Veil Nebula-NGC 6960

Veil Nebula-NGC 6960

Constellation:	Cygnus
Right ascension:	20h45m38.00s
Declination:	+30°42'30.0"
Apparent magnitude:	99.9

The Veil Nebula is a cloud of heated and ionized gas and dust in the constellation Cygnus. It constitutes the visible portions of the Cygnus Loop (radio source W78, or Sharpless 103), a large but relatively faint supernova remnant. The source supernova exploded some 5,000 to 8,000 years ago, and the remnants have since expanded to cover an area roughly 3 degrees in diameter (about 6 times the diameter, or 36 times the area, of the full moon). The distance to the nebula is not precisely known, but Far Ultraviolet Spectroscopic Explorer (FUSE) data supports a distance of about 1,470 light-years.

The Hubble Space Telescope captured several images of the nebula. The analysis of the emissions from the nebula indicate the presence of oxygen, sulfur, and hydrogen. This is also one of the largest, brightest features in the x-ray sky.

The nebula was discovered on 1784 September 5 by William Herschel. He described the western end of the nebula as "Extended; passes thro' 52 Cygni... near 2 degree in length", and described the eastern end as "Branching nebulosity... The following part divides into several streams uniting again towards the south."

When finely resolved, some parts of the image appear to be rope-like filaments. The standard explanation is that the shock waves are so thin, less than one part in 50,000 of the radius, that the shell is visible only when viewed exactly edge-on, giving the shell the appearance of a filament. Undulations in the surface of the shell lead to multiple filamentary images, which appear to be intertwined.

Even though the nebula has a relatively bright integrated magnitude of 7, it is spread over so large an area that the surface brightness is quite low, so the nebula is notorious among astronomers as being difficult to see. However, an observer can see the nebula clearly in a telescope using an OIII filter (a filter isolating the wavelength of light from doubly ionized oxygen), as almost all light from this nebula is emitted at this wavelength. An 8-inch (200 mm) telescope equipped with an OIII filter shows the delicate lacework apparent in photographs, and with an OIII filter almost any telescope could conceivably see this nebula. Some argue that it can be seen without any optical aid except an OIII filter held up to the eye.

A broad view of Cygnus loop/Veil
nebula in ultraviolet

The brighter segments of the nebula have the New General Catalog designations NGC 6960, 6974, 6979, 6992, and 6995. The easiest segment to find is 6960, which runs behind the naked eye star 52 Cygni. NGC 6992/5 are also relatively easy objects on the eastern side of the loop. NGC 6974 and NGC 6979 are visible as knots in an area of nebulosity along the northern rim. Pickering's Triangle is much fainter, and has no NGC number (though 6979 is occasionally used to refer to it). It was discovered photographically in 1904 byWilliamina Fleming (after the New General Catalogue was published), but credit went to Edward Charles Pickering, the director of her observatory, as was the custom of the day.

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Cat's Eye Nebula- NGC 6543

Constellation:	Draco
Right ascension:	17h58m33.42s
Declination:	+66°37'59.5"
Apparent magnitude:	9

The Cat's Eye Nebula or NGC 6543, is a planetary nebula in the constellation of Draco. Structurally, it is one of the most complex nebulae known, with high-resolution Hubble Space Telescope observations revealing remarkable structures such as knots, jets, bubbles and sinewy arc-like features. In the center of the Cat's Eye there is a bright and hot star; around 1000 years ago this star lost its outer envelope, producing the nebula.

It was discovered by William Herschel on February 15, 1786, and was the first planetary nebula whose spectrum was investigated by the English amateur astronomer William Huggins in 1864. The results of the latter investigation demonstrated for the first time that planetary nebulae consist of hot gases, but not stars. Currently the nebula has been observed across the full electromagnetic spectrum, from far-infrared to X-rays.

Modern studies reveal several mysteries. The intricacy of the structure may be caused in part by material ejected from a binarycentral star, but as yet, there is no direct evidence that the central star has a companion. Also, measurements of chemical abundances reveal a large discrepancy between measurements done by two different methods, the cause of which is uncertain. Hubble Telescope observations revealed a number of faint rings around the Eye, which are spherical shells ejected by the central star in the distant past. The exact mechanism of those ejections, however, is unclear.

