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Charged Particles from Outer Space are causing Disturbance on Earth’s Electronic Devices.

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We may not realise it, but when cosmic rays travels through the Earth's atmosphere at a speed of light, they create millions of electrically charged particles that strike our body in every second. 

While harmless to living organisms, a small part of these particles carry enough energy to interfere with the operation of the microelectronic circuitry in our electronic devices and can alter individual bits of data stored in a memory. 

This is called a single event upset or SEU and the outcome of this event could be various, from freezing your smartphone's UI to bringing down a passenger jet plane.

"This is a really big problem, but it is mostly invisible to the public," said Bharat Bhuva, professor of electrical engineering at Vanderbilt University during the annual meeting of the American Association for the Advancement of Science. Bhuva is a member of Vanderbilt’s Radiation Effects Research Group, established in 1987 to study the effects of radiation on electronic systems.

Serious incidents happened due to SEUs
As pointed out by Bhuva, there have been a number of incidents that illustrate how serious this problem can be. For example, in 2003 a bit flip in an electronic voting machine in Belgium, added 4,096 extra votes to one candidate. The error was only detected because it gave the candidate more votes than were possible. 

In 2008, the avionics system of a Qantus passenger jet flying from Singapore to Perth suffered from a SEU that caused the autopilot to disengage. As a result, the aircraft dove 690 feet in only 23 seconds, injuring the passengers seriously enough to divert the aircraft to the nearest airstrip. 

There have been also a number of unexplained glitches in airline computers, some of which experts feel must have been caused by SEUs. In addition to that SEUs can also disturb the performance of consumer electronics like computers, smartphones etc.

So, what's the solution? 
Since it is difficult to know when and where these particles will strike, the malfunctions they cause are very difficult to characterise. As a result, determining the prevalence of SEUs is not easy or straightforward.

"When you have a single bit flip, it could have any number of causes. It could be a software bug or a hardware flaw, for example. The only way you can determine that it is a single-event upset is by eliminating all the other possible causes," professor Bhuva explained. 

However, there are ways to design computer chips to dramatically reduce their vulnerability. For example, manufactures can design the processors in triplicate formation, as the probability of a SEUs will occur in two of the circuits at the same time is vanishingly small. 

So if two circuits produce the same result it should be correct. That's the same trick NASA use in it's spacecraft computer systems to maximise it's reliability in space. The good news is that the semiconductor manufacturers are all very concerned about this problem and taking steps to solve it.


article reference:- Research News @Vanderbilt 
image source:- pixabay

The Flame Nebula NGC 2024.

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The Flame Nebula, known as NGC 2024 is an emission nebula lies 1500 light years from Earth in the constellation Orion. Although, it appears like a billowing fire but fire, the rapid acquisition of oxygen, is not what makes this Flame glow. 

Rather the bright star Alnitak, the easternmost star in the Belt of Orion, shines energetic ultraviolet light into the Flame that knocks electrons away from the clouds of hydrogen gas that reside there. Much of the glow results when the electrons and ionized hydrogen recombine. 

Additional dark gas and dust lies in front of the bright part of the nebula and this is what causes the dark network that appears in the center of the glowing gas. The Flame Nebula is part of the Orion Molecular Cloud Complex, a star-forming region that includes the famous Horsehead Nebula.

According to a new study, the stars at the center of NGC 2024 were about 200,000 years old while those on the outskirts were about 1.5 million years in age.

Image Credit: ESO/J. Emerson/VISTA. Acknowledgment: Cambridge Astronomical Survey Unit

Our Home Planet and it's Moon, as Seen Form Mars.

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From one of the most powerful spacecraft orbiting Mars, comes a new composite image taken by the Mars Reconnaissance Orbiter [MRO] shows how our home planet Earth and its Moon appear together when seen from the red planet.

Taken on November 20, 2016 by the High Resolution Imaging Science Experiment [HiRISE] camera on NASA's MRO, the photograph is constructed from the best image of Earth and the best image of the moon from four sets of images, which were acquired to calibrate HiRISE data. When the component images were taken, Mars was about 205 million kilometers [127 million miles] away from Earth.

In this image, the reddish feature near the middle of the face of Earth is Australia. Southeast Asia appears as the reddish area near the top, Antarctica is the bright blob at bottom-left. Other bright areas are clouds.

As NASA describes in it's Official website, the image combines two separate exposures. For presentation, the exposures were processed separately to optimize detail visible on both Earth and the moon. The moon is much darker than Earth and would barely be visible if shown at the same brightness scale as Earth. But the combined view retains the correct positions and sizes of the two bodies relative to each other. 

You may have noticed that, in the photograph both Earth and moon appear closer than they actually are because, the observation was planned for a time at which the moon was almost directly behind Earth, from Mars' point of view, to see the Earth-facing side of the moon. 

