Galaxy Cluster CLASS B1608+656

An image of a galaxy cluster taken by the NASA/ESA Hubble Space Telescope gives a remarkable cross-section of the Universe, showing objects at different distances and stages in cosmic history. They range from cosmic near-neighbors to objects seen in the early years of the Universe. The 14-hour exposure shows objects around a billion times fainter than can be seen with the naked eye.

Hubble's images might look flat, but this one shows a remarkable depth of field that lets us see more than halfway to the edge of the observable Universe. Most of the galaxies visible here are members of a huge cluster called CLASS B1608+656, which lies about five billion light-years away. But the field also contains other objects, both significantly closer and far more distant, including quasar QSO-160913+653228 which is so distant its light has taken nine billion years to reach us, two-thirds of the time that has elapsed since the Big Bang.

Photo credit: NASA, ESA

Note: For more information, see A Cross-Section of the Universe.

Quasar RX J1131-1231

RX J1131-1231: A quasar located about 6 billion light years from Earth.

Multiple images of a distant quasar known as RX J1131-1231 are visible in this combined view from Chandra (pink) and Hubble (red, green, and blue). The Chandra data, along with data from ESA’s XMM-Newton, were used to directly measure the spin of the supermassive black hole powering this quasar. Black holes are defined by just two simple characteristics: mass and spin. At a distance of 6 billion light years, this is the most distant black hole where such a measurement has been made, allowing for an important advance in understanding how black holes grow over time.

Scale: Image is 1.2 arcmin across (about 1.6 million light years).

Image credit: X-ray: NASA/CXC/Univ of Michigan/R.C.Reis et al; Optical: NASA/STScI

Note: For more information, see RX J1131-1231: Chandra & XMM-Newton Provide Direct Measurement of Distant Black Hole's Spin.

Tracing the Origin of the Magellanic Stream

These images show wide and close-up views of a long ribbon of gas called the Magellanic Stream, which stretches nearly halfway around the Milky Way.

In the combined radio and visible-light image at the top, the gaseous stream is shown in pink. The radio observations from the Leiden/Argentine/Bonn (LAB) Survey have been combined with the Mellinger All-Sky Panorama in visible light. The Milky Way is the light blue band in the center of the image. The brown clumps are interstellar dust clouds in our galaxy. The Magellanic Clouds, satellite galaxies of the Milky Way, are the white regions at the bottom right.

The image at the bottom, taken at radio wavelengths, is a close-up map of the Magellanic Stream that also was generated from the LAB Survey. Researchers determined the chemistry of the gas filament by using Hubble's Cosmic Origins Spectrograph (COS) to measure the amount of heavy elements, such as oxygen and sulfur, at six locations (marked with an "x") along the Magellanic Stream. COS observed light from faraway quasars that passed through the stream, and detected the spectral fingerprints of these elements from the way they absorb ultraviolet light. Quasars are the brilliant cores of active galaxies.

These observations show that most of the gas was stripped from the Small Magellanic Cloud about two billion years ago – but surprisingly, a second region of the stream was formed more recently from the Large Magellanic Cloud. The pink circles to the right mark the location of the Small and Large Magellanic Clouds.

Image credits: Credit for the radio/visible light image: David L. Nidever, et al., NRAO/AUI/NSF and Mellinger, LAB Survey, Parkes Observatory, Westerbork Observatory, and Arecibo Observatory. Credit for the radio image: LAB Survey.

Note: For more information, see Hubble finds source of Magellanic Stream - Astronomers Explore Origin of Gas Ribbon Wrapped Around Our Galaxy.

Artist’s Impression of a Galaxy Accreting Material from its Surroundings

This artist’s impression shows a galaxy in the distant Universe, just two billion years after the Big Bang, in the process of pulling in cool gas (shown in orange) from its surroundings. Astronomers have been able to find out a lot about this object by studying not just the galaxy, but also the light of a much more distant quasar (the bright object to the left of the central galaxy), which happens to be in the right place to shine through the accreting gas. The motions of the gas and its composition fit very well with theories of cool gas accretion as a way of feeding star formation and galaxy growth.

Illustration credit: ESO/L. Calçada/ESA/AOES Medialab

Note: For more information, see Feeding Galaxy Caught in Distant Searchlight.

