Arp 87: Merging Galaxies from Hubble
Explanation:
This dance is to the death.
Along the way, as these two large galaxies duel, a
cosmic bridge of stars, gas, and dust currently stretches
over 75,000 light-years and joins them.
The bridge itself is strong evidence
that these two immense star systems have
passed close to each other
and experienced
violent tides induced by mutual gravity.
As further evidence, the face-on spiral galaxy on
the right, also known as NGC 3808A,
exhibits many young blue star clusters produced in a burst
of star formation.
The twisted edge-on spiral on the left (NGC 3808B) seems to be wrapped
in the material
bridging the galaxies and
surrounded by a curious
polar ring.
Together, the system is known as
Arp 87
and morphologically classified, technically, as
peculiar.
While such interactions are drawn out over billions of years, repeated
close passages
should ultimately result in the death of one galaxy in the sense that
only one galaxy will eventually result.
Although
this scenario
does look peculiar, galactic mergers are thought
to be common, with Arp 87 representing a stage in
this
inevitable process.
The
Arp 87 pair are
about 300 million light-years
distant toward the constellation Leo.
The
prominent edge-on spiral
galaxy at the far left
appears to be a more distant background galaxy and
not involved in the on-going merger.
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.
