Astronomers have been studying various planets in our solar system for generations. While modern scientific instruments and telescopes have given us detailed information on planets, such as Venus, some aspects of planets in our social system have remained a mystery. One example is nighttime weather on Venus.
Little has been known about the weather at night on Venus because the absence of sunlight makes imaging weather patterns difficult. Recently, researchers developed a way to use the infrared sensors aboard Japan’s Venus orbiter Akatsuki to reveal details of nighttime whether on the planet. Analytical methods could also be used to study other planets in the solar system, including Mars, among others.
Scientists on the project note that studying Venusian weather using their new method could also allow scientists to learn more about the mechanisms driving weather systems here on Earth. Earth and Venus are drastically different but do have a lot in common. They are similar in size and mass, and both orbit the sun within the same orbital region known as the habitable zone. Both planets have a solid surface and a narrow atmosphere that experiences whether.
Venus and Earth are similar enough that studying whether on Venus can help scientists learn more about our planet. Previously, only the dayside of Venus was easily accessible by scientific instruments. By leveraging Akatsuki’s infrared imager, scientists didn’t need sunlight to make observations. However, they are clear that the infrared imagery aboard the orbiter cannot resolve details on the nightside of Venus but gives researchers data allowing them to observe things indirectly.
Team members were able to combine images to suppress noise that typically obscures small-scale cloud patterns. On Venus, the entire weather system rotates quickly, and scientists had to compensate for the movement, which is known as super-rotation, to highlight interesting formations for study. The team is exploring the mechanisms that sustain Venus’ super-rotation and think that weather characteristics at night might help explain it.
One interesting observation already made using the data is that the North-Southwinds at night rotate in the opposite direction compared to their daytime counterparts. More data on the unusual weather will be gathered in the future. NASA has two missions that will explore Venus in the coming years.