Magnificent View of Spiral Galaxy Messier 77

The Spiral galaxy Messier 77, 47 million light-years away and found in the constellation of Cetus (The Sea Monster) is captured in its full glory by the European Southern Observatory.

ESO’s Very Large Telescope (VLT) has captured a magnificent face-on view of the barred spiral galaxy Messier 77. The image does justice to the galaxy’s beauty, showcasing its glittering arms criss-crossed with dust lanes — but it fails to betray Messier 77’s turbulent nature.

This picturesque spiral galaxy appears to be tranquil, but there is more to it than meets the eye. Messier 77 (also known as NGC 1068) is one of the closest active galaxies, which are some of the most energetic and spectacular objects in the Universe. Their nuclei are often bright enough to outshine the whole of the rest of the galaxy. Active galaxies are among the brightest objects in the Universe and emit light at most, if not all, wavelengths, from gamma rays and X-rays all the way to microwaves and radiowaves. Messier 77 is further classified as a Type II Seyfert galaxy, characterised by being particularly bright at infrared wavelengths.

Clean Dwarf Galaxy Help Chart Universe

The image above is of IC 1613, a dwarf galaxy that is found in the Cetus constellation.

IC 1613 is unique in that unlike other galaxies, this dwarf galaxy contains very little cosmic dust which allows a clearer exploration of what is inside it. Cosmic dust is made of various heavier elements, such as carbon and iron, as well as larger, grainier molecules. Not only does dust block out light, making dust-shrouded objects harder to see, it also preferentially scatters bluer light. As a result, cosmic dust makes objects appear redder when seen through telescopes than they are in reality. Astronomers can factor out this reddening when studying objects. Still, the less reddening, the more precise an observation is likely to be.

IC 1613 also contains two types of stars, Cepheid variables and RR Lyrae variables. These type of stars rhythmically pulsate, growing characteristically bigger and brighter at fixed intervals and are used to measure galactic distances.

Galaxies come in different sizes. Our galaxy, The Milky Way, is a regular sized galaxy which contains 200 to 400 billion stars. There are smaller galaxies like the dwarf galaxy which only has several billion stars inside it. Dwarf galaxies like IC 1613, are small and have been observed to be pulled toward and merge with nearby spiral galaxies.

The OmegaCam was used to capture the image above. The OmegaCAM is a 32-CCD, 256-million-pixel camera mounted on the 2.6-metre VLT Survey Telescope at Paranal Observatory in Chile.

ESO Studying Mysterious Dwarf Galaxy Formed After Cosmic Collision

The European Southern Observatory used its Very Large Telescope at the Paranal Observatory to take detailed images of NGC 5291. NGC 5291 is located in the constellation of Centaurus. NGC 5291 is an elliptical galaxy that collided with another galaxy over 360 million years ago.

As a result of the collision, a dwarf galaxy was also formed; NGC 5291N. Astronomers have particular interest with this dwarf galaxy because according to their data, NGC 5291N mysteriously contains no old stars.

Centered in the image above is NGC 5291. Also seen is the Seashell Galaxy (MCG-05-33-005), a comma-shaped galaxy which appears to leech off NGC 5291’s luminous core. On the right side of the image is NGC 5291N. The dwarf galaxy was observed using MUSE's integral field spectrography.

The MUSE observations revealed unexpected oxygen and hydrogen emission lines in the outskirts of NGC 5291N.

A dwarf galaxy is a small galaxy containing less stars than a regular galaxy. It is usually composed of up to several billion stars. A regular galaxy like the Milky Way has 200 to 400 billion stars. Since these dwarf galaxies are small, they have been observed to be pulled toward and merge with nearby spiral galaxies. The Milky Way is believed to be a result of a build up of several dwarf galaxies.

Image of Sculptor Dwarf Galaxy Captured By ESO

The Sculptor Dwarf Galaxy, pictured in this new image from the Wide Field Imager camera, installed on the 2.2-metre MPG/ESO telescope at ESO’s La Silla Observatory, is a close neighbour of our galaxy, the Milky Way. Despite their close proximity, both galaxies have very distinct histories and characters. This galaxy is much smaller and older than the Milky Way, making it a valuable subject for studying both star and galaxy formation in the early Universe. However, due to its faintness, studying this object is no easy task.

The Sculptor Dwarf Galaxy — also known as the Sculptor Dwarf Elliptical or the Sculptor Dwarf Spheroidal — is a dwarf spheroidal galaxy, and is one of the fourteen known satellite galaxies orbiting the Milky Way. This is not to be confused with the similarly named and much brighter Sculptor Galaxy which is located in the same constellation of Sculptor.