Information : 

NGC 6543 is a well-studied planetary nebula. It is relatively bright at magnitude 8.1, and also has a high surface brightness. It is situated at right ascension 17h 58 m 33.4 s and declination +66°37'59″.^[4] Its high declination means it is easily observable from thenorthern hemisphere, where historically most large telescopes have been situated. NGC 6543 is situated almost exactly in the direction of the North Ecliptic Pole.

Composite image using optical images from the
 HSTand X-ray data from the Chandra X-ray Observatory

While the bright inner nebula is rather small—the major axis of the inner ellipse is 16.1 arcseconds, while the distance between the condensations is 24.7 arcseconds—it has an extended halo of matter that the progenitor star ejected during its red giant phase. This halo extends over a diameter of about 300 arcseconds (5 arcminutes). The cat's Eye nebula lies three thousand light-years from Earth.

Observations show that the main body of the nebula has a density of about 5,000 particles/cm³ and a temperature of about 7,000–9,000 K.^[7] The outer halo has a higher temperature of about 15,000 K and a much lower density.

In 1994, Hubble first revealed NGC 6543's surprisingly intricate structures, including concentric gas shells, jets of high-speed gas, and unusual shock-induced knots of gas.The central star of NGC 6543 is an O7 + [WR]–type star, with a temperature of approximately 80,000 K. It is approximately 10,000 times as luminous as the sun, and its radius is about 0.65 times the solar value. Spectroscopic analysis shows that the star is currently losing mass in a fast stellar wind at a rate of about 3.2×10⁻⁷ solar masses per year—about 20 trillion tons per second. The velocity of this wind is about 1900 km/s. Calculations indicate that the central star currently weighs just over one solar mass, but theoretical evolutionary calculations imply that it had an initial mass of about 5 solar masses.

An optical Image of the Nebula's Surrounding Halo

An optical Image of the Nebula's Surrounding Halo

Despite intensive study, the Cat's Eye Nebula still holds many mysteries. The concentric rings surrounding the inner nebula seem to have been ejected at intervals of from a few hundred to a few thousand years, a timescale which is rather difficult to explain. Thermal pulsations, which cause formation of planetary nebulae, are believed to take place at intervals of tens of thousands of years, while smaller surface pulsations are thought to occur at intervals of years to decades. A mechanism which would eject material over the timescales required to form the concentric rings in the Cat's Eye Nebula is not known yet.

The spectra of planetary nebulae consist of emission lines superimposed on a continuum. The emission lines may be formed either bycollisional excitation of ions in the nebula, or by recombination of electrons with ions. Collisionally excited lines are generally much stronger than recombination lines, and so have historically been used to determine abundances. However, recent studies have found that abundances derived from recombination lines seen in the spectrum of NGC 6543 are some three times higher than those derived from collisionally excited lines. The cause of this discrepancy is probably related to spatial temperature fluctuations inside the nebula.

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ESA’s Earth satellites are stars

SMOS tracks Hurricane Igor

The first three Earth Explorer satellites have surpassed their original objectives, demonstrating the versatility of these collaborative missions.The three missions in orbit are CryoSat, GOCE and SMOS. Over the past few years they have been providing new information on Earth’s cryosphere, gravity and soil moisture and ocean salinity, respectively, but there have also been several unexpected achievements.

Some of these were outlined at the Paris Air and Space Show this week by Johnny Johannessen, Director General of the Nansen Environmental and Remote Sensing Center and former Chairman of ESA’s Science Advisory Committee.


Mapping the Moho

Readings over Danube River delta

For More Visit : http://www.esa.int/Our_Activities/Observing_the_Earth/ESA_s_Earth_satellites_are_stars

Credit : ESA

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Hubble Telescope captures interacting galaxy pair-Arp 142

 Hubble Telescope captures interacting galaxy pair-Arp 142

The NASA/ESA Hubble Space Telescope has produced a vivid image of a pair of interacting galaxies known as Arp 142. When two galaxies stray too close to each other they begin to interact, causing spectacular changes in both objects. In some cases the two can merge-but in others, they are ripped apart.

