Under The Dipper’s Handle, Part 2

Not far from Cor Caroli and La Superba, which we saw in the last issue, you’ll find three far more distant objects: the spiral galaxies M94, M63, and the famous Whirlpool galaxy M51.  Here’s part two of our tour of the sky under the Dipper’s handle.

The Basics

• The showpiece object of this area is M51, the Whirlpool Galaxy.  M51 interacts gravitationally with the nearby galaxy NGC5195.  Both can be seen in the same field of view just 3 degrees southwest of Alkaid, the tip of the Dipper’s handle.  A bridge of stars connects the two galaxies.

• M51 is an elegant face-on spiral galaxy just 15 million light-years away.  NGC5195 is a dwarf elliptical distorted by its more massive companion.  Lord Rosse was the first to glimpse the spiral structure in M51 with his massive telescope in the Irish countryside.

• In photographs of M51, you can see the blue spiral arms and clots of pink nebula where new stars are born.  The view through a telescope is far more modest.  It takes at least an 8-10 inch scope to see even a glimpse of the spiral structure in dark sky.  If you’re in the city, sadly, you’ll only see the fuzzy nuclei of each galaxy.

M51 and NGC5195 through a really big telescope.

A Deeper Look

• From Cor Caroli, look 1.5 degrees northeast of the midpoint between Cor Caroli and beta Canes Venaticorum (Chara).  There you’ll find M94, another face-on spiral that in long-exposure photographs looks like the clouds of a hurricane seen from above.  In a small scope, you ‘ll see a bright nucleus and diffuse circular disk.  As with most galaxies, more aperture and magnification help, as does clear dark sky.

•With a scope larger than 6-8 inches, in perfect sky, you may see a faint ring around M94.  This is a region of strong star formation.  It gives the galaxy the appearance of a bone-white eye staring back at you.

• Now turn northward of Cor Caroli by 5 degrees to find M63, the Sunflower galaxy.  This is a loose spiral with finely detailed arms splaying out like flower petals.  Look carefully to tease out as much detail as you can.

Where to find M51, M63, and M94 (click to enlarge)

Good To Know

The vortex of M51 led astronomers like John Herschel to speculate that M51 was a new solar system in the early stages of formation.  Its true nature, and that of all galaxies, was not discovered until the 1920′s.

Personal View

Looking at the fine structure of galaxies is an acquired taste that requires patience and skill.  If you were spoiled over the past few months looking at the bright stars of winter, you may wish to review fine art of seeing faint objects through a telescope.

To be continued… There are two more galaxies worth exploring under the Dipper’s Handle… we will tour them in the next issue.