Arp 194: Merging Galaxy Group
Explanation:
Why are stars forming in the bridge between these colliding galaxies?
Usually when
galaxies crash,
star formation is confined to galaxy disks or
tidal tails.
In
Arp 194, though, there are bright knots of young stars right in a connecting
bridge.
Analyses of images and data including the
featured image of Arp 194 from
Hubble, as well as
computer simulations of the interaction,
indicate that the bottom
galaxy passed
right through the top galaxy within the past 100 million years.
The result has left a stream of gas that is now falling toward the bottom galaxy.
Astronomers hypothesize that stars form in this bridge
because of the recent fading of turbulence after the rapid collision.
In about
a billion years, the galaxies --
including a smaller galaxy superposed on the upper galaxy (see it?) --
will all
merge into one larger galaxy.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