Just below the centre of this image is the blue, twisted form of galaxy NGC 2936, one of the two interacting galaxies that form Arp 142 in the constellation of Hydra. Nicknamed "the Penguin" or "the Porpoise" by amateur astronomers, NGC 2936 used to be a standard spiral galaxy before being torn apart by the gravity of its cosmic companion.The remnants of its spiral structure can still be seen — the former galactic bulge now forms the "eye" of the penguin, around which it is still possible to see where the galaxy's pinwheeling arms once were. These disrupted arms now shape the cosmic bird's "body" as bright streaks of blue and red across the image. These streaks arch down towards NGC 2936's nearby companion, the elliptical galaxy NGC 2937, visible here as a bright white oval. The pair show an uncanny resemblance to a penguin safeguarding its egg.The effects of gravitational interaction between galaxies can be devastating. The Arp 142 pair are close enough together to interact violently, exchanging matter and causing havoc.In the upper part of the image are two bright stars, both of which lie in the foreground of the Arp 142 pair. One of these is surrounded by a trail of sparkling blue material, which is actually another galaxy. This galaxy is thought to be too far away to play a role in the interaction — the same is true of the galaxies peppered around the body of NGC 2936. In the background are the blue and red elongated shapes of many other galaxies, which lie at vast distances from us — but which can all be seen by the sharp eye of Hubble.This pair of galaxies is named after the American astronomer Halton Arp, the creator of the Atlas of Peculiar Galaxies, a catalogue of weirdly-shaped galaxies that was originally published in 1966. Arp compiled the catalogue in a bid to understand how galaxies evolved and changed shape over time, something he felt to be poorly understood. He chose his targets based on their strange appearances, but astronomers later realised that many of the objects in Arp's catalogue were in fact interacting and merging galaxies [1].This image is a combination of visible and infrared light, created from data gathered by the NASA/ESA Hubble Space Telescope Wide Field Planetary Camera 3 (WFC3).

Image credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

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This episode of the Hubblecast explores the violent world of galactic mergers, as shown by the cosmic duo Arp 142 in a stunning new image from the NASA/ESA Hubble Space Telescope.

Galaxies spend most of their life drifting through the cosmic expanse in isolation. But, every so often, two unfortunate galaxies stray a little too close to one another — as is the case with Arp 142. Showcased in a stunning new image from Hubble, these two galaxies uncannily resemble a penguin guarding its egg. The galaxies are in middle of a violent merger, with clouds of gas and dust colliding at breakneck speeds and triggering bursts of star formation.

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This video shows an animation of Hubble, before moving to zoom down through the telescope itself. Hubble is able to capture stunning images, providing an insight into some of the most turbulent events in our Universe.

Credit:

ESA/Hubble

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Microbial Creatures in Space

To monitor microbial growth and ensure a safe and healthy environment on the International Space Station, crew members take regular samples of air, surfaces, and water to be analyzed. Scientists' main focus is still to prevent microbes on the station, rather than to remediate. (NASA) 

The microbial ecosystems on the International Space Station are no different. Some microbes were inhabitants from the time the station was assembled. Some join each time a new crew member or payload arrives. People, their habits, their physiological reactions to their emotional states, and their physical environment are all variables that have the potential to continue to alter microbe systems on the space station. With the potential to affect future space exploration missions, researchers funded by NASA's Human Research Program plan to gather and analyze biological samples to study better the space station's Microbiome -- the ever-changing microbe environment that can be found on the space station and its inhabitants. 

Researchers are asking important questions: how might microbes aboard the station impact an astronaut living in space for a year or more? Could an extended period of spaceflight create an influx of disease-causing germs known as pathogens, or affect a crew member's ability to fight off a disease? What would be the potential effects to station hardware or its operation? Could it be a show-stopper for long-duration space travel? The old adage holds true: an ounce of prevention is worth a pound of cure. So, as plans continue toward exploring space further and longer, NASA researchers are looking for answers to these questions and others. 

