Starship Asterisk*

Case wrote:

K1NS wrote:
Forgive my pedantry, which obscures the point of this beautiful image, but instead of saying "against a backdrop of central Milky Way stars," I believe the caption should read "behind a foreground of central Milky Way stars."

I think the original caption is quite accurate when looking “from above” at the situation. The stars in the center of the Milky Way, even a whole arm, are behind M17 from our point of view.

K1NS wrote:Forgive my pedantry, which obscures the point of this beautiful image, but instead of saying "against a backdrop of central Milky Way stars," I believe the caption should read "behind a foreground of central Milky Way stars."

NoelC wrote:
I have a question though... What's making it greenish, just above center?
Green is so uncommon in astronomy, that this really jumps out at me.

neufer wrote:

---

Chris Peterson wrote:

K1NS wrote:
Forgive my pedantry, which obscures the point of this beautiful image, but instead of saying "against a backdrop of central Milky Way stars," I believe the caption should read "behind a foreground of central Milky Way stars."

Or perhaps, "embedded in a sea of central Milky Way stars", as we see stars both in front of and behind the nebula.

Great A'Tuin

Great A'Tuin is the Giant Star Turtle (of the fictional species: Chelys galactica) who travels through the Discworld universe's space, carrying four giant elephants (named Berilia, Tubul, Great T'Phon, and Jerakeen) who in turn carry the Discworld. The narration has described A'Tuin as "the only turtle ever to feature on the Hertzsprung-Russell diagram."

Great A'Tuin's gender is unknown (though in The Colour of Magic Pratchett describes the turtle as male), but the subject of much speculation by some of the Disc's finest scientific minds. The sex of the World Turtle is pivotal in proving or disproving a number of conflicting theories about the destination of Great A'Tuin's journey through the cosmos. If, as the Discworld version of the popular "big bang theory" states, Great A'Tuin is moving from the Birthplace to the Time of Mating, then at the point of mating the civilizations of the Disc might be crushed, simple slide off, or else the entire world will end. The hypothesis is that all stars in the sky are obviously also worlds carried by giant turtles, and that when all the turtles meet they will mate passionately, for the first and only time; from that mating, it is hypothesized that new turtles would be born to carry a new pattern of worlds. Attempts by telepaths to learn more about Great A'Tuin's intents have not met with much success, mainly because they did not realise that its brain functions are on such a slow timescale. All they've been able to discern is that the Great A'Tuin is looking forward to something.http://en.m.wikipedia.org/wiki/Discworld_(world)

NoelC wrote:What a beautiful nebula when shown in all its full extent. Wow.

I have a question though... What's making it greenish, just above center? Green is so uncommon in astronomy, that this really jumps out at me.

And with all due respect to Mr. Gendler, I believe he may have de-emphasized the stars a bit too much in this, digging dark holes in the sky around them and making them anything but white. Never forget that stars are beautiful too, just as they are! In this particular image, since the bright ones are mostly out at the extremities, allowing them to be brilliant doesn't take detract from the nebula at all.

-Noel

Chris Peterson wrote:

K1NS wrote:
Forgive my pedantry, which obscures the point of this beautiful image, but instead of saying "against a backdrop of central Milky Way stars," I believe the caption should read "behind a foreground of central Milky Way stars."

Or perhaps, "embedded in a sea of central Milky Way stars", as we see stars both in front of and behind the nebula.

K1NS wrote:Forgive my pedantry, which obscures the point of this beautiful image, but instead of saying "against a backdrop of central Milky Way stars," I believe the caption should read "behind a foreground of central Milky Way stars."

ta152h0 wrote:when a star decides to go KABOOM !does it do this in miriads of smaller kabooms all at once, possibly explainig all the filaments and other various shapes we see in this image and like the Tarantula nebula ? Called " pinging " when it happens in my FORD .

ta152h0 wrote:when a star decides to go KABOOM !does it do this in miriads of smaller kabooms all at once, possibly explainig all the filaments and other various shapes we see in this image and like the Tarantula nebula ? Called " pinging " when it happens in my FORD .

The nebula contains a large amount of dark obscuring material, which is obvious in its remarkable features. This matter has been heated by the hidden young stars, and shines brightly in infrared light.http://messier.seds.org/m/m017.html

The dark dust filaments that lace the center of Omega Nebula were created in the atmospheres of cool giant stars and in the debris from supernova explosions. http://apod.nasa.gov/apod/ap040208.html

Core-collapse Supernovas

The general picture for Type II, Type Ib and Type Ic supernovas - also called core-collapse supernovas - goes something like this. When the nuclear power source at the center or core of a star is exhausted, the core collapses. In less than a second, a neutron star (or a black hole, if the star is extremely massive) is formed. The formation of a neutron star releases an enormous amount of energy in the form of neutrinos and heat, which reverses the implosion. All but the central neutron star is blown away at speeds in excess of 50 million kilometers per hour as a thermonuclear shock wave races through the now expanding stellar debris, fusing lighter elements into heavier ones and producing a brilliant visual outburst that can be as intense as the light of several billion Suns.

Thermonuclear Supernovas
Type Ia supernovas, in contrast, are observed in all kinds of galaxies, and are produced by white dwarf stars, the condensed remnant of what used to be sun-like stars. A white dwarf star, a dense ball primarily composed of carbon and oxygen atoms, is intrinsically the most stable of stars, as long as its mass remains below the so-called Chandrasekhar limit of 1.4 solar masses.
If, however, accretion of matter from a companion star or the merger with another white dwarf, push a white dwarf star over the Chandrasekhar limit of 1.4 solar masses, the temperature in the core of the white dwarf will rise, triggering explosive nuclear fusion reactions that release an enormous amount of energy. The star explodes in about ten seconds, leaving no remnant. The expanding cloud of ejecta glows brightly for many weeks as radioactive nickel produced in the explosion decays into cobalt and then iron.http://chandra.harvard.edu/xray_sources/supernovas.html

ta152h0 wrote:when a star decides to go KABOOM !does it do this in miriads of smaller kabooms all at once, possibly explainig all the filaments and other various shapes we see in this image and like the Tarantula nebula ? Called " pinging " when it happens in my FORD .