Starship Asterisk*

Polar Ring Galaxy NGC 660

Explanation: NGC 660 is featured in this cosmic snapshot, a sharp composite of broad and narrow band filter image data from the Gemini North telescope on Mauna Kea. Over 20 million light-years away and swimming within the boundaries of the constellation Pisces, NGC 660's peculiar appearance marks it as a polar ring galaxy. A rare galaxy type, polar ring galaxies have a substantial population of stars, gas, and dust orbiting in rings nearly perpendicular to the plane of the galactic disk. The bizarre-looking configuration could have been caused by the chance capture of material from a passing galaxy by a disk galaxy, with the captured debris eventually strung out in a rotating ring. The violent gravitational interaction would account for the myriad pinkish star forming regions scattered along NGC 660's ring. The polar ring component can also be used to explore the shape of the galaxy's otherwise unseen dark matter halo by calculating the dark matter's gravitational influence on the rotation of the ring and disk. Broader than the disk, NGC 660's ring spans over 50,000 light-years.

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Amazing galaxy! Is there a Hubble image of comparable quality, or better, of this galaxy?

FLPhotoCatcher wrote:Amazing galaxy! Is there a Hubble image of comparable quality, or better, of this galaxy?

Hubble took some pictures of it but they don't show the whole thing in a single frame. Hmm, seems it hasn't been officially processed yet either so you have to look at the HLA. http://hla.stsci.edu/hlaview.html#Image ... 2CGHRS&ds=

Another "wow" moment!

We appear to live in a relatively straightforward barred spiral galaxy but still only have a rudimentary idea of it's actual size, shape and configuration - imagine living in NGC 660 and trying to sort it all out.

Here is another picture of NGC 660, which shows the galaxy in RGB. Here is a Hubble image of polar ring galaxy NGC 4650A. NGC 2685 is also regarded as a polar ring galaxy. Here is another picture of NGC 2685, which shows its polar ring structure better. Here is a Hubble picture of a pair of interacting galaxies, where one (NGC 3808A) definitely appears to be a polar ring galaxy. As for Mayall's Object, the polar ring appears to be displaced from the main galaxy.

Ann

In Polar Ring Galaxies, from Ann's examples, I notice the interesting thing is the ring seems to be the stripped off dust of the galaxy, while the inter part is mostly stars. Makes it all to appear to be one giant globular cluster...with a dust ring and star forming regions...hmmmm....a "Saturn" galaxy....Wondrous...

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Ann
Super interesting your links " here "
Very well

I'm so pleased that this image is on APOD! Before this image, I was unaware of all the HII regions in the ring, their presence is to be expected after a starburst event triggered by an interaction or whichever event created this weird galaxy! I'm wondering about its possible Wolf Rayet population and any associated WR nebulae. I can't wait for JWST and it's ability to resolve really small extragalactic nebulae.

FLPhotoCatcher wrote:Amazing galaxy! Is there a Hubble image of comparable quality, or better, of this galaxy?

There is Hubble data but there has never been an "official" image. However, amateur astrophotographer Rob Gendler processed the data and his version can be seen here: http://www.robgendlerastropics.com/NGC6 ... ndler.html

Thanks Ann and others for the links.
It appears that the image from the Gemini North telescope is the highest quality so far. Does anyone know if Hubble skips or delays imaging a galaxy if there is already a high quality image from another telescope?

FLPhotoCatcher wrote:Thanks Ann and others for the links.
It appears that the image from the Gemini North telescope is the highest quality so far. Does anyone know if Hubble skips or delays imaging a galaxy if there is already a high quality image from another telescope?

"Hubble" doesn't image anything. Researchers compete for observing time based on proposals relevant to their own interests. Certainly, if a researcher can make use of data from some other telescope, he's likely to do so. But in most cases, given the many possible filters available, such alternate data is likely to be complementary, not a substitute.

There are a number of NGC 660 HST images online, so clearly this object has been the object of study. In most cases, the nature of the observations does not produce data very suitable for creating "pretty pictures". However, both STSCI and interested amateurs mine the data to identify frames that can be processed and published for primarily aesthetic purposes.