A dwarf galaxy is a small galaxy composed of up to several billion stars. A regular galaxy like the Milky Way has 200 to 400 billion stars. Since these dwarf galaxies are small, they have been observed to be pulled toward and merge with nearby spiral galaxies.

Studying How Galaxy Collisions Affect Star Production

The International Centre for Radio Astronomy Research (ICRAR) is studying the relationship between colliding galaxies and star formation.

Looking beyond the common belief, that star production is faster when two galaxies collide, scientists at ICRAR believe that this is only true if the two galaxies are of similar mass. They theorize that if one galaxy is more massive than the other, the smaller of the galaxies generate less stars while the other has an increase production of it.

They explain that the reason for the unequal production of stars from two galaxies of different mass is because the bigger galaxy strips away its smaller galaxy's gas from its gas clouds which is a primary component for star production.

Kilo-Degree Survey (KiDS) To Study Dark Matter

Using imaging from the European Southern Observatory's VLT Survey Telescope (VST) and its huge camera, the OmegaCAM, the Kilo-Degree Survey (KiDS) aims to study and understand the relationship between dark matter and galaxies.

Astronomers theorize that dark matter which comprises 85% of all matter in the universe is what holds galaxies together. Without dark matter, galaxies would fling themselves apart while they rotate. Dark matter keeps these galaxies together due to the constraining effect of gravity.

The best way to work out where the dark matter lies is through gravitational lensing — the distortion of the Universe's fabric by gravity, which deflects the light coming from distant galaxies far beyond the dark matter. By studying this effect it is possible to map out the places where gravity is strongest, and hence where the matter, including dark matter, resides.

The survey studies the distortion of light emitted from galaxies. This light bends as it passes through massive clumps of dark matter while reaching the Earth. From the gravitational lensing effect, these groups turn out to contain around 30 times more dark than visible matter.

The image above shows a group of galaxies mapped by KiDS. On the right side, the image shows the same area of sky as in the left, but with the invisible dark matter rendered in pink.

Link Discovered Between Supernova Explosion and Powerful Magnetic Field From Magnetar

La Silla and Paranal Observatories in Chile have found a connection between a very long-lasting burst of gamma rays and an unusually bright supernova explosion. Previous belief was that radioactive decay was the reason behind these kind of explosions. Latest findings show that this particular supernova explosion was triggered by decaying super-strong magnetic fields around a magnetar.

The discovery was aided by Gamma-Ray Burst Optical/Near-Infrared Detector (GROND) on the MPG/ESO 2.2-metre telescope at La Silla and also with the X-shooter instrument on the Very Large Telescope (VLT) at Paranal. GROND is an imaging instrument to investigate Gamma-Ray Burst Afterglows and other transients while the X-shooter is a three armed multi-wavelength, medium resolution spectrograph.

Magnetars are tiny neutron stars that spin hundreds of times per second and has a magnetic field much stronger than normal neutron stars (also known as radio pulsars). Magnetars are thought to develop magnetic field strengths that are 100 to 1000 times greater than those seen in pulsars. These objects are believed to be the strongest magnetised objects in the Universe.

This discovery marks the first time to link magnetars and supernovas.

Extremely Powerful Magnetic Field Detected At Edge of Supermassive Black Hole

A very powerful magnetic field has been detected at the edge of a supermassive black hole in the distant PKS 1830-211 galaxy.

The magnetic field is far more powerful than anything previously detected in the core of a galaxy.

Supermassive black hole are found at the center of almost all the galaxies and are a million times more massive than the Sun. These black holes accrete (come or bring together under the influence of gravitation) vast amounts of matter in the form of a disc. This matter is sucked in the black hole but some escape and are flung out into space at close to the speed of light as part of a jet of plasma.

This discovery can help astronomers understand the structure and formation of supermassive black holes and the the twin high-speed jets of plasma they frequently eject from their poles.

The artist's impression show accretion of matter forming a brilliant hot disk around the black hole. There are also often high-speed jets of material ejected at the black hole’s poles that can extend huge distances into space. Observations with ALMA have detected a very strong magnetic field close to the black hole at the base of the jets and this is probably involved in jet production and collimation.

