NASA has released the first picture of Jupiter taken since the Juno spacecraft went into orbit around the planet on July 4.

The picture was taken on July 10. Juno was 2.7 million miles from Jupiter at the time. The color image shows some of the atmospheric features of the planet, including the giant red spot. You can also see three of Jupiter's moons in the picture: Io, Europa and Ganymede.

The Senate is set to approve a bill intended to change the way police and health care workers treat people struggling with opioid addictions.

My husband and I once took great pleasure in preparing meals from scratch. We made pizza dough and sauce. We baked bread. We churned ice cream.

Then we became parents.

Now there are some weeks when pre-chopped veggies and a rotisserie chicken are the only things between us and five nights of Chipotle.

Parents are busy. For some of us, figuring out how to get dinner on the table is a daily struggle. So I reached out to food experts, parents and nutritionists for help. Here is some of their (and my) best advice for making weeknight meals happen.

"O Canada," the national anthem of our neighbors up north, comes in two official versions — English and French. They share a melody, but differ in meaning.

Let the record show: neither version of those lyrics contains the phrase "all lives matter."

But at the 2016 All-Star Game, the song got an unexpected edit.

At Petco Park in San Diego, one member of the Canadian singing group The Tenors — by himself, according to the other members of the group — revised the anthem.

School's out, and a lot of parents are getting through the long summer days with extra helpings of digital devices.

How should we feel about that?

Police in Baton Rouge say they have arrested three people who stole guns with the goal of killing police officers. They are still looking for a fourth suspect in the alleged plot, NPR's Greg Allen reports.

"Police say the thefts were at a Baton Rouge pawn shop early Saturday morning," Greg says. "One person was arrested at the scene. Since then, two others have been arrested and six of the eight stolen handguns have been recovered. Police are still looking for one other man."

A 13-year-old boy is among those arrested, Greg says.

Copyright 2016 NPR. To see more, visit http://www.npr.org/.

After an international tribunal invalidated Beijing's claims to the South China Sea, Chinese authorities have declared in no uncertain terms that they will be ignoring the ruling.

The Philippines brought the case to the Permanent Court of Arbitration in The Hague, objecting to China's claims to maritime rights in the disputed waters. The tribunal agreed that China had no legal authority to claim the waters and was infringing on the sovereign rights of the Philippines.

Donald Trump is firing back at Supreme Court Justice Ruth Bader Ginsburg after she disparaged him in several media interviews. He tweeted late Tuesday that she "has embarrassed all" with her "very dumb political statements" about the candidate. Trump ended his tweet with "Her mind is shot - resign!":

Donald Trump wrapped up his public tryout of potential vice presidential candidates in Indiana Tuesday night with Gov. Mike Pence giving the final audition.

The Indiana governor's stock as Trump's possible running mate is believed to be on the rise, with New Jersey Gov. Chris Christie and former House Speaker Newt Gingrich also atop the list. Sources tell NPR the presumptive GOP presidential nominee is close to making a decision, which he's widely expected to announce by Friday.

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Cosmic Rays: 100 Years Of Mystery

Jul 25, 2012
Originally published on August 1, 2012 12:02 pm

This August, physicists are celebrating the 100th anniversary of the discovery of cosmic rays, showers of particles raining down on us from outer space. Although much has been learned about the nature and composition of cosmic rays, many puzzling questions remain. No one knows what physical processes could possibly accelerate particles to energies millions of times higher than those reached at CERN's Large Hadron Collider, where the Higgs was recently discovered.

Apart from their mysterious acceleration mechanism, cosmic rays also have a very practical impact on our world, producing about 13 percent of the natural background radiation in our environment. Airline crews are exposed to roughly twice as much cosmic-ray radiation, astronauts to even more. They also have enough energy to interfere with and damage computer equipment, causing taking a toll on memory devices and CPUs. In the 1990s, a study from IBM estimated that computers experience about one cosmic-ray-induced error per 256 megabytes of RAM per month.

And then there is the issue of space travel: radiation exposure remains a serious barrier to longer manned expeditions.

In August 1912, the Austrian physicist Victor Hess flew in a balloon to altitudes of 5.3 km, measuring the flux of particles in the sky. The expectation was that the flux would decrease with altitude, precisely the opposite of what Hess found. The shocking conclusion was that particles were raining down on Earth from space.

In the following decades, cosmic rays became a great tool for exploring the fundamental building blocks of matter. Slowly, their composition was decoded: about 90 percent are protons, 9 percent are alpha particles (the nuclei of helium atoms) and 1 percent are electrons. A small fraction comes from nuclei produced soon after the Big Bang, most importantly lithium. When particles hit the upper atmosphere, they collide with molecules of nitrogen and oxygen, creating a true "cosmic ray shower" of other particles, a spectacular illustration of E=mc2, as the energy of motion of the incoming particles are transmuted into new particles with varying masses and energies.

Although the mechanisms for producing most cosmic rays are well-understood, little is known of what causes the very high energy ones. High energies imply that the culprit or culprits must be dramatic astrophysical events. Two candidates have been proposed: gigantic black holes that live at the center of galaxies (including our own Milky Way, which sports a hulking monster of about four million solar masses) or gamma ray bursts, the brightest electromagnetic events known to occur in the universe. Possible candidates for gamma ray bursts are the rapid collapse of a star as it becomes a neutron star or a black hole during a supernova event, or the collision of two neutron stars.

Recently, an experiment run by the University of Wisconsin, IceCube (South Pole Neutrino Observatory), has presented strong evidence against gamma ray bursts as the possible mechanism accelerating ultra-high-energy cosmic rays. The theory predicts that supernovae events are accompanied by extensive neutrino production. After surveying some 300 gamma-ray bursts, IceCube failed to detect a single neutrino. On the other hand, another massive experiment, the Pierre Auger Observatory situated in the Mendoza Province in Argentina and with a detection area the size of Rhode Island, has found a strong correlation between the highest-energy cosmic rays and nearby active galactic nuclei, that is, the center of galaxies where massive black holes are actively gobbling up stars and gases.

As we track down the sources of the highest energy cosmic rays and use them to learn about the most dramatic events occurring in the universe, we should celebrate them as bridges between us and the confines of outer space, reminding us of our deep connection with the cosmos.


You can keep up with more of what Marcelo is thinking on Facebook and Twitter @mgleiser.

Copyright 2012 National Public Radio. To see more, visit http://www.npr.org/.