The Case of the Missing Galaxy


Messier_91_(M91)Messier 91 is a barred spiral galaxy located in the constellation Coma Berenices. It’s part of the Virgo Cluster of galaxies and is about 63 million light-years away from the Earth. It was the last of a group of eight nebulae discovered by Charles Messier in 1781. Originally, M91 was a missing object in the Messier catalogue as the result a bookkeeping mistake by Messier. It was not until 1969 that amateur astronomer William C. Williams realized that M91 was the galaxy that had also be cataloged as NGC 4548.

Image Credit: (CC) Joseph D. Schulman

NGC 3982


NGC 3982NGC 3982 spans about 30,000 light-years, making it about one-third of the size of our Milky Way galaxy. It’s about 68 million light-years away and receding from us at about 1100 km/s. The galaxy is a typical spiral galaxy, and it has a supermassive black hole at its core. It also has a high rate of star birth within its spiral arms. Its bright nucleus contains older populations of stars, which are more densely packed toward the center. The galaxy also has active star formation in the circumnuclear region. NGC 3982 has a mini-spiral between the circumnuclear star-forming region and the galaxy’s nucleus which may be the channel through which gas is transported to the central supermassive black hole from the star-forming region.

Image Credit: ESA / NASA

Walking on the Moon


Aldrin_Apollo_11_(3x5_crop)It’s the 47th anniversary of the first steps by Neil Armstrong and Buzz Aldrin on the Moon. I remember watching Armstrong step onto the Moon while I was lying in my bunk at Ft. Bragg. I was in basic training, and President Nixon had given all federal employees the day off to watch the event. That gave those of us in ROTC Basic a day off which I mostly used to catch up on some sleep. A buddy woke me just in time to see the big event.

Back then, I figured we’d have a permanent base on the Moon and be sending missions to Mars by the second decade of the 21st century, but we’re still stuck in low Earth orbit. Robert Heinlein’s stories such as The Man Who Sold the Moon assumed that space would be developed by private enterprise. It appears that he was correct. I’m betting on SpaceX to get a man to Mars before any agency of any government.