Pesona Cantik Galaksi di alam semsesta

Messier 78 (a reflection nebula in Orion)

This new image of the reflection nebula Messier 78 was captured using the Wide Field Imager camera on the MPG/ESO 2.2-metre telescope at the La Silla Observatory, Chile. This colour picture was created from many monochrome exposures taken through blue, yellow/green and red filters, supplemented by exposures through a filter that isolates light from glowing hydrogen gas. The total exposure times were 9, 9, 17.5 and 15.5 minutes per filter, respectively.

ESO’s VLT reveals the Carina Nebula's hidden secrets

This broad image of the Carina Nebula, a region of massive star formation in the southern skies, was taken in infrared light using the HAWK-I camera on ESO’s Very Large Telescope. Many previously hidden features, scattered across a spectacular celestial landscape of gas, dust and young stars, have emerged.

The Eagle Nebula

Three-colour composite mosaic image of the Eagle Nebula (Messier 16, or NGC 6611), based on images obtained with the Wide-Field Imager camera on the MPG/ESO 2.2-metre telescope at the La Silla Observatory. At the centre, the so-called “Pillars of Creation” can be seen. This wide-field image shows not only the central pillars, but also several others in the same star-forming region, as well as a huge number of stars in front of, in, or behind the Eagle Nebula. The cluster of bright stars to the upper right is NGC 6611, home to the massive and hot stars that illuminate the pillars. The “Spire” — another large pillar — is in the middle left of the image.

This image is a composite of 3 filters in the visible range: B (blue), V (green) and R (red).

The Eagle's EGGs

Messier 16 (M16), also known as the Eagle Nebula, is located in the southern constellation of Serpens (the Snake).

Using the infrared multi-mode ISAAC instrument on the 8.2-m VLT ANTU telescope, European astronomers were able to image the Eagle Nebula at near-infrared wavelength. The ISAAC near-infrared images cover a 9 x 9 arcminutes region, in three broad-band colours and with sufficient sensitivity to detect young stars of all masses and — most importantly — with an image sharpness as good as 0.35 arcseconds.

The wide-field view of M16 shows that there is much happening in the region. The first impression one gets is of an enormous number of stars. Those which are blue in the infrared image are either members of the young NGC 6611 cluster — whose massive stars are concentrated in the upper right (north west) part of the field — or foreground stars which happen to lie along the line of sight towards M16.

Most of the stars are fainter and more yellow. They are ordinary stars behind M16, along the line of sight through the galactic bulge, and are seen through the molecular clouds out of which NGC 6611 formed. Some very red stars are also seen: these are either very young and embedded in gas and dust clouds, or just brighter stars in the background shining through them.

This photo is the result of a three-colour composite mosaic image of the Eagle Nebula (Messier 16), based on 144 individual images obtained with the infrared multi-mode instrument ISAAC on the ESO Very Large Telescope (VLT) at the Paranal Observatory. At the centre, the so-called "Pillars of Creation" can be seen. This wide-field infrared image shows not only the central three pillars but also several others in the same star-forming region, as well as a huge number of stars in front of, in, or behind the Eagle Nebula. The cluster of bright blue stars to the upper right is NGC 6611, home to the massive and hot stars that illuminate the pillars.

Technical information: This image was made using the near-infrared camera ISAAC on the ESO 8.2-m VLT ANTU telescope on April 8 and May 8 - 10, 2001. The full field measures approximately 9.1 x 9.1 arcmin, covering roughly 17 x 17 light-years (5.3 x 5.3 pc) at the distance to the region (about 6,500 light-years or 2 kpc). This required a 16-position mosaic (4 x 4 grid) of ISAAC pointings : at each pointing, a series of images were taken in each of the near-infrared J s - (centred at 1.24 µm wavelength), H- (1.65µm), and K s - (2.16 µm) bands. North is up and East left.
The total integration time for each pixel in the mosaic was 1200, 300, and 300 seconds in the central 4.5 x 4.5 arcmin region, and 200, 50, and 50 seconds in the outer part, in J s -, H-, and K s - bands, respectively. The seeing FWHM (full width at half maximum) was excellent, at 0.38, 0.36, and 0.33 arcsec in J s, H, and K s, respectively. Point sources are detected in the central region at the 3-sigma level (brightest pixel above background noise) at 22.6, 21.3, and 20.4 magnitudes in J s, H, and K s, respectively. These limits imply that a 1 million year old, 0.075 solar-mass object on the star/brown dwarf boundary could be detected in M16 through roughly 15, 20, and 30 magnitudes of visual extinction at J s, H, and K s, respectively.
After removal of instrumental signatures and the bright infrared sky background, all frames in a given band were carefully aligned and adjusted to form a seamless mosaic. The three monochromatic mosaics were then scaled to the cube root of their intensities to reduce the enormous dynamic range and enhance faint nebular features. The mosaics were then combined to create the colour-coded image, with the J s -band being rendered as blue, the H-band as green, and the K s -band as red. A total of 144 individual 1024 x 1024 pixel ISAAC images were merged to form this mosaic.

