Showing posts with label eso. Show all posts
Showing posts with label eso. Show all posts

09 December 2015

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.

16 September 2015

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.

10 July 2015

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.

09 July 2015

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.

17 April 2015

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.

15 April 2015

Dark Matter Interactions Observed in Galaxy Collision at Abell 3827



While studying the simultaneous collision of four galaxies in the galaxy cluster Abell 3827, the European Southern Observatory's VLT and NASA/ESA's Hubble Space Telescope may have, for the first time, observed dark matter interactions with other dark matter.

The nature of dark matter is still a mystery but it is believed that it comprises 85% of the Universe’s mass; the rest being "normal matter". Without dark matter, galaxies would not be able to hold itself together and would fling themselves apart while they rotate. Dark matter keeps these galaxies together due to the constraining effect of its' gravity.

Researches observed that during the collision, one clump of dark matter appeared to be lagging behind the galaxy it surrounds. The dark matter is currently 5000 light-years behind the galaxy.

Dark matter has always been observed interacting with gravity but the computer simulation of the four galaxy collision at Abell 3827 show that extra friction from the collision would slow down dark matter and that the nature of that interaction is not gravity and still is unknown. It is also uncertain how long it took for the collision to happen.The friction that slowed the dark matter could have been a very weak force acting over about a billion years, or a relatively stronger force acting for “only” 100 million years.

04 February 2015

Hidden Objects Along Center of Milky Way Detected Through Infrared



The VVV survey (VISTA Variables in the Via Lactea) of the VISTA telescope at ESO’s Paranal Observatory in Chile has allowed astronomers to see the central parts of the Milky Way as never before.

Using infrared light, the VVV imaged the Trifid Nebula and revealed that the gas cloud has been hiding two Cepheid variable stars directly behind it but at a far distance.

The pair of cepheid stars hidden by the Trifid Nebula is estimated to be around 37,000 light years away from Earth while the Trifid Nebula is at 5,200 light years away. Cepheid variables are unstable bright stars that brightens and fades over time, in this case, a period of 11 days.

These two stars are the only two known Cepheid variables that are close to the central plane of the Milky Way which is 27,000 light years away from Earth.

The Vista Variables in the Via Lactea is an astronomical survey to map the Milky Way, it's bulge and the disk area close to the center of the galaxy. The VVV survey previously assisted astronomers in constructing a three dimensional map of the Milky Way

28 January 2015

Cometary Globule CG4 (God's Hand) Imaged by VLT



The VLT Survey Telescope, the largest telescope designed to exclusively survey the skies in visible light, imaged cometary globule CG4 or God's Hand as it is also known.

Cometary globules are faint, dimly lit, and hard to detect gas clouds that resemble comets although they have no relation to them. Cometary globules are identified by their small size and are found to have isolated, relatively small clouds of neutral gas and dust surrounded by hot ionised material.

It is a mystery to astronomers as to how cometary globules are formed.

God's Hand is 1300 light years from Earth and can be found in the constellation Puppis (The Poop, or Stern). CG4 gas a diameter if 1.5 light years and its tail is 8 light years long. Compared to other celestial objects, the dimensions of CG4 are small.

This picture comes from the ESO Cosmic Gems programme, an outreach initiative to produce images of interesting, intriguing or visually attractive objects using ESO telescopes, for the purposes of education and public outreach. The programme makes use of telescope time that cannot be used for science observations. All data collected may also be suitable for scientific purposes, and are made available to astronomers through ESO’s science archive.

14 January 2015

Next-Generation Transit Survey (NGTS) To Hunt and Study Exoplanets


The Next-Generation Transit Survey (NGTS), a wide-field observing system by the European Southern Observatory (ESO) was launched and has achieved first light.

The Survey will focus on transiting exoplanets or planets that passes in front of their parent star. This movement by the exoplanets produces a slight dimming of the light emitted by the stars which can be detected by light sensitive instruments. The telescopes of NGTS will be focusing on discovering Neptune-sized and smaller planets, with diameters between two and eight times that of Earth.

