3
May 13

ALMA Pinpoints Early Galaxies at Record Speed

Credit ESO Science Release 1318

eso1318a
Image credits:ALMA (ESO/NAOJ/NRAO), J. Hodge et al., A. Weiss et al., NASA Spitzer Science Center

A team of astronomers has used the new ALMA (Atacama Large Millimeter/submillimeter Array) telescope to pinpoint the locations of over 100 of the most fertile star-forming galaxies in the early Universe. ALMA is so powerful that, in just a few hours, it captured as many observations of these galaxies as have been made by all similar telescopes worldwide over a span of more than a decade.(read more)

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6
Dec 12

Galaxy-wide Echoes from the Past

Source:ESO Science Release eso1249


The green bean galaxy J224.
Image credits:CFHT/ESO/M. Schirmer

A new galaxy class has been identified using observations from ESO’s Very Large Telescope (VLT), the Gemini South telescope, and the Canada-France-Hawaii Telescope (CFHT). Nicknamed “green bean galaxies” because of their unusual appearance, these galaxies glow in the intense light emitted from the surroundings of monster black holes and are amongst the rarest objects in the Universe. (read more)

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21
Nov 12

Planck spots hot gas bridging galaxy cluster pair

Source: ESA


Galaxy clusters connected by gas bridge.
Image credits: Sunyaev–Zel’dovich effect: ESA Planck Collaboration;
optical image: STScI Digitized Sky Survey

ESA’s Planck space telescope has made the first conclusive detection of a bridge of hot gas connecting a pair of galaxy clusters across 10 million light-years of intergalactic space.(read more)

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20
Nov 12

Fine-tuning galaxies with Herschel and Spitzer

Source: ESA


The Hubble Tuning Fork
Image credits: C. North, M. Galametz & the Kingfish Team

Galaxies come in all shapes and sizes: from those with compact fuzzy bulges or central bars to galaxies with winding spiral arms. Astronomer Edwin Hubble classified these different breeds of galaxies by means of a diagram known as the Hubble Tuning Fork.

The tuning fork shape presents elliptical galaxies along the handle, and two different populations of spiral galaxies on the fork’s ‘prongs’ to differentiate between spiral galaxies with a central bar, and those without.

The diagram also describes the shape of the galaxies. Elliptical galaxies are positioned further along the handle towards the fork depending on how elongated they appear, while spiral galaxies are organised by how tightly wound their arms are.

Of course, there are always exceptions, and a separate class of ‘irregular’ galaxies conforms to neither group, perhaps as a result of a collision or merging event disrupting their shape.

In this interactive tuning fork diagram, 61 nearby galaxies studied by ESA’s Herschel and NASA’s Spitzer space telescopes are presented. The galaxies are located 10–100 million light-years from Earth and were surveyed as part of two programmes: the Key Insights on Nearby Galaxies: a Far-Infrared Survey with Herschel (Kingfish) and the Spitzer Infrared Nearby Galaxies Survey (Sings).

Rather than stars, the images show dust between them that is gently heated by hot young stars, visible only to heat-seeking infrared telescopes such as Herschel and Spitzer.

Each individual image is a three-color composite showing warm dust (blue) detected by Spitzer at 24 microns, and cooler dust traced by Herschel at 100 microns (green) and 250 microns (red).

By clicking on each of the galaxies, more information is provided about their classification, distance, size and location in the sky.

The galaxies were chosen to cover a wide range of characteristics to improve our understanding of the processes linking star formation to the local interstellar environment in the nearby Universe.

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27
Oct 12

Monster galaxy may have been stirred up by black-hole mischief

Source: ESA/Hubble heic1216


Monster galaxy lacks a bright core.
Image credits: NASA, ESA, M. Postman (Space Telescope Science Institute, USA),
T. Lauer (National Optical Astronomy Observatory, USA), and the CLASH team.