Spheroid Galaxies Shut Down Star Formation From Inside Out

Astronomers have shown for the first time how star formation in “dead” galaxies sputtered out billions of years ago. ESO’s Very Large Telescope and the NASA/ESA Hubble Space Telescope have revealed that three billion years after the Big Bang, these galaxies still made stars on their outskirts, but no longer in their interiors. The quenching of star formation seems to have started in the cores of the galaxies and then spread to the outer parts. The results will be published in the 17 April 2015 issue of the journal Science.

Spheroid galaxies are elliptical shaped galaxies and are common in the Universe. The center of these galaxies are densely packed with stars; about then times more than in the Milky Way.

Observing 22 galaxies , spanning a range of masses, from an era about three billion years after the Big Bang, the researchers noted that the galaxies were still producing stars at the outskirts but not in the center. The Star formation in the bulging center slowed down and stopped starting at the center of the galaxies and spread outwards towards the edges.

Probing the Spiderweb Galaxy Cluster (MRC 1138-262) Yields Surprising Data

A galaxy cluster is composed of smaller galaxies held together by gravity. It is the largest object found in the Universe.

Using the APEX telescope, astronomers probed the Spiderweb Galaxy which is a galaxy cluster 10.6 billion light years away. Formed by smaller galaxies, the Spiderweb Galaxy (also known as MRC 1138-262) has been studied for twenty years. It has been observed that the object contains a supermassive black hole and is a powerful source of radio waves.

The data from the observation has surprised scientists with their discovery of the formation of the stars in the galaxy cluster taking place. They have noted that instead of the stars being formed from the filaments of the cluster, APEX data has shown that the star formation region is concentrated in one area and not even centered on the galaxy cluster itself.

The Spiderweb Galaxy contains a supermassive black hole and is a powerful source of radio waves — which is what led astronomers to notice it in the first place. The object has thick dust clouds which the LABOCA camera on the APEX telescope can see through.

Distant Galaxy Collision Imaged Through Gravitational Lensing

The European Southern observatory and with the help of other agencies, has imaged a galactic collission that happened when the Universe was half its age using gravitational lensing.

Using state of the art instruments from all around the world, on the ground and in space, ESO has imaged galaxy H-ATLAS J142935.3-002836 in collision with another galaxy.

With the help of gravitational lensing which uses Einstein's theory that light can be bent given enough mass, scientists were able to study objects which would not be visible otherwise and to directly compare local galaxies with much more remote ones, seen when the Universe was significantly younger.

The image above shows the foreground galaxy that is doing the lensing, which resembles how our home galaxy, the Milky Way, would appear if seen edge-on. But around this galaxy there is an almost complete ring — the smeared out image of a star-forming galaxy merger far beyond.

In his theory of general relativity, Einstein predicted that given enough mass, light does not travel in a straight line but will be bent in a similar way to light refracted by a normal lens.”

Gravitational lensing is done with the help of galaxies and galaxy clusters which provides the mass that deflects light from objects behind them due to their strong gravity. The magnifying properties of this effect allow astronomers to study these objects.

The collision of H-ATLAS J142935.3-002836 was gathered using three ESO telescopes, the ALMA, APEX and VISTA, and with assistance of other telescopes and surveys namely: NASA/ESA Hubble Space Telescope, the Gemini South telescope, the Keck-II telescope, the NASA Spitzer Space Telescope, the Jansky Very Large Array, CARMA, IRAM and SDSS and WISE.

Galaxy Eater NGC 1316 in the Fornax Constellation Captured By ESO Telescope

In the Fornax constellation, there are two galaxies that are close to one another; NGC 1316 and NGC 1317. These two are quite close to one another but have two opposing histories. NGC 1317 has a quiet and silent past while NGC 1316 is a turbulent one.

NGC 1316 which is about 60 million light years away from Earth, has shown signs that is has eaten up and swallowed other galaxies in the past and may be still doing it up to now. Faint dust trails and tidal tails left over from its feast surround the galaxy giving evidence of its violent background.

The image captured by the European Southern Observatory's MPG/ESO 2.2-metre telescope shows the two galaxies in close proximity to each other. The small spiral NGC 1317 has led an uneventful life, but NGC 1316 has engulfed several other galaxies in its violent history and shows the battle scars.

Solving the Mystery of the Formation of Supermassive Galaxies (SMG)

Three billion years after the Big Bang, super massive galaxies (SMG) formed which is a mystery to scientists since most massive galaxies took most of the history of the universe to take shape.

These old galaxies are no longer forming new stars. But the stars inside these galaxies are compacted in a very small area making the size of these SMGs around three times smaller than similar mass galaxies today. They also are not flattened like current spiral galaxies with a center but they are elliptical.

