Bad Neighbor
 Strong winds from nearby young stars are eroding a cloud of gas and dust in the nebula IC 1396. The winds, which are moving from lower left to upper right, squeeze the cloud, helping it give birth to new stars. At the same time, they blow away much of the raw material for stars, limiting the number of stars that can be born. This infrared image, from Spitzer Space Telescope, shows the glow of the gas and dust, which appear dark to the naked eye. [NASA/JPL/W.Reach (SSC/Caltech)]
An example is found in the stellar nursery known as IC 1396. It's about 2500 light-years away in the constellation Cepheus, which arcs high across the north this evening.
IC 1396 is a big cloud of gas and dust. Parts of the cloud have collapsed, giving birth to new stars. The most prominent is a member of the hottest and most massive class of stars. It's dozens of times more massive than the Sun, and tens of thousands of degrees hotter.
Ultraviolet energy from the star causes hydrogen gas in the surrounding cloud to glow like a fluorescent bulb. But it also acts like a blowtorch, blasting away any nearby blob of material. This shuts down the process of star formation by eroding the dense clumps of gas and dust that are collapsing to form new stars.
The heavy star is also stripping away the raw material for planets from a nearby star that has formed.
A team of astronomers from Arizona, using observations by Spitzer Space Telescope, found that a stream of dust is blowing away from the neighboring star, which is similar to the Sun. The tremendous heat of the bigger star boils away the gas and dust that encircles its smaller companion. Its radiation then blows the evaporated material into space -- leaving the star unable to give birth to planets.
Script by Damond Benningfield, Copyright 2006
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