The Jets of NGC 1097
Enigmatic spiral galaxy NGC 1097 shines in
southern skies, about 45 million light-years away in the chemical constellation Fornax. Its blue
spiral arms are mottled with pinkish star forming regions in this colorful
galaxy portrait.
They seem to have
wrapped around a small companion galaxy below and left of center, about 40,000
light-years from the spiral's luminous core.
That's not NGC 1097's most
peculiar feature, though. The very deep exposure hints of faint, mysterious
jets, most easily seen to extend well beyond the bluish arms toward the lower
right.
In fact, four faint jets are ultimately recognized in
optical images of NGC 1097. The jets trace an X centered
on the galaxy's nucleus, but probably don't originate there. Instead, they
could be fossil star
streams, trails left over from
the capture and disruption of a much smaller galaxy in the large spiral's
ancient past.