Astronomers using the NASA/ESA Hubble Space Telescope have obtained a remarkable new view of a whopper of an elliptical galaxy, with a core bigger than any seen before. There are two intriguing explanations for the puffed up core, both related to the action of one or more black holes, and the researchers have not yet been able to determine which is correct. (read more)

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27
Sep 12

Hubble goes to the eXtreme to assemble the deepest ever view of the Universe

Source: ESA/Hubble heic1214


The Hubble eXtreme Deep Field .
Image credits: NASA, ESA, G. Illingworth, D. Magee, and
P. Oesch (University of California, Santa Cruz),
R. Bouwens (Leiden University), and the HUDF09 Team

 Like photographers assembling a portfolio of their best shots, astronomers have assembled a new, improved portrait of our deepest-ever view of the Universe. Called the eXtreme Deep Field, or XDF, the photo was assembled by combining ten years of NASA/ESA Hubble Space Telescope observations taken of a patch of sky within the original Hubble Ultra Deep Field. The XDF is a small fraction of the angular diameter of the full Moon.

The Hubble Ultra Deep Field is an image of a small area of space in the constellation of Fornax (The Furnace), created using Hubble Space Telescope data from 2003 and 2004. By collecting faint light over one million seconds of observation, the resulting image revealed thousands of galaxies, both nearby and very distant, making it the deepest image of the Universe ever taken at that time.

The new full-colour XDF image is even more sensitive than the original Hubble Ultra Deep Field image, thanks to the additional observations, and contains about 5500 galaxies, even within its smaller field of view. The faintest galaxies are one ten-billionth the brightness that the unaided human eye can see. (read more)

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25
Sep 12

Hubble portrays a dusty spiral galaxy

Source: ESA


The galaxy NGC4183.
Image credits: ESA/Hubble & NASA.

The NASA/ESA Hubble Space Telescope has provided us with another outstanding image of a nearby galaxy. This week, we highlight the galaxy NGC 4183, seen here with a beautiful backdrop of distant galaxies and nearby stars.

Located about 55 million light-years from the Sun and spanning about
80 000 light-years, NGC 4183 is a little smaller than the Milky Way. This galaxy, which belongs to the Ursa Major Group, lies in the northern constellation of Canes Venatici (The Hunting Dogs).

NGC 4183 is a spiral galaxy with a faint core and an open spiral structure. Unfortunately, this galaxy is viewed edge-on from Earth, and we cannot fully appreciate its spiral arms. But we can admire its galactic disc. (read more)

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2
Aug 12

A Blue Whirlpool in The River — Tranquil galaxy home to violent events

Source: ESO Photo Release eso1231


VLT image of the spiral galaxy NGC 1187.
Image credit: ESO

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.(read more)

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12
Jul 12

Dark Galaxies of the Early Universe Spotted for the First Time

Source: ESO Science Release eso1228


Dark galaxies spotted for the first time.
Image credits: ESO, Digitized Sky Survey 2 and S. Cantalupo (UCSC)

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.(read more)

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11
Jul 12

Hubble Unmasks Ghost Galaxies

Source: ESA/Hubble


500 000 light-years from Earth, Leo IV is one of more than a dozen ultra-faint dwarf galaxies found lurking around our Milky Way galaxy.
Image credits: NASA, ESA, and T. Brown (STScI)

Astronomers have used the NASA/ESA Hubble Space Telescope to study some of the smallest and faintest galaxies in our cosmic neighbourhood. These galaxies are fossils of the early Universe: they have barely changed for 13 billion years. The discovery could help explain the so-called “missing satellite” problem, where only a handful of satellite galaxies have been found around the Milky Way, against the thousands that are predicted by theories. (read more)

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3
Jun 12

ALMA Turns its Eyes to Centaurus A

Source: ESO Photo Release eso1222


New image of Centaurus A.
Image credits: ALMA (ESO/NAOJ/NRAO); ESO/Y. Beletsky.

A new image of the centre of the distinctive galaxy Centaurus A, made with the Atacama Large Millimeter/submillimeter Array (ALMA), shows how the new observatory allows astronomers to see through the opaque dust lanes that obscure the galaxy’s centre, with unprecedented quality. ALMA is currently in its Early Science phase of observations and is still under construction, but is already the most powerful telescope of its kind. The observatory has just issued the Call for Proposals for its next cycle of observations, in which the growing telescope will have increased capabilities. (read more)

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1
Jun 12

Milky Way vs. Andromeda: A Titanic collision

Source: NASA


Milky Way and Andromeda are moving toward each other.
Image credit: NASA; ESA; A. Feild and R. van der Marel, STScI.

