Starship Asterisk*

Image Credit: ESA/Hubble & NASA ~ Acknowledgement: Judy Schmidt

---

This week’s NASA/ESA Hubble Space Telescope image showcases the galaxy NGC 4036: a lenticular galaxy some 70 million light-years away in the constellation of Ursa Major (the Great Bear).

This galaxy is known for its irregular lanes of dust, which form a swirling spiral pattern around the centre of the galaxy. This core is surrounded by an extended, hazy aura of gas and dust that stretches further out into space and causes the warm, fuzzy glow that can be seen here. The centre itself is also intriguing; it is something known as a LINER-type (Low-Ionisation Nuclear Emission-line Region) galactic nucleus, meaning that it displays particular emission lines within its spectrum. The particularly bright star visible slightly to the right of the galactic centre is not within the galaxy itself; it sits between us and NGC 4036, adding a burst of brightness to the scene.

Due to its relative brightness, this galaxy can be seen using an amateur telescope, making it a favourite amongst backyard astronomers and astrophotography aficionados.

Image Credit: Alberto Ghizzi Panizza / ESO

---

ESO’s La Silla Observatory, situated in northern Chile, offers the resident telescopes unrivalled views of both the cosmos and the region’s barren, but beautiful landscape. Photographed by Alberto Ghizzi Panizza from the ramp leading to ESO’s New Technology Telescope (NTT), this view captures La Silla under the magnificence of the Milky Way, which unmistakably carves its way across the night sky overhead.

Sitting proudly at the centre of the frame is the ESO 3.6-metre telescope, host of the planet-hunting HARPS instrument. Below sits the small grey and white enclosure (nicknamed the sarcofago, or sarcophagus) of the Télescope à Action Rapide pour les Objets Transitoires (TAROT). To the far right, the silver-sheened back of the decommissioned 15-metre Swedish-ESO Submillimetre Telescope (SEST) can be seen atop an isolated peak, and, finally, to the left of the road in the foreground sits the corrugated paneling and white dome of the Swiss 1.2-metre Leonhard Euler Telescope.

La Silla is located in the southern part of the Atacama Desert, 600 kilometres north of Santiago de Chile and at an altitude of 2400 metres. The site was ESO's first ever observing site, and has been in operation since the 1960s.

Credit: ESA/Hubble & NASA

---

Following on from last week’s Picture of the Week, this week we showcase the second part of the Hubble Deep UV (HDUV) Legacy Field, the GOODS-South view. With the addition of new ultraviolet light imagery, astronomers using the NASA/ESA Hubble Space Telescope have captured the largest panoramic view of the fire and fury of star birth in the distant Universe, encompassing 12 000 star-forming galaxies.

Hubble’s ultraviolet vision opens up a new window on the evolving Universe, tracking the birth of stars over the last 11 billion years up to the cosmos’s busiest star-forming period, which happened about three billion years after the Big Bang.

So far, ultraviolet light has been the missing piece of the cosmic puzzle. Now, combined with data in infrared, and visible light from Hubble and other space- and ground-based telescopes, astronomers have assembled the most comprehensive portrait yet of the Universe’s evolutionary history. The image straddles the gap between the very distant galaxies, which can only be viewed in infrared light, and closer galaxies, which can be seen across different wavelengths. The light from distant star-forming regions in remote galaxies started out as ultraviolet, but the expansion of the Universe has shifted the light into infrared wavelengths. By comparing images of star formation in the distant and nearby Universe, astronomers can get a better understanding of how nearby galaxies grew from small clumps of hot, young stars long ago.

The observation programme harnessed the ultraviolet vision of Hubble’s Wide Field Camera 3 (WFC3). This study extends and builds on the previous Hubble multi-wavelength data in the CANDELS-Deep (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey) fields within the central part of the GOODS (The Great Observatories Origins Deep Survey) fields. This mosaic is 14 times the area of the Hubble Ultraviolet Ultra Deep Field (UVUDF) released in 2014.

Ann wrote: ↑Sun Aug 26, 2018 6:18 pm

Guest wrote: ↑Sun Aug 26, 2018 6:07 pm Thanks. Unfortunately, have you keep file size under limit to post here . Yes shot in Suffolk UK

Contact Geckzilla. She just helped another person here post a large picture, when he was unable to do so himself.

Ann
Thanks Ann , yes i updated and posted larger files now so hopefully enough resolution -)

Credit: Petr Horálek/ESO

---

This Picture of the Week shows a huge celestial “V” emblazoned across the night sky over ESO’s Paranal Observatory, which is situated atop Cerro Paranal in Chile.

