Starship Asterisk*

geckzilla wrote:That's a pretty weird PN.

Light and dark

Click to view full size image

http://www.spacetelescope.org/images/potw1434a/
This new NASA/ESA Hubble Space Telescope image shows a variety of intriguing cosmic phenomena.

Surrounded by bright stars, towards the upper middle of the frame we see a small young stellar object (YSO) known as SSTC2D J033038.2+303212. ... In this view from Hubble’s Advanced Camera for Surveys(ACS) it appears to have a murky chimney of material emanating outwards and downwards, framed by bright bursts of gas flowing from the star itself. ...

However, this small bright speck is dwarfed by its cosmic neighbour towards the bottom of the frame, a clump of bright, wispy gas swirling around as it appears to spew dark material out into space. The bright cloud is a reflection nebula known as [B77] 63, a cloud of interstellar gas that is reflecting light from the stars embedded within it. There are actually a number of bright stars within [B77] 63, most notably the emission-line star LkHA 326, and its very near neighbour LZK 18.

These stars are lighting up the surrounding gas and sculpting it into the wispy shape seen in this image. However, the most dramatic part of the image seems to be a dark stream of smoke piling outwards from [B77] 63 and its stars — a dark nebula called Dobashi 4173. ...

MargaritaMc wrote:

Light and dark

Click to view full size image

http://www.spacetelescope.org/images/potw1434a/
This new NASA/ESA Hubble Space Telescope image shows a variety of intriguing cosmic phenomena.

Surrounded by bright stars, towards the upper middle of the frame we see a small young stellar object (YSO) known as SSTC2D J033038.2+303212. ... In this view from Hubble’s Advanced Camera for Surveys(ACS) it appears to have a murky chimney of material emanating outwards and downwards, framed by bright bursts of gas flowing from the star itself. ...

However, this small bright speck is dwarfed by its cosmic neighbour towards the bottom of the frame, a clump of bright, wispy gas swirling around as it appears to spew dark material out into space. The bright cloud is a reflection nebula known as [B77] 63, a cloud of interstellar gas that is reflecting light from the stars embedded within it. There are actually a number of bright stars within [B77] 63, most notably the emission-line star LkHA 326, and its very near neighbour LZK 18.

These stars are lighting up the surrounding gas and sculpting it into the wispy shape seen in this image. However, the most dramatic part of the image seems to be a dark stream of smoke piling outwards from [B77] 63 and its stars — a dark nebula called Dobashi 4173. ...

I was really taken aesthetically by the chiaroscuro of this image. It's interesting astronomically as well.


Margarita

starsurfer wrote: Also the description mentions that the dark nebula is Dobashi 4173 but the Dobashi catalogue is of infrared dark clouds. I don't know what filters were used for the Hubble image and don't know whether it is visible.

http://www.ast.obs-mip.fr/article.php3?id_article=481

Atlas and Catalog of Dark Clouds Based on Digitized Sky Survey I

In this talk, I will introduce a quantitative atlas and catalog of dark clouds derived by using the optical database Digitized Sky Survey.

In space, there are many regions which are hidden from optical telescopes because they are embedded in dense regions of gas and dust. However, infrared radiation, having wavelengths which are much longer than visible light, can pass through dusty regions of space without being scattered. This means that we can study objects hidden by gas and dust in the infrared, which we cannot see in visible light, such as the center of our galaxy and regions of newly forming stars.
http://coolcosmos.ipac.caltech.edu/cosm ... tance.html

MargaritaMc wrote:

starsurfer wrote: Also the description mentions that the dark nebula is Dobashi 4173 but the Dobashi catalogue is of infrared dark clouds. I don't know what filters were used for the Hubble image and don't know whether it is visible.

I'd not heard of the Dobashi catalogue, but when I've just googled I found this record of a presentation by Kazuhito Dobashi

http://www.ast.obs-mip.fr/article.php3?id_article=481

Atlas and Catalog of Dark Clouds Based on Digitized Sky Survey I

In this talk, I will introduce a quantitative atlas and catalog of dark clouds derived by using the optical database Digitized Sky Survey.

My assumption would be that optical data would show that there is obscuring dust of some kind and infrared observations can peer through the dust to get an idea what's within.