The Crab Nebula in Taurus

This photo shows a three colour composite of the well-known Crab Nebula (also known as Messier 1), as observed with the FORS2 instrument in imaging mode in the morning of November 10, 1999. It is the remnant of a supernova explosion at a distance of about 6,000 light-years, observed almost 1,000 years ago, in the year 1054. It contains a neutron star near its center that spins 30 times per second around its axis (see below).

In this picture, the green light is predominantly produced by hydrogen emission from material ejected by the star that exploded. The blue light is predominantly emitted by very high-energy ("relativistic") electrons that spiral in a large-scale magnetic field (so-called synchrotron emission). It is believed that these electrons are continuously accelerated and ejected by the rapidly spinning neutron star at the centre of the nebula and which is the remnant core of the exploded star. This pulsar has been identified with the lower/right of the two close stars near the geometric center of the nebula, immediately left of the small arc-like feature, best seen in ESO Press Photo eso9948. Technical information: ESO Press Photo eso9948 is based on a composite of three images taken through three different optical filters: B (429 nm; FWHM 88 nm; 5 min; here rendered as blue), R (657 nm; FWHM 150 nm; 1 min; green) and S II (673 nm; FWHM 6 nm; 5 min; red) during periods of 0.65 arcsec (R, S II) and 0.80 (B) seeing, respectively. The field shown measures 6.8 x 6.8 arcminutes and the images were recorded in frames of 2048 x 2048 pixels, each measuring 0.2 arcseconds. North is up; East is left.

Sumber : ESO

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Bintang dan Bintang

the young star V883 Orionis

The brilliant star VFTS 682 in the Large Magellanic Cloud

This view shows part of the very active star-forming region around the Tarantula Nebula in the Large Magellanic Cloud, a small neighbour of the Milky Way. At the exact centre lies the brilliant but isolated star VFTS 682 and to its lower right the very rich star cluster R 136. The origins of VFTS 682 are unclear — was it ejected from R 136 or did it form on its own? The star appears yellow-red in this view, which includes both visible-light and infrared images from the Wide Field Imager at the 2.2-metre MPG/ESO telescope at La Silla and the 4.1-metre infrared VISTA telescope at Paranal, because of the effects of dust.

Artist’s impression of dust formation around a supernova explosion

This artist’s impression shows dust forming in the environment around a supernova explosion. VLT observations have shown that these cosmic dust factories make their grains in a two-stage process, starting soon after the explosion, but continuing long afterwards.

Outbursts from a newborn star

A pair of jets protrude outwards in near-perfect symmetry in this image of Herbig-Haro object (HH) 212, taken by ESO’s already decommissioned Infrared Spectrometer And Array Camera (ISAAC).

The object lies in the constellation of Orion (The Hunter) in a dense molecular star-forming region, not far from the famous Horsehead Nebula. In regions like this, clouds of dust and gas collapse under the force of gravity, spinning faster and faster and becoming hotter and hotter until a young star ignites at the cloud’s centre. Any leftover material swirling around the newborn protostar comes together to form an accretion disc that will, under the right circumstances, eventually evolve to form the base material for the creation of planets, asteroids and comets.

Although this process is still not fully understood, it is common that a protostar and its accretion disc, as seen here edge-on, are the cause of the jets in this image. The star at the centre of HH 212 is indeed a very young star, at only a few thousand years old. Its jets are remarkably symmetric, with several knots appearing at relatively stable intervals. This stability suggests that the jet pulses vary quite regularly, and over a short timescale — maybe even as short as 30 years! Further out from the centre, large bow shocks spread out into interstellar space, caused by ejected gas colliding with dust and gas at speeds of several hundred kilometres per second.

