On Fri, 30 Jun 2017 19:51:09 +0100, WA0CKY
wrote:


NGC 5698 is an SBb spiral in Bootes one degree east of Seginus (Gamma)
Bootes. It has a rather strange ice cream cone shape with a faint drawn
out arm or plume on the eastern side.


Am I imagining things or is there really a very faint plumey thing
falling "down" the image from the left-hand side of that galaxy?
If it's real, I'm seeing it as several times the width of the starry
part in length.

It's probably an artifact of the processing.


Usually, such distortion is due
to an interaction with another nearby galaxy. NGC 5732 is the nearest
candidate with a similar redshift but is perfectly normal looking so
probably isn't the culprit. I checked a few others in the area but they
were either the wrong distance and/or undisturbed. It could be due to a
merger but I found no papers discussing anything to do with its
distorted shape or suggesting it has interacted with anything. So how
it ended up looking like it does is still a mystery to me. If anyone
knows more please let me know. Ignoring the plumes I get a size of
85,000 light-years. Including them I get 135,000 light-years for a size
assuming it is 180 million light-years from us as NED's redshift using
the 5 year WMAP data shows. It was discovered by William Herschel on
May 16, 1787 but didn't make either H400 observing program.

The other interesting object in my image is LEDA 097532 a pair of
obviously interacting galaxies with a plume appearing to connect the two
though it could be in front of or behind the other galaxy. Again, I
found nothing on their interaction. They are about 480 to 490 million
light-years distant. I get a size for the northern galaxy of 43,000
light years and a bit over 100,000 light-years for the southern galaxy
thanks to its plumes. The projected distance between their cores is
60,000 light-years. Projected distance assumes they are equally distant
from us. Since this is unlikely their true separation distance is
likely larger, how much larger is the question.

While transparency was finally excellent for this image allowing me to
easily go beyond 22nd magnitude and pick up galaxies NED shows at over 5
billion light-years, seeing would suddenly distort things severely.
This resulted in some stars being elongated in various directions and
other, often only a short angular distance away, looking normal. I
can't recall ever having such distortion before. Very odd.

14" LX200R @ f/10, L=4x10' RGB=2x10', STL-11000XM, Paramount ME


Thank you for all of these, many are incredibly lovely.

I need a Starship!
Mand.


Rick