Starship Asterisk*

neufer wrote: ↑Tue Mar 26, 2019 4:11 pm

bystander wrote: ↑Tue Mar 26, 2019 3:45 pm
Interacting Galaxies Arp 194
Hubble Heritage (STScI/AURA) | 2019 Apr 21 [sic]

Arp 194, located in the constellation Cepheus, resides approximately 600 million light years away from Earth. Arp 194 is one of thousands of interacting and merging galaxies known in our nearby Universe. These observations were taken in January of 2009 with the Wide Field Planetary Camera 2. Blue, green and red filters were composited together to form the rather picturesque image of a galaxy interaction.

http://asterisk.apod.com/viewtopic.php? ... 25#p290857

bystander wrote: ↑Tue Mar 26, 2019 3:45 pm
Interacting Galaxies Arp 194
Hubble Heritage (STScI/AURA) | 2019 Apr 21 [sic]

Arp 194, located in the constellation Cepheus, resides approximately 600 million light years away from Earth. Arp 194 is one of thousands of interacting and merging galaxies known in our nearby Universe. These observations were taken in January of 2009 with the Wide Field Planetary Camera 2. Blue, green and red filters were composited together to form the rather picturesque image of a galaxy interaction.

neufer wrote: ↑Mon Mar 25, 2019 7:52 pm

SciTechDaily wrote:
Hubble Image of Arp 194 – Cosmic Optical Illusions in Ursa Major
By NASA, ESA and the Hubble Heritage Team (STScI/AURA)
September 21, 2015

This is actually a copy of an article at ESA Space Images. The image there is from Hubble Heritage and HubbleSite in April of 2009. There was also a write-up at the ESA Hubble site.

Interacting Galaxies Arp 194
Hubble Heritage (STScI/AURA) | 2009 Apr 21

Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

---

Over the past 19 years Hubble has taken dozens of exotic pictures of galaxies going “bump in the night” as they collide with each other and have a variety of close encounters of the galactic kind. Just when you thought these interactions couldn’t look any stranger, this image of a trio of galaxies, called Arp 194, looks like one of the galaxies has sprung a leak. The bright blue streamer is really a stretched spiral arm full of newborn blue stars. This typically happens when two galaxies interact and gravitationally tug at each other.

Resembling a pair of owl eyes, the two nuclei of the colliding galaxies can be seen in the process of merging at the upper left. The bizarre blue bridge of material extending out from the northern component looks like it connects to a third galaxy but in reality the galaxy is in the background and not connected at all. Hubble’s sharp view allows astronomers to try and visually sort out what are foreground and background objects when galaxies, superficially, appear to overlap.

The blue "fountain" is the most striking feature of this galaxy troupe and it contains complexes of super star clusters, that may have as many as dozens of individual young star clusters in them. It formed as a result of the interactions among the galaxies in the northern component of Arp 194. The gravitational forces involved in a galaxy interaction can enhance the star formation rate and give rise to brilliant bursts of star formation in merging systems.

Hubble's resolution shows clearly that the stream of material lies in front of the southern component of Arp 194, as evidenced by the dust that is silhouetted around the star cluster complexes.

The details of the interactions among the multiple galaxies that make up Arp 194 are complex. The system was most likely disrupted by a previous collision or close encounter. The shapes of all galaxies involved have been distorted by their gravitational interactions with one another.

Arp 194, located in the constellation Cepheus, resides approximately 600 million light years away from Earth. Arp 194 is one of thousands of interacting and merging galaxies known in our nearby Universe. These observations were taken in January of 2009 with the Wide Field Planetary Camera 2. Blue, green and red filters were composited together to form the rather picturesque image of a galaxy interaction.

Chris Peterson wrote: ↑Mon Mar 25, 2019 10:05 pm

Fred the Cat wrote: ↑Mon Mar 25, 2019 9:38 pm I was reading an article and noticed a reference to a 1982 article in Sci-Am “Charge-coupled Devices in Astronomy”. So, I ran downstairs and found the old journal. (They don't make even the old stuff available for us web surfers) It stated,” A single pictures made by a CCD imager 500 pixels on a side holds the same amount of raw information as a 100,000 word book..” I have no idea how today’s CCD’s might stack up.

It seems hard to imagine it’s been almost 40 years since CCD’s have been around to make images available like we see today.

I made this CCD image in 1977, a year out of high school. The sensor was a 100x100 element array made by Fairchild. Had to build the camera myself, and cool it with ice and alcohol. It's a 10 minute exposure with an autoguided 6-inch Newtonian (had to make the autoguider, too). Can't believe it was that long ago!