NASA astronomers announced today they can now predict with certainty the next major cosmic event to affect our galaxy, sun, and solar system: the titanic collision of our Milky Way galaxy with neighboring Andromeda.(read more)

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16
May 12

A Deeper Look at Centaurus A

Source: ESO Photo Release eso122


The peculiar galaxy Centaurus A (NGC 5128).
Image credits: ESO.

The strange galaxy Centaurus A is pictured in a new image from the European Southern Observatory. With a total exposure time of more than 50 hours this is probably the deepest view of this peculiar and spectacular object ever created. The image was produced by the Wide Field Imager of the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile.(learn more)

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25
Apr 12

Spitzer Space Telescope Finds Galaxy with Split Personality

Source: NASA Press Release


The Sombrero galaxy is not simply a regular flat disk galaxy of stars as previously believed.
Image credit: NASA/JPL-Caltech

 

While some galaxies are rotund and others are slender disks like our spiral Milky Way, new observations from NASA's Spitzer Space Telescope show that the Sombrero galaxy is both. The galaxy, which is a round, elliptical with a thin disk embedded inside, is one of the first known to exhibit characteristics of the two different types. The findings will lead to a better understanding of galaxy evolution, a topic still poorly understood.

"The Sombrero is more complex than previously thought," said Dimitri Gadotti of the European Southern Observatory in Chile and lead author of a new paper on the findings appearing in the Monthly Notices of the Royal Astronomical Society. "The only way to understand all we know about this galaxy is to think of it as two galaxies, one inside the other."

The Sombrero galaxy, also known as NGC 4594, is located 28 million light-years away in the constellation Virgo. From our viewpoint on Earth, we can see the thin edge of its flat disk and a central bulge of stars, making it resemble a wide-brimmed hat. Astronomers do not know whether the Sombrero's disk is shaped like a ring or a spiral, but agree it belongs to the disk class.

"Spitzer is helping to unravel secrets behind an object that has been imaged thousands of times," said Sean Carey of NASA's Spitzer Science Center at the California Institute of Technology in Pasadena, Calif. "It is intriguing Spitzer can read the fossil record of events that occurred billions of years ago within this beautiful and archetypal galaxy."

Spitzer captures a different view of the galaxy than visible-light telescopes. In visible views, the galaxy appears to be immersed in a glowing halo, which scientists had thought was relatively light and small. With Spitzer's infrared vision, a different view emerges. Spitzer sees old stars through the dust and reveals the halo has the right size and mass to be a giant elliptical galaxy.

While it is tempting to think the giant elliptical swallowed a spiral disk, astronomers say this is highly unlikely because that process would have destroyed the disk structure. Instead, one scenario they propose is that a giant elliptical galaxy was inundated with gas more than nine billion years ago. Early in our universe, networks of gas clouds were common, and they sometimes fed growing galaxies, causing them to bulk up. The gas would have been pulled into the galaxy by gravity, falling into orbit around the center and spinning out into a flat disk. Stars would have formed from the gas in the disk.

"This poses all sorts of questions," said Rubén Sánchez-Janssen from the European Southern Observatory, co-author of the study. "How did such a large disk take shape and survive inside such a massive elliptical? How unusual is such a formation process?"

Researchers say the answers could help them piece together how other galaxies evolve. Another galaxy, called Centaurus A, appears also to be an elliptical galaxy with a disk inside it. But its disk does not contain many stars. Astronomers speculate that Centaurus A could be at an earlier stage of evolution than the Sombrero and might
eventually look similar.

The findings also answer a mystery about the number of globular clusters in the Sombrero galaxy. Globular clusters are spherical nuggets of old stars. Ellipticals typically have a few thousand, while spirals contain a few hundred. The Sombrero has almost 2,000, a number that makes sense now but had puzzled astronomers when they thought it was only a disk galaxy.

