Geophysicists call it the new core paradox: They can’t quite explain how the ancient Earth could have sustained a magnetic field billions of years ago, as it was cooling from its fiery birth.
Now, two scientists have proposed two different ways to solve the paradox. Each relies on minerals crystallizing out of the molten Earth, a process that would have generated a magnetic field by churning the young planet’s core. The difference between the two explanations comes in which particular mineral does the crystallizing.
Silicon dioxide is the choice of Kei Hirose, a geophysicist at the Tokyo Institute of Technology who runs high-pressure experiments to simulate conditions deep within the Earth. “I’m very confident in this,” he reported on 17 December at a meeting of the American Geophysical Union in San Francisco, California.
But David Stevenson, a geophysicist at the California Institute of Technology in Pasadena, says that magnesium oxide — not silicon dioxide — is the key to solving the problem. In unpublished work, Stevenson proposes that magnesium oxide, settling out of the molten early Earth, could have set up the buoyancy differences that would drive an ancient geodynamo.
The core paradox arose in 2012, when several research teams reported that Earth’s core loses heat at a faster rate than once thought1, 2. More heat conducting away from the core means less heat available to churn the core’s liquid. That’s important because some studies suggest Earth could have had a magnetic field more than 4 billion years ago — just half a billion years after it coalesced from fiery debris swirling around the newborn Sun. “We need a dynamo more or less continuously,” Peter Driscoll, a geophysicist at the Carnegie Institution for Science in Washington DC, said at the meeting.
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The Martian movie is set 20 years in the future, but here at NASA we are already developing many of the technologies that appear in the film. The movie takes the work we’re doing and extends it into fiction set in the 2030s, when NASA astronauts are regularly traveling to Mars and living on the surface. Here are a few ways The Martian movie compares to what we’re really doing on our journey to Mars:
Analog Missions
MOVIE: In the film, Astronaut Mark Watney is stranded on the Red Planet.
REALITY: In preparation for sending humans to Mars, we have completed one of the most extensive isolation missions in Hawaii, known as HI-SEAS. The goal of this study was to see how isolation and the lack of privacy in a small group affects social aspects of would-be explorers. The most recent simulation was eight months long, and the next mission is planned to last a year.
Spaceport
MOVIE: The Martian movie launches astronauts on the Aries missions from a refurbished and state of the art space center.
REALITY: Currently, the Ground Systems Development and Operations’ primary objective is to prepare the center to process and launch the next-generation vehicles and spacecraft designed to achieve our goals for space exploration. We are not only working to develop new systems, but also refurbishing and upgrading infrastructure to meet future demands.
Deep Space Propulsion
MOVIE: In the film, the astronauts depart the Red Planet using a propulsion system know as the Mars Ascent Vehicle (MAV).
REALITY: We are currently developing the most powerful rocket we’ve ever built, our Space Launch System (SLS). Once complete, this system will enable astronauts to travel deeper into the solar system than ever before! The RS-25 engines that will be used on the SLS, were previously utilized as the main engine on our space shuttles. These engines have proven their reliability and are currently being refurbished with updated and improved technology for our journey to Mars.
Mission Control
MOVIE: In the movie, Mission Control operations support the Aries 3 crew.
REALITY: On our real journey to Mars, Mission Control in Houston will support our Orion spacecraft and the crew onboard as they travel into deep space.
Habitat
MOVIE: The artificial living habitat on Mars in The Martian movie is constructed of industrial canvas and contains an array of life support systems.
REALITY: The Human Exploration Research Analog (HERA), formerly known as the Deep Space Habitat, is a three-story module that was designed and created through a series of university competitions. Studies conducted in habitat mockups will allow us to evolve this technology to create a reliable structures for use on Mars.
Rover
MOVIE: The characters in the film are able to cruise around the Red Planet inside the Mars Decent Vehicle (MDV).
REALITY: We are currently developing a next generation vehicle for space exploration. Our Mars Exploration Vehicle (MEV) is designed to be flexible depending on the destination. It will have a pressurized cabin, ability to house two astronauts for up to 14 days and will be about the size of a pickup truck.
Harvest
MOVIE: Astronaut Mark Watney grows potatoes on Mars in The Martian movie.
REALITY: We’re already growing and harvesting lettuce on the International Space Station in preparation for deep space exploration. Growing fresh food in space will provide future pioneers with a sustainable food supplement, and could also be used for recreational gardening during deep space missions.
Spacesuit
MOVIE: The spacesuit worn by astronauts in the film allows them to work and function on the surface of Mars, while protecting them from the harsh environment.
REALITY: Prototypes of our Z-2 Exploration Suit are helping to develop the technologies astronauts will use to live and work on the the Martian surface. Technology advances in this next generation spacesuit would shorten preparation time, improve safety and boost astronaut capabilities during spacewalks and surface activities.
This month is filled with exciting celestial sights. Here are 10 targets you can view this month:
10. Unusual Sunset
During a sunset, our thick atmosphere absorbs most colors of sunlight, but red light is absorbed the least. Rarely, green flashes can be seen just above the sun’s edge. As the last sliver of the disk disappears below the horizon, be sure to watch its color.