Quasar GB 1428+4217: Furthest X-Ray Jet Detected

GB 1428+4217: A quasar at a distance of about 12.4 billion light years from Earth.

This composite image shows GB 1428+4217, a quasar that contains the most distant X-ray jet ever observed. This view contains X-rays from Chandra (blue), radio data from the Very Large Array (purple), and optical data from Hubble (yellow). The jet, whose shape is very similar in the X-ray and radio data, was produced by a giant black hole, at the center of a galaxy, pulling in matter at a rapid rate. The energy released as particles fall toward the black hole generates intense radiation and powerful beams of high-energy particles that blast away from the black hole at nearly the speed of light. GB 1428+4217 is located about 12.4 billion light years from Earth, surpassing the distance of previously discovered X-ray jets.

Scale: Image is 41 arcsec across. (about 900,000 light years).

Image credit: X-ray: NASA/CXC/NRC/C.Cheung et al; Optical: NASA/STScI; Radio: NSF/NRAO/VLA

Note: For more information, see GB 1428+4217: Record-Setting X-ray Jet Discovered.

Material Ejected from Quasar SDSS J1106+1939

This artist’s impression shows the material ejected from the region around the supermassive black hole in the quasar SDSS J1106+1939. This object has the most energetic outflows ever seen, at least five times more powerful than any that have been observed to date. Quasars are extremely bright galactic centers powered by supermassive black holes. Many blast huge amounts of material out into their host galaxies, and these outflows play a key role in the evolution of galaxies. But, before this object was studied, the observed outflows weren’t as powerful as predicted by theorists. The very bright quasar appears at the center of the picture and the outflow spreads about 1000 light-years out into the surrounding galaxy.

Illustration credit: ESO/L. Calçada

Note: For more information, see Biggest Black Hole Blast Discovered.

Artist's Conception of 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 center of a distant galaxy, the bright quasar 3C 279. Quasars are the very bright centers 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.

Illustration credit: ESO/M. Kornmesser

Note: For more information, see APEX Takes Part in Sharpest Observation Ever.

Dark Galaxies Spotted for the First Time

This deep image shows the region of the sky around the quasar HE0109-3518. The quasar is labeled with a red circle near the center of the image. The energetic radiation of the quasar makes dark galaxies glow, helping astronomers to understand the obscure early stages of galaxy formation. The faint images of the glow from 12 dark galaxies are labeled with blue circles. Dark galaxies are essentially devoid of stars, therefore they don’t emit any light that telescopes can catch. This makes them virtually impossible to observe unless they are illuminated by an external light source like a background quasar.

This image combines observations from the Very Large Telescope, tuned to detect the fluorescent emissions produced by the quasar illuminating the dark galaxies, with color data from the Digitized Sky Survey 2.

Photo credit: ESO, Digitized Sky Survey 2 and S. Cantalupo (UCSC)

Note: For more information, see Dark Galaxies of the Early Universe Spotted for the First Time. An unannotated version of this image may be found here.

Distant, Obscured Quasars

The galaxies pictured here have so much dust surrounding them that the brilliant light from their quasars cannot be seen in these images from NASA's Hubble Space Telescope.

Quasars are the brilliant beacons of light that are powered by black holes feasting on captured material, and in the process, heating some of the matter to millions of degrees.

The galaxies are part of a census of 30 quasar host galaxies conducted with two of NASA's premier observatories, the Hubble Space Telescope and Spitzer Space Telescope. They were found in the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). The study shows that 26 of the host galaxies bear no telltale signs of collisions with neighbors, such as distorted shapes.

The quasars found in normal-looking galaxies are fainter than those powered by collisions between galaxies, which send lots of gas and dust into the gravitational whirlpool of hungry black holes. The dimmer quasars are triggered by black holes snacking on such tasty treats as a batch of gas or the occasional small satellite galaxy. They are the most abundant type of quasar, according to the Hubble analysis.

The images at top right, bottom left, and bottom right reveal three of the survey's normal-looking galaxies that host quasars. Only one galaxy in the sample, at top left, shows evidence of an interaction with another galaxy. The two white blobs are the cores from both galaxies. A streamer of material, colored brown and blue, also lies below the merging galaxies.

