Credit: ESA/Hubble & NASA
Acknowledgement: Kathy van Pelt
This image shows galaxy NGC 4485 in the constellation of Canes
Venatici (The Hunting Dogs). The galaxy is irregular in shape, but it
hasn’t always been so. Part of NGC 4485 has been dragged towards a
second galaxy, named NGC 4490 — which lies out of frame to the bottom
right of this image.
Between them, these two galaxies make up a galaxy pair
called Arp 269. Their interactions have warped them both, turning them
from spiral galaxies into irregular ones. NGC 4485 is the smaller galaxy
in this pair, which provides a fantastic real-world example for
astronomers to compare to their computer models of galactic collisions.
The most intense interaction between these two galaxies is all but over;
they have made their closest approach and are now separating. The trail
of bright stars and knotty orange clumps that we see here extending out
from NGC 4485 is all that connects them — a trail that spans some 24
000 light-years.
Many of the stars in this connecting trail could never have
existed without the galaxies’ fleeting romance.
When galaxies interact
hydrogen gas is shared between them, triggering intense bursts of star
formation. The orange knots of light in this image are examples of such
regions, clouded with gas and dust.
A version of this image was entered into the Hubble’s
Hidden Treasures image processing competition by contestant Kathy van
Pelt, and won sixth prize in the “basic image searching” category.
Source: ESA/Hubble - Space Telescope