A cosmic flame

Sparkling at the edge of a giant cloud of gas and dust, the Flame Nebula, also referred to as NGC 2024, is in fact the hideout of a cluster of young, blue, massive stars, whose light sets the gas ablaze. Located 1,300 light-years away towards the constellation of Orion, the nebula owes its typical colour to the glow of hydrogen atoms, heated by the stars. The latter are obscured by a dark, forked dusty structure in the centre of the image and are only revealed by infrared observations.

This image is based on data acquired with the 1.5-metre Danish telescope at ESO’s La Silla Observatory in Chile, combining three exposures in the filters B (40 seconds), V (80 seconds) and R (40 seconds).

Infrared view of the Rho Ophiuchi star-forming region

This image shows the Rho Ophiuchi star-forming region in infrared light, as seen by NASA’s Wide-field Infrared Explorer (WISE). Blue and cyan represent light emitted at wavelengths of 3.4 and 4.6 micrometres, which is predominantly from stars. Green and red represent light from 12 and 22 micrometres, respectively, which is mostly emitted by dust.

Sumber : ESO

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Nabulae

The Horsehead Nebula

A reproduction of a composite colour image of the Horsehead Nebula and its immediate surroundings. It is based on three exposures in the visual part of the spectrum with the FORS2 multi-mode instrument at the 8.2-m KUEYEN telescope at Paranal. It was produced from three images, obtained on February 1, 2000, with the FORS2 multi-mode instrument at the 8.2-m KUEYEN Unit Telescope and extracted from the VLT Science Archive Facility . The frames were obtained in the B-band (600 sec exposure; wavelength 429 nm; FWHM 88 nm; here rendered as blue), V-band (300 sec; 554 nm; 112 nm; green) and R-band (120 sec; 655 nm; 165 nm; red). The original pixel size is 0.2 arcsec. The photo shows the full field recorded in all three colours, approximately 6.5 x 6.7 arcmin 2 . The seeing was about 0.75 arcsec.

This image is available as a mounted image in the ESOshop.

The Helix Nebula

This colour-composite image of the Helix Nebula (NGC 7293) was created from images obtained using the Wide Field Imager (WFI), an astronomical camera attached to the 2.2-metre Max-Planck Society/ESO telescope at the La Silla observatory in Chile. The blue-green glow in the centre of the Helix comes from oxygen atoms shining under effects of the intense ultraviolet radiation of the 120 000 degree Celsius central star and the hot gas. Further out from the star and beyond the ring of knots, the red colour from hydrogen and nitrogen is more prominent. A careful look at the central part of this object reveals not only the knots, but also many remote galaxies seen right through the thinly spread glowing gas.

This image was created from images through blue, green and red filters and the total exposure times were 12 minutes, 9 minutes and 7 minutes respectively.

This image is available as a mounted image in the ESOshop.

The Orion Nebula

This spectacular image of the Orion Nebula star-formation region was obtained from multiple exposures using the HAWK-I infrared camera on ESO’s Very Large Telescope in Chile. This is the deepest view ever of this region and reveals more very faint planetary-mass objects than expected.

The Carina Nebula

This broad image of the Carina Nebula, a region of massive star formation in the southern skies, was taken in infrared light using the HAWK-I camera on ESO’s Very Large Telescope. Many previously hidden features, scattered across a spectacular celestial landscape of gas, dust and young stars, have emerged.

The star-forming region Messier 17

The first released VST image shows the spectacular star-forming region Messier 17, also known as the Omega Nebula or the Swan Nebula, as it has never been seen before. This vast region of gas, dust and hot young stars lies in the heart of the Milky Way in the constellation of Sagittarius (The Archer). The VST field of view is so large that the entire nebula, including its fainter outer parts, is captured — and retains its superb sharpness across the entire image. The data were processed using the Astro-WISE software system developed by E.A. Valentijn and collaborators at Groningen and elsewhere.

Stellar nursery NGC 3603

NGC 3603 is a starburst region : a cosmic factory where stars form frantically from the nebula’s extended clouds of gas and dust. Located 22,000 light-years away from the Sun, it is the closest region of this kind known in our galaxy, providing astronomers with a local test bed for studying the intense star formation processes, very common in other galaxies, but hard to observe in detail because of their large distance.