Researchers from the Niels Bohr Institute believe that they might have solved this mystery. They explain that these massive galaxies were formed by colliding galaxies that initiated star formation a few billion years after the Big Bang.

1 to 2 billion years after the Big Bang, they theorize that gas from early galaxies where driven into the center of the galaxy system which ignited to form new stars in the center making it compact. And because of the number of stars formed so quickly, the gas needed to form new stars are used up making it a dead galaxy.

In the image above, an extremely compact dead galaxy is compared to the size of the Milky Way. The two have about the same amounts of stars, which meant that the density of stars in the compact galaxies is more that 10 times higher than the stars in the Milky way.

Measuring the Universe To One Percent Accuracy With Baryon Oscillation Spectroscopic Survey (BOSS)

The Baryon Oscillation Spectroscopic Survey (BOSS) Collaboration announced that they have measured the scale of the Universe to an accuracy of one percent, using galaxies more than six billion light years away.

BOSS mapped the locations of 1.2 million galaxies to make the measurements. The new distance measurements were presented at the meeting of the American Astronomical Society by Harvard University astronomer Daniel Eisenstein, the director of the Sloan Digital Sky Survey (SDSS-III).

In the image, the gray spheres show the pattern of the Baryon Acoustic Oscillations (BAO) from the early Universe. Galaxies today have a slight tendency to align on the spheres -- the alignment is greatly exaggerated in this illustration. By comparing the size of the spheres (white line) to the predicted value, astronomers can determine to one-percent accuracy how far away the galaxies are. This concept allowed the scientists to arrive at their measurement of the size of the Universe.

The Baryon Oscillation Spectroscopic Survey is an astronomical survey that measures the rate of expansion of the universe using the spatial distribution of Luminous Red Galaxies (LRG) and quasars. It is one of four components of the Sloan Digital Sky Survey.

SDSS-III is used to cover distant quasars at far reaches of the universe, the distribution of galaxies, the properties of stars in the Milky Way and also subjects such as dark matter and dark energy in the universe. Its instruments can make detailed measurements of 1000 galaxies at a time.

In 2012, BOSS had released their most accurate measurement yet of the distance scale of the universe during the era when dark energy activated.

Supernova Remnant at the Dragon's Head Nebula Captured

The European Southern Observatory using the FORS (FOcal Reducer and low dispersion Spectrograph) instrument captured a detailed image of NGC 2035 known as the Dragon's Head Nebula. The image shows filaments of gas and dust clouds that resulted from a supernova explosion.

A nebula is an interstellar cloud of dust, hydrogen, helium and other ionized gases.

The Dragon's Head Nebula is located in the Large Magellanic Cloud (LMC). The LMC is a galaxy 163,000 light years away and contains around 35 million stars. The LMC is smaller than the Milky Way galaxy at 14,000 light years wide compared to the Milky Way's width of 100,000 light years.

Extremely Rare Gravitational Lensed Dwarf Galaxy Imaged By Hubble Space Telescope

This picture from the NASA/ESA Hubble Space Telescope shows the most distant gravitational lens yet discovered. The glow at the centre of this picture is the central regions of a normal galaxy. By chance it is precisely aligned with a much more remote, young star-forming galaxy. The light from the more distant object is bent around the nearer object by its strong graviational pull to form a ring of multiple images. The chance of finding such an exactl alignment is very small, suggesting that there may be more star-forming galaxies in the early Universe than expected.
Credit: NASA/ESA/A. van der Wel

The Hubble Space Telescope as part of the CANDELS and COSMOS survey has captured an extremely rare and very distant dwarf galaxy that is gravitationally lensed. The dwarf galaxy is a record 9.4 billion light years away. It is a young starburst galaxy that forms a perfect Einstein ring, indicating a gravitational lens with very precise alignment of the lens and the background light source.

When two objects (the light source and a lensing mass) is observed, the light from the source is bent and deflected by the gravity of the lensing mass. It allows scientists to measure the mass of the lensing mass as well as the surrounding dark matter (which does not interact with light and only can be detected by gravitational effects).

Similar to looking at an object through a wine glass, the light is bent and forms a circle which is called an Einstein ring. The lens also magnifies the background light source, acting as a "natural telescope" that allows astronomers a more detailed look at distant galaxies than is normally possible.

In the captured image, the formation of the lens is extremely rare as the alignment has a one millimeter separation at a distance of 20 kilometers - a near perfect alignment.