With HiRISE and five other instruments, the MRO has been investigating Mars since 2006. In 2007 HiRISE had also snapped a similar image, when Earth was 142 million kilometers [88 million miles] from Mars.
In this image, the west coast outline of South America could be seen at the lower right, but clouds are the dominant features.



article reference:- nasa.gov & jpl.nasa.gov
image credit:- nasa/jpl-caltech/univ. of arizona 

A Halloween Treat from Space, a Solar Jack-o-Lantern captured by SDO.

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An amazing image captured by NASA's Solar Dynamics Observatory [SDO] shows that even the Sun is getting into the Halloween spirit.

SDO snapped this photo on October 8th, 2014. In this image, solar flares have gathered to form what appears to be a spooky face on sun's surface. The active regions on sun appear brighter because those are the areas that emit more light and energy - markers of an intense and complex set of magnetic fields hovering in the sun’s atmosphere, the corona. 

This composite image blends two sets of extreme ultraviolet wavelengths at 171 and 193 angstroms, giving the sun that perfect Halloween-like appearance.



article reference:- nasa.gov
image credit: nasa/sdo

Landing of First Space Shuttle Mission

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On April 14, 1981, the rear wheels of the space shuttle orbiter Columbia touched down on Rogers dry lake at Edwards Air Force Base, NASA's Armstrong Flight Research Center (then Dryden Flight Research Center) in southern California, to successfully complete a stay in space of more than two days. Astronauts John W. Young, STS-1 commander, and Robert L. Crippen, pilot, were aboard the vehicle. The mission marked the first NASA flight to end with a wheeled landing and represented the beginning of a new age of spaceflight.

An area of the air base was set aside for public viewing of the landing, and crowds numbered well over 200,000 people, with some estimates as high as 300,000 visitors who flocked to the site. 

James Young, Chief Historian of the Air Force Flight Test Center at Edwards AFB, remembered the landing well. "You just had to be there to hear, even feel, the double crack of the sonic boom," Young said. "It was such a tremendous sense of excitement to see something never seen before, to witness such a historic event."


article reference:- nasa.gov
photo credit: nasa

A Space Spider Watches Over Young Stars.

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Nebulae are clouds of interstellar gas and dust where stars can form. In this infrared image from NASA's Spitzer space telescope and 2MASS [Two Micron All Sky Survey], a nebula known as 'The Spider', officially named as IC 417, glows in fluorescent green lights. 

The Spider, located about 10,000 light-years from Earth in the constellation Auriga, is clearly a site of star formation. It resides in the outer part of the Milky Way, almost exactly in the opposite direction from the galactic center. 


also read:- The Dark Nebula Dobashi 4173.


One of the largest clusters of young stars in the Spider can be seen easily in the image. Toward the right of center, against the black background of space, you can see a bright group of stars called Stock 8. 


The light from this cluster carves out a bowl in the nearby dust clouds, seen in the imageas green fluff. Along the sinuous tail in the center, and to the left, the groupings of red point sources clumped in the green are also young stars.


also read:- The Heart Nebula.


In this image, infrared wavelengths, which are invisible to the normal eye, have been assigned in visible colors. 




article reference:- nasa.gov
image credit:- NASA/JPL-Caltech/2MAS

At Last, Einstein's Gravitational Waves Have Been Found.

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Gravitational waves, the ripples in the fabric of space-time that Einstein predicted a hundred years ago, have been finally found. Scientists at the Laser Interferometer Gravitational-Wave Observatory [LIGO] a pair of observatories located in Livingston,Washington and Hanford,Louisiana confirmed that they have detected the warping of space-time generated by the collision of two black holes more than 1 billion light-years away from Earth.

Albert Einstein predicted the existence of gravitational waves in his general theory of relativity a century ago, and scientists have been attempting to detect them for last 50 years. Einstein predicted that if the gravity in an area was changed suddenly - by an huge celestial explosion, waves of gravitational energy would ripple across the Universe at high-speed, stretching and squeezing space as they travelled.

The gravitational waves were detected on September 14, 2015 by both of the Observatories. The detector in Livingston recorded the event 7 milliseconds before the detector in Hanford. Based on the observed signals, scientists estimate that the black holes for this event were about 29 and 36 times the mass of the sun, and the event took place 1.3 billion years ago. They also found that during this collision, 3 times the mass of the sun was converted into gravitational waves in a fraction of a second. 

When a pair of black holes orbits around each other, they lose energy through the emission of gravitational waves, causing them to gradually approach each other over billions of years, and then much more quickly in the final minutes. During the final fraction of a second, the two black holes collide into each other at nearly one-half the speed of light and form a single more massive black hole, converting a portion of the combined black holes’ mass to energy. This energy is emitted as a final strong burst of gravitational waves. 

It is these gravitational waves that LIGO has observed. This new discovery is the first observation of gravitational waves, made by measuring the tiny disturbances that the waves make in to the space and time as they pass through the earth.

