Starship Asterisk*

Spiral Galaxy M96 from Hubble

Explanation: Dust lanes seem to swirl around the core of Messier 96 in this colorful, detailed portrait of the center of a beautiful island universe. Of course M96 is a spiral galaxy, and counting the faint arms extending beyond the brighter central region, it spans 100 thousand light-years or so, making it about the size of our own Milky Way. M96, also known as NGC 3368, is known to be about 35 million light-years distant and a dominant member of the Leo I galaxy group. The featured image was taken by the Hubble Space Telescope. The reason for M96's asymmetry is unclear -- it could have arisen from gravitational interactions with other Leo I group galaxies, but the lack of an intra-group diffuse glow seems to indicate few recent interactions. Galaxies far in the background can be found by examining the edges of the picture.

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To me, M96 is the galaxy that seems to carry a fascinating edge-on very red spiral galaxy on its outer arm on its left (east) side. Note that the elegant edge-on spiral has been perfectly bisected by a straight black dust lane.

I wondered why I couldn't see that slim red edge-on spiral in the APOD. Answer: The spiral tangled in the outer arm of M96 is off the edge of today's APOD.

To me, M96 appears to have a huge central bulge, which makes it slightly reminiscent of M81. But of course, M96 has that one weird dust lane which connects the core with the inner ring. Perhaps there is a dust lane on the other side as well, but it can't be seen in the APOD.

M81 is an unbarred galaxy, and therefore it lacks the funny dust lane that can be seen in M96.

Ann

As Ann's post picture shows...today's APOD is only the central region...not the whole of the galaxy...so you don't get a true perspective...this galaxy is still very much in a state of "disruption"...either mergers, or "group affected", I would think...

Do a search for M96 galaxy...many other images showing a huge "halo" and such...

Awesome image from Hubble...
:---[===] *

Kinda different; but still beautiful is M 96!

I’ve dabbled in astronomy since 1967, and I still can’t begin to wrap my mind around a distance like “35 million light years”. And images like this from that distance only boggle me further.

Jim Leff wrote: ↑Wed Jun 12, 2019 2:55 pm I’ve dabbled in astronomy since 1967, and I still can’t begin to wrap my mind around a distance like “35 million light years”. And images like this from that distance only boggle me further.

Hey... I can't wrap my mind around distances like 4 light-years. I can't really imagine the distance to Proxima Centauri. I can't picture it in my mind. In fact, I don't think I can imagine the distance to Pluto.

Ann

Jim Leff wrote: ↑Wed Jun 12, 2019 2:55 pm I’ve dabbled in astronomy since 1967, and I still can’t begin to wrap my mind around a distance like “35 million light years”. And images like this from that distance only boggle me further.

Well lets do an exercize in wrapping a head around. On Star Trek obviously we need warp speed to travel from star to star. Captain Kirk's Enterprise usually has Warp 10 as top speed, but they only do that when they are running qaway from a battleship. The usual speed is Warp Factor 4 Mr. Sulu. Now how fast is that. We know that Captain Kirk usually leaves 1 planet and exactly a week later he arrives at a different planet for more adventures. Now if we assume the closest stars are 4 light years apart, Captain Kirk travels 4 light years in 1 week. Still to travel to M 96 it would still take Kirk 168 thousand years. But the ship can travel faster. Kirk probably takes far less than the entire week. You can't see it on the Bridge, but there is a lounge on the Enterprise called 10 four or 10 forward that has windows to the outer space. When we see some guys talking when the ship is at warp you can see the stars fly by usually from the right and zooms past on the left. Now we see a point of light or a star zoom past and then maybe two or 3 seconds later another star zooms past. This means they are moving at about 4 light years every 2 or 3 seconds. Lets take 5 seconds to be on the conservative side. Roughly that's about 6 million light years in 1 year. Kirk would arrive at M96 in about 6 years. But then I wonder why it would take the Star Ship Voyager which is a much newer starship some 80 years to travel from the Delta Quadrant, the opposite end of the Milky Way, home, which really is only some 80,000 light years?

You can go as deep into Star Trek's warp factor as you want. Have a look at this fandom Wiki page. Scroll down to the second table and you'll see that warp factor 4 would get you to Alpha Centauri in about 25 days while warp 9 would get you there in 52 hours.

Rob

This a serenely beautiful image, with very pleasant coloring.

It also gives a great example of the technique that Ann suggested recently for guessing the closer part of an inclined spiral galaxy. Looking at the dust lanes, I feel they are strongly indicative that the part of this disk that is closest to earth is at about 4 or 5 o'clock in the image. Would others agree? With some Doppler data, we could investigate it as Art (neufer) suggested.

Ann wrote: ↑Wed Jun 12, 2019 4:53 am ... But of course, M96 has that one weird dust lane which connects the core with the inner ring. Perhaps there is a dust lane on the other side as well, but it can't be seen in the APOD.