Observation From Hubble CANDELS Survey Helps Visualize Galaxies 11 BIllion Years Ago

Galaxies are classified through a system devised by Edwin Hubble known as the Hubble Sequence. With the help of Hubble Space Telescope (named after the astronomer himself) and the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), data helped visualize the Hubble Sequence 11 billion years ago. Previous data has shown the Hubble Sequence of the Universe 8 billion years back.

The size, shape, form and even color of galaxies before are different from how it looks like today (see images at end of article). The physical formation has changed and are still changing and developing. Using two cameras aboard the Hubble Space Telescope, the Wide Field Camera 3 (WFC3) and the Advanced Camera for Surveys (ACS), CANDELS is set to explore the evolution of galaxies in the Universe and collect data that can give a glimpse of the Universe 1 billion years before the Big Bang.

Previous data were limited to the visible light spectrum which shows only the redshifted ultraviolet emission of the galaxies, which highlights star formation. By looking into the infrared spectrum of light (invisible to the human eye), the astronomers could observe how these distant galaxies appear in their visible rest frame (which is now redshifted), making it easier to compare to nearby galaxies.

Hubble Cosmos Survey Solves Mystery Behind Quenched Galaxy Growth

Image shows 20 galaxies that are no logner forming stars. Called Quenched galaxies, these have been imaged by the Hubble Cosmos Survey and can be identified by the crosshair at the center of each image.
Credit: NASA, ESA, M. Carollo (ETH Zurich)

Astronomers have recently discovered why quenched galaxies seem to be growing despite the fact that it doesn't produce stars anymore.

The previous theory for the supposed growth of quenched galaxies was that these small galaxies have merged with other smaller galaxies. By using the Hubble COSMOS observations, astronomers have found that larger galaxies switch off (stop forming new stars) at later times which gives the impression that previous quenched galaxies have grown over a duration of time.

Gas Outflow From Sculptor Galaxy (NGC 253) Hints At Scarcity Of High Mass Galaxies

This comparison picture of the nearby bright spiral galaxy NGC 253, also known as the Sculptor Galaxy, shows the infrared view from ESO’s VISTA Telescope (left) and a detailed new view of the cool gas outflows at millimetre wavelengths from ALMA (right).
Credit:ESO/ALMA (ESO/NAOJ/NRAO)/J. Emerson/VISTA

The Atacama Large Millimeter/submillimeter Array (ALMA) have observed massive molecular gas outflows ejected by the Sculptor Galaxy (NGC 253). This may explain how starburst galaxies behave and why there is a scarcity of very massive galaxies in the Universe.

Starburst galaxies are galaxies that have a very high rate of star formation compared to regular galaxies. They produce stars so fast that their available gas content is depleted in a shorter time span. Starburst galaxies like the Sculptor Galaxy are defined by the rate at which they convert gas into stars, the available quantity of gas available, and the timescale on which SFR (star formation rate) will consume the available gas with the age or rotation period of the galaxy.

With the available data supplied by ALMA, scientist can study and explain why there are so few massive galaxies around. And if the ejected gas theory holds true for most of these galaxies, they also want to find out what ultimately happens to to these gas outflows.

Black Hole Outflow From Galaxy NGC 3783 Surprises Observers

The VLTI (Very Large Telescope Interferometer) of the European Southern Observatory has observed that dust around a black hole at the NGC 3783 galaxy forms a cool wind that streams out from the black hole. This observation have surprised scientists since dust surrounding black holes have been observed to reach 700 to 1000 degrees Celsius.

The dust can be found at the torus of the black hole. The torus, which resembles a three dimensional donut (as seen on the image on the left), surrounds the black hole and is believed to be the source of high energy objects called active galactic nuclei (AGN). The supermassive black hole pulls in material from the surrounding region but it seems that the resulting radiation and energy that this produces also blows it away.

The hotter dust was mapped using the AMBER VLTI instrument at near-infrared wavelengths and the newer observations reported here used the MIDI instrument at wavelengths between 8 and 13 microns in the mid-infrared.

Black holes are regions in space where gravity is so strong that even light cannot escape its pull. Black holes are formed from stars that have exploded into a supernova and collapses into itself.

Black holes vary in size with some being 20 times more massive that the sun. Supermassive Black holes can reach a mass more than a million times than that of the Sun. Each galaxy has a supermassive black hole in its center.

The VLTI used to observe the black hole is made up of a combination of four VLT Unit Telescopes and four moveable 1.8-metre VLT Auxiliary Telescopes. It combines the light from several of these telescopes to form one observation through a process called interferometry. This process does not actually produce images but the generated measurements can be used to increase the level of detail of resulting observations.