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From KQED

White House Honors Two Techies for Making Programming Cool

Bay Area residents Carlos Bueno and Kimberly Bryant are helping to prepare kids to use programming concepts in daily life and work.

Tech Titans Join Forces on Internet Surveillance

More than 60 technology firms and other groups are urging the federal government to let companies disclose Patriot Act data requests.

LinkedIn Co-Founder Calls for New Workplace 'Alliance'

Known as "the startup whisperer" of Silicon Valley, Bay Area native and LinkedIn co-founder Reid Hoffman joins us to discuss his recent book, "The Alliance." In it, Hoffman writes about the new era of employee-employer relationships, and proposes a model that emphasizes transparency over empty promises of loyalty and job security.

Privacy and the Internet of Things

Everyday objects -- watches, refrigerators and thermostats to name a few -- are becoming increasingly connected to each other and to us. The promise of "the Internet of things" is that we will be more efficient, healthier and ultimately happier. But so far consumers are not convinced. Recent research by data privacy company Truste found that a mere 22 percent of consumers believe the benefits of smart devices outweigh the risks. What are your hopes and concerns about these objects of the future?

PBS NewsHour

Why the moon hits your eye like a big … lemon?

That's not Amore, that's a lemon. Photo by Flickr user Paolo Nespoli

That’s not amore, that’s a lemon. Photo by Flickr user Paolo Nespoli

Scientists have finally made lemonade out of the origins of our lemon-shaped moon.

While the moon may look, to quote crooner Dean Martin, like a big pizza pie — the real shape is a bit more similar to a lemon. To explain, a study published in the journal Nature says, one needs to go back to when the satellite first formed.

“This happened a long time ago, when the moon was not completely solid,” said Ian Garrick-Bethell, lead author of the study. “This was in the first 100 to 200 million years of lunar thermal evolution.”

The moon consisted initially of liquid, molten rock. As the rock began to cool and solidify, the process was not even; the thin outer crust hardened first and continued to float on the molten core. The moon, at that time, was spinning rapidly, its shape bulging at the equator similar to the same effect you see in a spinning water balloon. All the while, its close proximity to earth allowed tidal and gravitational forces to pull at the thin crust, further distorting it. As it began to move away from Earth and cool more completely, the odd shape “froze” in place.

Garrick-Bethell told Space.com that solving the lunar mystery can aid in future studies of gravitational effects on celestial objects. “Chipping away at this problem of the shape of the moon can give us insight into those types of fundamental geology problems,” he said.

The post Why the moon hits your eye like a big … lemon? appeared first on PBS NewsHour.

Watch asteroids pummel the Earth in its first 500 million years

An artist's concept of the early Earth, battered by asteroids. Frequent impacts exposed liquid magma on parts of
         the planet, and water on the surface elsewhere. Courtesy: Simone Marchi

An artist’s concept of the early Earth, battered by asteroids. Frequent impacts exposed liquid magma on parts of the planet, while leaving water on the surface intact. Courtesy: Simone Marchi

A 500-million-year long storm of asteroids pummeled the infant Earth soon after it was formed, scientists believe. The smaller asteroids were the length of 15 football fields. The big ones were the size of Maine.

These collisions, which occurred during the Hadean eon, 4 to 4.5 billion years ago, were crucial to the planet’s evolution and may have paved the way for life. Those 500 million years of intense asteroid activity make up approximately 10 percent of the Earth’s history, said Simone Marchi, a research fellow at the Southwest Research Institute in Boulder, Colorado.

“It’s not a negligible amount of time,” Marchi said. “It’s really a critical time for understanding the evolution of the Earth. Much of what we see today, including ourselves — that is, life — is due to that early evolution. It’s very important to understand what the conditions of the Earth were during that time.”

Marchi and his colleagues have just released a new model to show how those collisions shaped the planet during its first 500 million years. Their study appears in Thursday’s edition of the journal Nature.

An artist's animation of the early Earth and moon, battered by asteroids. Frequent impacts melted, mixed and churned
         the Earth's early mantle, and shaped the crust. Courtesy: Simone Marchi

An artist’s animation of the early Earth and moon, battered by asteroids. Frequent impacts melted, mixed and churned the Earth’s early mantle, shaping the crust. Courtesy: Simone Marchi

science-wednesday

Their model shows where and when thousands of asteroids struck the Earth, churning up hot magma under the newly-formed surface. That mixing and melting destroyed rocks from Earth’s infancy, Marchi said. The oldest rocks recovered on Earth are 3.8 billion years old, too young to answer questions on the timing or magnitude of the asteroid strikes. An ancient mineral called zircon is the only material on Earth that appears to have survived the asteroid storm, but it is scattered throughout younger rocks, Marchi said, leaving few answers on its own.

The model simulates all of those collisions over millennia, and shows scientists how the asteroids may have shaped the Earth’s crust.

“When you have a large collision, you basically dig a large hole in the ground, and that means mixing and melting of the rocks. The heat from the impact can melt rocks in the proximity of collision,” Marchi said. “Mixing, melting and burial of rocks must have been extremely important back then, and we need to understand how the crust formed.”

The young solar system was full of debris during the Hadean eon. To figure out when and how often asteroids hit Hadean Earth, Marchi and his colleagues studied the moon’s craters and rock composition. The moon preserved a better record of ancient collisions, but it still takes detective work, he said.