M81 is an unbarred galaxy, and therefore it lacks the funny dust lane that can be seen in M96.

Ann

If you're talking about the dust lane I think you are, might this not just be perspective? My first guess -- I doubt it really is at all close to the galaxy core. I think it might just be well above the disk ... or is that possible? I would be suggesting thousands of light years above it.

I've used the narrow band F658N channel to highlight certain regions in red color (quite close to H-alpha emission line), which unfortunately was limited to about 2/3 of entire image field, but still adds additional detail and dimension to the final result. It's hard to find the missing data of this channel from other sources, but I'd like to keep looking for that. I've read that in many cases the H-alpha filter used by amateurs for deep sky imaging actually includes both Hydrogen and N-II spectral lines, which have completely different chemical element origins, but visually share very similar color.

As for the edge-on red spiral galaxy on its outer arm, it's very special and interesting object, but it was out of reach for current Hubble data set

Thank you all for nice comments!

Leo Shatz

MarkBour wrote: ↑Wed Jun 12, 2019 8:42 pm

Ann wrote: ↑Wed Jun 12, 2019 4:53 am ... But of course, M96 has that one weird dust lane which connects the core with the inner ring. Perhaps there is a dust lane on the other side as well, but it can't be seen in the APOD.

M81 is an unbarred galaxy, and therefore it lacks the funny dust lane that can be seen in M96.

Ann

If you're talking about the dust lane I think you are, might this not just be perspective? My first guess -- I doubt it really is at all close to the galaxy core. I think it might just be well above the disk ... or is that possible? I would be suggesting thousands of light years above it.

Good point, Mark. I think I should take back my claim that M96 is a barred galaxy. That weird dust lane warping one side of the bulge of the galaxy is not a normal "barred galaxy dust lane". All right, M96 does show signs of being barred because of the ring surrounding the inner bulge (such rings are typical of barred galaxies), but the dust lane is "wrong". M96 is warped, that's for sure. And for all I know, that dust lane could be located above the disk.

Ann

Everytime I see a galaxy I wonder about the early factors that cause it's formation.How exactly does a galaxy,like the one in today's apod, start forming and get to the point as we see it now? At it's earliest time does it form rather quickly?

Ann wrote: ↑Wed Jun 12, 2019 10:31 pm

MarkBour wrote: ↑Wed Jun 12, 2019 8:42 pm

Ann wrote: ↑Wed Jun 12, 2019 4:53 am
... But of course, M96 has that one weird dust lane which connects the core with the inner ring. Perhaps there is a dust lane on the other side as well, but it can't be seen in the APOD.

M81 is an unbarred galaxy, and therefore it lacks the funny dust lane that can be seen in M96.

If you're talking about the dust lane I think you are, might this not just be perspective? My first guess -- I doubt it really is at all close to the galaxy core. I think it might just be well above the disk ... or is that possible? I would be suggesting thousands of light years above it.

Good point, Mark. I think I should take back my claim that M96 is a barred galaxy. That weird dust lane warping one side of the bulge of the galaxy is not a normal "barred galaxy dust lane". I'm not sure that M96 is barred at all. It is warped, that's for sure. And for all I know, that dust lane could be located above the disk.

It woould seem that the star disk must be defined by resistant damping of the disk gas.

That goes double for disk dust.

A thick star disk or dust disk simply means that the gas disk is also thick.

In any event all 3 disks must lie in the same plane.

https://apod.nasa.gov/apod/ap170112.html
https://apod.nasa.gov/apod/ap190329.html

neufer wrote: ↑Thu Jun 13, 2019 1:59 am
In any event all 3 disks must lie in the same plane.

https://apod.nasa.gov/apod/ap170112.html
https://apod.nasa.gov/apod/ap190329.html

I refer you to your forum post back on the 2018-01-08 APOD of Andromeda ...

neufer wrote: ↑Mon Jan 08, 2018 4:05 pm

Ann wrote:
I have to wonder how common such thin ionized high-altitude cirrus clouds may be in and around spiral galaxies. Maybe they are quite common? Is it possible that Andromeda herself has such clouds, but we have yet to detect them?

• Isn't that exactly what that red spiral is "scattered hundreds of light-years" above Andromeda's arms

Am I confusing two different things here ?

Ann wrote: ↑Wed Jun 12, 2019 4:13 pm

Jim Leff wrote: ↑Wed Jun 12, 2019 2:55 pm I’ve dabbled in astronomy since 1967, and I still can’t begin to wrap my mind around a distance like “35 million light years”. And images like this from that distance only boggle me further.

Hey... I can't wrap my mind around distances like 4 light-years. I can't really imagine the distance to Proxima Centauri. I can't picture it in my mind. In fact, I don't think I can imagine the distance to Pluto.

Ann

That sounds perfectly proportional. I can’t begin to wrap my mind around a distance like
35 million light years, while you begin but fail to wrap your mind around distances like 4 light-years.