Eyes Full Of Stars

A headline that could have been printed in 1613, but Neptune’s actual discovery wasn’t announced until over two hundred years later.

During December of 1612 and the following January, Galileo was hard at work with his telescope observing Jupiter and its moons. In his logbook, he sketched the planet and the movement of its satellites. He also included the positions of background stars that shared the field of view. During the course of his observations, the location of one of those stars changed. Galileo noticed the shift in position, but stayed on task studying Jupiter.

I just returned from a week out in the extreme west end of the Oklahoma panhandle and the annual Okie-Tex star party. Besides being home to the highest elevation in the state atop the Black Mesa, this part of the panhandle is also the location of the town of Kenton. The only town in Oklahoma that observes the Mountain time zone.

Including this most recent trip, I have been to Okie-Tex 5 times. A star party is a gathering of several hundred astronomy buffs, both professional and amateur, that can last for a few days to a week or longer. Along with telescopes of all shapes and sizes, activities common to star parties are educational sessions, door prize giveaways and in some cases, contests for best amateur telescope making and best photography of night sky objects.

170 years ago, Sir John Herschel exposed the first glass plate photograph. The subject was the 40 foot telescope used by his father, William Herschel. The elder Herschel discovered Uranus in 1781. And in collaboration with his sister, Caroline,  he observed numerous comets and thousands of nebulae and star clusters. To make his photograph, John Herschel used a silver chloride solution. But the processing method was so time-consuming and tedious that it wasn’t widely adopted.

Do you like mystery? This month, one of the most puzzling variable stars in the sky will dim for the first time in 27 years. It is epsilon Aurigae in the constellation Auriga, the Charioteer. With an estimated distance of 2,000 light years, epsilon Aurigae is a variable star. But, the star’s variability isn’t the odd part.

Astronomers have cataloged thousands of variable stars with cycles ranging from hours to days at a time. Some stars, like the Cephied variables, pulsate in brightness due to changes in opacity of their outer layers. Other variable stars are eclipsing binary systems. The star Algol, in the constellation Perseus, is a famous example. With the regularity of clockwork, Algol’s luminosity plunges every 2.9 days. It then rebounds to full brightness in just a few hours.