NASA has a long history of studying the microorganisms that inhabit the closed-environments of spacecraft, such as the study of specific measurable characteristics called microbial biomarkers, which indicate the physiological state of organisms as they are spread among the crew members and their spacecraft environment. Until now, however, NASA has not conducted a systematic, comprehensive study using the latest molecular technology of the microbiome of the crew members or their environment. Among the station's microbes are pathogens that are introduced in a variety of ways. For example, humans naturally carry Staphylococcus aureus (more commonly known as "staph"), so it’s not surprising that this bacterium has been found on surfaces and in the air on the station where crew members live and work. Opportunistic pathogens (such as waterborne bacteria) could cause very serious, sometimes fatal infections. Crew members could serve as hosts, bringing pathogenic viruses aboard the station with them. 

Expedition Six Flight Engineer Don Pettit uses a chemical/microbial analysis bag to collect water samples from the Potable Water Heater in the Zvezda Service Module on the International Space Station. (NASA) 

"We spend a great deal of time and effort to prevent pathogens from getting aboard spacecraft," says Mark Ott, Ph.D., a microbiologist at NASA's Johnson Space Center, Houston. "So, we are definitely interested in possible changes in the types of organisms on spacecraft over time, which result from the crew's exposure to the spaceflight environment." 

A crew member's diminished immune system also can make infection more probable, so precautionary measures are put in place to protect them. Crew members receive medical exams before launch. Water and air aboard the station are filtered, and microbe levels (including on surfaces) are regularly sampled and monitored. Payloads are reviewed to ensure all biohazardous materials are adequately contained, and food lots are carefully analyzed before transport. The host-pathogen relationship aboard the station's environment is pivotal in the battle between health and disease; therefore, it is important that crew members maintain a healthy, robust immune system during their time aboard the space station. In the upcoming Microbiome study, a team of scientists led by Hernan Lorenzi, Ph.D., assistant professor at the J. Craig Venter Institute in Rockville, Md., plans to gather and analyze microbial air, surface and water samples from the station and saliva, blood, skin and perspiration samples from several crew members before, during and after their missions. Crew members will even provide gastrointestinal samples gathered during trips to the bathroom! 

Each bodily sample contains different collections of bacterial species that are likely to be affected by environmental factors associated with space travel. For instance, skin microbes are expected to be more susceptible to space radiation, while the composition of the gut and mouth microorganisms (or flora) may be more affected by changes in an astronaut's diet. Data from these collections will help scientists understand the status of the crew members' microbiome, its interaction with the unique environment of the space station and which environmental factors associated with space travel are most likely to alter the normal composition of the human microbiome. 

There also is intense study of the microbiome by the U.S. and other countries following the finding that it is linked to the state of health in different organs and tissues. Performing this study in the stressful environment of space will allow scientists to determine whether alterations in the crew’s microbiome are harmful to human health. 

For example, do microbes inhabiting the air of the space station end up being part of the astronauts' nose microbiome? And if so, do these newly acquired bacteria pose a potential risk to the crew members' health by displacing beneficial microbes from the nose? Answers gathered from this and other related studies are expected to provide bold new knowledge on the health effects of stress on out health on Earth, and will be critical for developing preventive treatments that diminish the chances of becoming sick during long stays in space. 

Impairment of immune function or introduction of disease from pathogens could have drastic consequences for the safety of the crew members and the success of a mission. The ability to assess the likelihood and consequences of changes in the microbiome due to extreme environments and the related health risks posed to humans also may benefit populations on Earth. This study may provide key factors to expanding our fragile horizon into space, while expanding the knowledge base for how the human body's micro biome functions.

Credit : NASA

IRIS Mission to Launch June 26

Image: 
The fully integrated spacecraft and science instrument for NASA's Interface Region Imaging Spectrograph (IRIS) mission is seen in a clean room at the Lockheed Martin Space Systems Sunnyvale, Calif. facility. The solar arrays are deployed in the configuration they will assume when in orbit. IRIS is scheduled to launch on June 26, 2013.