The newly released image, obtained with the FORS instrument attached to one of the four 8.2-metre VLT Unit Telescopes at Cerro Paranal, Chile, is a three-colour combination of exposures acquired through visible and near-infrared (V, R, I) filters. This image portrays a wider field around the stellar cluster and reveals the rich texture of the surrounding clouds of gas and dust. The field of view is 7 arcminutes wide.

Star cluster NGC 6193 and nebula NGC 6188

This image, taken by OmegaCAM on the VLT Survey Telescope at Paranal Observatory, shows a section of the Ara OB1 stellar association. In the centre of the image is the young open cluster NGC 6193, and to the right is the emission nebula NGC 6188, illuminated by the ionising radiation emitted by the brightest nearby stars.

Sumber : ESO

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Quasars and Black Holes

An artist’s rendering of the most distant quasar

This artist’s impression shows how ULAS J1120+0641, a very distant quasar powered by a black hole with a mass two billion times that of the Sun, may have looked. This quasar is the most distant yet found and is seen as it was just 770 million years after the Big Bang. This object is by far the brightest object yet discovered in the early Universe.

Artist’s impression of cold intergalactic rain

The cosmic weather report, as illustrated in this artist’s concept, calls for condensing clouds of cold molecular gas around the Abell 2597 Brightest Cluster Galaxy. The clouds condense out of the hot, ionised gas that suffuses the space between the galaxies in this cluster. New ALMA data show that these clouds are raining in on the galaxy, plunging toward the supermassive black hole at its centre.

Supermassive black hole with torn-apart star

This artist’s impression depicts a rapidly spinning supermassive black hole surrounded by an accretion disc. This thin disc of rotating material consists of the leftovers of a Sun-like star which was ripped apart by the tidal forces of the black hole. Shocks in the colliding debris as well as heat generated in accretion led to a burst of light, resembling a supernova explosion.

Artist's impression of the surroundings of the supermassive black hole in NGC 3783

This artist’s impression shows the surroundings of the supermassive black hole at the heart of the active galaxy NGC 3783 in the southern constellation of Centaurus (The Centaur). New observations using the Very Large Telescope Interferometer at ESO’s Paranal Observatory in Chile have revealed not only the torus of hot dust around the black hole but also a wind of cool material in the polar regions.

Artist’s impression of the quasar 3C 279

This is an artist’s impression of the quasar 3C 279. Astronomers connected the Atacama Pathfinder Experiment (APEX), in Chile, to the Submillimeter Array (SMA) in Hawaii, USA, and the Submillimeter Telescope (SMT) in Arizona, USA for the first time, to make the sharpest observations ever, of the centre of a distant galaxy, the bright quasar 3C 279. Quasars are the very bright centres of distant galaxies that are powered by supermassive black holes. This quasar contains a black hole with a mass about one billion times that of the Sun, and is so far from Earth that its light has taken more than 5 billion years to reach us. The team were able to probe scales of less than a light-year across the quasar — a remarkable achievement for a target that is billions of light-years away.

Sumber : ESO

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Galaksi Nukleus

The Inner Part of an Active Galactic Nucleus

Artist's impression of an active galaxy that has jets. The central engine is thought to be a supermassive black hole surrounded by an accretion disc and enshrouded in a dusty doughnut-shaped torus. The torus of dust and gas can be seen orbiting a flatter disc of swirling gas. In the centre, the supermassive black hole is surrounded by a flat accretion disc of rapidly orbiting material. The jets are emitted at right angles from the plane of the disc. Courtesy Aurore Simonnet, Sonoma State University.

Radio Galaxy Centaurus A

The new FORS2 image of Centaurus A, also known as NGC 5128, is an example of how frontier science can be combined with esthetic aspects. This galaxy is a most interesting object for the present attempts to understand active galaxies. It is being investigated by means of observations in all spectral regions, from radio via infrared and optical wavelengths to X- and gamma-rays. It is one of the most extensively studied objects in the southern sky. FORS2, with its large field-of-view and excellent optical resolution, makes it possible to study the global context of the active region in Centaurus A in great detail. Note for instance the great number of massive and luminous blue stars that are well resolved individually, in the upper right and lower left in ESO Press Photo eso0005b. Centaurus A is one of the foremost examples of a radio-loud active galactic nucleus (AGN). On images obtained at optical wavelengths, thick dust layers almost completely obscure the galaxy's centre. This structure was first reported by Sir John Herschel in 1847. Until 1949, NGC 5128 was thought to be a strange object in the Milky Way, but it was then identified as a powerful radio galaxy and designated Centaurus A. The distance is about 10-13 million light-years (3-4 Mpc) and the apparent visual magnitude is about 8, or 5 times too faint to be seen with the unaided eye.There is strong evidence that Centaurus A is a merger of an elliptical with a spiral galaxy, since elliptical galaxies would not have had enough dust and gas to form the young, blue stars seen along the edges of the dust lane. The core of Centaurus A is the smallest known extragalactic radio source, only 10 light-days across. A jet of high-energy particles from this centre is observed in radio and X-ray images. The core probably contains a supermassive black hole with a mass of about 100 million solar masses.

