The Davis Mountains in West Texas are legendary for their dark night skies and they are home to the McDonald Observatory which is well worth a trip to visit.
This image was made from a series of 400 photographs taken over the course of two and a half hours.
The camera is facing Northwest, with the North Star just off the right of the frame and the ecliptic just off the left side, creating a series of peaceful concentric circles as the Earth slowly rotates.
A late night car returning from the McDonald Observatory Star Party lit up the hillside. Either that or it was an alien spaceship's landing lights!
Want to see it in motion? Click the image below!
Just as the Sun moves through the sky, the stars do too!
This is all due to the counter-clockwise rotation of the Earth. Think of the Earth as a 360 degree circle and divide that by the 24 hours that it takes the Earth to make a single rotation. The result is a movement of 15 degrees per hour in a huge arc across the sky from East to West.
Hold out your hand at arm’s length and spread out your index finger and little finger as far as you can (like a wide hook ‘em). That's about 15 degrees and 1 hour of star travel in the sky!
There's a Huge Observatory in Texas!
McDonald Observatory in the West Texas Davis Mountains is connected with the University of Texas and was established in the 1930s. At the time of its construction, its first telescope was the 2nd largest in the world and is still in use today.
The Hobby-Eberly commissioned in 1997 is among the largest in the world. It decodes light from distant stars and galaxies to study their properties.
And here’s the best part… you can visit it!
During the daytime they have excellent programs on space and you can tour the big telescopes. Even better, on certain nights they have Star Parties where you can look through many of the smaller telescopes. It is a bit of a drive, but well worth it (ticket reservations recommended!).
What's in the sky this week?
There are many online resources, I've included a few of my favorites below, plus a link to the observatory's visitor calendar.
Also, McDonald Observatory is a good resource of what is in the night sky. Follow the first button to see their weekly list. Follow the second button for a monthly calendar from SkyMaps that you can download and print out. It highlights what to see each night and which constellations / stars are visible, be sure to download the Northern Hemisphere edition.
Click the buttons below to find out more!
Experiment!
Go outside and align a star to a landmark nearby such as a post or tower. Observe how the star slowly moves over the course of an hour.
Want to do something a bit more advanced? Go back to the same spot a few days later at the exact same time of night. Notice that the star has shifted to the West. This is due to the Earth's revolution around the Sun.