How Fast Do Stars Form?
The speed of star formation from diffuse hydrogen gas has been a subject of strong controversy in the last decade. On one side, it is argued that magnetic fields act to support ionized interstellar gas against gravitational collapse. Then, almost every ion in the gas would need to find an electron to neutralize it before the gas could decouple from the magnetic field and collapse. This would suggest that it takes more than 10 million years to form a star. On the other side, it is argued that gas can slide along the magnetic field lines, allowing gas to accumulate and reach densities high enough for gravity to take hold and cause collapse, dragging the field lines with it. This suggests that a cloud will collapse into a star in only a few million years.
Young stars are deeply embedded within the collapsing clouds of gas and dust from which they form. While dust absorbs the visible light from those young stars, it emits strongly at mid-infrared wavelengths. By studying infrared images of galaxies, the star-forming regions are easily located within a galaxy's spiral arms.

An image of the Whirlpool Galaxy, also known as M51, at 24 microns, with green, 21-cm emission contours from atomic hydrogen gas superimposed. The small offset between the atomic gas and the star formation traced by the mid-infrared image suggests a short time scale for star formation. The image was taken from the Spitzer Infrared Nearby Galaxies Survey (SINGS) using NASA's Spitzer Space Telescope. The 21-cm hydrogen gas emission was measured by The HI Nearby Galaxy Survey (THINGS) team at the Very Large Array radio telescope, an NSF supported facility.
In this study, the rotation of spiral arms through a galaxy is used to directly measure the time scale for star formation. The spiral arms rotate through the galaxy with a measurable speed. Therefore, a measurement of the distance between the peak of the gas emission (green contours) and the peak of the star formation emission (orange), will yield the time it took for the spiral arm to rotate through, and thus the time it took for the stars to form from the gas. The gas emission is observed using the hydrogen 21 centimeter radio emission.
Young stars are deeply embedded within the collapsing clouds of gas and dust from which they form. While dust absorbs the visible light from those young stars, it emits strongly at mid-infrared wavelengths. By studying infrared images of galaxies, the star-forming regions are easily located within a galaxy's spiral arms.
Measuring the relative positions of the star-forming emission versus the hydrogen gas emission in 14 galaxies resulted in time scales ranging from 1 to 4 million years, supporting the argument for fast collapse during star formation.
D. Tamburro, H.-W. Rix, F. Walter, E. Brinks, W. J. G. de Blok, R. C. Kennicutt, Jr., & M.-M. Mac Low
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Is It Still A Universe?
A Whole Bunch of Guesses At:
The Formation of (Many) Irregular Galaxies
The Function of Black Holes
The Explanation of a Multi-Singularity Universe
"Irregular galaxies feature neither spiral nor elliptical morphology. They are often chaotic in appearance, with neither a nuclear bulge nor any trace of spiral arm structure. Collectively they are thought to make up about a quarter of all galaxies. Most irregular galaxies were once spiral or elliptical galaxies but were deformed by gravitational action. Irregular galaxies also contain abundant amounts of gas and dust."
For over ten years I have been puzzled by the explanation of our universe. We have this "Big Bang Theory" which states it all started with the ole singularity.I was only smart enough to come up with two questions regarding this:
1) Isn't a Black Hole also a singularity?
2) Where did all that energy and matter come from?
If a Black Hole is a singularity then wouldn't it blow up in our face into another universe? So I asked my scientific type friends and they had no answers. I sometimes read that it's "a different type of singularity". Huh? Doesn't that destroy the definition of singularity itself?
Then the other day I watched Nova. I went into a dreamy state like when I was in fifth grade and the hot teacher read to us from a good book. A feeling I have not felt in a long time. The Nova episode was about Fractal Geometry.
It would seem that fractals explain a great deal about the structure of nature. Life and non-life. Nature is the universe. The universe is nature. Why then would it not explain the structure of the universe? What if one were to apply fractals to our universe? Then one would probably have to come up with at least one "point of self similarity". The reproduction, the branching, the duplication. If one would apply fractals to the structure of the entire universe it would have to be a point of self similarity on a grand scale. But what if we went to the biggest production we know, the Big Bang?
And that's where it seems to all come together for me. What if, just what if, singularities are the points of self similarity in our MULTIVERSE? What if the "trunk singularity" is what our conceptualized universe comes from? The "branch singularities" are the ones we see in back holes now. The black hole eventually creates a new universe and sort of "disappears" in the process. Seem impossible? Allow me to quote again, "Most irregular galaxies were once spiral or elliptical galaxies but were deformed by gravitational action…..with neither a nuclear bulge nor any trace of spiral arm structure". A spiral galaxy is at the end of the guessed "galactic evolution". What happened to its nucleus? What happened to that black hole? Is there any evidence that a black hole has never "gone away"? What is the evidence of a "disappearing" black hole?
If it's "Exact Self-Similarity" these would be smaller replica universes or "mini universes" (I type as I point my pinky to the corner of my mouth). If it's "Quasi-Self-Similarity" it would be smaller copies in distorted and degenerate forms. So if we were made from a big ole black hole that's where all the wonderful energy and matter came from. Maybe the singularities are very much alike and perhaps only differ in "scale". Like branches on a tree. The answer to "Why don't the singularities we see around us blow up into new universes themselves" perhaps can be answered by the simplest yet hardest to accept answer of, "well, they do". Perhaps we don't see that "explosion" (or "implosion") from our position. Maybe we just see a little part of it and then the black hole fades away. The "explosion (implosion)" forms into "another branch universe" that we just can't see yet (or maybe ever). Perhaps this can help with the concept of parallel universes. Can it help us understand the dark stuff?
If I were to tell you that a universe was created from a singularity then pointed to another singularity and asked you, "What do you think that singularity is going to do?", what is your natural response? What is your inclination? How about the only thing we know for sure...that there would seem to be the distinct possibility that it creates another universe! If I told you an x created a y, and there's another x, what do you think is going to happen?
Universe makes Stars
Stars make Galaxy
Galaxy makes Black Hole
Black Hole makes Universe
(REPEAT)
Universe makes Stars
Stars make Galaxy
Galaxy makes Black Hole
Black Hole makes Universe
(REPEAT)
Universe makes Stars
Stars make Galaxy
Galaxy makes Black Hole
Black Hole makes Universe
(REPEAT)
The thing that scares me about this argument is it is so incredibly simple but tackles a great deal. Things like:
Why is our universe a multi-singularity universe? (Instead of just a one singularity universe - the singularity our universe itself was made from).
What is the function of black holes? WHY do they exist?
Why do black holes "eat"? Could it be they eat for the same reason everything else in the universe eats? To grow and reproduce?
Why do we see galaxies that have appeared to have lost their nucleus? (Is there something else going on other than galaxies smashing into each other).
Is everything cyclical? People make people. Branches make branches. Clouds make clouds. Stars make stars. Universes make universes. No matter where you are everthing goes to the virtually infinitely small and the infinitely large. Our tiny universe does not match on the infinitely large side compared to what we are finding on the infinitely small side.
Any thoughts?