(Not much available in terms of display devices, either. I output this as a slow scan frame on an oscilloscope, a few seconds top to bottom, captured on a Polaroid camera. Scanned off the print years later. The digital data, if it still exists, must be floating around in a stored box of 8-inch floppy disks somewhere. I might have even output it to paper tape. 100x100x8-bit is only 10 kB, between 1% and 10% of a typical book in simple ASCII.)
_
ccd101.jpg

Fred the Cat wrote: ↑Mon Mar 25, 2019 9:38 pm I was reading an article and noticed a reference to a 1982 article in Sci-Am “Charge-coupled Devices in Astronomy”. So, I ran downstairs and found the old journal. :clap: (They don't make even the old stuff available for us web surfers) :( It stated,” A single pictures made by a CCD imager 500 pixels on a side holds the same amount of raw information as a 100,000 word book..” I have no idea how today’s CCD’s might stack up. :roll:

It seems hard to imagine it’s been almost 40 years since CCD’s have been around to make images available like we see today.

Nitpicker wrote: ↑Mon Mar 25, 2019 5:37 am
Another curious puzzle ... I've just noticed a number of different websites that say that Arp 194 is in Cepheus, when it is nowhere near Cepheus. It is in Ursa Major. I wonder who was the initial culprit to so successfully propagate this misinformation?

http://sci.esa.int/hubble/44682-constellation-region-near-arp-194/ wrote:
This picture, taken with a small ground-based camera, highlights the part of the northern sky that includes: Ursa Major, Coma Berenices, Canes Venatici and Cepheus [sic]. Arp 194 lies within the constellation of Cepheus [sic], just below and to the left of the "foot" of the Great Bear (Ursa Major).

https://en.wikipedia.org/wiki/UGC_6945 wrote:
UGC 6945 (also known as Arp 194)

Right ascension 11h 57m 54.87s
Declination +36° 23′ 32.8″

https://scitechdaily.com/hubble-image-of-arp-194-cosmic-optical-illusions-in-ursa-major/ wrote:

Released in 2009 to commemorate the Hubble’s 19th year in space, this image of Arp 194 shows several galaxies, along with a “cosmic fountain” of stars, gas, and dust that stretches over 100,000 light-years.

---

Hubble Image of Arp 194 – Cosmic Optical Illusions in Ursa Major
By NASA, ESA and the Hubble Heritage Team (STScI/AURA)
September 21, 2015

<<The galaxies at the top and bottom of the frame are named PGC 37639 and PGC 101374 respectively. Although it may look as if the two are in the middle of a galactic tug-of-war, connected by the prominent stream of blue through the center of the image, PGC 37639 lies somewhat closer to Earth than its companion, and the two are not physically connected.

In another optical trick, this image does not contain two galaxies, but at least four. The upper left patch actually hosts two galaxies in the early stages of merging. Their bright centers can still be seen separately, glowing amid a maelstrom of gas and dust. A smaller and relatively intact spiral galaxy, known as SDSSCGB 19.4, can be seen to the right of the merging duo. This trio of galaxies comprises Arp 194, a galaxy group just under 600 million light-years away from Earth in the constellation of Cepheus.

The blue stream is thought to have formed through the turbulent gravitational interactions occurring at the top of the frame — the uppermost galaxy clump is a whirl of flailing once-spiral arms. The stream is some 100,000 light-years long, and made up of gas, dust and many millions of newborn stars. These stars, which are clumped together to form star clusters, which in turn later accumulate as superclusters, are responsible for the striking blue hue visible here. They are mostly young, hot and massive, a combination that causes them to emit blue light.>>

zendae1 wrote: ↑Mon Mar 25, 2019 4:21 pm Is there no way to perhaps see this amalgamation from 'the side'? We have had simulations that offer supposed views before. I do wonder what this looks like from any perpendicular location! From the real view, it looks like a train wreck.

Chris Peterson wrote: ↑Mon Mar 25, 2019 2:35 pm

De58te wrote: ↑Mon Mar 25, 2019 8:41 am Uhm I might bring a controversy but doing a google search I found several sites including Wiki that say that the trio of colliding galaxies are in the top section. The two on the west side that are in direct collision and the smaller spiral galaxy on the east that is relatively unaffected. The arm of new star formation to the south is now thought to just be superimposed over the southern galaxy which isn't connected but just happens to be in the line of sight.

There are two galaxies colliding in the northern component. The third galaxy visible in the north may or may not be involved (it looks like a background object to me). The galaxy that forms the southern component may or may not be interacting significantly with the pair (or trio) of galaxies to the north, or with their tidally ejected material.

De58te wrote: ↑Mon Mar 25, 2019 8:41 am Uhm I might bring a controversy but doing a google search I found several sites including Wiki that say that the trio of colliding galaxies are in the top section. The two on the west side that are in direct collision and the smaller spiral galaxy on the east that is relatively unaffected. The arm of new star formation to the south is now thought to just be superimposed over the southern galaxy which isn't connected but just happens to be in the line of sight.

neufer wrote: ↑Mon Mar 25, 2019 1:56 pm

Ann wrote: ↑Mon Mar 25, 2019 1:19 pm
Just because Youtube says so, doesn't make it so.