“You have craters on top of craters on the moon, so you have to decode the information written in there.”

This animation shows where asteroids likely struck Earth over time.

Each circle represents a surface area impacted by an asteroid strike on Earth between 3.5 and 4.5 billion years ago.
         Color coding shows the timing of the impacts. Courtesy: Simone Marchi

Each circle represents a surface area impacted by an asteroid strike on Earth between 3.5 and 4.5 billion years ago. Color coding shows the timing of the impacts.
Courtesy: Simone Marchi

Our planet was hit thousands of times by “small” space debris, approximately 9 miles wide, Marchi’s team found. But occasionally, supersized asteroids — asteroids larger than 300 miles wide — struck the Earth’s surface. Those large impacts would have vaporized the Earth’s oceans, filling the atmosphere with steam.

For perspective, the meteor that exploded over Chelyabinsk, Russia in 2013 was 65 feet wide. The asteroid that likely killed the dinosaurs was believed to be six miles wide.

Compared to the Hadean eon, we live in a quiet time, Marchi said. He thinks the plethora of asteroid strikes helped create the conditions for life. But how they did it is still a mystery, he said.

“The oldest traces for life on Earth have been found in old rocks — isotopic traces of life. Those rocks date to 3.9 billion years old,” Marchi said, not long after the Hadean asteroid activity. “Is that just a coincidence or is there a more profound link to what’s going on in the Hadean and the present? It’s a very difficult problem to address, and there’s a lot of work to be done in that regard. This paper is just a step toward that goal.”

The post Watch asteroids pummel the Earth in its first 500 million years appeared first on PBS NewsHour.

If there’s an Ebola vaccine that works on monkeys, then what about humans?

The CDC released this map of the 2014 Ebola Hemorrhagic Fever outbreak in Guinea, Liberia and Sierra Leone.

The CDC released this map of the 2014 Ebola Hemorrhagic Fever outbreak in Guinea, Liberia and Sierra Leone.

Tuesday’s death of Sheik Umar Khan, the doctor at the front lines of Sierra Leone’s battle against the worst Ebola outbreak in history, marks the latest person killed by the contagious, incurable disease that has devastated communities in Guinea, Liberia and Sierra Leone since February. At last official count, released July 23, 672 people have died from the virus.

Outbreaks like this one beg for a vaccine, especially given the fatality rate of the disease, which can be up to 90 percent, according to the World Health Organization. The virus has popped up sporadically since 1976, when the Zaire species of Ebola virus was first recognized in Africa.

According to a Scientific American Q and A of leading virologist Thomas Geisbert, progress on a vaccine is stalled. But he says there are three to five preventative vaccines that have proven to protect nonhuman primates against the fatal virus.

The University of Texas researcher says scientists are stuck in phase I trials in humans. He estimates we are anywhere from two to six years from being able to break ground on an effective vaccine:

“I hate to say this, but it really depends on financial support for the small companies that develop these vaccines. Human studies are expensive and require a lot of government dollars. With Ebola, there’s a small global market — there’s not a big incentive for a large pharmaceutical company to make an Ebola vaccine, so it’s going to require government funding.

In terms of potential, he gives the example of the VSV vaccine, which functions similarly to the rabies vaccine. But Geisbert explains that vaccines like this one require a booster. The catch in Africa, he notes, is that “you’re lucky to get someone into a clinic to be vaccinated once. It’s a trade-off — efficacy versus safety. That’s one of the biggest challenges.”

As shown by the CDC map above, Ebola treatment centers, laboratories and clinics are not necessarily easily accessible by all communities.

The post If there’s an Ebola vaccine that works on monkeys, then what about humans? appeared first on PBS NewsHour.

Mars Rover sets extraterrestrial distance record

NASA's Opportunity rover took an image of the 'Lunokhod 2' Crater on Mars. Image by NASA/JPL-Caltech/Cornell/Arizona
         State Univ.

NASA’s Opportunity rover took an image of the ‘Lunokhod 2′ Crater on Mars. Image by NASA/JPL-Caltech/Cornell/Arizona State Univ.

NASA’s Mars rover Opportunity has now traversed 25.01 miles on the surface of the Red Planet, setting a new record for off-Earth distance traveled.

The Exploration Rover rolled 157 feet on Sunday, bringing its odometer reading officially over 25 miles. The previous record for extraterrestrial land travel was set by the Soviet Union’s Lunokhod 2 rover that landed on the moon in 1973 and drove 24.2 miles.

Opportunity has been on Mars since January, 2004. If it can travel another 1.1 miles, it will reach an exploration point scientists have dubbed “Marathon Valley;” named for the 26.2 mile distance from where the rover landed.

Opportunity is not the only NASA rover currently exploring the Martian surface. Mars rover Curiosity landed in 2012 and is engaged in analyzing mineral and atmospheric data as well as providing NASA with thousands of photographs for study. Curiosity discovered evidence of ancient stream beds and fresh water deposits on the planet, leading researchers to believe Mars once possessed conditions suitable for life.

NASA says that the future and ongoing rover missions to Mars are part of gaining information and experience to prepare for a manned expedition to the planet in the 2030s.

Image by NASA/JPL-Caltech

Image by NASA/JPL-Caltech

The post Mars Rover sets extraterrestrial distance record appeared first on PBS NewsHour.