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.

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.

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.

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.

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.

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.

VLT Survey Telescope Captures Messier 8 Lagoon Nebula in Rich Detail

The European Southern Observatory used its VLT Survey Telescope at Paranal Observatory in Chile to capture the image of the Lagoon Nebula in rich detail.

This is part of the The VST/OmegaCam Photometric Hα Survey (VPHAS+) which is one of three imaging surveys that use visible light with the VST. These are complemented by six infrared surveys with the VISTA survey telescope. There are also two other surveys that have distinct objectives; The Gaia-ESO Survey and the Public ESO Spectroscopic Survey of Transient Objects (PESSTO). The Gaia-ESO Survey uses the VLT to map the properties of more than 100 000 stars in the Milky Way. PESSTO is studying transient objects such as supernovas with the New Technology Telescope at La Silla.

These surveys are used to find out more about the Universe such as the nature of dark energy, quasars, structures of galaxies and studying other objects in detail.

Data from all of these surveys are now publicly available and accessible through the ESO Science Archive Facility (see related links below).

The Lagoon Nebula is an interstellar cloud of dust, hydrogen, helium and other ionized gases. Nebulas are regions where stars are formed. The materials needed to form stars such as hydrogen and other gases are abundant in a nebula. Stars are formed when dust and gas start to clump together and gain mass. As the mass gets more dense and generates heat, thermonuclear fusion starts and a star starts to form.

Unique Pairing of Star Forming Regions in Large Magellanic Cloud Imaged

By attaching the FOcal Reducer and low dispersion Spectrograph (FORS2) instrument to the ESO's Very Large Telescope, scientists were able to capture a sharp image of NGC 2020 and NGC 2014 side by side. NGC 2020 is the blue cloud in the image while the red colored cloud is NGC 2014.

The two star forming regions contain gas and dust that is essential to forming stars. NGC 2014 is surrounded by hydrogen gas which when exposed to radiation from hot young stars, ionizes the gas and produces a red glow. The bluish color of NGC 2020 is caused also by radiation from hot stars but instead of ionizing hydrogen, NGC 2020 is using oxygen which produces a blue glow.

The Large Magellanic Cloud is an irregular shaped galaxy containing around 35 million stars. It is believed to be a spiral shaped galaxy once but has become misshapen because of the gravitational pull of the Milky Way galaxy. The LMC is 163,000 light years away and is around 14,000 light years wide. By comparison, the Milky Way Galaxy is around 100,000 light years wide.

The distance between the Large Magellanic Cloud and the Milky Way Galaxy was accurately measured using light pulses from a binary star system within the LMC.

Lightest Exoplanet, HD95086b, Discovered by VLT 300 Light Years Away

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The Very Large Telescope (VLT) of the ESO has directly imaged an exoplanet that is about four to five times the mass of Jupiter. This makes this planet, the lightest exoplanet imaged.

The planet, known as HD95086 b, orbits a young star that is a bit more massive than the sun known as HD 95086. It's orbit is around two times the distance that Neptune orbits the sun and this star system is around 300 light years from the Earth.

HD95086 b is the first exoplanet in nine years that was directly imaged. Only around 12 exoplanets have been directly observed so far. Most other exoplanets were spotted by observing the dips of brightness produced when planets crossed in front of the stars it has been orbiting (transit method). Others have been discovered by studying the wobbling of a star caused by the gravitational pull of the orbiting planet known as the radial-velocity method.

There are over 3000 discovered exoplanets, 779 of these have been identified. The remaining 2300+ are being observed by the Kepler space telescope for confirmation.

Glowing Green Cell-Like Object - Nebula IC 1295 Imaged in Space

Nebula IC 1295 is a glowing green nebula that resembles a cellular microorganism. The ESO's Very Large Telescope captured the most detailed image of the planetary nebula every taken.

Nebulae or Nebulas are interstellar clouds of dust and gasses. These regions in space are where stars are formed. The clouds of gas and dust in a nebula clump together and over millions of years form a star. Even planets and other interstellar objects are also formed in nebulae.