Understanding the interface between the photosphere and corona remains a fundamental challenge in solar and heliospheric science. The IRIS mission opens a window of discovery into this crucial region by tracing the flow of energy and plasma through the chromosphere and transition region into the corona using spectrometry and imaging. IRIS is designed to provide significant new information to increase our understanding of energy transport into the corona and solar wind and provide an archetype for all stellar atmospheres. The unique instrument capabilities, coupled with state of the art 3-D modeling, will fill a large gap in our knowledge of this dynamic region of the solar atmosphere. The mission will extend the scientific output of existing heliophysics spacecraft that follow the effects of energy release processes from the sun to Earth.

Image Credit: NASA/Lockheed Martin


NASA will launch its newest mission to watch the sun: the Interface Region Imaging Spectrograph, or IRIS on June 26. IRIS will show the lowest levels of the sun’s atmosphere, the interface region, in more detail than has even been observed before. 

This will help scientists understand how the energy dancing through this area helps power the sun’s million-degree upper atmosphere, the corona.

About IRIS : Understanding the interface between the photosphere and corona remains a fundamental challenge in solar and heliospheric science. The Interface Region Imaging Spectrograph (IRIS) mission opens a window of discovery into this crucial region by tracing the flow of energy and plasma through the chromosphere and transition region into the corona using spectrometry and imaging. IRIS is designed to provide significant new information to increase our understanding of energy transport into the corona and solar wind and provide an archetype for all stellar atmospheres. The unique instrument capabilities, coupled with state of the art 3-D modeling, will fill a large gap in our knowledge of this dynamic region of the solar atmosphere. The mission will extend the scientific output of existing heliophysics spacecraft that follow the effects of energy release processes from the sun to Earth.

IRIS Launch and Deploy Animation : Animation showing the launch of the IRIS satellite aboard an Orbital Sciences Pegasus XL rocket carried to space by Orbital's Stargazer L-1011 commercial transport aircraft modified to serve as the launch platform; the various Pegasus rocket stage separations and the eventual deployment of the IRIS satellite.

IRIS Science Overview :  NASA will launch its newest mission to watch the sun: the Interface Region Imaging Spectrograph, or IRIS. IRIS will show the lowest levels of the sun’s atmosphere, the interface region, in more detail than has even been observed before. This will help scientists understand how the energy dancing through this area helps power the sun’s million-degree upper atmosphere, the corona, as well as how this energy powers the solar wind constantly streaming off the sun to fill

Billion-Pixel View From Curiosity at Rocknest, White-Balanced

This image is a scaled-down version of a full-circle view which combined nearly 900 images taken by NASA's Curiosity Mars rover. The Full-Res TIFF and Full-Res JPEG provided in the top right legend are smaller resolution versions of the 1.3 billion pixel version for easier browser viewing and downloading. Viewers can explore the full-circle image with pan and zoom controls athttp://mars.nasa.gov/bp1/.

The view is centered toward the south, with north at both ends. It shows Curiosity at the "Rocknest" site where the rover scooped up samples of windblown dust and sand. Curiosity used three cameras to take the component images on several different days between Oct. 5 and Nov. 16, 2012.

This first NASA-produced gigapixel image from the surface of Mars is a mosaic using 850 frames from the telephoto camera of Curiosity's Mast Camera instrument, supplemented with 21 frames from the Mastcam's wider-angle camera and 25 black-and-white frames -- mostly of the rover itself -- from the Navigation Camera. It was produced by the Multiple-Mission Image Processing Laboratory (MIPL) at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

This version of the panorama has been white-balanced to show what the scene would look like under Earth lighting conditions, which is helpful in distinguishing and recognizing materials in the rocks and soil. A raw-color version is available at PIA16919. The view shows illumination effects from variations in the time of day for pieces of the mosaic. It also shows variations in the clarity of the atmosphere due to variable dustiness during the month while the images were acquired.

