NOAA’s newest satellite, GOES-19, provided a beautiful view of Earth during the winter solstice. Currently positioned over the Western Hemisphere at 89.5° west longitude, between NOAA’s GOES East and GOES West satellites, GOES-19 captured this celestial moment from space while undergoing post-launch testing. Launched on June 25, it is set to replace GOES-16 in the GOES East position this spring.
The winter solstice marks a special moment as the shortest day and longest night of the year in the Northern Hemisphere. At precisely 4:21 a.m. EST, the Northern Hemisphere reached its maximum tilt away from the sun, positioning the sun directly over the Tropic of Capricorn, 23.5° south of the equator.
GOES-19’s position over the Western Hemisphere provides a clear view of the contrast between day and night on the shortest day of the year. On Dec. 21, 2024, NOAA’s GOES-19 captured this image of Earth during the winter solstice shortly after the Northern Hemisphere reached its maximum tilt away from the sun, positioning the sun directly over the Tropic of Capricorn at 23.5° south latitude.
GOES-19’s images reveal the terminator—the shadow line that divides day and night—cutting a sharp angle across Earth. During this event, the North Pole is shrouded in 24-hour darkness, while the South Pole experiences 24-hour daylight—a contrast that flips in June during the summer solstice.
This animation, captured by NOAA’s GOES-19, shows a timelapse of Earth’s rotation from Oct. 3 to Dec. 20, 2024. It highlights the gradual shift in Earth's tilt relative to the sun and the changing position of the terminator—the line dividing day and night—as the Northern Hemisphere tilts further away from the sun.
The solstice doesn’t result in the latest sunrise or the earliest sunset. These occur a couple of weeks before and after the solstice due to Earth’s 23.5° tilt and its slightly elliptical orbit around the sun.
The winter solstice also signals the start of astronomical winter, which is defined by Earth’s position relative to the sun. This differs from meteorological winter, which is based on temperature patterns and starts on Dec. 1.
The sun rises over the Potomac River between Washington, D.C., and Virginia on the morning of the winter solstice, Saturday, Dec. 21, marking the shortest day of the year.
What Makes GOES-19 Special?
GOES-19 is the fourth and final satellite in NOAA’s advanced GOES-R series. While still undergoing scheduled testing before becoming operational, its current position provides a view of Earth that complements its “siblings” GOES East and GOES West. GOES-19 is also equipped with NOAA’s first coronagraph, Compact Coronagraph-1 (CCOR-1), designed to observe the outer atmosphere of the sun, called the corona. This capability enables GOES-19 to monitor space weather events that could disrupt power grids, communication networks, navigation systems, and more.
GOES-19's position and view over the Western Hemisphere at its current checkout location and its future operational location.
In March 2025 GOES-19 will move to its operational location at 75.2° west longitude, where it will officially assume the title and role of GOES East in and replace GOES-16 in April. This transition ensures NOAA’s satellite constellation continues to provide critical data for weather forecasts, storm tracking, and environmental monitoring. GOES-16 will become the primary on-orbit back-up for the GOES constellation.
Imagery and data from GOES-19 during the post-launch testing phase should be considered preliminary and non-operational.