Satellites are like guardians of our planet. From monitoring land, oceans, nature, and weather patterns to aiding communication and connectivity, satellites orbiting in space play a vital role in safeguarding Earth and improving our daily lives.
The images captured by satellites hold a wealth of information. Recently, while reviewing images of Earth taken by the weather satellites Himawari-8 and Himawari-9, a team of international scientists spotted a surprisingly ‘familiar face’ sneaking behind our planet.
Crowned the hottest planet in our Solar System, Venus has been quietly photobombing Earth’s satellite images for nearly a decade. This discovery is a eureka moment for astronomers, as it reveals a new way to track Venusian weather over the past ten years, the longest continuous observation of the planet to date.
Venus has a thick blanket of atmosphere but it’s far from cozy. Composed mostly of carbon dioxide and cloaked in thick clouds of sulfuric acid, it’s hot and harsh. Observing Venus from Earth’s surface or even from space is challenging due to interference from Earth’s own atmosphere, cloud cover, and sunlight. Earlier space-based observations were also limited in both duration and the range of light (wavelengths) they could detect. This is where weather satellites come to the rescue.
By studying ten years of images from Himawari-8 and Himawari-9, the team identified 437 appearances of Venus as a tiny dot in the pictures. Even that tiny dot revealed valuable data about how weather and temperature in the Venusian atmosphere changed over time. The team observed that significant temperature shifts occurred around Venusian sunrise. Scientists believe these changes are linked to planetary waves, large-scale movements of air caused by a planet’s rotation, similar to how water moves in a stirred glass. These waves circulate through the atmosphere and oceans, shaping weather patterns.
Now, scientists are actively exploring the potential of using weather satellites as an additional pair of ‘eyes’ to study other planetary atmospheres from space. Could this approach uncover more hidden secrets of our Solar System? Only future observations will tell.
Cool Fact
Did you know that Himawari means ‘sunflower’ in Japanese? These satellites can detect light across a broad spectrum, in 16 different colours. Their wide field of view, larger than Earth itself, even allows them to capture other cosmic objects within the frame.
(Space Scoop)