The Next-Generation Transit Survey is located at the European Southern Observatory's Paranal Observatory in northern Chile. The site benefits from the superb observing conditions and its excellent support facilities.

The NGTS telescopes are made up of an array of 12 modified versions of small high-quality commercial telescopes made by Astro Systeme Austria (ASA). Each has an aperture of 20 centimeters. The NGTS cameras are modified ikon-L cameras by Andor Technology Ltd built around red-sensitive deep-depletion CCDs by e2v.

The NGTS was made possible by a consortium comprised of the UK, Switzerland, and Germany.

07 January 2015

Mysterious Void In Space In Latest MPG/ESO Telescope Image



In the newly released ESO image, the starfield seemed to be devoid of stars in a particular area.

The new image of the MPG/ESO 2.2 meter telescope shows an area of empty space amidst a field of stars. This "dark area" is not really empty space but a dark cloud called LDN 483 or Lynds Dark Nebula 483.

Nebulas or Nebulae are clouds of dust and gas in space where planets and stars are formed. Dark Nebulas are different in the sense that the cloud has enough material of dust inside of it that it completely blocks all the light emitted by the stars behind it. Compared to other types of nebulae, dark nebulae are believed to have the most conducive and fertile environment to create stars.

LDN 483 is around 700 light-years away in the constellation of Serpens (The Serpent).

15 October 2014

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.

23 July 2014

Star Cluster NGC 3293 Nestled Against Clouds of Gas and Dust in the Carina Constellation



ESO’s La Silla Observatory in Chile released a striking image of star cluster NGC 3293 with clouds of glowing red gas and streaks of dust in the background. NGC is composed of young stars are believed to be less than ten million years old and is about 8000 light-years from Earth in the constellation of Carina (The Keel).

Using the Wide Field Imager (WFI) installed on the MPG/ESO 2.2-meter telescope at the observatory, astronomers study young star clusters such as NGC 3293 to learn more about the evolution of stars.

Star cluster are groups of stars that are held together by their own gravitational fields. Open star clusters and globular are the two types of clusters. NGC 3293 is an open star cluster; loosely clustered groups of young stars. The gravitational attraction between the stars in an open star cluster may be weak or non existent.

Globular star clusters are made up of hundreds of thousands of very old stars that are gravitationally bound. These stars are attracted to each other and form a very tight sphere. The stars within a globular star cluster orbit a galactic core and the amount of stars within get denser going toward the center.

These open clusters each formed from a giant cloud of molecular gas and their stars are held together by their mutual gravitational attraction. But these forces are not enough to hold a cluster together against close encounters with other clusters and clouds of gas as the cluster’s own gas and dust dissipates. So, open clusters will only last a few hundred million years, unlike their big cousins, the globular clusters, which can survive for billions of years, and hold on to far more stars.

20 June 2014

European Extremely Large Telescope Groundbreaking in Cerro Armazones



The largest optical/infrared telescope in the world, the European Extremely Large Telescope (E-ELT), held its groundbreaking ceremony at the 3000 meter peak of Cerro Armazones in Chile.

The E-ELT is planned to start operations within the next decade; around 2024. Projects for the European Extremely Large Telescope include tracking down habitable Earth-like planets, finding out more about dark matter and dark energy, and measuring the properties of the first stars and galaxies.

Civil works in the the Cerro Armazones started in March 2014 and are expected to take 16 months. These include the laying and maintenance of a paved road, the construction of the summit platform and the construction of a service trench to the summit.

09 April 2014

Bubble Shaped Planetary Nebula Abell 33 In Hydra Constellation Imaged



A Nebula is an interstellar cloud made up of dist and gases. The word "nebula" is latin for cloud. These astronomical objects are regions where stars are made due to the materials present in the nebula which are needed to form a star.

Dust and ionized gasses such as hydrogen and helium start to amass together getting larger and larger until they become massive enough to form a star. Some of the materials present in the nebula can also form planets and other astronomical object.

Abell 33 found in the constellation Hydra, 2500 light-years from Earth, is a planetary nebula. This type of nebula does not form planets as the name implies. It was a misnomer that has been carried on when William Herschel incorrectly thought of that and coined the term. It has been called that every since.