These are four general types of nebulas; Diffuse Nebula, Planetary Nebula, Protoplanetary Nebula and a Supernova Remnant. Nebula IC 1295 is a planetary nebula. Planetary nebulas are formed when ionized gas is ejected from stars. The ejected gas then expands into a glowing shell which forms the planetary nebula.

Planet Forming In Gas Cloud Near Star HD 100546 Discovered

The European Southern Observatory's VLT (Very Large Telescope) has discovered what is likely a forming planet within a thick disc of gas and dust.

This is the first time such a discovery has been made. Up until now, scientists have not directly observed or have discovered a planet that is in the process of forming. This discovery, when confirmed, may greatly advance planet formation theories and test current theories against the observation.

In 1995, a planet orbiting a sun-like star outside of the Solar System was discovered. Soon after, several hundred exoplanets and planetary systems outside of the Solar System has been found. Currently, there are only theories on how planets are formed based on observation of the Solar System and the planets within (which are all estimated to be more than 4 billion years old).

Compared to the Earth, the protoplanet (forming planet) has an orbit 70 times further from its star than the Earth does from the Sun. The distance of the orbit does not fit with current planet formation theories. It may be that the planet formed within the inner orbital regions and drifted outwards. Although there is still a slim possibility that the planet formed in its current position.

Cosmic Rays Confirmed To Originate From Supernovas In Two Separate Announcements

When stars explode, the supernovas send off shock waves, which accelerate protons to cosmic-ray energies through a process known as Fermi acceleration. In this mechanism, named for Enrico Fermi who first hypothesized it, the protons gain energy from collisions with turbulent magnetic fields on either side of a shock wave. Though many details of Fermi acceleration remain unknown, new results from the Fermi Gamma-ray Space Telescope provide overwhelming evidence that the mechanism is indeed responsible for producing many of the galaxy's cosmic ray protons.
Credit: Greg Stewart, SLAC National Accelerator Laboratory

In two separate announcements (and two separate studies), the European Southern Observatory and the Kavli Institute for Particle Astrophysics and Cosmology at the Department of Energy's (DOE) SLAC National Accelerator Laboratory confirmed that cosmic rays come from exploding stars or supernovas.

Cosmic rays are high energy particles from space. These particles travel at close to the speed of light and originate from outside the Solar System. They have very high energy that they can penetrate the Earth's atmosphere and even through solid rock at the surface. Prior to the announcement, its origin and how it was formed has been a mystery.

The ESO together with the Max Planck Institute for Astronomy in Heidelberg Germany, used the VIMOS Equipment on the Very Large Telescope (VLT) to study SN 1006, a supernova first observed in the year 1006, to gather data and base their discovery of the cosmic ray mystery. Their study, An Integral View of Fast Shocks around Supernova 1006, is appearing in the 14 February 2013 issue of the journal Science.

The Kavli Institute, NASA, and Stanford University used the Large Area Telescope (LAT), which sits onboard the Fermi Gamma-ray Space Telescope to base their findings. They used the telescope to study two supernova remnants, IC 433 and W44. Both are located within the Milky Way with IC 443 5,000 light years away from Earth in the constellation Gemini, and W44 is located about 10,000 light years away, in the constellation of Aquila. Their study, Detection of the Characteristic Pion-Decay Signature in Supernova Remnants, will be appearing in the February 15 2013 issue of the journal Science.

New Space Instrument, K-band Multi-Object Spectrograph (KMOS), Can Observe 24 Objects In Space At The Same Time

A new space instrument was attached to the ESO's Very Large Telescope. The K-band Multi-Object Spectrograph (KMOS) has 24 robot arms that can study and observe 24 objects such as galaxies all at the same time.

Space telescopes and instruments study and gather data about the Universe by observing the light emitted by these objects. Stars can be seen by the naked eye because of the light they emit.

But as farther the objects are, the light from these objects move from visible light to the infra-red spectrum which is not visible to the eye. This is called the redshift.

To explain redshift, it is best to compare it to hearing a police or ambulance siren. As the siren gets closer, the pitch gets higher, as the siren passes and moves away, the pitch goes lower. This is known as the Doppler effect.

