Galaxy caught blowing bubbles
The NASA/ESA Hubble Space Telescope has captured this image of dwarf irregular galaxy Holmberg II. The galaxy is dominated by huge bubbles of glowing gas, which are sites of ongoing star formation. As high-mass stars form in dense regions of gas and dust they expel strong stellar winds that blow away the surrounding material. The cavities are also blown clear of gas by the shock waves produced in supernovae, the violent explosions that mark the end of the lives of massive stars. Credit: NASA & ESA
(PhysOrg.com) -- Hubble's famous images of galaxies typically show elegant spirals or soft-edged ellipses. But these neat forms are only representative of large galaxies. Smaller galaxies like the dwarf irregular galaxy Holmberg II come in many shapes and types that are harder to classify. This galaxy's indistinct shape is punctuated by huge glowing bubbles of gas, captured in this image from the NASA/ESA Hubble Space Telescope.
The intricate glowing shells of gas in Holmberg II were created by the energetic lifecycles of many generations of stars. High-mass stars form in dense regions of gas, and later in life expel strong stellar winds that blow away the surrounding material. At the very end of their lives, they explode in as a supernova. Shock waves rip through these less dense regions blowing out and heating the gas, forming the delicate shells we see today.
Holmberg II is a patchwork of dense star-forming regions and extensive barren areas with less material, which can stretch across thousands of light-years. As a dwarf galaxy, it has neither the spiral arms typical of galaxies like the Milky Way nor the dense nucleus of an elliptical galaxy. This makes Holmberg II, gravitationally speaking, a gentle haven where fragile structures such as these bubbles can hold their shape.
While the galaxy is unremarkable in size, Holmberg II does have some intriguing features. As well as its unusual appearance — which earned it a place in Halton Arp's Atlas of Peculiar Galaxies, a treasure trove of weird and wonderful objects — the galaxy hosts an ultraluminous X-ray source in the middle of three gas bubbles in the top right of the image. There are competing theories as to what causes this powerful radiation — one intriguing possibility is an intermediate-mass black hole which is pulling in material from its surroundings.
This colourful image is a composite of visible and near-infrared exposures taken using the Wide Field Channel of Hubble's Advanced Camera for Surveys.
Provided by
ESA/Hubble Information Centre
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Sep 29, 2011
Rank: 1 / 5 (10)
Although consensus dogma favors condensation and fusion.
Neutron repulsion is the explanation [1].
1. J Cosmology 13, 4187-4190 (2011)
http://journalofc...102.html
With kind regards,
Oliver K. Manuel
Former NASA Principal
Investigator for Apollo
http://myprofile....anuelo09
Sep 29, 2011
Rank: 5 / 5 (6)
Sep 29, 2011
Rank: 1.3 / 5 (12)
Correction : It is theorized/believed that there is ongoing star formation. No one has AFAIK confirmed the formation of ANY star so far. There has been no report of the actual observation of any such formation so how can the researchers/reporters be so sure that stars form in the specified regions? It's sheer speculation at this stage and to pass it off as fact and truth is dis-honest. Or perhaps that doesn't count for much in the evolutionary age anymore?
Sep 29, 2011
Rank: 1.8 / 5 (5)
http://www.scienc..._bubbles
Sep 29, 2011
Rank: 3.4 / 5 (8)
On arrival my courtiers, my heralds will sound their horns in triumph and you will be given 23 virgins (sorry can't match that other faith, bit of a virgin-snatch flow crisis here).
All I demand in exchange is your blind obedience and to no longer make fun of me.
Not to big note myself as that is never my intent, I just had my first Urban dictionary definition published hope you enjoy, my name has been changed to protect my arrogance.
http://www.urband...locallay
Sep 29, 2011
Rank: 1 / 5 (7)
So you concluded that it has no nucleus?
Come on!
Which direction does the solar wind blow?
Galaxies of stars and the stellar photospheres are products of dissociation, fragmentation, fission [1,2].
1. "Neutron Repulsion", The APEIRON Journal, in press (2011)
http://arxiv.org/...2.1499v1
2. "Is the Universe Expanding?" The Journal of Cosmology 13, 4187-4190 (2011)
http://journalofc...102.html
Earlier papers are in my research profile.
Oliver K. Manuel
http://myprofile....anuelo09
Sep 29, 2011
Rank: 5 / 5 (6)
No, not I, Oliver. The NASA Extragalactic Database(NED) lists 334 published refereed papers on Holmberg II between it's discovery in 1956 and 2011: http://ned.ipac.c...of=table
Can you point to ONE paper that discusses observations of a nucleus in Holmberg II? Just one?
I thought not.
Sep 29, 2011
Rank: 5 / 5 (4)
http://www.astrop...2_id.htm
Sep 29, 2011
Rank: 1 / 5 (6)
Would the absence of a nucleus be worthy of note?
Thanks for sharing!
Sep 30, 2011
Rank: 5 / 5 (4)
Well, the *presence* of a nucleus would certainly be of note, as it could provide information on the age, chemical composition and history of the galaxy.
OTOH, the absence of a nucleus would be a problem for those theories that posit all galaxies formed by fragmentation of a "super-neutron star" in their nuclei. Do you have a reference to one of your papers that specifically discusses the formation of galaxies in the absence of a nucleus?
Sep 30, 2011
Rank: 5 / 5 (3)
A 2002 study of Holmberg II produced high resolution maps of the velocity field of HI in the galaxy: http://iopscience....web.pdf
Studying Figs 4 & 5, one would be hard pressed to find evidence of a nucleus in Ho II. In fact, this galaxy shows some minor signs of ram pressure stripping, likely due to minor interactions with the IGM of the nearby M 81 Galaxy Group.
Ho II is a young, starburst dwarf irregular galaxy. If ancient, "nucleus-free" dwarf galaxies are now devoid of their progenitor "super-NSs" (e.g. UMi deG), how do young nucleus-free dwarf galaxies (e.g. Ho II) retain their progenitor "super-NSs" over cosmological time before they begin to fragment to form young (nucleus-free) dwarf galaxies like Ho II?
IOW, how do these primordial, galaxy-forming "super-NSs" survive to present day to fragment and form young, nearby dwarf galaxies?
Oct 19, 2011
Rank: not rated yet
http://holographi...spot.com