In space, there are many regions which are hidden from optical telescopes because they are embedded in dense regions of gas and dust. However, infrared radiation, having wavelengths which are much longer than visible light, can pass through dusty regions of space without being scattered. This means that we can study objects hidden by gas and dust in the infrared, which we cannot see in visible light, such as the center of our galaxy and regions of newly forming stars.
http://coolcosmos.ipac.caltech.edu/cosm ... tance.html

Thanks for the info about the square brackets used in the Bernes' catalogue! I had wondered about asking if anyone knew.

Margarita

This new NASA/ESA Hubble Space Telescope image shows a beautiful spiral galaxy known as PGC 54493, located in the constellation of Serpens (The Serpent). This galaxy is part of a galaxy cluster that has been studied by astronomers exploring an intriguing phenomenon known as weak gravitational lensing.

This effect, caused by the uneven distribution of matter (including dark matter) throughout the Universe, has been explored via surveys such as the Hubble Medium Deep Survey. Dark matter is one of the great mysteries in cosmology. It behaves very differently from ordinary matter as it does not emit or absorb light or other forms of electromagnetic energy — hence the term "dark".

Even though we cannot observe dark matter directly, we know it exists. One prominent piece of evidence for the existence of this mysterious matter is known as the "galaxy rotation problem". Galaxies rotate at such speeds and in such a way that ordinary matter alone — the stuff we see — would not be able to hold them together. The amount of mass that is "missing" visibly is dark matter, which is thought to make up some 27% of the total contents of the Universe, with dark energy and normal matter making up the rest. PGC 55493 has been studied in connection with an effect known as cosmic shearing. This is a weak gravitational lensing effect that creates tiny distortions in images of distant galaxies.

The bright, hazy smudge at the centre of this image is a comet known as 67P/Churyumov-Gerasimenko, or 67P/C-G for short. This is not just any comet; it is the target for ESA’s Rosetta spacecraft, which is currently deep within the comet’s coma and less than 100 kilometres from its nucleus. With Rosetta so close to the comet, the only way to view the whole of 67P/C-G now is to observe it from the ground.

This image was taken on 11 August 2014 using one of the 8-metre telescopes of ESO’s Very Large Telescope (VLT) in Chile. It was composed by superimposing 40 individual exposures, each lasting 50 seconds, and removing background stars, to obtain the optimal view of the comet. Rosetta is contained within the central pixel of this image, and is too small to resolve. ...

Far beyond the stars in the constellation of Leo (The Lion) is irregular galaxy IC 559.

IC 559 is not your everyday galaxy. With its irregular shape and bright blue spattering of stars, it is a fascinating galactic anomaly. It may look like sparse cloud, but it is in fact full of gas and dust which is spawning new stars.

Discovered in 1893, IC 559 lacks the symmetrical spiral appearance of some of its galactic peers and not does not conform to a regular shape. It is actually classified as a “type Sm” galaxy — an irregular galaxy with some evidence for a spiral structure. ...

[url=http://www.eso.org/public/images/ann14065b/][b][i]ALMA short wavelength image of Uranus[/i][/b][/url] [b][i]Image Credit: ALMA (ESO/NAOJ/NRAO)[/i][/b]

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The Atacama Large Millimeter/submillimeter Array (ALMA) has reached a major milestone by extending its vision fully into the realm of the submillimetre, the wavelengths of cosmic light that hold intriguing information about the cold, dark, and distant Universe.

This achievement opens an entirely new window on the Universe for ALMA beyond its existing capabilities with the Band 9 receivers. It also is a critical step in the telescope's commissioning process, which brings its full capabilities to bear and makes them available to the international astronomical community.

As a demonstration of its new capabilities, the commissioning team released a new image of planet Uranus as it appears in submillimetre wavelength light. The image — obtained with ALMA's shortest wavelength, Band 10 receivers — reveals the icy glow from the planet's atmosphere, which can reach temperatures as low as -224 C (giving Uranus the coldest atmosphere in the Solar System). ALMA's now broader range of capabilities will enable astronomers and planetary scientists to study and monitor temperature changes at different altitudes above the clouds of Uranus and other giant planets in our Solar System. ...