This is a star cluster. By the numbers, it’s about 4,400 light-years away and contains about 500 stars, of which about 150 are particularly bright. It’s young by galactic standards, about 300 million years, compared to our Sun at 4.5 billion or so. The designation M37 refers to Messier object #37. Charles Messier was a French astronomer who was looking for comets in the 18th century. He found many objects that looked like comets at first but turned out to be other things. He decided to make a list of these so as to spare future comet hunters any confusion. Many of his 100 or so objects turn out to be considerably more interesting than comets. They represent a wide variety of astronomical bodies, from galaxies to supernova remnants. Because he found them from France with a telescope that was advanced by his standards but relatively simple by ours, the Messier objects are great targets for beginning astronomers in the Northern Hemisphere. Photographically, such clusters are a bit of a problem, as there is no single item to grab the viewer’s attention. On the other hand, they are a beautiful reminder of just how many stars are out there. With the naked eye, none of this is visible, but the telescope and camera open up a remarkable new set of vistas.
With a medium-size telescope, this giant cloud makes a good claim to be the finest sight in the sky. It’s a huge object in Orion’s belt. Of course ‘huge’ is one of those words that loses its meaning in astronomy. More precisely, this cloud is about 1350 light-years away and about 25 light-years across. The various brightnesses and colors represent different temperatures, densities, and so forth. Basically, this is a star nursery. The gas in this nebula is gradually condensing into stars. If we had time, it would be interesting to photograph it every million years or so and watch as stars evolve.
Here’s a rough shot of perhaps the most unmistakable object in the sky. As rough as the photo is, it serves as a reminder that the experience of first seeing the rings through a telescope is unforgettable. We are bombarded with high-quality pictures from the Hubble and other sources, but the simple act of seeing Saturn and these other objects for your self is still far more moving than anything secondhand.