At each observatory, the 2.5 mile[4-km] long L-shaped LIGO interferometer uses laser light split into two beams that travel back and forth down the arms [4 foot diameter tubes kept under a near-perfect vacuum]. The beams are used to monitor the distance between mirrors precisely positioned at the ends of the arms. According to Einstein’s theory, the distance between the mirrors will change by an infinitesimal amount when a gravitational wave passes by the detector. A change in the lengths of the arms smaller than one-ten-thousandth the diameter of a proton [10-19 meter] can be detected.

With this discovery - we humans are ready to start a new quest, the quest to explore the warped side of the universe, objects and phenomena that are made from warped space-time. 

articale reference:- ligo.caltech.edu

Monstrous Cloud Boomerang Back to our Galaxy.

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This composite image shows the size and location of the Smith Cloud on the sky. The cloud appears in false-color, radio wavelengths as observed by the Green Bank Telescope in West Virginia. The visible-light image of the background star field shows the cloud's location in the direction of the constellation Aquila.
What goes up must come down - it even applies to an immense cloud of hydrogen gas outside our Milky Way galaxy. According to Hubble Space Telescope astronomers, the invisible cloud is plummeting toward our galaxy at nearly 700,000 miles per hour.

Though hundreds of enormous, high-velocity gas clouds whiz around the outskirts of our galaxy, this particular hydrogen gas cloud known as 'Smith Cloud' is unique because its trajectory is well known. New observations suggest it was launched from the outer regions of the galactic disk, around 70 million years ago. The cloud was discovered in the early 1960s by doctoral astronomy student Gail Smith.

The cloud is on a return collision course and is expected to plow into the Milky Way's disk in about 30 million years. When it does, astronomers believe it will ignite a spectacular burst of star formation, perhaps providing enough gas to make 2 million suns.
This diagram shows the 100-million-year-long trajectory of the Smith Cloud as it arcs out of the plane of our Milky Way galaxy and then returns like a boomerang. Hubble Space Telescope measurements show that the cloud came out of a region near the edge of the galaxy's disk of stars 70 million years ago. The cloud is now stretched into the shape of a comet by gravity and gas pressure. Following a ballistic path, the cloud will fall back into the disk and trigger new star formation 30 million years from now.
"The cloud is an example of how the galaxy is changing with time," explained team leader Andrew Fox of the Space Telescope Science Institute in Baltimore, Maryland. "It's telling us that the Milky Way is a bubbling, very active place where gas can be thrown out of one part of the disk and then return back down into another."

"Our galaxy is recycling its gas through clouds, the Smith Cloud being one example, and will form stars in different places than before. Hubble's measurements of the Smith Cloud are helping us to visualize how active the disks of galaxies are," Fox said.

Astronomers have measured this comet-shaped region of gas to be 11,000 light-years long and 2,500 light-years across. If the cloud could be seen in visible light, it would span the sky with an apparent diameter 30 times greater than the size of the full moon.

Astronomers long thought that the Smith Cloud might be a failed, starless galaxy, or gas falling into the Milky Way from intergalactic space. If either of these scenarios proved true, the cloud would contain mainly hydrogen and helium, not the heavier elements made by stars. But if it came from within the galaxy, it would contain more of the elements found within our sun.

The team used Hubble to measure the Smith Cloud's chemical composition for the first time, to determine where it came from. They observed the ultraviolet light from the bright cores of three active galaxies that reside billions of light-years beyond the cloud. Using Hubble's Cosmic Origins Spectrograph, they measured how this light filters through the cloud.
Hubble's Cosmic Origins Spectrograph can measure how the light from distant background objects is affected as it passes through the cloud, yielding clues to the chemical composition of the cloud. Astronomers trace the cloud's origin to the disk of our Milky Way. Combined ultraviolet and radio observations correlate to the cloud's infall velocities, providing solid evidence that the spectral features link to the cloud's dynamics.
In particular, they looked for sulfur in the cloud which can absorb ultraviolet light. "By measuring sulfur, you can learn how enriched in sulfur atoms the cloud is compared to the sun," Fox explained. Sulfur is a good gauge of how many heavier elements reside in the cloud.

The astronomers found that the Smith Cloud is as rich in sulfur as the Milky Way's outer disk, a region about 40,000 light-years from the galaxy's center [about 15,000 light-years farther out than our sun and solar system]. This means that the Smith Cloud was enriched by material from stars. This would not happen if it were pristine hydrogen from outside the galaxy, or if it were the remnant of a failed galaxy devoid of stars. Instead, the cloud appears to have been ejected from within the Milky Way and is now boomeranging back.

Though this settles the mystery of the Smith Cloud's origin, it raises new questions: How did the cloud get to where it is now? What calamitous event could have catapulted it from the Milky Way's disk, and how did it remain intact? Could it be a region of dark matter, an invisible form of matter that passed through the disk and captured Milky Way gas? The answers may be found in future research.

image credit:- nasa/esa
articale reference:- hubblesite.org
 
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