This image is a composite of three exposures in B (300 sec exposure, image quality 0.60 arcsec; here rendered in blue colour), V (240 sec, 0.60 arcsec; green) and R (240 sec, 0.55 arcsec; red). The full-resolution version of this photo retains the original pixels.

The Centre of the Active Galaxy NGC 1097

Colour-composite image of the central 5,500 light-years wide region of the spiral galaxy NGC 1097, obtained with the NACO adaptive optics on the VLT. More than 300 star forming regions - white spots in the image - are distributed along a ring of dust and gas in the image. At the centre of the ring there is a bright central source where the active galactic nucleus and its super-massive black hole are located. The image was constructed by stacking J- (blue), H- (green), and Ks-band (red) images. North is up and East is to the left. The field of view is 24 x 29 arcsec2, i.e. less than 0.03% the size of the full moon!

A Galactic Embrace

Two galaxies, about 50 million light-years away, are locked in a galactic embrace — literally. The Seyfert galaxy NGC 1097, in the constellation of Fornax (The Furnace), is seen in this image taken with the VIMOS instrument on ESO’s Very Large Telescope (VLT). A comparatively tiny elliptical companion galaxy, NGC 1097A, is also visible in the top left. There is evidence that NGC 1097 and NGC 1097A have been interacting in the recent past.

Although NGC 1097 seems to be wrapping its companion in its spiral arms, this is no gentle motherly giant. The larger galaxy also has four faint jets — too extended and faint to be seen in this image — that emerge from its centre, forming an X-shaped pattern, and which are the longest visible-wavelength jets of any known galaxy. The jets are thought to be the remnants of a dwarf galaxy that was disrupted and cannibalised by the much larger NGC 1097 up to a few billion years ago.

These unusual jets are not the galaxy’s only intriguing feature. As previously mentioned, NGC 1097 is a Seyfert galaxy, meaning that it contains a supermassive black hole in its centre. However, the core of NGC 1097 is relatively faint, suggesting that the central black hole is not currently swallowing large quantities of gas and stars. Instead, the most striking feature of the galaxy’s centre is the ring of bright knots surrounding the nucleus. These knots are thought to be large bubbles of glowing hydrogen gas about 750–2500 light-years across, ionised by the intense ultraviolet light of young stars, and they indicate that the ring is a site of vigorous star formation

With this distinctive central star-forming ring, and the addition of numerous bluish clusters of hot, young stars dotted through its spiral arms, NGC 1097 makes a stunning visual object.

The data were originally taken in 2004 (see eso0438) with the VIMOS instrument on the VLT, and additional colour information from an image taken by amateur astronomer Robert Gendler has been superimposed. The VLT data were taken through three visible-light filters: R (at a wavelength of 652 nanometres, and shown here in red), V (a wavelength of 540 nanometres, shown in green), and B (456 nanometres, shown in blue). The image covers a region of approximately 7.7 x 6.6 arcminutes on the sky.

The Hidden Engine of NGC 4945

Portrayed in this image is the spiral galaxy NGC 4945, a close neighbour of the Milky Way. Belonging to the Centaurus A group of galaxies, it is located at a distance of almost 13 million light-years. Showing a remarkable resemblance to our own galaxy, NGC 4945 also hides a supermassive black hole behind the thick, ring-shaped structure of dust visible in the picture. But, unlike the black hole at the centre of our Milky Way, the million-solar-mass black hole inside NGC 4945 is an Active Galactic Nucleus that is frantically consuming any surrounding matter, and so releasing tremendous amounts of energy.

