Starship Asterisk*

Image Credit: ESO/Vincenzo Forchi

---

This photograph, taken by Vincenzo Forchi, provides a unique insight into one of ESO’s most famous — and hard-working — residents. This cacophony of colour, structure and machinery is the interior of the 8.2-metre Unit Telescope 1 (UT1) of ESO’s Very Large Telescope (VLT), at Paranal Observatory in northern Chile. UT1 is more charmingly named Antu, which means The Sun in the region’s indigenous Mapuche language. The other UTs are named after the Moon, the Southern Cross, and Venus — Kueyen, Melipal, and Yepun respectively.

Forchi’s image shows Antu as it blinks open its high-tech eye and prepares for a long night observing the cosmos. At the base of the building, artificial lights bathe the area with an incandescent yellow glow. Above, the blue and silver hues of the telescope’s metalwork are complemented by the warm orange embrace of the Sun’s final rays, which scatter off the numerous flaps, or louvres, that encircle the enclosure.

Vincenzo submitted this photograph to the Your ESO Pictures Flickr group. The Flickr group is regularly reviewed and the best photos are selected to be featured in our popular Picture of the Week series.

Image Credit: ESA/Hubble & NASA

---

At first glance, it may seem as though this image was taken through a faulty lens, but the mind-bending distortions visible in this Hubble Wide Field Camera 3 impressive image are actually caused by a cosmic phenomenon.

The bright object at the centre of the frame is the galaxy cluster SDSS J1336-0331. The enormous gravitational influence of the cluster warps the very shape and fabric of its environment (the spacetime around it) creating an effect known as strong gravitational lensing. Through this the light from background galaxies in the line of sight to the observer are bent into fantastic arcs. This effect is very useful for studying distant background galaxies.

Moreover SDSS J1336-0331 is interesting in itself: the cluster was part of a study of star formation within 42 of the Brightest Cluster Galaxies (BCGs — the brightest galaxies within their host clusters, as the name would suggest). Typically located in the centres of their clusters, BCGs are among the most massive and luminous galaxies in the Universe. They are generally huge elliptical galaxies and are likely to host active galactic nuclei (AGN) in their cores. The study found evidence to suggest that BCGs are fueled by cold gas from the galaxy. It also showed that star formation in older BCGs no longer significantly contributes to the galaxy’s growth; instead, the stellar growth occurs through mergers, the collision of two galaxies. Violent, gas-rich major mergers can trigger intense bursts of star formation in their aftermath.

starsurfer wrote: ↑Mon Jul 23, 2018 12:03 pm NGC 3184
http://astro-koop.de/?attachment_id=1967
Copyright: Stefan Heutz, Wolfgang Ries and Michael Breite

Click to view full size image

Image Credit: Yuri Beletsky (LCO) / ESO

---

This image shows a number of antennas from the Atacama Large Millimeter/submillimeter Array (ALMA), a state-of-the-art telescope array positioned high in the Chilean Andes. A full Moon can be seen above the red-tinted horizon, glowing brightly above the observatory.

ALMA sits on the Chajnantor Plateau, some 5000 metres above sea level. At this altitude, crystal-clear views of the cosmos can be seen on an almost nightly basis, as shown by the striking cosmic caterpillar gliding over the top of the ALMA antennas in this image. This bright streak is the Milky Way; the galaxy’s bulge of gas and intricate dust lanes is clearly illuminated against the star-studded night sky, with pink-hued patches marking areas of hot, ionised gas produced by newly formed stars. The brightest part of the Milky Way — the very heart of our galaxy — is situated approximately 25 000 light-years away from Earth.

Credit: ESA/Hubble & NASA -- Acknowledgement: Judy Schmidt

---

This image taken by the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 (WFC3) shows a beautiful spiral galaxy called NGC 6744. At first glance, it resembles our Milky Way albeit larger, measuring more than 200 000 light-years across compared to 100 000 light-year diameter for our home galaxy.

NGC 6744 is similar to our home galaxy in more ways than one. Like the Milky Way, NGC 6744 has a prominent central region packed with old yellow stars. Moving away from the galactic core, one can see parts of the dusty spiral arms painted in shades of pink and blue; while the blue sites are full of young star clusters, the pink ones are regions of active star formation, indicating that the galaxy is still very lively.

In 2005, a supernova, named 2005at, was discovered within NGC 6744, adding to the argument of this galaxy’s liveliness (not visible in this image). SN 2005at is a type Ic supernova, formed when a massive star collapses in itself and loses its hydrogen envelope.