NASA's Mars Science Laboratory project is using Curiosity and the rover's 10 science instruments to investigate the environmental history within Gale Crater, a location where the project has found that conditions were long ago favorable for microbial life.

Malin Space Science Systems, San Diego, built and operates Curiosity's Mastcam. JPL, a division of the California Institute of Technology, Pasadena, manages the Mars Science Laboratory project for NASA's Science Mission Directorate in Washington and built the Navigation Camera and the rover.

Image Credit:

NASA/JPL-Caltech/MSSS

Fountain of Youth - Arp 194

Over the past 19 years Hubble has taken dozens of exotic pictures of galaxies going “bump in the night” as they collide with each other and have a variety of close encounters of the galactic kind. Just when you thought these interactions couldn’t look any stranger, this image of a trio of galaxies, called Arp 194, looks like one of the galaxies has sprung a leak. The bright blue streamer is really a stretched spiral arm full of newborn blue stars. This typically happens when two galaxies interact and gravitationally tug at each other.

Resembling a pair of owl eyes, the two nuclei of the colliding galaxies can be seen in the process of merging at the upper left. The bizarre blue bridge of material extending out from the northern component looks like it connects to a third galaxy but in reality the galaxy is in the background and not connected at all. Hubble’s sharp view allows astronomers to try and visually sort out what are foreground and background objects when galaxies, superficially, appear to overlap. 

The blue "fountain" is the most striking feature of this galaxy troupe and it contains complexes of super star clusters, that may have as many as dozens of individual young star clusters in them.  It formed as a result of the interactions among the galaxies in the northern component of Arp 194. The gravitational forces involved in a galaxy interaction can enhance the star formation rate and give rise to brilliant bursts of star formation in merging systems.

About this Object

Object Name:	Arp 194
Object Description:	Interacting Galaxy System
Position (J2000):	R.A. 11h 57m 55s.30 Dec. +36° 23' 20".00
Constellation:	Ursa Major
Distance:	600 million light-years or 184 megaparsecs
Dimensions:	This image is 76 arcseconds (220,000 light-years or 68,000 parsecs) wide.

About this Image

Image Credit:	NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
Release Date:	April 21, 2009
Color:	The image is a composite of separate exposures made by the WFPC2 instrument on the Hubble Space Telescope. Three filters were used to sample broad wavelength ranges and one filter was used to sample narrowband emission. The color results from assigning different hues (colors) to each monochromatic image. In this case, the assigned colors are: F814W (I) red F606W (V) green F450W (B) blue

Image Credit:

NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

Release Date:

April 21, 2009

Color:

The image is a composite of separate exposures made by the WFPC2 instrument on the Hubble Space Telescope. Three filters were used to sample broad wavelength ranges and one filter was used to sample narrowband emission. The color results from assigning different hues (colors) to each monochromatic image. In this case, the assigned colors are:

F814W (I)	red
F606W (V)	green
F450W (B)	blue

F814W (I)

red

F606W (V)

green

F450W (B)

blue

Hubble's resolution shows clearly that the stream of material lies in front of the southern component of Arp 194, as evidenced by the dust that is silhouetted around the star cluster complexes.

The details of the interactions among the multiple galaxies that make up Arp 194 are complex. The system was most likely disrupted by a previous collision or close encounter. The shapes of all galaxies involved have been distorted by their gravitational interactions with one another.

Arp 194, located in the constellation Cepheus, resides approximately 600 million light years away from Earth. Arp 194 is one of thousands of interacting and merging galaxies known in our nearby Universe. These observations were taken in January of 2009 with the Wide Field Planetary Camera 2. Blue, green and red filters were composited together to form the rather picturesque image of a galaxy interaction.

This picture was issued to celebrate the 19th anniversary of the launch of the Hubble Space Telescope aboard the space shuttle Discovery in 1990. During the past 19 years Hubble has made more than 880,000 observations and snapped over 570,000 images of 29,000 celestial objects.

Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

Hubble image of MACS J0717 with mass overlay

Composite image of the massive galaxy cluster
 MACS J0717.5+3745 from NASA's Chandra X-ray
Observatory. Image size is roughly 7.7 million
 light years across.

 MACS J0717.5+3745 (MACS J0717 or MACS 0717 for short) is a large galaxy cluster located 5.4 billion light years away in the constellation Auriga,appearing in the MAssive Cluster Survey (MACS). 

The cluster was formed by four separate galaxy clusters that have been involved in a collision. This is the first time that this phenomenon has been observed. The repeated collisions in MACSJ0717 are caused by a 13-million-light-year-long stream of galaxies, gas, and dark matter, known as a filament, pouring into a region already full of matter. When two or more of the galaxy clusters collide, the hot gas in the interstellar medium slows down, but the galaxies, composed mostly of empty space, do not slow as fast. The speed and direction of each of the clusters involved in the collision can thus be approximated through examining the offset between the galaxies and the gas.

Near-infrared Hubble Space Telescope image of MACS J0717.5+3745.

This enormous image shows Hubble’s view of massive galaxy cluster MACS J0717.5+3745. The large field of view is a combination of 18 separate Hubble images.

Studying the distorting effects of gravity on light from background galaxies, a team of astronomers has uncovered the presence of a filament of dark matter extending from the core of the cluster. 

The location of the dark matter is revealed in a map of the mass in the cluster and surrounding region, shown here in blue. The filament visibly extends out and to the left of the cluster core.

Using additional observations from ground-based telescopes, the team was able to map the filament’s structure in three dimensions, the first time this has ever been done. The filament was discovered to extend back from the cluster core, meaning we are looking along it.

Credit: NASA, ESA, Harald Ebeling (University of Hawaii at Manoa) & Jean-Paul Kneib (LAM)

Stellar jets HH 47, HH 34 and HH 2

The glowing, clumpy streams of material shown in these NASA/ESA Hubble Space Telescope images are the signposts of star birth.

Ejected episodically by young stars like cannon salvos, the blobby material zips along at more than 700 000 kilometres per hour. The speedy jets are confined to narrow beams by the powerful stellar magnetic field. Called Herbig-Haro or HH objects, these outflows have a bumpy ride through space.

When fast-moving blobs collide with slower-moving gas, bow shocks arise as the material heats up. Bow shocks are glowing waves of material similar to waves produced by the bow of a ship ploughing through water.

In HH 2, at lower right, several bow shocks can be seen where several fast-moving clumps have bunched up like cars in a traffic jam. In HH 34, at lower left, a grouping of merged bow shocks reveals regions that brighten and fade over time as the heated material cools where the shocks intersect.

In HH 47, at top, the blobs of material look like a string of cars on a crowded motorway, which ends in a chain-reaction accident. The smash up creates the bow shock, left.

These images are part of a series of time-lapse movies astronomers have made showing the outflows’ motion over time. The movies were stitched together from images taken over a 14-year period by Hubble’s Wide Field Planetary Camera 2. Hubble followed the jets over three epochs: HH 2 from 1994, 1997, and 2007; HH 34 from 1994, 1998, and 2007; and HH 47 from 1994, 1999, and 2008.

The outflows are roughly 1350 light-years from Earth. HH 34 and HH 2 reside near the Orion Nebula, in the northern sky. HH 47 is located in the southern constellation of Vela.

Credit:

NASA, ESA, and P. Hartigan (Rice University)

China has launched manned spacecraft Shenzhou-10 successfully

China's has launched its latest manned spacecraft Shenzhou-10 successfully after it blasted off on a 15-day mission to dock with a space lab and to educate young people about science.
The 15 day mission will be highlighted by the docking to the Tiangong-1 unmanned space module, which was launched on September 29, 2011.

It is China's fifth manned space mission and its longest. The spacecraft was launched aboard a Long March 2F rocket and will transport the crew to the Tiangong 1, which functions as an experimental prototype for a much larger Chinese space station to be launched in 2020. The craft will spend 12 days docked with the Tiangong.

