SpaceX and Amazon Satellites Are An Existential Threat to Astronomy
Light from thousands of satellites makes it difficult to study objects in space
A few hundred years ago, we would gaze upon a brilliant night sky illuminated with nothing but stars. In the past century, we gained the capability to send objects into orbit around the Earth. Now when faster-moving specks of light, satellites, are also visible in our night skies.
These incredible feats of physics and engineering do have a measurable downside. Many of these satellites also emit considerable amounts of light. Early astronomers already predicted that this could become a problem. At a certain point, the artificial light would make some objects impossible to see or study.
During the General Assembly of the International Astronomical Union in 1979 physicists set a guideline for building observatories. The guidance suggested avoiding any regions where the artificial illumination exceeds 10%. A troubling new study finds this limitation is exceeded everywhere on our planet.
Scientists published a letter in the Monthly Notices of the Royal Astronomical Society on March 29th, 2021, detailing these findings.
