APOD: The M81 Galaxy Group through the... (2017 Jun 27)

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 2873
Joined: Fri Dec 04, 2009 3:27 am

APOD: The M81 Galaxy Group through the... (2017 Jun 27)

Postby APOD Robot » Tue Jun 27, 2017 4:06 am

Image The M81 Galaxy Group through the Integrated Flux Nebula

Explanation: Distant galaxies and nearby nebulas highlight this deep image of the M81 Group of galaxies. First and foremost in this 80-exposure mosaic is the grand design spiral galaxy M81, the largest galaxy in the image, visible on the lower right. M81 is gravitationally interacting with M82 just above it, a large galaxy with an unusual halo of filamentary red-glowing gas. Around the image many other galaxies from the M81 Group of galaxies can be seen, as well as many foreground Milky Way stars. This whole galaxy menagerie is seen through the glow of an Integrated Flux Nebula (IFN), a vast and complex screen of diffuse gas and dust also in our Milky Way Galaxy. Details of the red and yellow IFN, digitally enhanced, were imaged by a new wide-field camera recently installed at the Teide Observatory in the Canary Islands of Spain.

<< Previous APOD This Day in APOD Next APOD >>

Boomer12k
:---[===] *
Posts: 1964
Joined: Sun Apr 22, 2007 12:07 am

Re: APOD: The M81 Galaxy Group through the... (2017 Jun 27)

Postby Boomer12k » Tue Jun 27, 2017 5:41 am

It would be awesome to have a building, a dome, with the whole northern and southern sky like that, so you could see the continuous detail...

:---[===] *

NCTom

Re: APOD: The M81 Galaxy Group through the... (2017 Jun 27)

Postby NCTom » Tue Jun 27, 2017 10:22 am

In the enlarged photo there is a "bull's eye"galaxy in the upper right. Fascinating group of celestial citizens both intra- and intergalactic. Great photo!

User avatar
Cousin Ricky
Science Officer
Posts: 193
Joined: Mon Aug 26, 2013 4:08 pm
Location: St. Thomas, U.S. Virgin Islands (+18.3, -64.9)

Re: APOD: The M81 Galaxy Group through the... (2017 Jun 27)

Postby Cousin Ricky » Tue Jun 27, 2017 11:53 am

This image appears to be mirror reversed.

User avatar
neufer
Vacationer at Tralfamadore
Posts: 13983
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: The M81 Galaxy Group through the... (2017 Jun 27)

Postby neufer » Tue Jun 27, 2017 1:05 pm

Cousin Ricky wrote:
This image appears to be mirror reversed.

    ABLE WAS I (ERE) I SAW ELBA
https://en.wikiversity.org/wiki/Interstellar_medium wrote:
"[T]he extended red emission (ERE) [is] observed in many dusty astronomical environments, in particular, the diffuse interstellar medium of the Galaxy. ... silicon nanoparticles provide the best match to the spectrum and the efficiency requirement of the ERE."

"The broad, 60 < FWHM < 100 nm, featureless luminescence band known as extended red emission (ERE) is seen in such diverse dusty astrophysical environments as reflection nebulae, planetary nebulae, HII regions (Orion), a Nova, Galactic cirrus, a dark nebula, Galaxies and the diffuse interstellar medium (ISM). The band is confined between 540-950 nm, but the wavelength of peak emission varies from environment to environment, even within a given object. ... the wavelength of peak emission is longer and the efficiency of the luminescence is lower, the harder and denser the illuminating radiation field is13. These general characteristics of ERE constrain the photoluminescence (PL) band and efficiency for laboratory analysis of dust analog materials."Panspermia hypothesis
https://en.wikipedia.org/wiki/Red_Rectangle_Nebula wrote:
<<The Red Rectangle Nebula (HD 44179), so called because of its red color and unique rectangular shape, is a protoplanetary nebula in the Monoceros constellation. The Red Rectangle is known to be particularly rich in polycyclic aromatic hydrocarbons (PAHs). The presence of such carbon-bearing macromolecules in the X-shaped nebular component, while the equatorial regions are known to contain silicate-rich (O-bearing) dust grains, was interpreted as due to a change of the O/C abundance ratio of the primary star during its late evolution. However, PAHs could also be formed as a result of the development of a central photondissociation region, a region in which a very active chemistry appears due to dissociation of stable molecules by the UV emission of the central stellar system. The Red Rectangle was the first nebula around an evolved star in which an equatorial disk in rotation was well identified (the existence of such disks has been demonstrated only in a few of these objects, only expansion is observed in most of them).[8] However, the disk absorbs the stellar light and is practically not seen in the beautiful optical image, which mainly represents a relatively diffuse outflow that is very probably formed of material extracted from the denser disk. The distinct rungs suggest several episodes of increased ejection rate.>>
https://en.wikipedia.org/wiki/Red_rain_in_Kerala wrote:
<<The Kerala red rain phenomenon was a blood rain event that occurred from 25 July to 23 September 2001, when heavy downpours of red-coloured rain fell sporadically on the southern Indian state of Kerala, staining clothes pink. Coloured rain was also reported in Kerala in 1896 and several times since.