For more information about Spitzer, visit:
http://www.nasa.gov/spitzer

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14
Mar 12

The feeding habits of teenage galaxies

Source: ESO Science Release eso1212


Galaxies in a deep view of a tiny patch of sky in the constellation of Cetus.
Image credits: ESO/CFHT

New observations made with ESO’s Very Large Telescope are making a major contribution to understanding the growth of adolescent galaxies. In the biggest survey of its kind astronomers have found that galaxies changed their eating habits during their teenage years - the period from about 3 to 5 billion years after the Big Bang. At the start of this phase smooth gas flow was the preferred snack, but later, galaxies mostly grew by cannibalising other smaller galaxies. (read more)

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24
Feb 12

Spitzer finds solid Buckyballs in Space

Source: NASA Spitzer


NASA's Spitzer Space Telescope has detected little spheres of
carbon, called buckyballs, in the Small Magellanic Cloud.
Image credits: NASA/JPL-Caltech.

Astronomers using data from NASA's Spitzer Space Telescope have, for the first time, discovered buckyballs in a solid form in space. Prior to this discovery, the microscopic carbon spheres had been found only in gas form.

Formally named buckminsterfullerene, buckyballs are named after their resemblance to the late architect Buckminster Fuller's geodesic domes. They are made up of 60 carbon molecules arranged into a hollow sphere, like a soccer ball. Their unusual structure makes them ideal candidates for electrical and chemical applications on Earth, including superconducting materials, medicines, water purification and armor.

In the latest discovery, scientists using Spitzer detected tiny specks of matter, or particles, consisting of stacked  buckyballs. They found them around a pair of stars called "XX Ophiuchi," 6,500 light-years from Earth. (read more)

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17
Feb 12

Hubble finds relic of a shredded galaxy

Source: ESA/Hubble Science Release heic1203


Star cluster surrounds wayward black hole in cannibal galaxy ESO 243-49.
Image credits: NASA, ESA, and S. Farrell (University of Sydney, Australia and University of Leicester, UK).

Astronomers using the NASA/ESA Hubble Space Telescope have found a cluster of young blue stars surrounding a mid-sized black hole called HLX-1. The discovery suggests that the black hole formed in the core of a now-disintegrated dwarf galaxy. The findings have important implications for understanding the evolution of supermassive black holes and galaxies. (read more)

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6
Feb 12

NGC 1073 - Classic Portrait of a Barred Spiral Galaxy

Source: ESA/Hubble Photo Release heic1202


Barred spiral galaxy NGC 1073. Image credits: NASA & ESA.

The NASA/ESA Hubble Space Telescope has taken a picture of the barred spiral galaxy NGC 1073, which is found in the constellation of Cetus (The Sea Monster). Our own galaxy, the Milky Way, is a similar barred spiral, and the study of galaxies such as NGC 1073 helps astronomers learn more about our celestial home. (read more)

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18
Dec 11

A Galaxy Blooming with New Stars — VLT Survey Telescope snaps wide-field view of NGC 253

Source: ESO Photo Release eso1152


Wide-field view of NGC 253 from the VLT Survey Telescope.
Image credits: ESO/INAF-VST.

The VLT Survey Telescope (VST) has captured the beauty of the nearby spiral galaxy NGC 253. The new portrait is probably the most detailed wide-field view of this object and its surroundings ever taken. It demonstrates that the VST, the newest telescope at ESO's Paranal Observatory, provides broad views of the sky while also offering impressive image sharpness.(read more)

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18
Nov 11

Hubble observes young dwarf galaxies bursting with stars

Source: NASA


18 tiny galaxies discovered by Hubble Space Telescope.
Image credits: NASA, ESA, A. van der Wel (Max Planck Institute for Astronomy, Heidelberg, Germany), H. Ferguson and A. Koekemoer (STScI.), and the CANDELS team.

Using its near-infrared vision to peer 9 billion years back in time, NASA's Hubble Space Telescope has uncovered an extraordinary population of young dwarf galaxies brimming with star formation. While dwarf galaxies are the most common type of galaxy in the universe, the rapid star-birth observed in these newly found examples may force astronomers to reassess their understanding of the ways in which galaxies form. (read more)

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