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Globe at Night

Main Project Information
Goal Raise awareness about light pollution.
Task Measure the night sky brightness.

Six out of 10 people in the US have never seen our Milky Way Galaxy arch across their night sky from where they live. And the problem of light pollution is quickly getting worse. Within a couple of generations in the U.S., only the national parks will have dark enough skies to see the Milky Way.

Too much outdoor lighting not only affects being able to see the stars, but also wastes energy and money, about 2 to 10 billion dollars a year. And it has been shown to cause sleep disorders in people and to disrupt the habits of animals like newly hatched sea turtles that try to find their way back into the ocean but are disoriented by streetlights.

Light pollution may be a global problem, but the solutions are local. To help people “see the light”, an international star-hunting program for students, teachers, and the general public was created called GLOBE at Night. GLOBE at Night is now in its 6th year and is hosted by the U.S. National Optical Astronomy Observatory.

For 2016 we are collecting your observations during all 12 months of the year! See the dates below and plan to get involved.

January 1-10
February 1-10
March 1-10

March 30- April 8
April 29- May 8
May 29-June 7

June 27-July 6
July 28-August 6
August 25-Sept 2

October 21-31
November 20-30
December 20-30

Through this program, children and adults are encouraged to reconnect with the night sky and learn about light pollution and in doing so, become citizen scientists inspired to protect this natural resource. Teachers like the GLOBE at Night program, because it lends itself to cross-curricular learning: astronomy, geography, history, literature, and writing. The possibilities are great.

As seen in Chapter 4 of Citizen Science by Caren Cooper.

How to Join

The basic GLOBE at Night program is simple: On clear and moonless nights during the two-week campaign, you go outside at least an hour after sunset but before 10 pm local time. Don't stand under or near a light. Wait about 10 minutes for your eyes to get adjusted to the night sky. Then find the constellation, Orion, known for its three distinctive stars that make up Orion's Belt.

You will see Orion toward the South at 8pm and toward Southwest by 10pm, two to three fists (at arm’s length) above your horizon. The stars in Orion are arranged like an hour glass: two stars at the top are Orion’s shoulders, the three stars in the middle are his belt and two stars at the bottom are Orion’s knees.

You then compare what you see to seven stellar images depicting varying degrees of light pollution and choose the chart that most closely resembles what you see. (The charts can be downloaded from the GLOBE at Night website at The first chart has only a few stars (similar to light pollution seen from the middle of New York City). The last chart (#7) shows lots and lots of stars (as seen from a National Park). The charts show progressively fainter stars and therefore more of them, providing a good indication of local light pollution levels. You may also elect to use a Sky Quality Meter, which quantitatively measures the brightness of the night sky. (See for more information.)

After observing, you can log on to the GLOBE at Night Web site, identify the date and time you took the observation, identify your observation location in terms of latitude and longitude with a website tool, and report your observations (e.g., the chart you picked). And that is all. ESRI (the Environmental Systems Research Institute) compiles the information and produces maps for the world to see and teachers to use in lessons about population density, light pollution, geography, and related topics.

Educators and astronomers are hopeful that young stargazers will ultimately draw the same conclusion about their world: The night sky is an irreplaceable natural resource that's worth protecting. One day we can take this data to Congress or to state legislatures to advocate for regulations on artificial light. And then imagine how great the impact will be!

To learn the five easy steps to participate in the GLOBE at Night program and to obtain important information on light pollution, stellar magnitudes, the mythology of Orion, how to find Orion, how to obtain your latitude and longitude, and how to use a Sky Quality Meter, please see All information needed to participate is on the GLOBE at Night Web site, along with downloadable activity guides. The guides have the steps for participating in the program, the different star charts, reporting form and more.

Should you be interested in other activities that have children explore what light pollution is, what its effects are on wildlife and how to prepare for participating in the GLOBE at Night campaign, see the new activities at

Last year, GLOBE at Night collected more than 15,000 measurements of night-sky brightness from kids and adults in 70 countries! Help us exceed these numbers this year!

Participation Fee $0
Expenses $0
Required Gear

1) your eyes,
2) the charts from,
3) a flashlight covered by a red balloon (optional),
4) address of where you are taking the measurement,
5) internet access

Ideal Age Group Elementary school (6 - 10 years), Middle school (11 - 13 years), High school (14 - 17 years), College, Graduate students, Adults, Families
Spend the Time outdoors
Type of Activity At night
Class Materials
Media Mentions
and Publications
Tags light pollution, star
Project Updated 12/23/2016