European Association for Astronomy Education

Source: ESO Science Release eso1519

This huge elliptical galaxy NGC 5128 (also known as Centaurus A) is the closest such galaxy to the Earth, at a distance of about 12 million light-years. Observations with ESO’s Very Large Telescope in Chile have discovered a new class of “dark” globular star clusters around this galaxy. These are marked in red. Normal globulars are marked in blue and globulars showing similar properties to dwarf galaxies are in green. The dark globulars appear very similar to other globulars around this galaxy but contain much more mass. Image credits: ESO/Digitized Sky Survey. Acknowledgement: Davide de Martin

Observations with ESO’s Very Large Telescope in Chile have discovered a new class of “dark” globular star clusters around the giant galaxy Centaurus A. These mysterious objects look similar to normal clusters, but contain much more mass and may either harbour unexpected amounts of dark matter, or contain massive black holes — neither of which was expected nor is understood. (read more)

Source: ESA/Hubble Science Release heic1510

Globular cluster 47 Tucanae.
Image credits: NASA, ESA, and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration
Acknowledgment: J. Mack (STScI) and G. Piotto (University of Padova, Italy)

Astronomers using the NASA/ESA Hubble Space Telescope have, for the first time, collected a census of young white dwarf stars beginning their migration from the crowded centre of an ancient star cluster to its less populated outskirts. The new results challenge our ideas about how and when a star loses its mass near the end of its life. (read more)

Source: ESO

The star cluster NGC 3766. Image credit: ESO.

Astronomers using the Swiss 1.2-metre Euler telescope at ESO’s La Silla Observatory in Chile have found a new type of variable star. The discovery was based on the detection of very tiny changes in brightness of stars in a cluster. The observations revealed previously unknown properties of these stars that defy current theories and raise questions about the origin of the variations. (read more)

Source: ESO Science Release eso1323

The globular star cluster NGC 6752.
Image credits: ESO.

Astronomers expect that stars like the Sun will blow off much of their atmospheres into space near the ends of their lives. But new observations of a huge star cluster made using ESO’s Very Large Telescope have shown — against all expectations — that a majority of the stars studied simply did not get to this stage in their lives at all. The international team found that the amount of sodium in the stars was a very strong predictor of how they ended their lives. (read more)

Source: ESO Photo Release eso1243

The globular star cluster NGC 6362.
Image credit: ESO.

This colourful view of the globular star cluster NGC 6362 was captured by the Wide Field Imager attached to the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile. This new picture, along with a new image of the central region from the NASA/ESA Hubble Space Telescope, provide the best view of this little-known cluster ever obtained. Globular clusters are mainly composed of tens of thousands of very ancient stars, but they also contain some stars that look suspiciously young. (read more)

Source: ESO Photo Release eso1235

Globular star cluster Messier 4.
Image credits:ESO. Acknowledgement: ESO Imaging Survey.

A new image from ESO’s La Silla Observatory in Chile shows the spectacular globular star cluster Messier 4. This ball of tens of thousands of ancient stars is one of the closest and most studied of the globular clusters and recent work has revealed that one of its stars has strange and unexpected properties, apparently possessing the secret of eternal youth. (read more)

Source: ESO Photo Release eso1141

VISTA view of the globular cluster VVV CL001 and its companion
Image credits: ESO/D. Minniti/VVV Team.

Two newly discovered globular clusters have been added to the total of just 158 known globular clusters in our Milky Way. They were found in new images from ESO’s VISTA survey telescope as part of the Via Lactea (VVV) survey. This survey has also turned up the first star cluster that is far beyond the centre of the Milky Way and whose light has had to travel right through the dust and gas in the heart of our galaxy to get to us.(read more)

Source: YouTube

A fabulous video of Comet Garradd passing the globular cluster M71 done by Bareket observatory, Israel.

Source: ESO Organisation Release eso1119

VST image of the star-forming region Messier 17.
Image credit: ESO/INAF-VST/OmegaCAM.
Acknowledgement: OmegaCen/Astro-WISE/Kapteyn Institute.

The VLT Survey Telescope (VST), the latest addition to ESO’s Paranal Observatory, has made its first release of impressive images of the southern sky. The VST is a state-of-the-art 2.6-metre telescope, with the huge 268-megapixel camera OmegaCAM at its heart, which is designed to map the sky both quickly and with very fine image quality. It is a visible-light telescope that perfectly complements ESO’s VISTA infrared survey telescope. New images of the Omega Nebula and the globular cluster Omega Centauri demonstrate the VST’s power. (read more)

Source: ESO Science Release eso1108

The most remote mature cluster of galaxies yet found.
Credit: ESO/NOAJ/Subaru/R. Gobat

Astronomers have used an armada of telescopes on the ground and in space, including the Very Large Telescope at ESO’s Paranal Observatory in Chile to discover and measure the distance to the most remote mature cluster of galaxies yet found. Although this cluster is seen when the Universe was less than one quarter of its current age it looks surprisingly similar to galaxy clusters in the current Universe. (read more)

Source: ESO Photo Release eso1048

Globular cluster Messier 107, also known as NGC 6171, located about 21 000 light-years away in the constellation of Ophiuchus.
Image credit: ESO/ESO Imaging Survey

About 150 of the rich collections of old stars called globular clusters are known to orbit our galaxy, the Milky Way. This sharp new image of Messier 107, captured by the Wide Field Imager on the 2.2-meter telescope at ESO’s La Silla Observatory in Chile, displays the structure of one such globular cluster in exquisite detail. Studying these stellar swarms has revealed much about the history of our galaxy and how stars evolve. (read more)

Source: arXiv

In the last decade the advent of new types of dwarf stellar systems became a reality.

The new dwarf stellar systems include ultra-compact dwarfs, ultra-faint dwarf spheroidals, and exotic globular clusters, breaking the old simple paradigm for dwarf galaxies and globular clusters. These objects become more intriguing, and understanding of these new findings becomes more challenging. Recently we discovered a new type of large scale structure in the Virgo cluster of galaxies: it is composed of globular clusters. Globular clusters in Virgo are found wandering between galaxies (intraclus- ter globular clusters) as well as in galaxies.

The Virgo Galaxy Cluster. Source:DSS.

These intracluster globular clusters fill a significant fraction in the area of the Virgo cluster and they are dominated by blue globular clusters. These intracluster globular clusters may be closely related with the first dwarf galaxies in the universe. (read the full pdf article from arXiv)