In 2003 Godfrey Louis and Santhosh Kumar, physicists at the Mahatma Gandhi University in Kottayam, Kerala, posted an article entitled "Cometary panspermia explains the red rain of Kerala" in the non-peer reviewed arXiv web site. While the CESS report said there was no apparent relationship between the loud sound (possibly a sonic boom) and flash of light which preceded the red rain, to Louis and Kumar it was a key piece of evidence. They proposed that a meteor (from a comet containing the red particles) caused the sound and flash and when it disintegrated over Kerala it released the red particles which slowly fell to the ground.

Their work indicated that the particles were of biological origin; using ethidium bromide they were unable to detect DNA or RNA in the particles. The team also observed the cells using phase contrast fluorescence microscopy, and they concluded that: "The fluorescence behaviour of the red cells is shown to be in remarkable correspondence with the extended red emission (ERE) observed in the Red Rectangle Nebula and other galactic and extragalactic dust clouds, suggesting, though not proving an extraterrestrial origin."

The abstract for their paper states that: The red cells found in the red rain in Kerala, India are now considered as a possible case of extraterrestrial life form. These cells can undergo rapid replication even at an extreme high temperature of 300 °C. They can also be cultured in diverse unconventional chemical substrates. The molecular composition of these cells is yet to be identified.>>
Art Neuendorffer

User avatar
Fred the Cat
Theoretic Apothekitty
Posts: 346
Joined: Mon Feb 22, 2016 4:09 pm
AKA: Ron

Re: APOD: The M81 Galaxy Group through the... (2017 Jun 27)

Postby Fred the Cat » Tue Jun 27, 2017 2:26 pm

Permit me the capacity to compare the concept of magnetic and electrical flux to IFN. No, I mean integrating flux from zero to infinity. Just kidding but it does make you curious how the name was derived. :facepalm:

Not to be confused with Infinite Flux. :wink:
Feynman's Felicity "Only ascertain as a cat box survivor"

User avatar
neufer
Vacationer at Tralfamadore
Posts: 13983
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

What the Flux?

Postby neufer » Tue Jun 27, 2017 3:07 pm

Fred the Cat wrote:
Permit me the capacity to compare the concept of magnetic and electrical flux to IFN. No, I mean integrating flux from zero to infinity. Just kidding but it does make you curious how the name was derived. :facepalm:

Not to be confused with Infinite Flux. :wink:
-------------------------------------------------------------
    As You Like It : Act III, scene II
CORIN: The courtier's hands are perfumed with civet.

TOUCHSTONE: Most shallow man! thou worms-meat, in respect of a
    good piece of flesh indeed! Learn of the wise, and
    perpend: civet is of a baser birth than tar, the
    very uncleanly flux of a cat. Mend the instance, shepherd.
CORIN: You have too courtly a wit for me: I'll rest.
-------------------------------------------------------------
http://www.etymonline.com/index.php?all ... earch=flux wrote:
flux (n.) late 14c., "abnormally copious flow," from Old French flus "a flowing, a rolling; a bleeding" (Modern French flux), or directly from Latin fluxus (adj.) "flowing, loose, slack," past participle of fluere "to flow" (see fluent). Originally "excessive flow" (of blood or excrement), it also was an early name for "dysentery;" sense of "continuous succession of changes" is first recorded 1620s. The verb is early 15c., from the noun.
-------------------------------------------------------------
    King Lear : Act III, scene IV
KING LEAR: Take physic, pomp;
    Expose thyself to feel what wretches feel,
    That thou mayst shake the superflux to them,
    And show the heavens more just.
-------------------------------------------------------------
    Victor Hugo » The Man Who Laughs » Ch. XIV: Ortach
The operation is simple: first the flux, then the reflux; a wave advances, a billow returns.