The galaxies existed roughly 8 billion to 12 billion years ago, during a peak epoch of black-hole growth. The galaxies' masses are comparable to our Milky Way's. The blue patches are star-forming regions. The brown areas are either dust or old stars.

The images were taken by Hubble's Wide Field Camera 3 between 2011 and 2012.

Photo credit: NASA/ESA/Yale

Gravitational Lensing by Quasars

In space, it sometimes happens that two galaxies are aligned in just the right way that the closer galaxy distorts and magnifies the appearance of the one behind it. For astronomers, finding these alignments is like coming across giant, cosmic magnifying glasses.

Now, a team of astronomers, including Daniel Stern from NASA's Jet Propulsion Laboratory in Pasadena, California, has found several rare examples of this phenomenon, called gravitational lensing, in which the foreground galaxy hosts an actively accreting supermassive black hole.

Such feeding black holes, called quasars, are among the brightest objects in the universe, far outshining the total starlight of their host galaxies. Because they are so bright, it is hard for astronomers to measure the mass of their host galaxies. However, gravitational lenses are invaluable for estimating the mass of a quasar's host galaxy. The amount of the background galaxy's distortion can be used to accurately measure the lensing galaxy's mass.

The team hopes to build an even bigger catalog of these quasar lenses, and to use these data to better understand the interplay between black hole feeding and star formation in galaxy evolution.

Photo credit: NASA, ESA, EPFL (Switzerland); text credit: NASA/JPL.

Note: For more information, see Astronomers Using NASA's Hubble Discover Quasars Acting as Gravitational Lenses; for more images, see PIA15418: Quasar Lenses.

Gravitationally Lensed Quasar HE 1104-1805

This picture shows a quasar that has been gravitationally lensed by a galaxy in the foreground, which can be seen as a faint shape around the two bright images of the quasar.

Observations of one of the images show variations in color over time. This is caused by stars within the lens galaxy passing through the path of the light from the quasar, magnifying the light from different parts of the quasar's accretion disc as they move. This has allowed a team of scientists to reconstruct the color and temperature profile of the accretion disc with unprecedented precision. The level of detail involved is equivalent to being able to study individual grains of sand on the surface of the Moon while standing on Earth.

Photo credit: NASA, ESA and J.A. Muñoz (University of Valencia)

Note: For more information, see Hubble Directly Observes the Disc Around a Black Hole.

Cygnus X-1

This illustration depicts the X-ray binary Cygnus X-1, composed of a 35 Msun blue O9 supergiant star and a black hole with a mass of about 10 Msun.

With its intense gravitational field, the black hole draws matter from its companion, and the stripped material spirals around the black hole, forming an accretion disc. Friction in the disc heats the material up to millions of degrees, making it shine in X-rays. Furthermore, the rotation of the disc funnels part of the accreted material into highly collimated, bipolar jets of particles that are released at relativistic speeds.

Based on the existing link between accretion and ejection of matter in X-ray binaries, astronomers also refer to these objects as 'microquasars' because they appear as miniature versions of quasars - the nuclei of active galaxies.

Illustration credit: ESA

Note: "Msun" means "solar mass," the mass of our sun. It is a common measurement to compare the sizes of stars. For more information, see INTEGRAL Discovers Gamma Rays Originating From Black Hole Jets.

Galaxy Cluster 3C 186

3C186: A galaxy cluster with a central quasar located about 8 billion light years away.

This composite image contains a new, deep image from Chandra (blue) showing emission from gas surrounding the point-like quasar near the center of the galaxy cluster known as 3C 186. Optical data from the Gemini telescope (yellow) show the stars and galaxies in the field of view. Chandra X-ray spectra reveal that the temperature of the gas drops from 80 million degrees on the outskirts of the cluster down to 30 million in the core. This drop in temperature occurs because intense X-ray emission from the gas cools it. 3C 186 is the most distant such object observed, and could provide insight into the triggering of quasars and the growth of galaxy clusters.

Scale: Image is 4.6 by 3.4 arcminutes (10.7 by 7.9 million light years).

Photo credit: X-ray: NASA/CXC/SAO/A.Siemiginowska et al, Optical: AURA/Gemini Observatory

Note: More information and photos can be found at 3C186: Precocious Galaxy Cluster Identified by Chandra.