Starship Asterisk*

bystander wrote: ↑Mon Jul 15, 2019 4:48 pm A Beautiful Whorl
ESA Hubble Picture of the Week | 2019 Jul 15

Image Credit: ESA/Hubble & NASA, L. Ho

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Galaxies come in many shapes and sizes. One of the key galaxy types we see in the Universe is the spiral galaxy, as demonstrated in an especially beautiful way by the subject of this Hubble Picture of the Week, NGC 2985. NGC 2985 lies roughly over 70 million light years from the Solar System in the constellation of Ursa Major (The Great Bear).

The intricate, near-perfect symmetry on display here reveals the incredible complexity of NGC 2985. Multiple tightly-wound spiral arms widen as they whorl outward from the galaxy’s bright core, slowly fading and dissipating until these majestic structures disappear into the emptiness of intergalactic space, bringing a beautiful end to their starry splendour.

Over aeons, spiral galaxies tend to run into other galaxies, often resulting in mergers. These coalescing events scramble the winding structures of the original galaxies, smoothing and rounding their shape. These objects possess a beauty all their own, distinct from the spiral galaxies from whence they came.

Susanna Kohler wrote:

This 53’-wide, false-color infrared image reveals the field containing the star cluster Trumpler 37, located ~3,000 light-years away. Here, T 37 can be seen near the head of IC 1396A, the colorful, bright-rimmed globule near the center of the image. In a recent study led by Huan Meng (Steward Observatory, University of Arizona), a team of scientists has used observations from the United Kingdom Infrared Telescope (UKIRT) spanning two full years to study the variability of stars in this young stellar cluster. The length of their study allowed them to identify 119 members of the cluster — discovering even low-mass members down to brown-dwarf size. By studying the stars in this cluster, Meng and collaborators hope to better understand what different factors drive young stellar objects like these to vary in emission — could it be changing accretion rates? Magnetic activity? Flares? Starspots? The effects of circumstellar disks? To find out what the authors learned, you can check out the article below.

• Astrophysical Journal 878(1):7 (2019 Jun 10) DOI: 10.3847/1538-4357/ab1b14
• arXiv.org > astro-ph > arXiv:1905.01246 > 03 May 2019

Susanna Kohler wrote:

The panels above show 10” x 14” images of dust emission from the disk that surrounds the young star PDS 70, captured with the Atacama Large Millimeter/submillimeter Array (ALMA). See that purple blob of emission on the inside-right of the disk in the center panel? According to a new study led by Andrea Isella (Rice University), that’s dust emission from what is likely a circumplanetary disk — a disk of gas and dust surrounding the newly forming giant planet PDS 70c, feeding its growth and possibly providing the material that will later form into one or more moons around the planet.

The PDS 70 system made headlines last year when its first planet, PDS 70b, was directly imaged (you can see it best in the background VLT/SPHERE image in the right panel).

In the grand scheme of a giant planet’s lifetime, the period of time when it is still surrounded by a circumplanetary disk is short, so PDS 70 system is one of the few instances where we’ve managed to capture this moment. By studying PDS 70, we hope to learn more about how gas giants — like our own Jupiter or Saturn — and their moon systems form. To learn more, check out the article below.

• Astrophysical Journal Letters 879(2):L25 () DOI: 10.3847/2041-8213/ab2a12
• arXiv.org > astro-ph > arXiv:1906.06308 > 14 Jun 2019

Image Credit: ESO/Yuri Beletsky (LCO)

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The modern building in this image is the Residencia at ESO's Paranal Observatory in Chile, a home from home for the many professionals and technicians working at the observatory. Above the astronomers’ home in the Atacama Desert, the image shows the Milky Way galaxy — our home in the Universe.

The Residencia was designed by the German architects Auer+Weber, and integrates perfectly into the arid landscape of the Atacama Desert in order to disturb astronomical observations as little as possible. The sandy colour and modern design of the building suit the Mars-like terrain around the observatory. The Residencia was chosen as the perfect hide-out for the Bond villain in the movie Quantum of Solace, and was blown up — only virtually — in one of the key scenes.

Paranal Observatory hosts ESO's Very Large Telescope (VLT), as well as four Auxiliary Telescopes (AT) that can work together to form the Very Large Telescope Interferometer (VLTI).

Image Credit: ESA/Hubble & NASA, L. Ho

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Every now and then, the NASA/ESA Hubble Space Telescope glimpses a common object — say, a spiral galaxy — in an interesting or unusual way. A sharply angled perspective, such as the one shown in this Picture of the Week, can make it seem as if we, the viewers, are craning our necks to see over a barrier into the galaxy's bright centre.

