cancer patients more likely to experience hot flashes during and after therapy.
Cancer therapies often are associated with unwanted side effects. Some side effects can be so debilitating that patients decide ...
Mexico is undergoing a transformation: ranked as the second largest economy in Latin America, it's an increasingly dynamic middle-income country -- and its population is ageing rapidly. How will this relate to the burden of cancer?
Mexico is an interesting case study for the relationship between population ageing and cancer burden, according to new research published in ecancermedicalscience.
Researchers led by Dr Ajay Aggarwal of the Institute of Cancer Policy, Kings College London, UK, examined population data, cancer databases, and the research output of Mexican ...
