Right in our cosmic backyard, a preview of the Milky Way’s future unfolds.
Just outside the Big Dipper’s “cup,” Bode’s Galaxy, Messier 81, lingers.
12 million light-years away, it’s a naked eye object for those with acute vision and exceptionally dark skies.
The largest galaxy in the M81 group moves ever-so-slightly toward us.
The grand spiral arms and large surface brightness indicate rapid, recent star-formation.
The culprit? Gravitational interactions with other galaxies in its group.
The nearby Cigar Galaxy, Messier 82, is Earth’s closest starburst galaxy.
NGC 3077 also contains young stars, infalling gas, and a distorted morphology.
Radio light reveals neutral hydrogen bridges connecting these M81 Group galaxies.
This galactic triplet is analogous to our Local Group’s Andromeda-Milky Way-Triangulum collection.
The M81 Group contains ~1 trillion solar masses, only slightly below the Local Group’s mass.
Copious star-formation and abundant supernovae are hallmarks of these galaxies.
Gravitational distortion, tidal forces, and gas infall trigger these phenomena.
Modern views reveal a somewhat downsized preview of our upcoming merger with Andromeda.
Overall, the Universe’s expansion drives the M81 Group away.
Owing to dark energy, it will eventually recede from view: the final galactic group to become unreachable.
Mostly Mute Monday tells an astronomical story in images, visuals, and no more than 200 words. Talk less; smile more.