Planetary nebulas are emission type nebulas that are formed when stars eject ionized gas in its later stages, this gas forms an expanding glowing shell. They are important in the evolution of stars since planetary nebulas contain heavy elements such as carbon, nitrogen, and oxygen.

02 April 2014

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.

05 March 2014

Multi Unit Spectroscopic Explorer Attached To VLT Depicts Galaxies and Objects in 3D



The European Southern Observatory's Very Large Telescope (VLT)has a new instrument installed today that will help in observing distant galaxies. The Multi Unit Spectroscopic Explorer will help astronomers view far away objects such as galaxies and determine its properties such as mass and chemical composition. It can also capture images of these objects in high resolution 3D.

MUSE is an instrument that measures properties of light such as wavelengths and intensities and combines it with high resolution imaging. By using a technique called integral field spectroscopy, MUSE can study the properties of different parts of an object, measure its mass, and observe its rotation at the same time. With the advanced technology of MUSE in terms of sensitivity, efficiency and resolution, resulting images and data are far ahead of previous spectroscopic imaging.

With MUSE, astronomers can can move through the data and study different views of an object at different wavelengths, just like tuning a television to different channels at different frequencies.

This image above is of the Orion Nebula as imaged by MUSE early this year.

19 February 2014

Star Cluster Messier 7 Shines Bright At The Tail End of The Scorpion



Star Cluster Messier 7 can be found shining brightly at the end of the tail end of the constellation Scorpius (The Scorpion). This group of stars is also known as Ptolemy's Cluster in honor of Claudius Ptolemy who discovered this star cluster around 130 AD. As the name implies, it is the 7th entry of Charles Messier's Catalog of Nebulae and Star Clusters done in 1764.

Messier 7 is about 800 light years from the Earth and is comprised of about 100 stars. It is a bright patch of stars that is visible to the naked eye found near the tail of the Scorpius constellation.

The latest images from the European Southern Observatory's Wide Field Imager on the MPG/ESO 2.2-metre telescope shows Messier 7 shining like diamonds against the backdrop of a multitude of stars.

These bright stars are believed to be close to exploding into a supernova as it is over 200 million years old.

Messier 7 is an open star cluster. Open star clusters are loose clustered groups of stars that are held together by a very weak gravitational attraction to each other.

05 February 2014

Probing the Secrets of Asteroid Itokawa


Schematic of Asteroid Itokawa

Using the New Technology Telescope (NTT) by the European Southern Observatory, scientists have, for the first time, studied the internal structure of an asteroid.

The NTT studied the peanut shaped asteroid Itokawa. It helped scientists measure the asteroid's brightness variation as it rotates. Knowing the irregular peanut shape of Itokawa, the data gathered allowed them to accurately calculate its spin period. This also gave the scientists an insight to find out what the asteroid is like below the surface and also at its core.

This discovery, already a big step in understanding asteroids, will also help understand how planets are formed and what happens during outer space collisions.

30 January 2014

VLT Successfully Maps Surface Features Of Brown Dwarf Luhman 16B



The European Southern Observatory for the first time has mapped the surface of a brown dwarf. ESO's Very Large Telescope charted the dark and light surface of Luhman 16B, an astronomical object known as a brown dwarf.

Brown Dwarfs are also known as a substar since these objects are too large to be planets but are not massive enough to be called stars. These objects are believed to be formed the way stars are formed but did not have enough density at the core to start a nuclear fusion.

The surface map of Luhman 16B is the first charting of the brown star which included the light and dark features of the surface. It is also the first mapping of the weather on the surface of Luhman 16B.

The brown dwarf, discovered in 2013, is only six light years from Earth and can be found in the southern constellation of Vela (The Sail). Luhman 16B forms a pair with Luhman 16A which is the brighter of the two components. The pair is collectively referred to as Luhman 16AB.

The imaging was made possible with the CRyogenic high-resolution InfraRed Echelle Spectrograph (CRIRES) attached to the VLT.