Starship Asterisk*

NHcycler wrote:
I'm surprised that NGC 1317 isn't deformed after the collision with 1316.

In fact, it's unusually symmetrical...

NHcycler wrote:I'm surprised that NG1317 isn't deformed after the collision with 1316. In fact, it's unusually symmetrical...

Sci News wrote:
The astronomers found that almost all of the galaxies with large amounts of radio emission, implying the presence of jets, were associated with galactic mergers.

https://en.wikipedia.org/wiki/NGC_1316 wrote:

[b][color=#0000FF]It has been proposed too that NGC 1316 may be a galaxy in evolution that eventually will become a Sombrero-like system dominated by a large bulge.[/color][/b]

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<<NGC 1316 (also known as Fornax A) is a lenticular galaxy about 60 million light-years away in the constellation Fornax. NGC 1316 is a radio galaxy. It is the fourth-brightest radio source in the sky (as seen at L band: 1400 MHz).

François Schweizer studied NGC 1316 extensively in the late 1970s. He found that the galaxy appeared to look like a small elliptical galaxy with some unusual dust lanes embedded within a much larger envelope of stars. The outer envelope contained many ripples, loops, and arcs. He also identified the presence of a compact disk of gas near the center that appeared inclined relative to the stars and that appeared to rotate faster than the stars. Based on these results, Schweizer suggested that NGC 1316 was built up through the merger of several smaller galaxies. These merger events may have fueled the central supermassive black hole, that has a mass estimated in 130-150 million of solar masses with gas, causing the galaxy to become a radio galaxy. He also states that NGC 1316 is comparable to the giant elliptical galaxies found in the centers of other clusters of galaxies. Using spectroscopy of its brightest globular clusters, the merger is estimated to have occurred ~3 billion years ago.

NGC 1316 is located within the Fornax Cluster, a cluster of galaxies in the constellation Fornax. However, in contrast to Messier 87, which is a similar elliptical galaxy that is located in the center of the Virgo Cluster, NGC 1316 is located at the edge of the Fornax Cluster. NGC 1316 appears to be interacting with NGC 1317, a small spiral galaxy to the north. However, that small spiral galaxy does not appear to be sufficiently large enough to cause the distortions seen in the structure of this galaxy. NGC 1316 was host to two Type Ia supernovae: 1980N(Ia) and 1981D(Ia).

At least two methods have been used to estimate the distance to NGC 1316: surface brightness fluctuation (SBF) in 2003 and planetary nebula luminosity function (PNLF) in 2006. Being a lenticular galaxy, it is not suitable to apply the cepheid variable method. Using SBF, a distance estimate of 20.0 ± 1.6 Mpc was computed. Using PNLF, 45 planetary nebula candidates were located and a distance estimate of 17.85 ±0.85 Mpc was computed. Averaged together, these two distance measurements give a combined distance estimate of 62.0 ± 2.9 Mly (19.0 ± 0.9 Mpc).>>

https://en.wikipedia.org/wiki/L_band wrote:
<<The L band, as defined by the IEEE, is the 1 to 2 GHz range of the radio spectrum. The L band contains the hyperfine transition of neutral hydrogen (the 21 centimeter hydrogen line, 1420 MHz), which is of great astronomical interest as a means of imaging the normally invisible neutral atomic hydrogen in interstellar space. Consequently, parts of the L-band are protected radio astronomy allocations worldwide.

In the United States and overseas territories, the L band is held by the military for telemetry, thereby forcing digital radio to in-band on-channel (IBOC) solutions. Digital Audio Broadcasting (DAB) is typically done in the 1452–1492 MHz range in most of the world, but some countries also use VHF and UHF bands. WorldSpace satellite radio broadcasts in the 1467–1492 MHz L sub-band.>>

De58te wrote:
Yes, isn't it strange that the smaller galaxy that is colliding isn't deformed at all. I am not an expert but what if they aren't actually colliding? Imagine that NGC 1317 is actually nearly the same size as NGC 1316, but it is twice as far away. It just happens to be in our line of sight by coincidence. Say for example if an observer in NGC 1316 were looking at the Milky Way, and Andromeda would be in the line of sight, that observer would conclude the Milky Way and Andromeda were colliding.

• One can only speculate that someone misread the HUBBLE SPIES COSMIC DUST BUNNIES caption.

APOD Explanation: Investigating the startling sight, astronomers suspect the giant galaxy of colliding with smaller neighbor NGC 1317 seen just above, causing far flung loops and shells of stars.

Julian wrote:APOD 2017 Feb 02 has got wrong links for "Previous APOD" and "Next APOD"

MH999 wrote:

Julian wrote:
APOD 2017 Feb 02 has got wrong links for "Previous APOD" and "Next APOD"

Today's APOD shows a date of Feb. 2 above the caption... We're stuck on Groundhog Day!