This image combines observations performed through three different filters (B, V, R) with the 1.5-metre Danish telescope at the ESO La Silla Observatory in Chile.

Sumber : ESO

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Galaksi Spiral

Spiral Galaxy NGC 300

This spectacular image of the large spiral galaxy NGC 1232 was obtained on September 21, 1998, during a period of good observing conditions. It is based on three exposures in ultra-violet, blue and red light, respectively. The colours of the different regions are well visible : the central areas contain older stars of reddish colour, while the spiral arms are populated by young, blue stars and many star-forming regions. Note the distorted companion galaxy on the left side, shaped like the greek letter "theta".

NGC 1232 is located 20º south of the celestial equator, in the constellation Eridanus (The River). The distance is about 100 million light-years, but the excellent optical quality of the VLT and FORS allows us to see an incredible wealth of details. At the indicated distance, the edge of the field shown corresponds to about 200,000 light-years, or about twice the size of the Milky Way galaxy.

The image is a composite of three images taken behind three different filters: U (360 nm; 10 min), B (420 nm; 6 min) and R (600 nm; 2:30 min) during a period of 0.7 arcsec seeing. The field shown measures 6.8 x 6.8 arcmin. North is up; East is to the left.

Antennae Galaxies composite

The Antennae Galaxies (also known as NGC 4038 and 4039) are a pair of distorted colliding spiral galaxies about 70 million light-years away, in the constellation of Corvus (The Crow). This view combines ALMA observations, made in two different wavelength ranges during the observatory’s early testing phase, with visible-light observations from the NASA/ESA Hubble Space Telescope.

The Hubble image is the sharpest view of this object ever taken and serves as the ultimate benchmark in terms of resolution. ALMA observes at much longer wavelengths which makes it much harder to obtain comparably sharp images. However, when the full ALMA array is completed its vision will be up to ten times sharper than Hubble.

Most of the ALMA test observations used to create this image were made using only twelve antennas working together — far fewer than will be used for the first science observations — and much closer together as well. Both of these factors make the new image just a taster of what is to come. As the observatory grows, the sharpness, speed, and quality of its observations will increase dramatically as more antennas become available and the array grows in size. This is nevertheless the best submillimetre-wavelength image ever taken of the Antennae Galaxies and opens a new window on the submillimetre Universe.

While visible light — shown here mainly in blue — reveals the newborn stars in the galaxies, ALMA’s view shows us something that cannot be seen at those wavelengths: the clouds of dense cold gas from which new stars form. The ALMA observations — shown here in red, pink and yellow — were made at specific wavelengths of millimetre and submillimetre light (ALMA bands 3 and 7), tuned to detect carbon monoxide molecules in the otherwise invisible hydrogen clouds, where new stars are forming.

Massive concentrations of gas are found not only in the hearts of the two galaxies but also in the chaotic region where they are colliding. Here, the total amount of gas is billions of times the mass of the Sun — a rich reservoir of material for future generations of stars. Observations like these will be vital in helping us understand how galaxy collisions can trigger the birth of new stars. This is just one example of how ALMA reveals parts of the Universe that cannot be seen with visible-light and infrared telescopes.

Spiral Galaxy NGC 4565

The first galaxy pictured here is NGC 4565, which for obvious reasons is also called the Needle Galaxy. First spotted in 1785 by Uranus' discoverer, Sir William Herschel (1738-1822), this is one of the most famous example of an edge-on spiral galaxy and is located some 30 million light-years away in the constellation Coma Berenices (Berenice's Hair). It displays a bright yellowish central bulge that juts out above most impressive dust lanes.

Because it is relatively close (it is only 12 times farther away than Messier 31, the Andromeda galaxy, which is the major galaxy closest to us) and relatively large (roughly one third larger than the Milky Way), it does not fit entirely into the field of view of the FORS instrument (about 7 x 7 arcmin2).

Many background galaxies are also visible in this FORS image, giving full meaning to their nickname of "island universes"

Spiral galaxy NGC 1232

This spectacular image of the large spiral galaxy NGC 1232 was obtained on September 21, 1998, during a period of good observing conditions. It is based on three exposures in ultra-violet, blue and red light, respectively. The colours of the different regions are well visible : the central areas contain older stars of reddish colour, while the spiral arms are populated by young, blue stars and many star-forming regions. Note the distorted companion galaxy on the left side, shaped like the greek letter "theta".

