As the Mars Curiosity Rover continues to find interesting-looking rocks on the surface of the Red Planet, Earth’s so-called “twin” planet Venus has meanwhile become the source of many astronomical mysteries. Last week, an atmospheric scientist published a report claiming that dark streaks seen in Venus’ atmosphere might be signs of rich microbial life. At a certain depth, the atmosphere on Venus drops to between 30ºC and 70ºC (86ºF to 158ºF) and has at atmospheric pressure similar to the pressure on Earth’s surface. Since microbes are known to exist high in Earth’s atmosphere, it’s plausible that life could exist in this part of the Venusian atmosphere. For that reason and others, NASA and Russia have begun discussing a joint mission to explore Venus sometime in the next decade.
That mission might become a more pressing priority for space agencies thanks to the discovery of further mysterious phenomenon on Venus. According to data published in Nature Geoscience, astronomers have discovered an unexplained “gravity wave” occurring in Venus’ atmosphere.
The wave was spotted by the Japanese spacecraft Akatsuki, also known as the Venus Climate Orbiter (VCO). Gravity waves differ from gravitational waves, which are waves occurring within the medium of gravity itself. Gravity waves, on the other hand, occur in fluid media such as liquids or air (or at the interface between the two) when the force of gravity counteracts buoyancy, creating the typical ripple-like effects seen in waves such as those found on Earth’s beaches or in certain cloud formations.
The wave spotted on Venus measured 10,000 km (600 miles) across Venus’ atmosphere and lasted several days. Prior to the discovery of this wave, it was thought that gravity waves of this size were not possible in our solar system. According to the article, the presence of such a wave cannot be explained by any current knowledge of conditions on Venus:
From conventional knowledge of the Venusian atmosphere, the
formation and propagation of such mountain waves appear difficult.
Until research can be conducted on the surface of Venus itself, the cause of such a wave remains a mystery. While certain topographical features are thought to have possibly contributed to this gravity wave, the sheer size of this anomaly suggests there are unknown forces at work. If NASA ever grows tired of zapping weird rocks on Mars, we might find that other neighbors in our solar system are much more mysterious.