This Doppler effect works the same way with light waves, as the object is far away, the wavelength of light gets lower and moves toward the red side of the spectrum. Because of the expansion of the Universe, stars and galaxies are moving farther from each other which explains the redshift.

Largest Area Image of Carina Nebula Captured By VLT and OmegaCAM

One of the largest nebula in outer space, the Carina Nebula, has been imaged by the VLT in very fine detail with the help of its new camera, the OmegaCAM.

A nebula is a cloud of gas and dust in interstellar space. Most nebula are formed when surrounding dust and gas collapse into each other due to its weight and gravity. As these gas and dust collapse into each other, new stars are formed.

Other nebulae are formed when a star reaches the end of its life and explodes into a supernova. Ionized gas and matter are ejected by the supernova as it explodes and a neutron star usually is formed in the middle of this type of nebula.

Nebulae glow in different colors depending on the type of gas surrounding them. Hydrogen gas, for example, emits a reddish glow while ionized oxygen has a greenish glow. The Carina Nebula glows red as imaged by the VLT.

Nebulae are bright and emit a glow because of the ionization of the surrounding gas by ultraviolet radiation. Ultraviolet light is invisible to the naked eye but this type of energy ionizes the surrounding gas which makes it light up. This is similar to the process of a fluorescent light tube.

Rare Galaxy Class Identified - Green Bean Galaxy J2240

The Very Large Telescope of the ESO has detected and imaged a new class of galaxy that is glowing green. The green glow is not just limited to the core but is emitted throughout the whole of the galaxy. The identified galaxy, J2240, is classified as a Green Bean Galaxy.

Most galaxies has a giant black hole in the center. As the black hole sucks the surrounding matter in, radiation and energy is given off which makes the area glow. The Milky Way is believed to host a supermassive black hole in its core but the surrounding dust and gas may be blocking the light for Earth instruments to detect.

There are also a class of galaxies called Green Pea galaxies. They are characterized as very small luminous galaxies and has no relation to the newly classified Green Bean galaxies except for their size.

Green Bean Galaxies are entire galaxies that glow under the intense radiation from the region around its core where the central black hole lies.

Planet Floating Freely Through Space Without An Orbit Discovered

The Very Large Telescope (VLT) of the European Southern Observatory (ESO) and the Canada-France-Hawaii Telescope have discovered a planet that is freely wandering through space. It has no orbit nor a star attached to it. This planet free-floating planet is labeled CFBDSIR2149 and also referred to as CFBDSIR J214947.2-040308.9.

Free-floating planets are objects in space that are not paired up or connected to a star. They roam the universe without a predetermined orbit since there is no star to supply the gravity to put them in their place.

Binary Stars Discovered Orbiting Center Of Fleming 1 Nebula By ESO's Very Large Telescope (VLT)

The European Southern Observatory's Very Large Telescope (VLT) disovered a pair of stars orbiting each other at the center of the planetary nebula, Fleming 1. This discovery may explain the pattern Fleming 1 forms from its ejected gas.

ESO News: Two Contests To Commemorate 50th Anniversary of ESO - Choose What The VLT Observes Or Visit The VLT

ESO builds and operates some of the most advanced telescopes on Earth including the Very Large Telescope (VLT) at the Paranal Observatory. These huge machines have made many fascinating discoveries about the Universe. Now, for the first time in its history, you can decide what to observe with the VLT, or even win an amazing trip to Chile’s breathtaking Atacama Desert to help make the observations yourself.

The first of our two anniversary competitions is called Choose What the VLT Observes.

Usually, astronomers have to prepare a detailed plan long in advance, describing why they want to use the VLT, and only a small fraction of them are given the chance. But for you, it’s going to be rather easier.

ESO has already pre-selected some interesting celestial objects that are visible in the sky on the 50th anniversary of ESO — 5 October 2012 — and fit in VLT’s field of view [1]. All you need to do is cast your vote for the object you like most. The one that gets the most votes will be observed using the VLT on the 50th anniversary day.

We will draw a winner and ten runners up from among those who voted (you do not have to have voted for the winning object). The winner will receive one of the latest iPads and the runners up will receive ESO products including books, DVDs and other goodies.

Next, what about visiting the VLT to help make the observations of the winning object yourself?

