The Half-Astrophysicist Blog

National Dark Sky Week

April 20th to the 26th marks National Dark Sky week.  Started in 2003, its goal is to raise awareness of good outdoor lighting to help preserver our natural dark skies (yes, dark is the natural state of night although it can be hard to believe at times).   Dark Sky Week is endorsed by the International Dark-Sky Association, the American Astronomical Society, the Astronomical League, and Sky & Telescope.

To see the full extent of the problem, let’s take a look at satellite measurements of artificial lighting from the World Atlas of Artificial Lighting.

As you can see, everything in the east of the US through the midwest is pretty socked in.  The west still has a few dark areas but they are rapidly being threatened as well.  Cities such as Las Vegas and Phoenix have lights that can be seen from hundreds of miles away.

The International Dark Sky Association has all kinds of great info on the effects of bad lighting on wildlife and human health.  Fortunately, good outdoor lighting can help a lot and even save money in the long run.

For a little humor for Dark Skies Week, you can watch the Simpsons episode, Excuse Me While I Miss the Sky where Lisa leads the crusade against light pollution.

April 20, 2009 Posted by halfastro | Dark Skies, Environment | | No Comments Yet

Earth Hour: The Big Picture

Many people celebrated (and some derided) Earth Hour last Saturday night.  Landmarks in major cities around the world went dark and people were encouraged to join in.  I was at the U of Arizona Mall with my telescope at a star party.  Here is an pic of the event (click to embiggen).

earthhour090001I couldn’t do before and during pictures since the streetlights never came on and I didn’t feel like waiting until they were turned back on afterwards.

This week the Boston Globe’s Big Picture featured images from Earth Hour Around the world. Be sure to click on the images to see the cities go dark.  It’s pretty interesting to see the differences.

April 4, 2009 Posted by halfastro | Astrophotography, Dark Skies, Environment | | No Comments Yet

Turn Out the Lights: It’s Earth Hour

Tonight, March 28th, people in cities around the world will turn off their lights in honor of Earth Hour. And it really is an hour: from 8:30pm to 9:30pm local time.  Cities across the USA and the world are participating, turning off as many outdoor lights as they can (lights critical for safety are not turned off, of course!)  Major US landmarks are going dark including Broadway and the Vegas Strip (that I want to see!)

You are encouraged to take photos or videos of the event and upload them.  Blogging and Twittering are also encouraged.

As for me, I will be manning a telescope at a star party at the University of Arziona in Tucson. We have some people around town with light meters who will try to measure potential changes as well as photographers at strategic points around town taking pictures before, during and after Earth Hour.  Earth Hour is a major event in Tucson, which is one of the best cities in the country for its outdoor lighting policies.

Now if I can’t appeal to your sense of environmental awareness and responsibility guys, chicks dig candleliht dinners for a cause.  It might help you tomorrow night in another department if you know what I mean!

So turn out the lights, just for an hour.

March 28, 2009 Posted by halfastro | Dark Skies, Environment, citizen science | | No Comments Yet

GLOBE at Night Wants You

globe-at-nightGLOBE at Night (GAN), our annual dark skies campaign, is about to ramp up for 2009.  GLOBE at Night will start on March 16th and culminate on March 28th in conjunction with Earth Hour.

GLOBE at Night is a citizen science campaign to raise awareness of light pollution and collect data on how bright the night sky is at various locations around the world.  Anyone can participate and contribute data (and it is a good project to get students involved in, teachers!)

The procedure is simple.  Go outside on a clear night from March 16th to the 28th and find the constellation Orion in the southwest.  The GLOBE at Night website has magnitude charts (which I have included below…click to embiggen).

magchartsIf you have a bright sky with a lot of light pollution, you might see something like the magnitude 1 or 2 chart.  If you are lucky and live in a dark site, you would see the magnitude 5 or 6 chart.  Simply select which chart most closely matches what you can see in the sky.  That’s your data.  You then go to the web and report your data. The report form will be on up March 16th when the campaign starts.  You will also be asked for your latitude and longitude as well as the local time.  You can find your latitude and longitude using a variety of online tools or a GPS system.  Once you have entered your data, you can zoom in on your city and see your data as well as data collected by others around you.

