Image Caption: Planetary nebula IC 1295 surrounding a dim and dying star. Credit: ESO
[ Watch the Video: Zooming In On The Planetary Nebula IC 1295 ]
Lee Rannals for redOrbit.com – Your Universe Online
A new image released by the European Space Observatory (ESO) shows the glowing green planetary nebula IC 1295.
The new pictures taken by the Very Large Telescope (VLT) shows the nebula surrounding a dim and dying star located about 3300 light-years away in the constellation of Scutum (The Shield).
“It has the unusual feature of being surrounded by multiple shells that make it resemble a micro-organism seen under a microscope, with many layers corresponding to the membranes of a cell,” according to an ESO statement.
The glowing green bubble seen in the image is made out of gas that used to be the star’s atmosphere. The gas has been expelled by unstable fusion reactions in the star’s core that generated sudden releases of energy. It contains ultraviolet radiation, which gives it its glow.
In the center of the image, you can see the burned-out remnant of the star’s core as a bright blue-white spot at the heart of the nebula. The central star will become a very faint white dwarf and slowly cool down over many billions of years.
Stars that have masses like the Sun and up to eight times that of the Sun will form planetary nebulae as they enter the final phase of their existence.
The name ‘planetary nebula’ has nothing to do with planets. It is actually a descriptive term applied to some early discoveries because of the visual similarity of these objects to the outer planets Uranus and Neptune. Early astronomers using older telescopes saw these far away planets as glowing gas.
ESO released another beautiful image of the bright star cluster NGC 6520 back in February. The image shows NGC 6520 alongside a strange dark cloud known as Barnard 86. These two objects sit inside millions of glowing stars in the brightest part of the Milky Way galaxy. Barnard 86 is a dark nebula known as a Bok globule. Although in the image it appears as if it was a break in the stars, the nebula is actually made up of small dust grains that block out starlight. Astronomers believe this nebula formed from the remnants of a molecular cloud that collapsed to form the nearby star cluster NGC 6520.
ESO’s VLT is the world’s most advanced visible-light astronomical observatory. The space observatory continues to provide scientists with unique views of the universe that exists beyond what conventional backyard telescopes pick up.

Source: Lee Rannals for redOrbit.com - Your Universe Online
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cube robots can self-assemble

PTI | Oct 7, 2013, 05.27 AM IST
READ MORE Massachusetts Institute of Technology|cube robots|CSAIL
WASHINGTON: Scientists have developed new Terminator-style cube-shaped robots that can leap through the air, jump on top of each other and assemble together to form arbitrary shapes. A more refined version of the robots could temporarily repair bridges or buildings during emergencies, or assemble into different types of furniture or heavy equipment as needed, researchers say.

Developed by scientists from the Massachusetts Institute of Technology (MIT), the robots, known as M-Blocks , are cubes with no external moving parts. They are able to climb over and around one another, roll across the ground, and even move while suspended upside down from metallic surfaces, researchers said. Inside each robot is a flywheel that can reach speeds of 20,000 revolutions per minute; when the flywheel is braked, it imparts its angular momentum to the cube. On each edge of an M-Block , and on every face, are cleverly arranged permanent magnets that allow any two cubes to attach to each other.

"It's one of these things that the (modular-robotics ) community has been trying to do for a long time," said Daniela Rus, a professor of electrical engineering and computer science and director of MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL). "We just needed a creative insight and somebody who was passionate enough to keep coming at it — despite being discouraged," she said.

As with any modular-robot system, the hope is that the modules can be miniaturized— the ultimate aim of most such research is hordes of swarming 'microbots' that can self-assemble , like the "liquid steel" androids in the movie 'Terminator II' . MIT researchers are now building an army of 100 cubes, each of which can move in any direction, and designing algorithms to guide them. "We want hundreds of cubes, scattered randomly across the floor, to be able to identify each other, coalesce, and autonomously transform into a chair, or a ladder, or a desk, on demand ," said John Romanishin of CSAIL.
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Sun set for 11-year magnetic pole flip

, TNN | Oct 7, 2013, 05.18 AM IST
READ MORE Stanford University|Satellite|Magnetic fields
NEW DELHI: A special event is about to occur in our sun, and it could impact our lives. The magnetic poles of the sun — which are like the ends of a giant bar magnet — are about to flip, that is, the polar north will become the polar south and vice versa. According to scientists at the Wilcox Solar Observatory at Stanford University , the sun could be barely two to three months away from this magnetic field reversal. The change is periodic, taking place once every 11 years or so.

The flip also corresponds with peak activity during the 11-year solar cycle. This is when sunspots — intense magnetic field flu ctuations that appear as dark spots on the solar surface — are highest in number. "When the number of sunspots is highest, a time known as the solar maximum, the sun's large-scale dipole magnetic field starts reversing. This reversal is akin to sun's magnetic poles flipping. It's almost as if a giant magnet inside the sun was turned upside down," said Dibyendu Nandi, an a strop hysicist at Kolkata's Indian Institute of Science Education and Research.

Why does this flip take place? Nandi said that the periodic reversal was linked to the motion of plasma flows inside the sun. The flow of this hot, electrically-charged material tosses and turns one component of the magnetic field into another, eventually changing the sun's dipole field. "This process is technically known as the solar dynamo mechanism and can be studied using computer models which we do in our laboratories," Nandi said. Changes in the sun's magnetic field ripple through the solar system and beyond, a region known as the heliosphere. The weather in space is expected to be most hazardous in the next few months as the flip begins to take place, Nandi said.

"The chances of solar magnetic storms occurring are also high. These storms carry a vast amount of charged particles and magnetic fields through interplanetary space and can pose a threat to satellite operations , telecommunications , air traffic on polar routes and power grids in countries at high latitudes ," the scientist said.

Scientists are watching the event closely to fully understand the changes that take place. It's also of special interest because the current solar cycle — the 24th since 1755, when sunspot activity began to be recorded — is one of the weakest in 100 years. A strong solar magnetic field also acts as a shield against cosmic rays coming from outer space. "Due to the current weak cycle, we have been recording high cosmic ray influx since 2009," said B N Dwivedi of IIT-BHU.

In India, solar magnetic fields are being observed from the solar observatories at Udaipur and Kodaikanal. Then there are theoretical astrophysicists such as Nandi who build computer models to study and predict solar behaviour.
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