A galactic harbinger of spring

Most of us think of Groundhog Day as the annual hint that the long winter may soon give way to spring. Astronomers like me prefer a different signpost: The galaxy I call “a galactic harbinger of spring.”

Officially named NGC 2903, the galaxy is a barred spiral similar in size and structure to our own Milky Way. However, the bar in this one looks more like a cosmic dagger thrust through its galactic plane.

NGC 2903 is located a bit west of the head of Leo the Lion. It is the vanguard of the Virgo cluster that features hundreds of galaxies in Leo, Virgo and Coma Berenices. The bulk of the Virgo cluster is best viewed from March through May. The visible part of NGC 2903 is about 100,000 light years in diameter and is 30.4 million light years from Earth.

Roughly 70 percent of NGC 2903’s visible mass is concentrated in the bluish outer regions, which contain the youngest stars, while 20 percent is in the daggerlike bar where older reddishyellow stars reside. Density waves along and through the bar create a burst of star formation that also cause a jumbled disruption of the brownish dust lanes. Two great spiral arms arc gracefully and sweep outward to wispy tidal tails into the darkness of intergalactic space. The central bulge represents about 5 percent of the total visible mass. This is unusually small compared with other spiral galaxies.

There is no sign of a supermassive black hole in the center, not because there isn’t one, but

probably because it is quiescent from our vantage point in space and time. NGC 2903’s galactic plane is tilted 60 degrees from the edge on toward us.

Gary Zientara is a retired airline pilot living in Angel Fire with his wife, Jan. He is a lifelong lover of the night sky, an amateur astronomer/astrophotographer

and a strong advocate for reducing or eliminating light pollution so all of us can continue to enjoy the wonders of the universe.

IMAGE COURTESY MOUNT SANGRE OBSERVATORY NGC 2903 galaxy in the constellation Leo the Lion. It’s on the western edge of the Virgo cluster of galaxies and is visible in small telescopes. This galaxy resembles a sort of “selfie.” If we could instantly travel 1 million light years from Earth, turn around and snap a picture of the Milky Way, this is approximately what it would look like. This image was taken at Mount Sangre Observatory near Angel Fire, NM during the nights of Feb. 12-13.