
Stirred by the gravitational pull of other near by galaxies such as NGC 4668 (lower left of image), NGC 4666 is pumping out new generations of stars. Very active star-forming galaxies like this are known as starburst galaxies. Starburst galaxies are exciting, turbulent places. Strong stellar winds from giant new stars in the starburst region combine with the the blasts of supernovae to push a mighty flood of hot gas, a "superwind" from the galaxy thousands of light years into intergalactic space. Alas the superwind is too tenuous to see in visible light, but has been observed in X-rays. There is much, much more to the Universe than meets the eye.
Image Credit: ESO