Starship Asterisk*

lizarranet wrote:Only a small patch of the huge Integrated Flux Nebula.

Authors: Deep Sky Team (Mikel Martínez, Cedric Thomas, Marian Gutowski, Franck Jobard)
Equipment: Takahashi FSQ106 plus Moravian G3-16200

The Milky Way arches over some of the 66 antennas that constitute the Atacama Large Millimeter/submillimeter Array (ALMA). This unique telescope peers into some of the coldest objects in our Galaxy and the beyond: molecules, interstellar dust and the building block of life itself.

Credit: D. Kordan/ESO

[img3="Credit: ESA/Hubble & NASA"]https://cdn.spacetelescope.org/archives ... w1748a.jpg[/img3][hr][/hr]

This picturesque view from the NASA/ESA Hubble Space Telescope peers into the distant Universe to reveal a galaxy cluster called Abell 2537.

Galaxy clusters such as this one contain thousands of galaxies of all ages, shapes and sizes, together totalling a mass thousands of times greater than that of the Milky Way. These groupings of galaxies are colossal — they are the largest structures in the Universe to be held together by their own gravity.

Clusters are useful in probing mysterious cosmic phenomena like dark matter and dark energy, the latter of which is thought to define the geometry of the entire Universe. There is so much matter stuffed into a cluster like Abell 2537 that its gravity has visible effects on its surroundings. Abell 2537’s gravity warps the very structure of its environment (spacetime), causing light to travel along distorted paths through space. This phenomenon can produce a magnifying effect, allowing us to see objects that lie behind the cluster and are thus otherwise unobservable from Earth. Abell 2537 is a particularly efficient lens, as demonstrated by the stretched stripes and streaking arcs visible in the frame. These smeared shapes are in fact galaxies, their light heavily distorted by the gravitational field of Abell 2537.

This spectacular scene was captured by Hubble’s Advanced Camera for Surveys and Wide-Field Camera 3 as part of an observing programme called RELICS.

[c][imghover=https://photojournal.jpl.nasa.gov/jpeg/PIA17218.jpg]https://s3.amazonaws.com/ciclops_ir_201 ... 0545_1.jpg[/imghover]Image Credit: NASA/JPL-Caltech/Space Science Institute[/c]

In a fitting farewell to the planet that had been its home for over 13 years, the Cassini spacecraft took one last, lingering look at Saturn and its splendid rings during the final leg of its journey and snapped a series of images that has been assembled into a new mosaic.

Cassini's wide-angle camera acquired 42 red, green and blue images, covering the planet and its main rings from one end to the other, on Sept. 13, 2017. Imaging scientists stitched these frames together to make a natural color view. The scene also includes the moons Prometheus, Pandora, Janus, Epimetheus, Mimas and Enceladus.

There is much to remember and celebrate in marking the end of the mission. Cassini's exploration of Saturn and its environs was deep, comprehensive and historic. ...

[img3="Credit: ESA/Hubble, NASA"]https://cdn.spacetelescope.org/archives ... w1747a.jpg[/img3][hr][/hr]

This NASA/ESA Hubble Space Telescope image reveals the Cosmic Snake, a distant galaxy peppered with clumpy regions of intense star formation that appear warped by the effect of gravitational lensing. This giant arc-like galaxy is actually behind the huge galaxy cluster MACS J1206.2-0847, but thanks to the cluster’s gravity, we can see it from Earth.

Light from the distant, high-redshift galaxy arrives at Earth, having been distorted by the gigantic gravitational influence of the intervening cluster. Fascinatingly, instead of making it more difficult to perceive cosmological objects, such strong lensing effects improve the resolution and depth of an image by magnifying the background object. Sometimes gravitational lensing can even produce multiple images of the object as light is bent in different directions around the foreground cluster.

Using Hubble, astronomers recently looked at several such images of the Cosmic Snake, each with a different level of magnification. Using this technique, the galaxy and its features could be studied on different scales. The highest-resolution images revealed that giant clumps in high-redshift galaxies are made up of a complex substructure of smaller clumps, which contributes to our understanding of star formation in distant galaxies.

• Nature Astronomy (online 13 Nov 2017) DOI: 10.1038/s41550-017-0295-x
  arXiv.org > astro-ph > arXiv:1711.03977 > 10 Nov 2017

[img3="Credit: ESO/Arrigoni Battaia et al"]https://cdn.eso.org/images/screen/potw1747a.jpg[/img3][hr][/hr]

This Picture of the Week shows a huge cloud of gas around the distant quasar SDSS J102009.99+104002.7, taken by the Multi Unit Spectroscopic Explorer (MUSE) instrument on ESO’s Very Large Telescope (VLT) at the Paranal Observatory. Quasars are the luminous centres of active galaxies, which are kept active by material falling onto the central supermassive black hole. This quasar and its surrounding cloud are at a redshift larger than 3, meaning that they are seen as they were only about 2 billion years after the Big Bang.

The cloud of gas (or nebula) surrounding the quasar is known to astronomers as an Enormous Lyman-Alpha Nebula (ELAN). These types of nebula are massive structures of gas which formed in the early Universe, and they can help astronomers to learn how angular momentum — which explains the observed rotation of more recent galaxies — was created in the Universe. Thanks to the revolutionary MUSE instrument, it is now possible to observe these rare giant nebulae in greater detail than ever before.

This particular ELAN has a diameter of about a million light-years, and MUSE’s spectral imaging capabilities have allowed astronomers to measure the signature of inspiraling motions within the nebula — for the first time ever.

Rolando Ligustri : Messier Album

Rolando Ligustri