Credit: ESA/Hubble & NASA
Some galaxies are harder to classify than others. Here, Hubble’s trusty Wide Field Camera 3 (WFC3) has captured a striking view of two interacting galaxies located some 60 million light-years away in the constellation of Leo (The Lion).
The more diffuse and patchy blue glow covering the right side of the
frame is known as NGC 3447 — sometimes NGC 3447B for clarity, as the
name NGC 3447 can apply to the overall duo. The smaller clump to the
upper left is known as NGC 3447A.
The trouble with space is that it is, to state the obvious, really, really big. Astronomers have for hundreds of years been discovering and naming galaxies, stars, cosmic clouds
and more. Unifying and regulating the conventions and classifications
for everything ever observed is very difficult, especially when you get
an ambiguous object like NGC 3447, which stubbornly defies easy
categorisation.
Overall, we know NGC 3447 comprises a couple of interacting galaxies,
but we’re unsure what each looked like before they began to tear one
another apart. The two sit so close that they are strongly influenced
and distorted by the gravitational forces between them, causing the
galaxies to twist themselves into the unusual and unique shapes seen
here. NGC 3447A appears to display the remnants of a central bar structure and some disrupted spiral arms, both properties characteristic of certain spiral galaxies. Some identify NGC 3447B as a former spiral galaxy, while others categorise it as being an irregular galaxy.
Source: ESA/Hubble/Potw