In such cases the question of life and death is balanced thus: if the wave carries the vessel on the rock, she breaks on it and is lost; if the billow retires before the ship has touched, she is carried back, she is saved.
-------------------------------------------------------------
    John Donne XIV : MEDITATION.
If we consider eternity, into that time never entered; eternity is not an everlasting flux of time, but time is a short parenthesis in a long period; and eternity had been the same as it is, though time had never been. If we consider, not eternity, but perpetuity; not that which had no time to begin in, but which shall outlive time, and be when time shall be no more, what a minute is the life of the durablest creature compared to that! and what a minute is man's life in respect of the sun's, or of a tree?
-------------------------------------------------------------
    Women in Love : D.H. Lawrence: Chapter 13
She was palpitating and formless within the flux of the ghost life.
-------------------------------------------------------------
Art Neuendorffer

NGC3314
Telescope Nerd
Posts: 106
Joined: Thu Sep 23, 2010 5:15 pm

Re: APOD: The M81 Galaxy Group through the... (2017 Jun 27)

Postby NGC3314 » Tue Jun 27, 2017 4:20 pm

Fred the Cat wrote:Permit me the capacity to compare the concept of magnetic and electrical flux to IFN. No, I mean integrating flux from zero to infinity. Just kidding but it does make you curious how the name was derived. :facepalm:


There is actual integration involved. This nomenclature seems to originate from a paper by Alan Sandage reporting faint reflection nebulae in some galaxy fields (including this very field with M81 and M82) from long photographic exposures. He showed (after what the even more senior referee described as correcting his trig, which has certainly happened to me) that the observed brightness made sense for small amounts of dust reflecting not the light of individual stars, but the integrated light of stars in the plane of the Milky Way. To first order, conservation of surface brightness means the dust reflects the same amount of light no matter how far it is "above" or "below" the plane, until that distance becomes a significant fraction of the radius of the galaxy's disk.

User avatar
MarkBour
Science Officer
Posts: 433
Joined: Mon Aug 26, 2013 2:44 pm
Location: Illinois, USA

Re: APOD: The M81 Galaxy Group through the... (2017 Jun 27)

Postby MarkBour » Tue Jun 27, 2017 7:20 pm

A nice image of empty space, today. :-)
Mark Goldfain

Fluxed Up

Re: What the Flux?

Postby Fluxed Up » Wed Jun 28, 2017 2:44 am

neufer wrote: .... flux .... ....flux .... .... fluxus .... ....superflux .... ....flux .... ....reflux.... ....flux .... .... and formless within the flux ....


How fluxstrating

User avatar
Coil_Smoke
Ensign
Posts: 81
Joined: Sun Nov 17, 2013 7:57 am

Re: What the Flux?

Postby Coil_Smoke » Wed Jun 28, 2017 2:04 pm

Fluxed Up wrote:
neufer wrote: .... flux .... ....flux .... .... fluxus .... ....superflux .... ....flux .... ....reflux.... ....flux .... .... and formless within the flux ....


How fluxstrating
All the above posts made for one diversified and intriguing thread. If you/someone had not gone with the "Fluxed Up" bit I was going to have to bring it. :lol2:
Does "Combined Flux" Nebula better describe this phenomena for those not familiar with the nomenclature ? Combining data from multiple instruments has shown us so many new details. This seems to be how astronomy evolves.

Catalina

Re: APOD: The M81 Galaxy Group through the... (2017 Jun 27)

Postby Catalina » Wed Jun 28, 2017 8:22 pm

Is it just an optical response of the human brain or are the stars really lined up in "strings" along the filaments of the gold-ish nebula? Also, what is the blue-ish smudge appearing at about 12:40 near the top edge of the full image?

User avatar
neufer
Vacationer at Tralfamadore
Posts: 13983
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: The M81 Galaxy Group through the... (2017 Jun 27)

Postby neufer » Thu Jun 29, 2017 11:45 am

Catalina wrote:
Is it just an optical response of the human brain or are the stars really lined up in "strings" along the filaments of the gold-ish nebula? Also, what is the blue-ish smudge appearing at about 12:40 near the top edge of the full image?

    1) just an optical response of the human brain
    2) just a galaxy
Art Neuendorffer


Return to “The Bridge: Discuss an Astronomy Picture of the Day”

Who is online

Users browsing this forum: CommonCrawl [Bot] and 1 guest