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<p>Schematic view of a bubble implosion, which is an envisioned picture showing the whole main events integrated, i.e., laser illumination, hot electron spread, implosion, and proton flash. (credit/ M. Murakami)</p>
Laser-driven Implosion
Scientists have discovered a novel particle acceleration mechanism called ‘micro-bubble implosion’
<p>Owens Valley Solar Array (EOVSA)</p>
New Insights into Solar Flares
New insights into solar flares' explosive energy releases were released by the Owens Valley Solar Array (EOVSA)

<p>In this illustration, the grid in the background represents the computational lattice that theoretical physicists used to calculate a particle property known as nucleon axial coupling. This property determines how a W boson (white wavy line) interacts with one of the quarks in a neutron (large transparent sphere in foreground), emitting an electron (large arrow) and antineutrino (dotted arrow) in a process called beta decay. This process transforms the neutron into a proton (distant transparent sphere). (Credit: Evan Berkowitz/Jülich Research Center, Lawrence Livermore National Laboratory)</p>
Life and Death of a Neutron
Experiments that measure the lifetime of neutrons reveal a perplexing and unresolved discrepancy.
<p>Precision assembly and mechanical technician Ryan Wilkinson inspects MOMA during thermal vacuum testing at Goddard</p>

<p>Credits: NASA</p>
Looking for Signs Life on Mars
Scientists have created a tiny chemistry lab for a rover that will drill beneath the Martian surface looking for signs of past or present life.


Massive Black Hole Devours a Star
Scientist create new models of Tidal Disruption Events - rare, but extremely forceful events taking place in the center of galaxies.
Dark Matter Limit Established
Experimental results from the XENON1T dark matter detector limit the effective size of dark matter particles to 4.1X10-47 square centimeters.
Water is not the same as water
Researchers have succeeded in separating the two forms of water to show that they can exhibit different chemical reactivities.

Science Facts

The Brave and Cold Ulysses

by NASA Marshall Space Flight Center and ScienceIQ.com

An artist Deep space is cold. Very cold. That's a problem--especially if you're flying in an old spaceship. And your power supplies are waning. And the fuel lines could freeze at any moment. Oh, and by the way, you've got to keep flying for thirteen more years. It sounds like a science fiction thriller, but this is really happening to the spacecraft Ulysses. Ulysses was launched in 1990 on a five-year mission to study the sun. The craft gathered new data about the speed and direction of the solar wind. It discovered the 3D shape of the sun's magnetic field. It recorded solar flares on the sun, and super-solar flares from distant neutron stars. Ulysses even flew through the tail of comet Hyakutake, an unexpected encounter that delighted astronomers. The mission was supposed to end in 1995, but Ulysses was too successful to quit. NASA and the ESA have granted three extensions, most recently in Feb. 2004. Ulysses is scheduled to keep going until 2008, thirteen years longer than originally planned.

Ulysses' extended mission, as before, is to study the sun. But at the moment Ulysses is far from our star. It's having an encounter with Jupiter, studying the giant planet and its magnetic field. Sunlight out there is 25 times less intense than what we experience on Earth, and Ulysses is getting perilously cold. Back in the 1980's, when Ulysses was still on Earth and being assembled, mission planners knew that the spacecraft would have to endure some low temperatures. So they put dozens of heaters onboard, all powered by a Radioisotope Thermoelectric Generator, or

Fuel lines are critical to the mission. They deliver hydrazine propellant to the ship's eight thrusters. Every week or so, ground controllers fire the thrusters to keep Ulysses' radio antenna pointing toward Earth. The thrusters won't work if the hydrazine freezes. No thrusters means no communication. The mission would be lost. About eight meters of fuel line snake through the spaceship. Every twist and turn is a possible cold spot, a place where the hydrazine can begin to solidify. The temperature at any given point along the fuel lines is bewilderingly sensitive to what's going on elsewhere in the spacecraft. Turning on a scientific instrument



The Chandra Mission

NASA's Chandra X-ray Observatory, which was launched and deployed by Space Shuttle Columbia on July 23, 1999, is the most sophisticated X-ray observatory built to date. Chandra is designed to observe ...
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An X-ray image of the Sirius star system located 8.6 light years from Earth.
Binary and Multiple Star Systems

Stars, like people, are seldom found in isolation. More than 80% of all stars are members of multiple star systems containing two or more stars. Exactly how these systems are formed is not well unders ...
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Rainbow Ark
Your Own Personal Rainbow?

Did you know that no two people ever see the very same rainbow? It's true. Rainbows are formed when light enters a water droplet, reflects once inside the droplet, and is reflected back to our eyes ...
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Science Quote

'I want to know God's thoughts...the rest are details.'

Albert Einstein
(1879-1955)





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