One arm of the “V” is noticeably clearer than the other; the right arm, pointing towards the top right corner of the frame, is traced out by the beautiful star-studded centre of the Milky Way. The fainter arm, leaning leftwards, is formed of glowing columns of diffuse zodiacal light, a phenomenon caused by incoming sunlight that is scattered by small particles of cosmic dust.

While we often see both the Milky Way and zodiacal light at Paranal thanks to the site’s famously clear skies, the “V” alignment shown here is unusual. Zodiacal light is related to the Earth’s path through space, as the dust particles responsible for scattering the sunlight are all within a cloud that lies on the ecliptic plane (dubbed the zodiacal cloud). Because of this, the glow varies in strength and visibility throughout the year, and is best seen in spring and autumn just after sunset or before sunrise. The opportunity to observe a beam of zodiacal light seeming to emanate from the very centre of the Milky Way comes only once per year, during January. For more information on this cosmic phenomenon, see ESOcast 82: Zodiacal light (esocast82a).

In the crook of the “V” sits one of ESO’s Very Large Telescope’s 1.8-metre Auxiliary Telescopes (ATs) — of which there are four in total. Each AT is housed in a robust enclosure that protects the delicate telescope and instrumentation from the harsh, arid desert conditions experienced at the site. Two other ATs are visible in the background towards the left side of the image.

The picture was taken by ESO Photo Ambassador Petr Horálek.

Guest wrote: ↑Sun Aug 26, 2018 6:07 pm Thanks. Unfortunately, have you keep file size under limit to post here . Yes shot in Suffolk UK

shaunnesy wrote: ↑Sun Aug 26, 2018 5:55 pm I have been shooting with my star adventurer and canon 6D a few nights ago at my local dark sky spot in Suffolk UK
Spent 2 nights as astronomical darkens returned to this latitude . The result is a stacked panoramic of 10 x 50 second images in each pane of which there are 8 .
Had to deal with a combine harvester going up and down fields opposite and time exposures to suite!
Used my Sigma 50mm Art lens and shot at ISO 2000 , f2.8
One image labelled

starsurfer wrote: ↑Sun Aug 26, 2018 4:45 pm
When on Earth is Adam Block going to release an image of a planetary nebula?! I've been waiting years!

Ann wrote: ↑Sun Aug 26, 2018 1:56 pm NGC 4691
http://www.caelumobservatory.com/gallery/n4691.shtml
Copyright: Adam Block

NGC 4691.png

Adam Block has posted a new picture of a galaxy, the remarkable barred spiral galaxy NGC 4691.

The entire spiral pattern of NGC 4691 is extremely fuzzy and devoid of any signs of youth. It looks like it is billions of years old. The bar, by contrast, is bursting with ongoing star formation. This is very unusual!

According to Principal Galaxy Catalog, the distance to NGC 4691 is about 47 million light-years, which would make it a little closer than the Virgo Cluster, and its true brightness would be 6 billion stars like the Sun, or 0.3 times the brightness of the Milky Way. But according to this page, NGC 4691 is located some 73 million light-years away, and its true brightness would be much higher.

Ann

Image Credit: ESA/Hubble & NASA

---

The Hubble Deep Field (HDF) from 1995 allowed astronomers a first glimpse into the early Universe. This first picture was followed later by an even deeper observation, the Hubble Ultra Deep Field (HUDF) in 2004. Both images were observed in visible light, the same form of light human eyes can see. But astronomers are also interested in the many forms of invisible light out in the Universe. Therefore, the Ultra Deep Field was later observed in the infrared and the ultraviolet as well, allowing scientists to learn even more about the Universe and to look back even further into its history.

It is less known that the famous deep field observations were not the only images the NASA/ESA Hubble Space Telescope took of the distant Universe. Hubble is also an essential part of the GOODS (The Great Observatories Origins Deep Survey) programme, which unites extremely deep observations from several space telescopes: NASA’s Spitzer and Chandra; ESA's Herschel and XMM-Newton; and Hubble.

Together these observatories observe two patches of the sky, the GOODS North and the GOODS South fields, with the aim of studying it in as many different wavelengths as possible. The new image here shows part of the GOODS North Field; it includes new Hubble data at ultraviolet wavelengths in addition to the existing data. Because Earth’s atmosphere filters out most ultraviolet light, these observations can only be accomplished from space.

