Technology

The Source of The Sky’s X-Ray Glow

Main Point:

In findings that help astrophysicists understand our corner of the galaxy, an international research team has shown that the soft X-ray glow blanketing the sky comes from both inside and outside the solar system.

Published in:

Nature

Study Further:

The source of this “diffuse X-ray background” has been debated for the past 50 years. Does it originate from the solar wind colliding with interplanetary gases within our solar system? Or is it born further away, in the “local hot bubble” of gas that a supernova is believed to have left in our galactic neighborhood about ten million years ago?

The scientists found evidence that both mechanisms contribute, but the bulk of the X-rays come from the bubble. The solar wind, a stream of charged particles continuously emitted by the Sun, appears to be responsible for at most 40 percent of the radiation, according to new findings published in the journal Nature.

“The overarching science goal of our work is to try to answer questions like: What does the local astrophysical environment look like? And what is the environment in which the Sun was born?” said Susan Lepri, an associate professor of atmospheric, oceanic and space sciences in the University of Michigan College of Engineering.

“It’s part of trying to understand our place in the universe.” Read more…

Cosmic Grains Of Dust Formed In Supernova Explosion

Main Points:

There are billions of stars and planets in the universe. A star is a glowing sphere of gas, while planets like Earth are made up of solids. The planets are formed in dust clouds that swirled around a newly formed star. Dust grains are composed of elements like carbon, silicon, oxygen, iron, and magnesium. But where does the cosmic dust come from? New research from the Niels Bohr Institute at the University of Copenhagen and Aarhus University shows that not only can grains of dust form in gigantic supernova explosions, they can also survive the subsequent shockwaves they are exposed to. The results are published in the prestigious scientific journal Nature. Read more…

Vlt Clears up dusty mystery: New Observations reveal how Stardust forms around a Supernova

The dwarf galaxy UGC 5189A, site of the supernova SN 2010jl (annotated) (Credit: ESO)

Main Points:

A group of astronomers has been able to follow stardust being made in real time — during the aftermath of a supernova explosion. For the first time they show that these cosmic dust factories make their grains in a two-stage process, starting soon after the explosion, but continuing for years afterwards. The team used ESO’s Very Large Telescope (VLT) in northern Chile to analyze the light from the supernova SN 2010jl as it slowly faded. The new results are published online in the journal Nature on 9 July 2014.

Published in:

Nature

Study Further:

The origin of cosmic dust in galaxies is still a mystery [1]. Astronomers know that supernovae may be the primary source of dust, especially in the early universe, but it is still unclear how and where dust grains condense and grow. It is also unclear how they avoid destruction in the harsh environment of a star-forming galaxy. But now, observations using ESO’s VLT at the Paranal Observatory in northern Chile are lifting the veil for the first time. Read more…

A Hotspot for Powerful Cosmic Rays: Physicists a Step Closer to Finding Mysterious Sources

This map of the northern sky shows cosmic ray concentrations, with a “hotspot” with a disproportionate number of cosmic rays shown as the bright red and yellow spot, upper right. An international team of physicists using the University of Utah-operated Telescope Array near Delta, Utah, say their discovery of the hotspot should narrow the search for the mysterious source or sources of ultrahigh-energy cosmic rays, which carry more energy than any other known particle in the universe. (Photo Credit: K. Kawata, University of Tokyo Institute for Cosmic Ray Research.)

Main Points:

An observatory run by the University of Utah found a “hotspot” beneath the Big Dipper emitting a disproportionate number of the highest-energy cosmic rays. The discovery moves physics another step toward identifying the mysterious sources of the most energetic particles in the universe.

Journal:

Astrophysical Journal Letters

Study Further:

“This puts us closer to finding out the sources — but no cigar yet,” says University of Utah physicist Gordon Thomson, spokesman and co-principal investigator for the $25 million Telescope Array cosmic ray observatory west of Delta, Utah. It is the Northern Hemisphere’s largest cosmic ray detector.

“All we see is a blob in the sky, and inside this blob there is all sorts of stuff — various types of objects — that could be the source” of the powerful cosmic rays, he adds. “Now we know where to look.” Read more…

Young adults offer suggestions to improve Healthcare.gov

Main Point:

Researchers at the Perelman School of Medicine at the University of Pennsylvania interviewed a focus group of young adults to glean six suggestions for improving the Healthcare.gov website. The actionable improvements are discussed in an article being published in Annals of Internal Medicine.

Published in:

Annals of Internal Medicine

Study Further:

Thirty-three highly educated young adults aged 19 to 30 years in Philadelphia were asked about their impressions and their suggestions for improvements as they navigated the Healthcare.gov website during the first open enrollment period for the Affordable Care Act’s health insurance marketplace.

The young people offered six specific changes to improve the customer experience before the next enrollment period in November 2014. Among their suggestions, they asked for a glossary of terms; better descriptions of services that are included in their policies; and explanations of financial details and discounts.

The young people also suggested that the term “catastrophic” be replaced with a less negative or confusing word that better conveys the meaning of what is covered by catastrophic insurance.

According to the study authors, the young people’s suggestions show how small changes to the Healthcare.gov website could improve consumers’ understanding of a difficult process and also improve the usability of the website. Read more…