ESA | Science & Technology | Venus Express | 2017 Sep 14
Scientists have used ESA’s Venus Express to characterise the wind and upper cloud patterns on the night side of Venus for the first time-with surprising results.
[img3="Atmospheric super-rotation at the upper clouds of Venus.The study shows that atmosphere on Venus’ night side behaves very differently to that on the side of the planet facing the Sun (the ‘dayside’), exhibiting unexpected and previously-unseen cloud types, morphologies, and dynamics -- some of which appear to be connected to features on the planet’s surface. ...
Credit: ESA, JAXA, J. Peralta and R. Hueso"]http://sci.esa.int/science-e-media/img/ ... on_625.jpg[/img3][hr][/hr]
Venus’ atmosphere is dominated by strong winds that whirl around the planet far faster than Venus itself rotates. This phenomenon, known as ‘super-rotation,’ sees Venusian winds rotating up to 60 times faster than the planet below, pushing and dragging along clouds within the atmosphere as they go. These clouds travel fastest at the upper cloud level, some 65 to 72 km above the surface. ...
The team used the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) on ESA’s Venus Express spacecraft to observe the clouds in the infrared. “VIRTIS enabled us to see these clouds properly for the first time, allowing us to explore what previous teams could not -- and we discovered unexpected and surprising results,” adds Peralta.
Rather than capturing single images, VIRTIS gathered a ‘cube’ of hundreds of images of Venus acquired simultaneously at different wavelengths. This allowed the team to combine numerous images to improve the visibility of the clouds, and see them at unprecedented quality. The VIRTIS images thus reveal phenomena on Venus’ night side that have never before been seen on the dayside. ...
Stationary Waves and Slowly Moving Features in the Night Upper Clouds of Venus - J. Peralta et al
- Nature Astronomy 1:0187 (online 24 Jul 2017) DOI: 10.1038/s41550-017-0187
arXiv.org > astro-ph > arXiv:1707.07796 > 25 Jul 2017 (v1), 26 Jul 2017 (v2)
- Nature Geoscience 10(2):85 (Feb 2017) DOI: 10.1038/ngeo2873