ASTRONOMY:
Radio Galaxies Return From the Dead
Govert Schilling
Even for deep-space objects, radio galaxies are odd beasts--so odd that scientists have trouble explaining why they exist at all. Now astronomers in the Netherlands have deepened the mystery by discovering that some radio galaxies live twice. In the 21 June issue of the Monthly Notices of the Royal Astronomical Society, they report finding what they call double-double radio galaxies--classic double-lobed galaxies sporting a second, older pair of radio lobes much farther out than the first.