The video is from 2010: https://www.youtube.com/watch?v=EDP5V4FOIzI

NASA says it's so; common sense says it so; etc.; etc., ...

(Besides...the center of galaxies don't just suck up neighboring galactic arms like a vacuum cleaner.)

If there's a recent (or any) scientific paper that argues otherwise please reference that paper.

https://arxiv.org/pdf/astro-ph/0212547.pdf wrote:

We have analyzed in detail the photometric properties and the kinematics of the strongly
interacting system Arp 194. The main constituents of this system are a collisional ring system
(A194N) and an intruder (A194S) that have experienced an interpenetrating, head-on encounter a
few 10⁸ yr ago. We have shown that tidally stripped gas is falling toward the center of the intruder,
A194S, and that it is fueling a strong nuclear and circumnuclear Starburst. Arp 194 is therefore
one of the few known objects for which convincing evidence of cross-fueling exists. Considering
that gas is usually confined in a “dynamically cold” configuration in disk galaxies, the Arp 194
case indicates transfer of orbital energy to the internal motion of gas during the the encounter. We
suggest that gas motions in superwind galaxies – which are mostly interacting systems – could also
be affected by the same mechanism.
Several aspects of the Arp 194 system deserve further scrutiny. The morphology of A194N
is fairly complex, and the distorted morphology of the ring as well as the bright arc of A194N
indicate the possibility of perturbations by a third party

Ann wrote: ↑Mon Mar 25, 2019 1:19 pm
Just because Youtube says so, doesn't make it so.

The video is from 2010: https://www.youtube.com/watch?v=EDP5V4FOIzI

neufer wrote: ↑Mon Mar 25, 2019 11:57 am

Click to play embedded YouTube video.

Ann wrote: ↑Mon Mar 25, 2019 9:19 am

De58te wrote: ↑Mon Mar 25, 2019 8:41 am
Uhm I might bring a controversy but doing a google search I found several sites including Wiki that say that the trio of colliding galaxies are in the top section. The two on the west side that are in direct collision and the smaller spiral galaxy on the east that is relatively unaffected. The arm of new star formation to the south is now thought to just be superimposed over the southern galaxy which isn't connected but just happens to be in the line of sight.

I read that too, but frankly, I doubt it. To me it is too much of a coincidence that a fantastic bridge emanating from a pair of interacting galaxies would just by chance happen to point at another extremely nearby galaxy, which, however, is not at all involved in the interaction.

neufer wrote: ↑Mon Mar 25, 2019 1:03 pm

orin stepanek wrote: ↑Mon Mar 25, 2019 12:37 pm
Is the little galaxy to the right of the three part of the merge?

It looks like it may be more distant from Earth; and I'm not seeing any disruption in it's arms! :?

The probability of two galaxies interacting (i.e., in close proximity in ALL 3 dimensions) at any one time is quite low.

The probability of three (or more) galaxies interacting is close to nil.

RocketRon wrote: ↑Mon Mar 25, 2019 5:13 am Would gravity be enough to reverse both these in their tracks, so to speak.
Thats a colossal amount of momentum they each have,,,,

orin stepanek wrote: ↑Mon Mar 25, 2019 12:37 pm
Is the little galaxy to the right of the three part of the merge?

It looks like it may be more distant from Earth; and I'm not seeing any disruption in it's arms!

Ann wrote: ↑Mon Mar 25, 2019 9:19 am

De58te wrote: ↑Mon Mar 25, 2019 8:41 am
Uhm I might bring a controversy but doing a google search I found several sites including Wiki that say that the trio of colliding galaxies are in the top section. The two on the west side that are in direct collision and the smaller spiral galaxy on the east that is relatively unaffected. The arm of new star formation to the south is now thought to just be superimposed over the southern galaxy which isn't connected but just happens to be in the line of sight.

I read that too, but frankly, I doubt it. To me it is too much of a coincidence that a fantastic bridge emanating from a pair of interacting galaxies would just by chance happen to point at another extremely nearby galaxy, which, however, is not at all involved in the interaction.

De58te wrote: ↑Mon Mar 25, 2019 8:41 am Uhm I might bring a controversy but doing a google search I found several sites including Wiki that say that the trio of colliding galaxies are in the top section. The two on the west side that are in direct collision and the smaller spiral galaxy on the east that is relatively unaffected. The arm of new star formation to the south is now thought to just be superimposed over the southern galaxy which isn't connected but just happens to be in the line of sight.

APOD Robot warote:

Analyses of images and data including the featured image of Arp 194 from Hubble, as well as computer simulations of the interaction, indicate that the bottom galaxy passed right through the top galaxy within the past 100 million years.