Tuesday, May 27, 2014

Universe in a Box

I just found out about a really excellent Kickstarter project, called "Universe in a Box":

I backed them, and if you want to encourage kids in underprivileged communities worldwide to reach for the stars, maybe you'd like to back them too! Information about the project is available on the Kickstarter page, and you can read a longer post about the project by Markus Pössel here.

When I first heard the title "Universe in a Box", I wondered if it was going to be related to something that blew my mind when I was in grade 5 or so. One of my teachers brought a great big box into the class, and asked us how much we thought could fit in it. After our guesses, she claimed that it was possible to get the entire school building into the box. After we expressed our disbelief, she revealed the trick by getting someone to climb inside, and closing the lid on them. The point was that the "inside" and "outside" of the box are actually relative concepts, and if you want to enclose the entire universe, all you have to do is climb into a big enough box.

Tuesday, May 20, 2014

Aerial images of Berlin at night

It was recently asserted to me that when you look at cities from an airplane you see only lit streets, not dots corresponding to street lamps. My job often involves flying at low altitude over Berlin, and in my experience, there are massive numbers of individual lamps visible from the air. I decided to share some of the photos I've taken that show the "dots". If you're interested in pretty images of monuments from the air at night, look here instead.

The first example is what we'd like to see - the street is lit, but you don't see any dots corresponding to the lamp:

The rest of the examples show that in many places you can see street lights from the air:

Finally, here's an example of the kind of lamp that's a problem - because of the curved glass a lot of light is directly emitted into the sky:

Thursday, May 8, 2014

Possible meteor shower on May 24

Mark your calendars: May 24 is probably the best night of the year to make Loss of the Night app and Globe at Night observations. The reason? Earth is going to pass through the debris ejected by comet 209P/LINEAR in the 1800s.

Leonid Meteor

Since it's not known what the comet was doing in the 1800s, there's a lot of room for surprises. The peak is forecast between 2-4 o'clock in the morning Eastern Daylight Time (8-10 am Berlin time) on May 24th. Since there is considerable uncertainty on when exactly the peak will occur, depending on your location it may be worth going out on both May 23 (late evening), May 24 (early morning) or the early evening of May 24. Use this applet to figure out the most likely best times to observe at your location.

I have seen a number of meteors while using the app, and even once a fireball over Berlin! The next moon free phase runs from approximately May 19-28.

Lighting strategies in England

A number of English councils are experimenting with replacing dusk-till-dawn lighting with a different lighting regime, either involving dimming of lamps, or else switching them off. The Campaign to Protect Rural England has done a survey of councils to try to understand how widespread this practice is, what the councils reasons are, and to learn more about what types of strategies are being used. They've produced a 32 page report summarizing their findings that you can download for free. They've also made the short slideshow below to present the main findings:

Lighting survey results from cpre

If you found that interesting, you may also be interested in a related report submitted to the Department for Environment, Food, and Rural Affairs: A review of local authority road lighting initiatives aimed at reducing costs, carbon emissions and light pollution.

Finally, my group recently published a paper discussing recommendations that we suggest policymakers should adopt in order to reduce energy consumption, and reducing light levels during periods of little activity was one of our recommendations. The paper is unfortunately not open access, but you can download an author's copy from my personal website, Redefining efficiency for outdoor lighting.