On the heels of Canadian astronaut Chris Hadfield's wildly popular YouTube videos from the International Space Station, the Chinese crew plans to deliver a series of talks to students from aboard the Tiangong.

The craft carried two men, mission commander Nie Haisheng and Zhang Xiaoguang, and China's second female astronaut, Wang Yaping.

President Xi Jinping was shown live on television wishing them well at the launch centre: "You have made Chinese people feel proud of ourselves. You have trained and prepared yourselves carefully and thoroughly, so I am confident in your completing the mission successfully. I wish you success and look forward to your triumphant return."

The space programme is a source of enormous national pride for China, reflecting its rapid economic and technological progress and ambition to rank among the world's leading nations.

China is hoping to join the United States and Russia as the only countries to send independently maintained space stations into orbit. It is already one of just three nations to have launched manned spacecraft on its own.

The space classrooms mark the boldest step so far to bring the military-backed program into the lives of ordinary Chinese and follows in the footsteps of NASA, which uses student outreach to inspire interest in space exploration and sustain support for its budgets.

Full moon falls on June 23, 2013

Source Earth Sky 

      What is a supermoon?That doesn’t sound very special, does it? In fact, the June 2013 full moon lines up much more closely with perigee – the moon’s closest point to Earth – than Nolle’s original definition. According to Guy Ottewell’s Astronomical Calendar 2013, the 2013 June full moon falls only 22 minutes after the moon reaches perigee, the moon’s closest point to Earth for this month and year. At perigee, the moon lies only 356,991 kilometers (221,824 miles) away. Two weeks later, on July 7, the moon will swing out to apogee – its farthest point for the month and year – at 406,490 kilometers (252,581 miles) distant.

Full moon falls on June 23, 2013 at 11:32 UTC (6:32 a.m. CDT in the U.S.). Thus, for many, the moon appears about equally full in the June 22 sky as it does on June 23. This full moon is not only the closest and largest full moon of the year. It also presents the moon’s closest encounter with Earth for all of 2013. The moon will not be so close again until August, 2014.

At United States’ time zones, that means the moon will turn full on June 23 at 7:32 a.m. EDT, 6:32 a.m. CDT, 5:32 a.m. MDT and 4:32 a.m. PDT.

We astronomers call this sort of close full moon a perigee full moon. The word perigeedescribes the moon’s closest point to Earth for a given month. Two years ago, when the closest and largest full moon fell on March 19, 2011, many used a term we’d never heard before: supermoon. Last year, we heard this term again to describe the year’s closest full moon on May 6, 2012. Now the term supermoon is being used a lot. Last month’s full moon – May 24-25, 2013 – was also a supermoon. But the June full moon is even more super! In other words, the time of full moon falls even closer to the time of perigee, the moon’s closest point to Earth. The crest of the moon’s full phase in June 2013, and perigee, fall within an hour of each other.

Astronomers say you can’t really tell the difference in size between a supermoon and any other full moon. Check out this size comparison from our friend Alec Jones in the UK.

The supermoon of March 19, 2011 (right), compared to an average moon of December 20, 2010 (left). Note the size difference. Image Credit: Marco Langbroek, the Netherlands, via Wikimedia Commons.

Moon closest to Earth

Year	Date	Distance
2011	March 19	356,575 km
2012	May 6	356,955 km
2013	June 23	356,991 km
2014	August 10	356,896 km
2015	September 28	356,877 km
2016	November 14	356,509 km

The almost-full supermoon rises over downtown Oakland on May 24, 2013. The moonrise was at 8:09 p.m. and the full moon occurred at 9:25 p.m. The moon will be about 17,000 miles closer to earth than it usually is. (Jane Tyska/Staff)

Day and night sides of Earth at instant of June 23 full moon

Day and night sides of Earth at instant of full moon (2013 June 23 at 11:32 Universal Time). In North America, the full moon is setting in the west at sunrise. From eastern Asia, it’s rising in the east at sunset. The full moon resides close tozenith – straight overhead – as seen from the Samoan islands in the central South Pacific Ocean. Image credit: Earth and Moon Viewer