In the case of NGC 3169, this barrier is the thick dust embedded within the galaxy's spiral arms. Cosmic dust comprises a potpourri of particles, including water ice, hydrocarbons, silicates, and other solid material. It has many origins and sources, from the leftovers of star and planet formation to molecules modified over millions of years by interactions with starlight.

NGC 3169 is located about 70 million light-years away in the constellation of Sextans (The Sextant). It is part of the Leo I Group of galaxies, which, like the Local Group that houses our home galaxy, the Milky Way, is part of a larger galactic congregation known as the Virgo Supercluster.

starsurfer wrote: ↑Sat Jul 27, 2019 1:05 pm Jacoby 1
http://www.capella-observatory.com/Imag ... acoby1.htm
Copyright: Frank Sackenheim, Josef Pöpsel and Stefan Binnewies
Jacoby1.jpg

Ann wrote: ↑Sat Jul 27, 2019 7:45 pm

starsurfer wrote: ↑Sat Jul 27, 2019 1:05 pm Jacoby 1
http://www.capella-observatory.com/Imag ... acoby1.htm
Copyright: Frank Sackenheim, Josef Pöpsel and Stefan Binnewies
Jacoby1.jpg

That's a very interesting picture. The nebula is all blue, meaning it contains no hydrogen. The central star is very blue indeed, and it is quite obviously the bluest object in the picture. According to Simbad, the light output of this star peaks in the ultraviolet, and then it gets fainter and fainter at longer and longer wavelengths. It is really faint in infrared light.

This star seems to be at the threshold where it loses its planetary nebula "fluff" and becomes a white dwarf pure and simple.

Ann

Credit: ESO/SPECULOOS Team/E. Jehin

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This spectacular portrait of the Centaurus A galaxy was captured under clear skies by the newest operational ESO observatory, SPECULOOS (Search for habitable Planets EClipsing ULtra-cOOl Stars), located at the Paranal Observatory in Chile. The state of the art observatory is fitted an array of four one-metre telescopes, each named after one of the four Galilean moons. The SPECULOOS telescopes are neighbours of two of ESO’s most powerful telescopes, the Very Large Telescope (VLT) and VISTA. SPECULOOS is set to survey up to ten times more red dwarf stars than the TRAPPIST telescope (located at ESO La Silla Observatory) currently does. It is predicted statistically that it will then find at least twelve solar systems of a similar size to the now famous TRAPPIST-1 system.

The Centaurus A galaxy (NGC 5128) is one of the brightest objects in the southern hemisphere night sky, located in the constellation of Centaurus. It was discovered in 1826 by Scottish astronomer James Dunlop at the former Parramata Observatory. At a distance of 11 million light-years, it is the closest active galactic nucleus (AGN) to us. Astronomers theorise that what was originally an elliptical galaxy collided with a relatively smaller spiral shaped galaxy, giving it the peculiar shape we see now. NGC 5128 has an impressive collection of stars. From this image, you can observe red/pink star-forming regions on the bottom left of the image and young blue star clusters on the top right of the image; with dust lanes captured in stunning detail.

Towards the centre of the galaxy, leftover cosmic dust is slowly being eaten by the supermassive black hole, which has a mass of roughly 100 million solar masses. This accretion of matter results in powerful radio waves being emitted from the AGN.

This image was taken as one of the first light images from the SPECULOOS telescopes. First light images are the very first images that are taken by a telescope when it is being commissioned for science operation to guarantee that it is in good working order and that the images are clear.

Credit: ESA/Hubble & NASA, A. Filippenko, R. Jansen

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Believe it or not, this long, luminous streak, speckled with bright blisters and pockets of material, is a spiral galaxy like our Milky Way. But how could that be?

It turns out that we see this galaxy, named NGC 3432, orientated directly edge-on to us from our vantage point here on Earth. The galaxy’s spiral arms and bright core are hidden, and we instead see the thin strip of its very outer reaches. Dark bands of cosmic dust, patches of varying brightness, and pink regions of star formation help with making out the true shape of NGC 3432 — but it’s still somewhat of a challenge! Because observatories such as the NASA/ESA Hubble Space Telescope have seen spiral galaxies at every kind of orientation, astronomers can tell when we happen to have caught one from the side.

The galaxy is located in the constellation of Leo Minor (The Lesser Lion). Other telescopes that have had NGC 3432 in their sights include those of the Sloan Digital Sky Survey (SDSS), the Galaxy Evolution Explorer (GALEX), and the Infrared Astronomical Satellite (IRAS).