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<p>A backscattered electron image of the narrow opal rim surrounding a bright metallic mineral inclusion in meteorite found in Antarctica. The circular holes in this image are spots where laser analyses have been performed. Credit: H. Downes.</p>
Opal Discovered In Antarctic Meteorite
Planetary scientists have discovered pieces of opal in a meteorite found in Antarctica, a result that demonstrates that meteorites delivered water ice to asteroids early in the history of the solar system.
<p>Jupiter imaged using the VISIR instrument on the VLT<br />
In preparation for the imminent arrival of NASA’s Juno spacecraft in July 2016, astronomers used ESO’s Very Large Telescope to obtain spectacular new infrared images of Jupiter using the VISIR instrument. They are part of a campaign to create high-resolution maps of the giant planet to inform the work to be undertaken by Juno over the following months, helping astronomers to better understand the gas giant.<br />
<br />
This false-colour image was created by selecting and combining the best images obtained from many short VISIR exposures at a wavelength of 5 micrometres.<br />
<br />
Credit: ESO/L. Fletcher</p>
Glowing Jupiter Awaits Juno’s Arrival
Stunning new images of Jupiter at thermal infrared wavelengths give a glowing view of Juno’s target, a week ahead of the NASA mission’s arrival at the giant planet.

<p>Close-up of Sputnik Planum shows the slowly overturning cells of nitrogen ice. Boulders of water ice and methane debris (red) that have broken off hills surrounding the heart have collected at the boundaries of the cells. (Photo: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)</p>
Pluto’s ‘heart’ renews itself
Like a cosmic lava lamp, a large section of Pluto’s icy surface is renewed by a process called convection that replace older ices with fresher material.
<p>This illustration depicts the view from outside of a rapidly-accreting black hole. The bright light toward the center represents the super-heating of gas as it falls onto the black hole. Emanating from the center is a jet of accelerated particles moving near the speed of light. Surrounding the black hold is cool, clumpy gas and dust, which are falling inwards and will eventually join the material accreting onto the black hole.</p>

<p>Image: NRAO/AUI/NSF and Dana Berry/SkyWorks</p>
Supermassive Black Hole Feeding On Cold Gas Observed
For the first time, astronomers have detected billowy clouds of cold, clumpy gas streaming toward a black hole, at the center of a massive galaxy cluster.


Three New Element Names Proposed
The International Union of Pure and Applied Chemistry (IUPAC) opened a public comment period for the recommended names of elements 115, 117 and 118.
Super Quantum Simulator Entangles Hundreds of Ions
Physicists have “entangled” or linked together the properties of up to 219 beryllium ions (charged atoms) to create a quantum simulator.
Three Potentially Habitable Worlds Found
Astronomers have discovered three potentially habitable planets orbiting an ultracool dwarf star just 40 light-years from Earth.

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


Galileo at age 38.
Galileo Thermometers

Every substance has the property of 'mass', which is the basic physical presence of matter. Matter occupies space. A physical mass contained within a physical space produces the physical property of ' ...
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Protons and Neutrons are made of Up and Down quarks
Quarks

Quarks are the most fundamental particles that we know of. Both protons and neutrons are made of quarks. We know quarks exist; we have experimental proof. However nobody has been able to isolate them; ...
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Exercising In Space

What did astronaut Shannon Lucid like least about her six months on Space Station Mir? The daily exercise. 'It was just downright hard,' she wrote in Scientific American (May 1998). 'I had to put on a ...
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Science Quote

'As long as men are free to ask what they must; free to say what they think; free to think what they will; freedom can never be lost and science can never regress. '

J. Robert Oppenheimer
(1904-1966)


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