Ann wrote: ↑Mon Jul 23, 2018 3:07 pm

starsurfer wrote: ↑Mon Jul 23, 2018 12:03 pm NGC 3184
http://astro-koop.de/?attachment_id=1967
Copyright: Stefan Heutz, Wolfgang Ries and Michael Breite

Click to view full size image

NGC 3184 is a nice galaxy! And I like the picture. It brings home the message that the galaxy is mostly blue, but the yellow center of it is much, much brighter than its blue arms.

Ann

Credit: ESO/VST

---

This ESO Picture of the Week shows a crescent-shaped cocoon of gas and dust — a nebula known as NGC 3199, which lies 12 000 light-years away from Earth. It appears to plough through the star-studded sky like a ship through stormy seas. This imagery is very appropriate due to NGC 3199’s location in Carina — a southern constellation which is named after the keel of a ship!

NGC 3199 was discovered by British astronomer John Herschel in 1834 as he compiled his famous catalogue of interesting night sky objects. The nebula has been the subject of numerous observations since, including those by ESO’s 8.2-metre Very Large Telescope (VLT) (eso0310, eso1117), and 2.6-metre VLT Survey Telescope (VST). The latter made the observations that comprise this image. The nebula’s bright crescent feature is now known to be part of a much larger but fainter bubble of gas and dust.

The nebula contains a notable star named HD 89358, which is an unusual type of extremely hot and massive star known as a Wolf-Rayet star. HD 89358 generates incredibly intense stellar winds and outflows that smash into and sweep up the surrounding material, contributing to NGC 3199’s twisted and lopsided morphology.

The VST, which began operations in 2011, can image a large area of sky at once — an area twice the size of the full Moon — with its 256-megapixel camera, OmegaCAM. This allows it to characterise interesting objects which its larger neighbour, ESO’s Very Large Telescope, can then explore in even greater detail.

Credit: ESA/Hubble & NASA -- Acknowledgement: Judy Schmidt (geckzilla.com)

---

Obtained for a research programme on star formation in old and distant galaxies, this NASA/ESA Hubble Space Telescope image obtained with its Wide Field Camera 3 (WFC3) demonstrates the immense effects of gravity; more specifically, it shows the effects of gravitational lensing caused by an object called SDSS J1152+3313.

Gravitational lenses — such as this galaxy cluster SDSS J1152+3313 — possess immense masses that wrap their surroundings and bend the light from faraway objects into rings, arcs, streaks, blurs, and other odd shapes. This lens, however, is not only wrapping the appearance of a distant galaxy — it is also amplifying its light, making it appear much brighter than it would be without the lens. Combined with the high image quality obtainable with Hubble, this gives valuable clues into how stars formed in the early Universe.

Star formation is a key process in astronomy. Everything that emits light is somehow connected to stars, so understanding how stars form is key to understanding countless objects lying across the cosmos. Astronomers can probe these early star-forming regions to learn about the sizes, luminosities, formation rates, and generations of different types of stars.

bystander wrote: ↑Mon Jul 30, 2018 7:48 pm Stormy Seas in Carina
ESO Picture of the Week | VST | 2018 Jul 30

Credit: ESO/VST

---

This ESO Picture of the Week shows a crescent-shaped cocoon of gas and dust — a nebula known as NGC 3199, which lies 12 000 light-years away from Earth. It appears to plough through the star-studded sky like a ship through stormy seas. This imagery is very appropriate due to NGC 3199’s location in Carina — a southern constellation which is named after the keel of a ship!

NGC 3199 was discovered by British astronomer John Herschel in 1834 as he compiled his famous catalogue of interesting night sky objects. The nebula has been the subject of numerous observations since, including those by ESO’s 8.2-metre Very Large Telescope (VLT) (eso0310, eso1117), and 2.6-metre VLT Survey Telescope (VST). The latter made the observations that comprise this image. The nebula’s bright crescent feature is now known to be part of a much larger but fainter bubble of gas and dust.

The nebula contains a notable star named HD 89358, which is an unusual type of extremely hot and massive star known as a Wolf-Rayet star. HD 89358 generates incredibly intense stellar winds and outflows that smash into and sweep up the surrounding material, contributing to NGC 3199’s twisted and lopsided morphology.

The VST, which began operations in 2011, can image a large area of sky at once — an area twice the size of the full Moon — with its 256-megapixel camera, OmegaCAM. This allows it to characterise interesting objects which its larger neighbour, ESO’s Very Large Telescope, can then explore in even greater detail.