10 Famous Astrophotography Targets

1. The area in and around the Horsehead is filled with gigantic stars and huge clouds of gas and dust. The radiation from the stars heats the surrounding gas, causing it to glow. Clouds of gas that glow in this way are called emission nebulae. The red area behind the Horsehead is an emission nebula.
2. The Horsehead figure is a dark nebula. Dark nebulae are cold clouds of gas and dust. They're called dark because they have no light of their own. A dark nebula is the silhouette of a cold cloud of dust.
3.  The small blue object just to the left of the Horsehead is a reflection nebula. It glows because it's able to scatter some of the light from the stars around it. Reflection nebulae are usually blue because red light doesn't scatter easily. The same type of effect causes the sky to appear blue.

The Whirlpool galaxy is currently in the process of merging with a smaller galaxy designated as NGC 5195. The two galaxies have already passed through each other once, and the interaction has spurred a surge of star formation in both galaxies. The center of the Whirlpool is home to a 160 billion solar mass black hole. The black hole is busy gobbling up any thing that gets too close. 

The galaxy is in turmoil. Gavity is sqeezing the cold clouds of gas causing some of them to colapse and form new stars. The large young stars give the galaxy a bright blue glow. Even at a distance of 23 million light-years it appears incredibly bright.

It was August 21, 2017 and we were camping at Guernsey State Park in Wyoming. The excitement had built all morning as the moon slowly blocked more and more of the sun. At first, the change was barely noticeable, but as the hours passed, the pace of change quickened. In the final moments before totality, all the phases of a normal evening were compressed into several minutes. The birds prepared to roost, and the crickets started to chirp. 

When the Moon swallowed up the last piece of the sun, the temperature dropped instantly, and a chilly wind began to blow. Day turned into night, and a few stars twinkled in the sky. One of my friends shouted, "There's Venus!" For the next two minutes, the crowd oohed and aahed as the surreal event unfolded. 

The finale came when a tiny piece of the sun reappeared and created a perfect diamond ring effect. It only lasted two seconds, but they were two seconds we would never forget.