There are billions of galaxies out there, and our galaxy, seemingly so big, is just one of the many. A galaxy is a system of millions or even billions of stars that are all held together by gravitational attraction. There are three different categories of galaxies: spiral, which is what our galaxy is, has long arms that wind towards the bulge that’s at the center ; elliptical, which is just all bulge with no disk or spirals; and irregulars, that have no apparent features or way of categorizing them otherwise. So how come we can’t see all these stars and galaxies in our backyard?
The answer is light pollution. Street lights and other manmade sources brighten the night sky, masking the brightness of the stars. I am really interested in astronomy and love looking at the stars in the sky, but I live really close to the city so there is lots of light pollution where I am. On a good night I usually see 10-15 stars, which is very different from my groupmate, Abbey, who lives out in the country and sees a couple hundred stars. As well as making it hard to observe the universe, light pollution affects animals.
Light pollution affects animals ecosystems in many ways. The rhythm of life is dictated by the natural patterns of light and dark, and pollution disrupts that pattern causing impacts on ecological dynamics. It can also confuse the migratory patterns of birds and other animals, as well as change predator-prey relationships, which in turn affect the population changes with those animals. Now there is a way to help keep track of how much light pollution your area has, and contribute to a global brightness map.
Globe at Night is a citizen science project that I am working on. It focuses on light pollution and how much different locations are getting based on star count. On its website I’ve learned so much more about light pollution and how much it can really affect the world. Along with this I am doing Galaxy Zoo which is a citizen science project that allows people to help classify the galaxies that the Hubble Space telescope is finding. Because it is so hard to find a place with a low enough amount of light pollution to observe galaxies they use the Hubble telescope in space because there is NO light pollution there. I hope to have fun doing these citizen science projects, as well as learn something new.