Orion is always tops on a list of people's favorite constellations. Yet its disappearance is welcome for it signals the return of spring.
There are many things that herald the beginning of spring to different people. Some people see the return of birds such as robins as a sign of spring. Others look for bulbs poking through the dirt. But amateur astronomers see Orion disappearing in the west as a sign of spring.
At the end of April, after the sun sets in the west, the sky grows dark and the constellation Orion remains above the horizon. It will follow the sun down, with the bright star Rigel leading and Betelgeuse disappearing last.
Take your last chance to view the Orion Nebula. Nearby, other winter sights are setting for the season. The Pleiades star cluster is also doing down, as is the brightest star in the sky, Sirius.
The entire Milky Way itself, along with all its thick star clusters and nebulas, is sinking toward the horizon. Looking into our galaxy from the side shows us many beautiful deep-sky objects, including those in Orion. But the deepest deep-sky objects are best seen in spring away from Orion, looking out away from our galaxy and into the depth of space, where galaxies and clusters of galaxies lie.
Good-bye winter's Orion, hello spring galaxies!
