NASA sci­en­tists have pub­lished new glob­al maps of the Earth at night, pro­vid­ing the rich­est and clear­est views of most of the plan­et’s set­tle­ments. Satel­lite images of the Earth at night (often referred to as “night illu­mi­na­tion”) have been a fun­da­men­tal research tool for 25 years. Cre­at­ed once a decade, maps are ubiq­ui­tous in pop cul­ture, eco­nom­ics, soci­ol­o­gy, and envi­ron­men­tal research.

Night Earth from NASA

Con­tin­u­ing the theme of pho­tos of the Earth from space, I present to you a new selec­tion of amaz­ing shots. All pho­tographs were tak­en at the NASA Obser­va­to­ry by Joshua Stevens using Suo­mi NPP VIIRS data from NASA’s God­dard Space Flight Cen­ter. Since the launch of the satel­lite in 2011, sci­en­tists at the NPP team have been ana­lyz­ing night light data and devel­op­ing new soft­ware and algo­rithms to make night light images clear­er, more accu­rate and eas­i­ly acces­si­ble. Today, they are on the verge of pro­vid­ing a dai­ly, high-qual­i­ty night view of the Earth and are ready to pro­vide a sim­i­lar ser­vice to the sci­en­tif­ic com­mu­ni­ty this year.

Sci­en­tists have been cre­at­ing remote sens­ing tech­niques to fil­ter out stray light sources, receive a bet­ter and more con­sis­tent sig­nal, and process the image instant­ly. A spe­cial fil­ter called VIIRS has been devel­oped, the first satel­lite-based instru­ment capa­ble of mak­ing quan­ti­ta­tive mea­sure­ments of light emis­sion. It allows researchers to dis­tin­guish between the inten­si­ty, types, and sources of night­time light­ing across mul­ti­ple years of data. The Suo­mi satel­lite observes most of the Earth­’s loca­tions at approx­i­mate­ly 1:30 PM and 1:30 AM each day, trac­ing the plan­et in ver­ti­cal 3,000-kilometer bands from pole to pole. VIIRS instant­ly per­forms all the nec­es­sary trans­for­ma­tions, and the data appears in the pub­lic domain with­in a mat­ter of hours.

Armed with more accu­rate night­time instru­ments, NASA’s team is now automat­ing pro­cess­ing so that users can view Earth­’s nightscapes vir­tu­al­ly online. The tool has poten­tial in short-term weath­er fore­cast­ing and emer­gency response. “With VIIRS, we can observe short-term changes caused by pow­er out­ages due to con­flicts, storms, earth­quakes and black­outs,” said one devel­op­er. “We can see the cycli­cal changes dri­ven by human activ­i­ty, includ­ing hol­i­day light­ing and sea­son­al migra­tions. We can also observe grad­ual changes as a result of urban­iza­tion, emi­gra­tion, eco­nom­ic changes and elec­tri­fi­ca­tion.”

See also
Czech Switzerland by Martin Rak

In con­tin­u­a­tion of the top­ic, I advise you to admire the incred­i­ble pho­tographs of space from NASA in a sep­a­rate arti­cle.