The observation programme, called the Hubble Deep UV (HDUV) Legacy Survey, harnessed the ultraviolet vision of Hubble’s Wide Field Camera 3 (WFC3). This study extends and builds on the previous Hubble multi-wavelength data in the CANDELS-Deep (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey) fields within the central part of the GOODS (The Great Observatories Origins Deep Survey) fields. This mosaic is 14 times the area of the Hubble Ultraviolet Ultra Deep Field (UVUDF) released in 2014.

Image Credit: Petr Horálek/ESO

---

In this spectacular image, taken by ESO Photo Ambassador Petr Horálek, we see the bright arc of the Milky Way stretching across the sky above ESO’s La Silla Observatory in Chile. On the ground are the dome of ESO’s 3.6-metre optical telescope (on the right) and the silvery dish of the Swedish-ESO submillimetre telescope (on the left). Even though it was decommissioned in 2003 to make way for the more advanced APEX and ALMA instruments, the Swedish-ESO dish still seems to be gazing longingly at the sky, perhaps hoping for another chance to explore the mysteries of the heavens.

The Milky Way dominates this image, showing clearly why La Silla is one of the best astronomical sites in the world, famed for its dark skies and clear air. From the peak of the bright arc hangs a striking red feature known as Gum Nebula. This, like similar regions along the band of the Milky Way, is an emission nebula, where gas is made to glow by radiation emitted from nearby bright stars. The bright band of the Milky Way is broken up by dark filaments of dust, wherein stars are forming, stars that will add to the spectacle in the millennia to come.

Sitting under the arc is one of the Milky Way’s companion dwarf galaxies, the Large Magellanic Cloud; below it, just to the right of the Swedish-ESO dish, is the second such companion, known unsurprisingly as the Small Magellanic Cloud. Over to the right of the image is the planet Jupiter, glowing brightly against the faint glow of the gegenschein, a phenomenon only seen in the darkest skies. A rare sight for most, this magical celestial display is commonplace at astronomical observing sites like La Silla.

Credit: ESA/Hubble & NASA, RELICS

---

Galaxies abound in this spectacular Hubble image; spiral arms swirl in all colours and orientations, and fuzzy ellipticals can be seen speckled across the frame as softly glowing smudges on the sky. Each visible speck of a galaxy is home to countless stars. A few stars closer to home shine brightly in the foreground, while a massive galaxy cluster nestles at the very centre of the image; an immense collection of maybe thousands of galaxies, all held together by the relentless force of gravity.

Galaxy clusters are some of the most interesting objects in the cosmos. They are the nodes of the cosmic web that permeates the entire Universe — to study them is to study the organisation of matter on the grandest of scales. Not only are galaxy clusters ideal subjects for the study of dark matter and dark energy, but they also allow the study of farther-flung galaxies. Their immense gravitational influence means they distort the spacetime around them, causing them to act like giant zoom lenses. The light of background galaxies is warped and magnified as it passes through the galaxy cluster, allowing astronomers insight into the distant — and therefore early — Universe.

This image was taken by Hubble’s Advanced Camera for Surveys (ACS) and Wide-Field Camera 3 (WFC3) as part of an observing programme called RELICS (Reionization Lensing Cluster Survey). RELICS imaged 41 massive galaxy clusters with the aim of finding the brightest distant galaxies for the forthcoming NASA/ESA/CSA James Webb Space Telescope (JWST) to study.

Credit: Petr Horálek/ESO

---

This fulldome view of the Very Large Telescope (VLT), at ESO’s Paranal Observatory, shows almost all of the telescope’s constituent units in one family photograph!

ESO's VLT comprises four large 8.2-metre Unit Telescopes (UTs), all of which can be seen here and are recognised by their boxy appearance, and four 1.8-metre Auxiliary Telescopes (ATs), two of which are seen here flanking their bigger relatives (both with their rounded domes open). Alongside their standard designations — UT1, UT2, and so on — each of the four giant UTs has its own name in the local Chilean Mapuche language: Antu (The Sun), Kueyen (The Moon), Melipal (The Southern Cross), and Yepun (Venus).

The yellow laser streaking up into the night sky, launched by one of the UTs, creates an artificial star high in the atmosphere, fittingly known as a Laser Guide Star (LGS). This ‘star’ is part of the telescope’s adaptive optics system, which allows astronomers to compensate for the effects of atmospheric turbulence and achieve far clearer images.

The image was created by ESO Photo Ambassador Petr Horálek, and is a puzzle made up of numerous different pictures stitched together to form this high resolution panorama.