VLT Detailed Image of Spiral Galaxy NGC 1187 That Has Hosted Two Supernova Explosions

A new image taken with ESO’s Very Large Telescope shows the galaxy NGC 1187. This impressive spiral lies about 60 million light-years away in the constellation of Eridanus (The River). NGC 1187 has hosted two supernova explosions during the last thirty years, the latest one in 2007. This picture of the galaxy is the most detailed ever taken.

A supernova is an exploding star that expends more energy than it normally would. Supernovae or supernovas are extremely luminous and emit a powerful burst of radiation that often briefly outshines an entire galaxy. During this period a supernova can radiate as much energy as the Sun is expected to emit over its entire life span. The explosion expels much or all of a star's material at a velocity of up to 30,000 km/s (10% of the speed of light), driving a shock wave into the surrounding interstellar medium. This shock wave sweeps up an expanding shell of gas and dust called a supernova remnant.

It is estimated that one to two supernovae explode in the Milky Way each century. The spiral galaxy NGC 1187 has had two supernova explosions detected, 25 years apart. The first was in 1982, and the second in 2007.

A Blue Whirlpool in The River

The galaxy NGC 1187 ^[1] is seen almost face-on, which gives us a good view of its spiral structure. About half a dozen prominent spiral arms can be seen, each containing large amounts of gas and dust. The bluish features in the spiral arms indicate the presence of young stars born out of clouds of interstellar gas.

Looking towards the central regions, we see the bulge of the galaxy glowing yellow. This part of the galaxy is mostly made up of old stars, gas and dust. In the case of NGC 1187, rather than a round bulge, there is a subtle central bar structure. Such bar features are thought to act as mechanisms that channel gas from the spiral arms to the centre, enhancing star formation there.

Around the outside of the galaxy many much fainter and more distant galaxies can also be seen. Some even shine right through the disc of NGC 1187 itself. Their mostly reddish hues contrast with the pale blue star clusters of the much closer object.

Possible Visual Evidence of a Dark Galaxy Spotted By VLT

A dark galaxy is believed to be an invisible galaxy composed of dark matter. The existence of a dark galaxy is still a hypothesis.

The theory of the existence of a dark galaxy came up upon observing galaxy NGC 4254. It was observed that this galaxy collided with another galaxy because of the presence of gas being siphoned away into a tenuous stream, and one of its spiral arms is being stretched out. There is no evidence of another galaxy involved in the collision which brought up the theory of dark galaxies.

Dark galaxies have no detectable stars and are believed to be invisible to the known visual spectrums. There is experimental evidence to support the existence of dark galaxies, although scientists have no conclusive evidence and continue their research. Scientists have proposed a means to track down the dark dwarf galaxies that should be orbiting the Milky Way, saying they have now found evidence of one.

For the first time, dark galaxies — an early phase of galaxy formation, predicted by theory but unobserved until now — may have been spotted. These objects are essentially gas-rich galaxies without stars. Using ESO’s Very Large Telescope, an international team thinks they have detected these elusive objects by observing them glowing as they are illuminated by a quasar.

Dark Galaxies of the Early Universe Spotted for the First Time

Dark galaxies are small, gas-rich galaxies in the early Universe that are very inefficient at forming stars. They are predicted by theories of galaxy formation and are thought to be the building blocks of today’s bright, star-filled galaxies. Astronomers think that they may have fed large galaxies with much of the gas that later formed into the stars that exist today.

Because they are essentially devoid of stars, these dark galaxies don’t emit much light, making them very hard to detect. For years astronomers have been trying to develop new techniques that could confirm the existence of these galaxies. Small absorption dips in the spectra of background sources of light have hinted at their existence. However, this new study marks the first time that such objects have been seen directly.

“Our approach to the problem of detecting a dark galaxy was simply to shine a bright light on it.” explains Simon Lilly (ETH Zurich, Switzerland), co-author of the paper. “We searched for the fluorescent glow of the gas in dark galaxies when they are illuminated by the ultraviolet light from a nearby and very bright quasar. The light from the quasar makes the dark galaxies light up in a process similar to how white clothes are illuminated by ultraviolet lamps in a night club.”^[1]