9. Belt of Venus
Just after sunset, turn around and face east. A dark shadow will move up from the horizon and gradually cover the pinkish sky. This is caused from the Earth itself blocking the sunlight and is called the Earth Shadow or the Belt of Venus.
8. Crepuscular Rays
Also just after sunset, or before dawn, you may see rays of sunlight spread like a fan. These are called crepuscular rays and are formed when sunlight streams through gaps in the clouds or mountains.
7. Aurora Borealis
The northern lights, also known as the aurora borealis, are caused by collisions between gaseous particles in Earth’s atmosphere and charged particles released from the sun. The color of the lights can changed depending on the type of gas being struck by particles of solar wind. You can find out when and where to expect aurorae at the Space Weather Prediction Center.
6. Andromeda Galaxy
Did you now that The Andromeda Galaxy is one of the few you can actually see with your naked eye? In October, look nearly overhead after sunset to see it! This galaxy is more than twice the apparent width of the moon.
5. Moon Features
Nights in mid-October are excellent for viewing the features on the moon. Areas like the Sea of Tranquility and the site of the 1969 Apollo 11 landing will be visible.
4. A Comet
This month, the European Space Agency’s Rosetta mission target, a comet with a complicated name (Comet 67P Churyumov-Gerasimenko), is still bright enough for experienced astronomers to pick out in a dark sky. On October 9, you may be able to spot it in the east near the crescent moon and Venus.
3. Meteor Showers
There are multiple meteor showers this month. On the 9th: watch the faint, slow-moving Draconids. On the 10th: catch the slow, super-bright Taurids. And on the 21st: don’t’ miss the swift and bright Orionids from the dust of Comet Halley.
2. Three Close Planets
On October 28, you’ll find a tight grouping of Jupiter, Venus and Mars in the eastern sky before sunrise.
1. Zodiacal Light
The Zodiacal light is a faint triangular glow that can be seen from a dark sky after sunset or before sunrise. What you’re seeing is sunlight reflecting off dust grains that circle the sun in the inner solar system. These dust grains travel in the same plane as the moon and planets as they journey across our sky.
For more stargazing tools visit: Star Tool Box
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The work we do, and will continue in 2016, helps the United States maintain its world leadership in space exploration and scientific discovery. Here’s an overview of what we have planned for the coming year:
Our Journey to Mars
We’re developing the capabilities needed to send humans to an asteroid by 2025 and Mars in the 2030s. Mars is a rich destination for scientific discovery and robotic and human exploration as we expand our presence into the solar system. Its formation and evolution are comparable to Earth, helping us learn more about our own planet’s history and future.
Work and Research on the International Space Station
The International Space Station is a unique place – a convergence of science, technology and human innovation that demonstrates new technologies and makes research breakthroughs not possible on Earth. In 2016, we will continue our groundbreaking research on the orbiting laboratory.
Returning Human Spaceflight Launches to American Soil
Our Commercial Crew Program is working with the American aerospace industry as companies develop and operate a new generation of spacecraft and launch systems capable of carrying crews to low-Earth orbit and the International Space Station. Commercial transportation to and from the station will provide expanded utility, additional research time and broader opportunities of discovery on the orbiting laboratory.
Studying Our Earth Right Now
We use the vantage point of space to increase our understanding of our home planet, improve lives and safeguard our future. In 2016, we will continue to monitor Earth’s vital signs from land, air and space with a fleet of satellites and ambitious airborne and ground-based observation campaigns.
Fostering Groundbreaking Technology Development
Sustained investments in NASA technology advances our space exploration, science and aeronautics capabilities. Our technology development also supports the nation’s innovation economy by creating solutions that generate tangible benefits for life on earth. In 2016, we will continue to invest in the future of innovation.
Breakthroughs in Aeronautics
Thanks to our advancements in aeronautics, today’s aviation industry is better equipped than ever to safely and efficiently transport all those passengers to their destinations. In fact, every U.S. aircraft flying today and every U.S. air traffic control tower uses NASA-developed technology in some way. In 2016, we will continue making these breakthroughs in aeronautics.
Discoveries in Our Solar System and Beyond
This year we will continue exploring our solar system and beyond to unravel the mysteries of our universe. We are looking to answer key questions about our home planet, neighboring planets in our solar system and more!
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com
mark your calendars!!!
Tadashi was unaware of what Hiro was doing, since he had fallen back asleep in under five minutes. He couldn't feel any movement, though he would wake up to the slightest sounds. youneedsomeupgrades
hamada-tadashii
Hiro woke, rubbing his eyes and staring at the dark ceiling, slowly sitting up and dangling his feet off the bed. His eyes scanned the room searching for his sound asleep brother. As his eyes found him he tiredly stood out of bed and almost drunkly walked over to the bed, setting his hands on the bed, closing his eyes. “Dashi.. Tadashi, you awake?”
"I don't know who will read this. I guess someone will find it eventually. Maybe in a hundred years or so." -Mark Watney
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