Globe at Night Data Show Night Sky Brightening at 9.6% Annually

AI digestMimile.ai EditorialAugust 10, 2026 at 05:30 AM

This digest was compiled by AI from multiple sources — links to the originals are below.

Globe at Night Data Show Night Sky Brightening at 9.6% Annually

A study using 51,351 naked-eye observations from the Globe at Night programme found that night sky brightness increased by 9.6% annually from 2011 to 2022, according to research published in Science in 2023. The rate is far higher than the 1.8% per year estimated by satellite measurements, as artificial light scattering, especially blue light, escapes orbital sensors.

The Brightening Trend

Researchers analyzed 51,351 naked-eye reports from Globe at Night, a citizen-science project of NSF’s NOIRLab, collected from 2011 to 2022 across 19,262 locations. The data showed sky brightness increasing by 9.6% annually on average, with Europe experiencing a 6.5% rise and North America 10.4%. If the trend persists, a child who sees 250 stars tonight would see fewer than 100 from the same place by age 18, a fourfold reduction over 18 years.

Why Satellites Underestimated

Satellite-based measurements, such as from the VIIRS Day/Night Band instrument, had previously indicated slower growth: about 2.2% per year in lit area and 1.8% in total radiance from 2012 to 2016. The VIIRS sensor is insensitive to blue light below 500 nanometres, missing much of the emission from white LEDs that now dominate outdoor lighting. It also fails to detect sideways light, which scatters through the atmosphere and contributes to skyglow far from the source, leading to a significant underestimation of ground-level brightening.

What's Next

The study’s authors suggest that future satellite instruments should cover the full visible spectrum to accurately monitor light pollution. Whether municipalities and nations will adopt lighting policies that mandate warmer-color LEDs and better shielding to protect dark skies remains uncertain.

1 source

Globe at Night Data Show Night Sky Brightening at 9.6% Annually

spacedaily.com

Space Daily

Science

Astronomers find third giant planet hidden in Beta Pictoris debris disk

Two research teams have announced the discovery of a third giant planet, Beta Pictoris d, orbiting the young star Beta Pictoris, 63 light-years from Earth. The planet, with a mass two to four times that of Jupiter, was found hiding in the glare of the star’s bright debris disk while astronomers were studying the system’s known planets with the James Webb Space Telescope.

Science

Webb telescope maps clouds on exoplanet 690 light-years away

Astronomers using the James Webb Space Telescope have mapped cloud patterns on exoplanet WASP-94 A b, located 690 light-years from Earth. The study, published in Nature on May 21, reveals streaming and vanishing clouds by analyzing how the planet filters starlight.

Science

Kyoto University scientists map thermospheric density using 1,200 Starlink satellites

Researchers at Kyoto University use orbital data from about 1,200 Starlink satellites to produce the first two-dimensional map of thermospheric density. The map, at roughly 500 kilometers altitude, shows density patterns consistent with observations from the European Space Agency's SWARM satellites. The work builds on an earlier Starlink-based study that tracked density changes over time and altitude.

Science

Kyoto University researchers map thermosphere using 1,200 Starlink satellites

Kyoto University researchers announced August 12 that they reconstructed thermospheric density about 500 km above Earth using orbital data from roughly 1,200 Starlink satellites. The team applied tomography to satellite orbit decay to produce the first two-dimensional latitude-longitude map of the thermosphere. The method could sharpen satellite tracking and reduce collision risk even as low Earth orbit grows more crowded.

Globe at Night Data Show Night Sky Brightening at 9.6% Annually

The Brightening Trend

Why Satellites Underestimated

What's Next

Read more

Read more