Imaging data from Japan’s Himawari-8 and -9 meteorological satellites have been successfully used to monitor temporal changes in Venus’ cloud-top temperature, revealing unseen patterns in the temperature structure of various waves.
Imaging data from Japan’s Himawari-8 and -9 meteorological satellites have been successfully used to monitor temporal changes in Venus’ cloud-top temperature, revealing unseen patterns in the temperature structure of various waves. A team led by the University of Tokyo collated infrared images from 2015–25 to estimate brightness temperatures on day to year scales. The results demonstrate that meteorological satellites can serve as additional eyes to access the Venusian atmosphere from space and complement future observations from planetary missions and ground-based telescopes.
The Himawari-8 and -9 satellites, launched in 2014 and 2016, respectively, were developed to monitor global atmospheric phenomena through use of their multispectral Advanced Himawari Imagers (AHIs). The University of Tokyo team led by visiting researcher Gaku Nishiyama saw the opportunity to use the cutting-edge sensor data for spaceborne observations of Venus, which is coincidentally captured by the AHIs near the Earth’s rim.
Observing temporal temperature variations in the cloud tops of Venus is essential to understand its atmospheric dynamics and related phenomena, such as thermal tides and planetary-scale waves. Obtaining data for these phenomena presents multiple challenges, as Nishiyama explained. “The atmosphere of Venus has been known to exhibit year-scale variations in reflectance and wind speed; however, no planetary mission has succeeded in continuous observation for longer than 10 years due to their mission lifetimes,” he said. “Ground-based observations can also contribute to long-term monitoring, but their observations generally have limitations due to the Earth’s atmosphere and sunlight during the daytime.”
Read more at University of Tokyo
Image: A photo with magnified sections to show just how small Venus is in the field of view of the observation satellites. Despite this limitation, researchers can still gather useful data. (Credit: ©2025 Nishiyama et al. CC-BY-ND)
