The City Dark Comes to Tucson (& Maybe Near Where You Live Too)

The City Dark, an award-winning film about light pollution will soon be playing in Tucson, Arizona.

The film is a feature documentary about light pollution and the disappearing night sky. After moving to light-polluted New York City from rural Maine, filmmaker Ian Cheney asks: "Do we need the dark?" Exploring the threat of killer asteroids in Hawai'i, tracking hatching turtles along the Florida coast, and rescuing injured birds on Chicago streets, Cheney unravels the myriad implications of a globe glittering with lights—including increased breast cancer rates from exposure to light at night, and a generation of kids without a glimpse of the universe above. Featuring stunning astrophotography and a cast of eclectic scientists, philosophers, historians, and lighting designers, THE CITY DARK is the definitive story of light pollution and the disappearing stars.

Featured in the documentary are astrophysicist Neil deGrasse Tyson, astronaut Don Pettit, astrophotographer Jack Newton, University of Arizona cosmologist Chris Impey & more.

The screening will be held at The Loft Cinema on Tuesday, January 24th at 7:00 p.m.  Admission is $10 ($8 for Loft members) and a proceeds for this screening will go to help support the International Dark Sky Association. Director Ian Cheney will be on hand for a Q & A following the show. There will be cool astronomy prizes too from the Mount Lemmon SkyCenter and Kitt Peak National Observatory.

Don't worry if you wont be near Tucson the night of the 24th, as The City Dark will have screenings in many cities.  Check out the full list here.

Be sure to check out the trailer for the film:

Casting the 2nd GMT Mirror

Early reports confirm that Saturday's casting at the University of Arizona's Mirror Lab of the second mirror for the Giant Magellan Telescope was successful.

Here is a short video of the rotating oven in action:

 Recall that inside the rotating oven was placed some 21 tons of chunks of borosilicate glass onto a mold. Here is a shot taken by one of the cameras inside the oven from early in the process:

 Compare it with this recent photo:

 The glass has melted into into the honeycombed structure of the mold.  It is not really evident here, but the rapid rotation of the oven has introduced a curve to the liquid glass.

Upon cooling the mirror will eventually be removed and inspected.  If all is will it will be placed in line for polishing.  The first mirror cast for the GMT is still being polished in the lab and here is a timelapsevideo of it being polished that was cast for this project:

This video comes from Dean Ketelsen. Be sure to check out his great blog.

Measure Light Pollution with GLOBE at Night

It is almost time to get outside and start measuring light pollution.  GLOBE at Night starts tomorrow night and runs through January 23rd. It is a very easy & fun citizen science campaign.  All of the details are on their website.

What is the whole point? To get outside under the stars and raise public awareness of the impact of light pollution. From their website:

Light pollution threatens not only our “right to starlight”, but can affect energy consumption, wildlife and health. The GLOBE at Night campaign has run for two weeks each winter/spring for the last six years. People in 115 countries have contributed 66,000 measurements, making GLOBE at Night one of the most successful light pollution awareness campaigns.

I will be observing and reporting nightly. How about you?

Watch the GMT's 2nd Mirror be Cast this Saturday

Back in November I posted about a tour I received of the University of Arizona Steward Observatory Mirror Lab.

On Saturday, January 14th the Mirror Lab will be casting the second of seven 8.4 meter mirrors for the Giant Magellan Telescope.  See the press release for the event here.

They have placed 21 tons of borosilicate glass into a mold that is sitting within a giant rotating oven. As the temperature increases, the glass will melt, and the rotation will evenly spread the molten glass over the mirror's honeycomb skeleton.

The Mirror Lab has set up live webcams inside the oven, will relay oven temperature and rotation speeds telemetry for the mirror casting. You will be able to watch the event as it unfolds here:

http://abell.as.arizona.edu/~hill/GMT2/

Times have changed and the methods of casting telescope mirrors has too. Here's how Corning Glass Works cast the mirror for the 200-inch telescope back in 1934:

Times have changed.

2012: the End of the World? Nope!

One of the tasks at my old job was answering astronomy questions that were sent in to the observatory. This included real questions that covered everything from the annual Mars Hoax to detailed questions about telescopes, eclipses and more.

Over the last several years included in the questions were ones about the end of the world, 2012, "Planet X" (aka Nibiru, Eris), the "alignment" with the galactic center and others - none of which are real. It is unfortunate that so many people have been taken in by the 2012 end of the world hoax.

Since I moved on to another position, I no longer get those questions, but it is still important for the truth to be circulated and this video explains it all very nicely.

Check out the script here and be sure to see the Top 10 Reasons Why the World Won't End in 2012. Help spread the truth and stop the insanity.