Hubble Finds Young Stars in Cosmic Dance

A trio of newborn stars, a mere 1,400 light-years away, are taking part in a complex dance, as revealed by Hubble telescope pictures. Two are now embracing each other, while the third has parted from their company. The Hubble image, taken in infrared and visible light, combined with ground-based radio observations, reveal the trio's activities. These stars reside near their stellar nursery, a huge torus, a donut-shaped object composed of gas and dust. Their location is surprising. Normally, newborn stars are found in the centers of such donuts of material. Apparently, the trio engaged in a gravitational brawl, which kicked them out of the torus.

1. What does the press release picture show?

This composite image, made with two cameras aboard the Hubble telescope, shows a pair of 12 light-year-long jets of gas blasted into space from a young system of three stars. The jet is seen in visible light, and its dusty disk and stars are seen in infrared light. These stars are located near their stellar nursery, a huge torus, a donut-shaped object composed of gas and dust. This torus is tilted edge-on and can be seen as a dark bar near the bottom of the picture. Apparently, a gravitational brawl among the stars occurred a few thousand years ago and kicked out one member (the bright blob above the disk). As a result, the two other stars joined together as a tight double-star system and flew off in the opposite direction. They appear as the red blob below the disk. The huge jet comes from one of the double stars. The star spews out streams of gas in opposite directions, like water from a garden hose. It is not a smooth flow, but happens episodically, creating lumps of gas that fly across space at over one million mph. These gaseous cannonballs catch up with and "rear-end" slower moving blobs, creating a pattern that resembles a string of Christmas lights embedded in the jet.

2. What can scientists learn from this observation?

The observation may provide an important clue to how the masses of stars are determined. Now that the newborn stars are outside the giant donut, they can no longer feed on the rich supply of gas and dust in the abandoned torus. This means they can no longer grow. Thus, in this case, the trio's gravitational interaction determined their final masses. Newborn stars grow -- and at the same time produce giant jets -- by ingesting large quantities of gas and dust. Since both members of the double-star system still produce jets, they must have retained small inner gas disks for fueling the continuing outflow. These inner disks must have been dragged along for the ride as the stars were ejected from the center of the giant torus. But as these small reservoirs are depleted, the remarkable jet activity should begin to fizzle out.