New global map of Earth at night

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This week (April 12, 2017), NASA scientists released the first new global map of Earth at night since 2012. The composite map – dubbed the Black Marble – depicts earthly lights at night as observed in 2016. This nighttime look at our home planet, created using satellite data, provides a unique perspective of human activities around the globe.

Find out more and download images at NASA Earth Observatory’s Night Lights website

View larger. | Image via NASA Earth Observatory/Joshua Stevens/Miguel Román/NASA’s Goddard Space Flight Center.

According to a NASA statement:

The principal challenge in nighttime satellite imaging is accounting for the phases of the moon, which constantly varies the amount of light shining on Earth, though in predictable ways. Likewise, seasonal vegetation, clouds, aerosols, snow and ice cover, and even faint atmospheric emissions (such as airglow and auroras) change the way light is observed in different parts of the world.

The new maps were produced with data from all months of each year. The team wrote code that picked the clearest night views each month, ultimately combining moonlight-free and moonlight-corrected data.

Bottom line: On April 12, 2017, NASA released the new “Black Marble,” the first new global nighttime satellite map of Earth since 2012.

Read more from NASA

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from EarthSky http://ift.tt/2nO1d2d

Please help! Donate to help EarthSky keep going.

Want to donate via PayPal or send a check? Click here.

This week (April 12, 2017), NASA scientists released the first new global map of Earth at night since 2012. The composite map – dubbed the Black Marble – depicts earthly lights at night as observed in 2016. This nighttime look at our home planet, created using satellite data, provides a unique perspective of human activities around the globe.

Find out more and download images at NASA Earth Observatory’s Night Lights website

View larger. | Image via NASA Earth Observatory/Joshua Stevens/Miguel Román/NASA’s Goddard Space Flight Center.

According to a NASA statement:

The principal challenge in nighttime satellite imaging is accounting for the phases of the moon, which constantly varies the amount of light shining on Earth, though in predictable ways. Likewise, seasonal vegetation, clouds, aerosols, snow and ice cover, and even faint atmospheric emissions (such as airglow and auroras) change the way light is observed in different parts of the world.

The new maps were produced with data from all months of each year. The team wrote code that picked the clearest night views each month, ultimately combining moonlight-free and moonlight-corrected data.

Bottom line: On April 12, 2017, NASA released the new “Black Marble,” the first new global nighttime satellite map of Earth since 2012.

Read more from NASA

Enjoy science? Please donate to help EarthSky keep going.

Want to donate via PayPal or send a check? Click here.

from EarthSky http://ift.tt/2nO1d2d