NGC 1232 is located 20º south of the celestial equator, in the constellation Eridanus (The River). The distance is about 100 million light-years, but the excellent optical quality of the VLT and FORS allows us to see an incredible wealth of details. At the indicated distance, the edge of the field shown corresponds to about 200,000 light-years, or about twice the size of the Milky Way galaxy.

The image is a composite of three images taken behind three different filters: U (360 nm; 10 min), B (420 nm; 6 min) and R (600 nm; 2:30 min) during a period of 0.7 arcsec seeing. The field shown measures 6.8 x 6.8 arcmin. North is up; East is to the left.

The Spiral Galaxy NGC 5584 and SN 2007af

This image is a colour-composite of the barred spiral galaxy NGC 5584. It is based on data collected by the Paranal Science Team with the FORS1 instrument on Kueyen, the second 8.2-m Unit Telescope of ESO's Very Large Telescope. The supernova SN 2007af is the bright object seen slightly below and to the right of the galaxy's centre. The galaxy and its bright supernova were observed on the nights of 16, 19 and 22 March 2007 through a B, V, R, H-alpha and OII filter. The total exposure time is about 28 minutes. The observers are Susana Randall, Claudio Melo and Swetlana Hubrig, and the day astronomer was Dominique Naef (all ESO). Henri Boffin (ESO) processed the data and made the colour-composite, and Haennes Heyer (ESO) made the final adjustments.

Sumber : ESO

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Galaksi dalam Tata surya

A Cosmic Embrace

Dalam gambar ini, dua galaksi spiral, mirip dalam penampilan dengan Bima Sakti, yang berpartisipasi dalam balet kosmik, yang, dalam beberapa miliar tahun, akan berakhir di merger galaksi lengkap - dua galaksi akan menjadi tunggal, satu lebih besar .

Terletak sekitar 150 juta tahun cahaya di konstelasi Canis Major (Great Dog), NGC 2207 - yang lebih besar dari dua - dan pendamping nya, IC 2163, membentuk pasangan yang megah. English astronom John Herschel menemukan mereka pada tahun 1835.

Daya tarik gravitasi fatal NGC 2207 sudah mendatangkan malapetaka di seluruh mitranya yang lebih kecil, distorsi bentuk IC 2163 dan melemparkan keluar bintang dan gas ke dalam pita panjang yang memperpanjang lebih dari 100.000 tahun cahaya. Ruang antara individu bintang di galaksi yang begitu luas, bagaimanapun, bahwa ketika galaksi ini bertabrakan, hampir tidak ada bintang-bintang di dalamnya akan benar-benar secara fisik menghancurkan satu sama lain.

Gambar ini diambil dengan ESO Faint Object Spectrograph dan Camera (EFOSC2) melalui tiga filter pita lebar (B, V, R). EFOSC2 memiliki medan 4,1 x 4,1 arcminute pandang dan melekat pada teleskop 3,6 meter di ESO La Silla Observatory di Chile.

NGC 300 X-1 in the spiral galaxy NGC 300

Para astronom menggunakan ESO Very Large Telescope (VLT) telah mendeteksi lubang hitam bintang-massa lebih jauh dari yang lain sebelumnya dikenal. Dengan massa sekitar dua puluh kali dari Matahari, ini juga merupakan lubang kedua yang paling besar bintang-massa hitam yang pernah ditemukan. Lubang hitam yang baru mengumumkan terletak pada sebuah galaksi spiral yang disebut NGC 300, enam juta tahun cahaya dari Bumi.

Gambar ini diperoleh dengan instrumen FORS2 pada VLT berpusat pada posisi lubang hitam. gambar mencakup bidang pandang sekitar 2x2 arcminutes, atau sekitar 4000 tahun cahaya pada jarak NGC 300. gambar berdasarkan data yang diperoleh melalui filter B lebar dan dua filter sempit-band berpusat pada 500 nm dan H- alfa.

Star cluster NGC 6193 and nebula NGC 6188

Gambar ini, diambil oleh OmegaCAM pada VLT Survey Telescope di Paranal Observatory, menunjukkan bagian dari Ara OB1 asosiasi bintang. Di tengah gambar adalah terbuka klaster muda NGC 6193, dan ke kanan adalah nebula emisi NGC 6188, diterangi oleh radiasi pengion yang dipancarkan oleh terang bintang di dekatnya.

Sumber : ESO

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