You can (and are encouraged) to take lots of observations.  We need lots of measurements in suburbs, city centers, parks, the countryside, everywhere.  I take some nightly bike rides during GLOBE at Night and make measurements every half mile, taking different routes each time.  I have a small GPS system I use to track my runs and use an MP3 voice recorder to record my data.  I can canvas dozens of square miles over the course of a few nights.

So why should you care about dark skies?  Won’t decreasing light make the night more dangerous?  Well, lights pointing up = energy wasted.  The least we can do is shield lights and be sure they point downward.  Second, very bright lights create lots of glare to the point that too much light can decrease safety.  Glare can make it difficult to see pedestrians on the street and stop signs.  Wasting energy and money and decreasing safety makes no sense.

Poor lighting effects wildlife in many ways.  It can disrupt mating patterns of certain animals, disorient birds, and we know they can attract insects!  Research is well underway on the effects of excess nighttime lighting on human health including studies indicating increased cancer risks.

Fortunately, this is a problem that can be solved and save money at the same time.  Lighting companies make lots of high quality, well shielded lights that cost no more than poorly designed fixtures. Many cities are passing lighting ordinances and will be installing shielded street lights as their old ones wear out.  The International Dark Sky Association has sample lighting ordinaces and lots of information on good lighting design.

The first steps are raising awareness and collecting data.  So please take a few minutes the next couple of weeks and contribute a little piece to this ongoing project!

March 11, 2009 Posted by halfastro | Astronomy, Environment, citizen science | | 1 Comment

Satellites in Collision

There have been small objects colliding in space before, but now we have two full fledged satellites that have run into each other. An Iridium communication satellite collided with an old Russian Cosmos Communication satellite. This collision created hundreds of new pieces of debris that could in turn collide with other satellites. The collision occurred about 500 miles over Siberia.

The first thing most people are concerned about is the International Space Station or Hubble. Both of these orbit a lot lower, so they are not in immediate danger from this debris. However, there are a lot of satellites in similar orbits to these to that are now at increased risk of collision with space debris.

A company called Analytic Graphics created a pretty neat animation of the collision and the resulting debris cloud (based computer models of course).

You can see the debris spread out fairly quickly. When they add all the other objects up there it starts looking pretty crowded.

You can even listen for radar echos from the debris cloud.  Spaceweather is streaming the Air Force Space Surveillance Radar signals from Texas.  The next time to listen is 11:56pm to 12:07am EST tonight.

February 12, 2009 Posted by halfastro | Environment, general science | | No Comments Yet

Going Green at the Grocery Store

Yep, I am going to risk getting a little environmental on you here.  I just got back from my weekly grocery run and made the switch to canvas bags last summer.  I am finally to the point where I remember them on a regular basis rather than running back to my car halfway through shopping.

I am sure we all know the benefits…fewer plastic bags (which take oil to make) less waste, etc.  If you are not convinced, let me appeal to your inner lazy American: canvas bags hold more and with the nice handles, they are so much easier to carry!  So not only are plastic bags wasteful, they are also more work…that just doesn’t make sense.

I didn’t even half to pay for my bags.  I just took all the bags I have received at different meetings and conventions I attended and started using them.  I frequently get comments from the baggers about where I have been and what I obviously do for a living!

Some stores give a small discount if you bring your own bags.

I know it will be difficult to totally eliminate the plastic bag…I still get some occasionally (especially when traveling).  I probably have reduced my usage of them by close to 90%.  Now we just have to all do that and we will take one of many small steps necessary to attain a sustainable lifestyle.

January 26, 2009 Posted by halfastro | Environment | | No Comments Yet