Nebula births baby stars

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What is this? Is it a cosmic catastrophe?

No, it's an area in our Milky Way galaxy that's making baby stars. This close-up image of the Rosette Nebula, taken earlier in April from Mount Sangre Observatory near Angel Fire, shows newly formed stars shining brilliantly in the hydrogen gas nest they were born in.

Vast molecular clouds like this are scattered throughout the graceful spiral arms of our galaxy. Our sun was born in a similar cloud called an HII Region Nebula (HII means ionized hydrogen). The reason we don't see the nebula anymore is our sun is, well, old.

It is a middle-aged star that left its birthplace long ago, about 4.5 billion years in the past. The molecular cloud our sun was born in has since dissipated ,and all of old Sol's siblings have drifted away from each other during the ensuing eons.

The star cluster in the Rosette Nebula (NGC 2244) is filled with newborns "only" 5 million years old. Compared with stellar lifespans, these guys are cosmic infants.

If you study this image closely, you'll find that it is quite animated. The center of the nebula looks like a hole has blown through it. That is indeed the case as stellar winds from the giant variety of bright stars in the middle have literally blown away the gas cloud they were born in.

And these stars aren't happy using only their winds to mess up their nursery. Some of them are running around like energized young children.

One of them can be clearly seen in the above photo plowing through the molecular cloud and leaving a shockwave like the wake a boat makes ("V" shaped feature upper left of center). The tendril-like darker areas, particularly in the lower left half of the gas cloud, are regions where the nebula has collapsed to form denser clumps that will eventually spawn new stars.

You may recall these shapes from the Hubble Space Telescope image called The Pillars of Creation in a similar cloud called The Eagle Nebula. If you look even closer, you'll see some black pepper-like flecks.

Some of them have tiny white halos around them. These are called "proplyds" (PRO-plids), which is an abbreviation astrophysicists use for "protoplanetary disks."

Here, the law of angular momentum has caused a locally dense area of the nebula to swirl into itself like a figure skater when she pulls her arms inward to make herself spin faster. The result is a flattened pizza-like structure with most of its ingredients piled in the center. Getting hungry yet? The center part will eventually get dense enough to light off nuclear fusion and, voila. A star is born.

The outer ingredients of the pizza will form the planets around the newborn star. This explains how our solar system formed with the sun and the planets in a flat plane spinning and orbiting in roughly the same direction.

Uranus is one of the few exceptions. It spins on its side probably because it had a collision early in its formation with another protoplanet that literally knocked it over.

The Rosette Nebula is located in an obscure area of the sky called the constellation Monoceros The Unicorn. It has such dim stars marking it, that it might have gotten its name because it's also difficult to see a unicorn. The Rosette is 5,000 light years away from Earth, and its total width is 130 light years. This image is a close-up of its center, which is "only" 40 light years wide.

Enjoy this view which is a 21-minute stacked exposure of three seven-minute exposures taken through an HA (Hydrogen Alpha) filter and processed using MaxIm DL, an astronomical image processing program.

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